Drosophila melanogaster#Vision

The term "Drosophila", meaning "dew-loving", is a modern scientific Latin adaptation from Greek words {{lang|el|δρόσος}}, {{lang|el|drósos}}, "dew", and {{lang|el|φιλία}}, {{lang|el|philía}}, "lover". The term "melanogaster" meaning "black-belly", comes from Ancient Greek {{lang|el|μέλας}}, {{lang|el|mélas}}, "black", and {{lang|el|γᾰστήρ}}, {{lang|el|gastḗr}}, "belly".{{cn|date=March 2025}}

Unlike humans, the sex and physical appearance of fruit flies is not influenced by hormones.{{cite journal | last=Kelley | first=Darcy B. | last2=Bayer | first2=Emily A. | title=Sexual dimorphism: Neural circuit switches in the Drosophila brain | journal=Current Biology | publisher=Elsevier BV | volume=31 | issue=6 | year=2021 | issn=0960-9822 | doi=10.1016/j.cub.2021.02.026 | pages=R297–R298}} The appearance and sex of fruit flies is determined only by genetic information.

Female fruit flies are substantially larger than male fruit flies, with females having bodies that are up to 30% larger than an adult male.{{cite journal | last=Paloma Álvarez-Rendón | first=Jéssica | last2=Manuel Murillo-Maldonado | first2=Juan | last3=Rafael Riesgo-Escovar | first3=Juan | title=The insulin signaling pathway a century after its discovery: Sexual dimorphism in insulin signaling | journal=General and Comparative Endocrinology | publisher=Elsevier BV | volume=330 | year=2023 | issn=0016-6480 | doi=10.1016/j.ygcen.2022.114146 | page=114146}} "... adult females are 30 % bigger than males; these differences happen during larval life."{{cite journal | last=Cowley | first=D E | last2=Atchley | first2=W R | title=Quantitative Genetics of Drosophila Melanogaster. II. Heritabilities and Genetic Correlations between Sexes for Head and Thorax Traits. | journal=Genetics | publisher=Oxford University Press (OUP) | volume=119 | issue=2 | date=1988-06-01 | issn=1943-2631 | doi=10.1093/genetics/119.2.421 | pages=421–433| pmc=1203424 }}

Wild type fruit flies are yellow-brown, with brick-red eyes and transverse black rings across the abdomen. The black portions of the abdomen are the inspiration for the species name (melanogaster = "black-bellied"). The brick-red color of the eyes of the wild type fly are due to two pigments:{{cite book | vauthors = Ewart GD, Howells AJ | chapter = ABC transporters involved in transport of eye pigment precursors in Drosophila melanogaster | series = Methods in Enzymology | volume = 292 | pages = 213–24 | date = 1998-01-01 | pmid = 9711556 | doi = 10.1016/S0076-6879(98)92017-1 | publisher = Academic Press | isbn = 978-0-12-182193-7 | title = ABC Transporters: Biochemical, Cellular, and Molecular Aspects }} xanthommatin, which is brown and is derived from tryptophan, and drosopterins, which are red and are derived from guanosine triphosphate. They exhibit sexual dimorphism; females are about {{convert|2.5|mm|abbr=on|2}} long; males are slightly smaller. Furthermore, males have a cluster of spiky hairs (claspers) surrounding the reproducing parts used to attach to the female during mating. Extensive images are found at FlyBase.{{cite web | title = FlyBase: A database of Drosophila genes and genomes | publisher = Genetics Society of America | year = 2009 | access-date = August 11, 2009 | url = http://flybase.bio.indiana.edu/ | archive-url = https://web.archive.org/web/20090815020557/http://flybase.bio.indiana.edu/ | archive-date = August 15, 2009 }}

File:Biology Illustration Animals Insects Drosophila melanogaster.svg

Drosophila melanogaster can be distinguished from related species by the following combination of features: gena ~1/10 diameter of eye at greatest vertical height; wing hyaline and with costal index 2.4; male protarsus with a single row of ~12 setae forming a sex comb; male epandrial posterior lobe small and nearly triangular; female abdominal tergite 6 with dark band running to its ventral margin; female oviscapt small, pale, without dorsodistal depression and with 12-13 peg-like outer ovisensilla.{{Cite journal |last1=Yuzuki |first1=Keven |last2=Tidon |first2=Rosana |date=2020 |title=Identification key for drosophilid species (Diptera, Drosophilidae) exotic to the Neotropical Region and occurring in Brazil |journal=Revista Brasileira de Entomologia |volume=64 |issue=1 |doi=10.1590/1806-9665-rbent-2019-100 |s2cid=211570766 |issn=1806-9665|doi-access=free }}{{Cite journal |last1=Miller |first1=M. E. |last2=Marshall |first2=S. A. |last3=Grimaldi |first3=D. A. |date=2017 |title=A Review of the Species of Drosophila (Diptera: Drosophilidae) and Genera of Drosophilidae of Northeastern North America |url=https://cjai.biologicalsurvey.ca/articles/mmg-31/ |journal=Canadian Journal of Arthropod Identification |volume=31 |doi=10.3752/cjai.2017.31|doi-access=free }}

Drosophila melanogaster flies can sense air currents with the hairs on their backs. Their eyes are sensitive to slight differences in light intensity and will instinctively fly away when a shadow or other movement is detected.{{cite web | title = Drosophila Melanogaster | publisher = Animal Diversity Web | year = 2000 | access-date = August 11, 2009 | url = https://animaldiversity.org/accounts/Drosophila_melanogaster/ | archive-date = November 30, 2014 | archive-url = https://web.archive.org/web/20141130044743/http://animaldiversity.org/accounts/Drosophila_melanogaster/ }}

File:Drosophila egg.png

Under optimal growth conditions at {{convert|25|C|F}}, the D. melanogaster lifespan is about 50 days from egg to death.{{cite journal | vauthors = Linford NJ, Bilgir C, Ro J, Pletcher SD | title = Measurement of lifespan in Drosophila melanogaster | journal = Journal of Visualized Experiments | issue = 71 | date = January 2013 | pmid = 23328955 | pmc = 3582515 | doi = 10.3791/50068 }} The developmental period for D. melanogaster varies with temperature, as with many ectothermic species. The shortest development time (egg to adult), seven days, is achieved at {{convert|28|C|F}}.{{cite book | vauthors = Ashburner M, Thompson JN | author-link1 = Michael Ashburner | chapter = The laboratory culture of Drosophila |title=The genetics and biology of Drosophila |editor=Ashburner M, Wright TRF | volume= 2A |pages=1–81 | publisher = Academic Press | year = 1978 | no-pp = true }}{{cite book | vauthors = Ashburner M, Golic KG, Hawley RS | author-link1 = Michael Ashburner | title = Drosophila: A Laboratory Handbook. | pages = 162–4 | edition = 2nd | publisher = Cold Spring Harbor Laboratory Press | year = 2005 | isbn = 978-0-87969-706-8 }} Development times increase at higher temperatures (11 days at {{convert|30|C|F|disp=or}}) due to heat stress. Under ideal conditions, the development time at {{convert|25|C|F}} is {{frac|8|1|2}} days,[http://flystocks.bio.indiana.edu/ Bloomington Drosophila Stock Center] at Indiana University: [http://flystocks.bio.indiana.edu/Fly_Work/culturing.htm#stockkeeping Basic Methods of Culturing Drosophila] {{Webarchive|url=https://web.archive.org/web/20060901073454/http://flystocks.bio.indiana.edu/Fly_Work/culturing.htm#stockkeeping |date=2006-09-01 }} at {{convert|18|C|F}} it takes 19 days and at {{convert|12|C|F}} it takes over 50 days. Under crowded conditions, development time increases,{{cite journal | vauthors = Chiang HC, Hodson AC | title = An analytical study of population growth in Drosophila melanogaster | journal = Ecological Monographs | year = 1950 | volume = 20 | pages = 173–206 | jstor = 1948580| doi = 10.2307/1948580 | issue = 3 | bibcode = 1950EcoM...20..173C }} while the emerging flies are smaller.{{cite journal | vauthors = Bakker K| title = An analysis of factors which determine success in competition for food among larvae of Drosophila melanogaster | journal = Archives Néerlandaises de Zoologie | year = 1961 | volume = 14 | pages = 200–281 | doi = 10.1163/036551661X00061 | issue = 2 | s2cid = 85129022 }} Females lay some 400 eggs (embryos), about five at a time, into rotting fruit or other suitable material such as decaying mushrooms and sap fluxes. Drosophila melanogaster is a holometabolous insect, so it undergoes a full metamorphosis. Their life cycle is broken down into four stages: embryo, larva, pupa, adult.{{cite book | vauthors = Fernández-Moreno MA, Farr CL, Kaguni LS, Garesse R | chapter = Drosophila melanogaster as a Model System to Study Mitochondrial Biology | title = Mitochondria | volume = 372 | pages = 33–49 | date = 2007 | pmid = 18314716 | pmc = 4876951 | doi = 10.1007/978-1-59745-365-3_3 | isbn = 978-1-58829-667-2 | series = Methods in Molecular Biology }} The eggs, which are about 0.5 mm long, hatch after 12–15 hours (at {{convert|25|C|F|disp=or}}). The resulting larvae grow for about four days (at 25 °C) while molting twice (into second- and third-instar larvae), at about 24 and 48 hours after hatching. During this time, they feed on the microorganisms that decompose the fruit, as well as on the sugar of the fruit itself. The mother puts feces on the egg sacs to establish the same microbial composition in the larvae's guts that has worked positively for herself.{{cite journal | vauthors = Blum JE, Fischer CN, Miles J, Handelsman J | title = Frequent replenishment sustains the beneficial microbiome of Drosophila melanogaster | journal = mBio | volume = 4 | issue = 6 | pages = e00860-13 | date = November 2013 | pmid = 24194543 | pmc = 3892787 | doi = 10.1128/mBio.00860-13 }} Then the larvae encapsulate in the puparium and undergo a four-day-long metamorphosis (at 25 °C), after which the adults eclose (emerge).

File:Arrhythmia-Caused-by-a-Drosophila-Tropomyosin-Mutation-Is-Revealed-Using-a-Novel-Optical-Coherence-pone.0014348.s001.ogg

Males perform a sequence of five behavioral patterns to court females. First, males orient themselves while playing a courtship song by horizontally extending and vibrating their wings. Soon after, the male positions himself at the rear of the female's abdomen in a low posture to tap and lick the female genitalia. Finally, the male curls his abdomen and attempts copulation. Females can reject males by moving away, kicking, and extruding their ovipositor.{{cite journal| vauthors = Cook R, Connolly K |s2cid=85393769| name-list-style = vanc |title=Rejection Responses by Female Drosophila melanogaster: Their Ontogeny, Causality and Effects upon the Behaviour of the Courting Male|journal=Behaviour|date=1973|volume=44|issue=1/2|pages=142–166|jstor=4533484|doi=10.1163/156853973x00364}} Copulation lasts around 15–20 minutes,{{cite journal | vauthors = Houot B, Svetec N, Godoy-Herrera R, Ferveur JF | title = Effect of laboratory acclimation on the variation of reproduction-related characters in Drosophila melanogaster | journal = The Journal of Experimental Biology | volume = 213 | issue = Pt 13 | pages = 2322–31 | date = July 2010 | pmid = 20543131 | doi = 10.1242/jeb.041566 | doi-access = free }} during which males transfer a few hundred, very long (1.76 mm) sperm cells in seminal fluid to the female.{{cite book | title = Developmental Biology | vauthors = Gilbert SF | year = 2006 | chapter = 9: Fertilization in Drosophila | publisher = Sinauer Associates | chapter-url = http://8e.devbio.com/article.php?ch=9&id=87 | isbn = 978-0-87893-250-4 |edition= 8th | archive-url = https://web.archive.org/web/20070207233537/http://8e.devbio.com/article.php?ch=9&id=87 | archive-date = 2007-02-07 }} Females store the sperm in a tubular receptacle and in two mushroom-shaped spermathecae; sperm from multiple matings compete for fertilization. A last male precedence is believed to exist; the last male to mate with a female sires about 80% of her offspring. This precedence was found to occur through both displacement and incapacitation.{{cite journal | vauthors = Price CS, Dyer KA, Coyne JA | title = Sperm competition between Drosophila males involves both displacement and incapacitation | journal = Nature | volume = 400 | issue = 6743 | pages = 449–52 | date = July 1999 | pmid = 10440373 | doi = 10.1038/22755 | s2cid = 4393369 | bibcode = 1999Natur.400..449P }} The displacement is attributed to sperm handling by the female fly as multiple matings are conducted and is most significant during the first 1–2 days after copulation. Displacement from the seminal receptacle is more significant than displacement from the spermathecae. Incapacitation of first male sperm by second male sperm becomes significant 2–7 days after copulation. The seminal fluid of the second male is believed to be responsible for this incapacitation mechanism (without removal of first male sperm) which takes effect before fertilization occurs. The delay in effectiveness of the incapacitation mechanism is believed to be a protective mechanism that prevents a male fly from incapacitating his own sperm should he mate with the same female fly repetitively. Sensory neurons in the uterus of female D. melanogaster respond to a male protein, sex peptide, which is found in semen. This protein makes the female reluctant to copulate for about 10 days after insemination. The signal pathway leading to this change in behavior has been determined. The signal is sent to a brain region that is a homolog of the hypothalamus and the hypothalamus then controls sexual behavior and desire. Gonadotropic hormones in Drosophila maintain homeostasis and govern reproductive output via a cyclic interrelationship, not unlike the mammalian estrous cycle.{{cite journal | vauthors = Meiselman M, Lee SS, Tran RT, Dai H, Ding Y, Rivera-Perez C, Wijesekera TP, Dauwalder B, Noriega FG, Adams ME | display-authors = 6 | title = Drosophila melanogaster | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 114 | issue = 19 | pages = E3849–E3858 | date = May 2017 | pmid = 28439025 | pmc = 5441734 | doi = 10.1073/pnas.1620760114 | doi-access = free }} Sex peptide perturbs this homeostasis and dramatically shifts the endocrine state of the female by inciting juvenile hormone synthesis in the corpus allatum.{{cite journal | vauthors = Moshitzky P, Fleischmann I, Chaimov N, Saudan P, Klauser S, Kubli E, Applebaum SW | title = Sex-peptide activates juvenile hormone biosynthesis in the Drosophila melanogaster corpus allatum | journal = Archives of Insect Biochemistry and Physiology | volume = 32 | issue = 3–4 | pages = 363–74 | date = 1996 | pmid = 8756302 | doi = 10.1002/(SICI)1520-6327(1996)32:3/4<363::AID-ARCH9>3.0.CO;2-T }}

D. melanogaster is often used for life extension studies, such as to identify genes purported to increase lifespan when mutated.{{cite journal | vauthors = Carnes MU, Campbell T, Huang W, Butler DG, Carbone MA, Duncan LH, Harbajan SV, King EM, Peterson KR, Weitzel A, Zhou S, Mackay TF | display-authors = 6 | title = The Genomic Basis of Postponed Senescence in Drosophila melanogaster | journal = PLOS ONE | volume = 10 | issue = 9 | pages = e0138569 | year = 2015 | pmid = 26378456 | pmc = 4574564 | doi = 10.1371/journal.pone.0138569 | bibcode = 2015PLoSO..1038569C | doi-access = free }} D. melanogaster is also used in studies of aging. Werner syndrome is a condition in humans characterized by accelerated aging. It is caused by mutations in the gene WRN that encodes a protein with essential roles in repair of DNA damage. Mutations in the D. melanogaster homolog of WRN also cause increased physiologic signs of aging, such as shorter lifespan, higher tumor incidence, muscle degeneration, reduced climbing ability, altered behavior and reduced locomotor activity.{{cite journal | vauthors = Cassidy D, Epiney DG, Salameh C, Zhou LT, Salomon RN, Schirmer AE, McVey M, Bolterstein E | display-authors = 6 | title = Evidence for premature aging in a Drosophila model of Werner syndrome | journal = Experimental Gerontology | volume = 127 | page = 110733 | date = November 2019 | pmid = 31518666 | pmc = 6935377 | doi = 10.1016/j.exger.2019.110733 }}

Meiotic recombination in D. melanogaster appears to be employed in repairing damage in germ-line DNA as indicated by the findings that meiotic recombination is induced by the DNA damaging agents ultraviolet light Prudhommeau C, Proust J. UV irradiation of poplar cells of Drosophila melanogaster embryos. V. A study of the meiotic recombination in females with chromosomes of different structure. Mutat Res. 1974 Apr;23(1):63-6. PMID 4209047 and mitomycin C.Schewe MJ, Suzuki DT, Erasmus U. The genetic effects of mitomycin C in Drosophila melanogaster. II. Induced meiotic recombination. Mutat Res. 1971 Jul;12(3):269-79. doi: 10.1016/0027-5107(71)90015-7. PMID 5563942

File:Fruit flies mating.jpg

Females become receptive to courting males about 8–12 hours after emergence.{{cite journal | vauthors = Pitnick S | title = Investment in testes and the cost of making long sperm in Drosophila | journal = American Naturalist | year = 1996 | volume = 148 | pages = 57–80 | doi = 10.1086/285911 | s2cid = 83654824 }} Specific neuron groups in females have been found to affect copulation behavior and mate choice. One such group in the abdominal nerve cord allows the female fly to pause her body movements to copulate.{{cite web|title=Fruit fly research may reveal what happens in female brains during courtship, mating|url=https://www.sciencedaily.com/releases/2014/07/140702122424.htm|access-date=October 5, 2014}} Activation of these neurons induces the female to cease movement and orient herself towards the male to allow for mounting. If the group is inactivated, the female remains in motion and does not copulate. Various chemical signals such as male pheromones often are able to activate the group.

Also, females exhibit mate choice copying. When virgin females are shown other females copulating with a certain type of male, they tend to copulate more with this type of male afterwards than naïve females (which have not observed the copulation of others). This behavior is sensitive to environmental conditions, and females copulate less in bad weather conditions.{{cite journal | vauthors = Dagaeff AC, Pocheville A, Nöbel S, Loyau A, Isabel G, Danchin E | date= 2016 |title=Drosophila mate copying correlates with atmospheric pressure in a speed learning situation. |journal=Animal Behaviour|volume=121|pages=163–174 | doi = 10.1016/j.anbehav.2016.08.022|doi-access=free }}

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File:Turning-Males-On-Activation-of-Male-Courtship-Behavior-in-Drosophila-melanogaster-pone.0021144.s006.ogv

D. melanogaster males exhibit a strong reproductive learning curve. That is, with sexual experience, these flies tend to modify their future mating behavior in multiple ways. These changes include increased selectivity for courting only intraspecifically, as well as decreased courtship times.

Sexually naïve D. melanogaster males are known to spend significant time courting interspecifically, such as with D. simulans flies. Naïve D. melanogaster will also attempt to court females that are not yet sexually mature, and other males. D. melanogaster males show little to no preference for D. melanogaster females over females of other species or even other male flies. However, after D. simulans or other flies incapable of copulation have rejected the males' advances, D. melanogaster males are much less likely to spend time courting nonspecifically in the future. This apparent learned behavior modification seems to be evolutionarily significant, as it allows the males to avoid investing energy into futile sexual encounters.{{cite journal| vauthors = Dukas R |title=Male fruit flies learn to avoid interspecific courtship|journal=Behavioral Ecology|date=2004|volume=15|issue=4|pages=695–698|doi=10.1093/beheco/arh068 |doi-access=free}}

In addition, males with previous sexual experience modify their courtship dance when attempting to mate with new females—the experienced males spend less time courting, so have lower mating latencies, meaning that they are able to reproduce more quickly. This decreased mating latency leads to a greater mating efficiency for experienced males over naïve males.{{cite journal | vauthors = Saleem S, Ruggles PH, Abbott WK, Carney GE | title = Sexual experience enhances Drosophila melanogaster male mating behavior and success | journal = PLOS ONE | volume = 9 | issue = 5 | pages = e96639 | date = 2014 | pmid = 24805129 | pmc = 4013029 | doi = 10.1371/journal.pone.0096639 | bibcode = 2014PLoSO...996639S | doi-access = free }} This modification also appears to have obvious evolutionary advantages, as increased mating efficiency is extremely important in the eyes of natural selection.

Both male and female D. melanogaster flies act polygamously (having multiple sexual partners at the same time).{{cite journal| vauthors = von Haartman L |title=Successive Polygamy|journal=Behaviour|date=1951|volume=3|issue=1|pages=256–273|doi=10.1163/156853951x00296}} In both males and females, polygamy results in a decrease in evening activity compared to virgin flies, more so in males than females. Evening activity consists of those in which the flies participate other than mating and finding partners, such as finding food.{{cite journal | vauthors = Vartak VR, Varma V, Sharma VK | title = Effects of polygamy on the activity/rest rhythm of male fruit flies Drosophila melanogaster | journal = Die Naturwissenschaften | volume = 102 | issue = 1–2 | page = 1252 | date = February 2015 | pmid = 25604736 | doi = 10.1007/s00114-014-1252-5 | bibcode = 2015SciNa.102....3V | s2cid = 7529509 }} The reproductive success of males and females varies, because a female only needs to mate once to reach maximum fertility. Mating with multiple partners provides no advantage over mating with one partner, so females exhibit no difference in evening activity between polygamous and monogamous individuals. For males, however, mating with multiple partners increases their reproductive success by increasing the genetic diversity of their offspring. This benefit of genetic diversity is an evolutionary advantage because it increases the chance that some of the offspring will have traits that increase their fitness in their environment.

The difference in evening activity between polygamous and monogamous male flies can be explained with courtship. For polygamous flies, their reproductive success increases by having offspring with multiple partners, and therefore they spend more time and energy on courting multiple females. On the other hand, monogamous flies only court one female, and expend less energy doing so. While it requires more energy for male flies to court multiple females, the overall reproductive benefits it produces has kept polygamy as the preferred sexual choice.

The mechanism that affects courtship behavior in Drosophila is controlled by the oscillator neurons DN1s and LNDs.{{cite journal | vauthors = Bateman AJ | title = Intra-sexual selection in Drosophila | journal = Heredity | volume = 2 | issue = Pt. 3 | pages = 349–68 | date = December 1948 | pmid = 18103134 | doi = 10.1038/hdy.1948.21 | doi-access = free }} Oscillation of the DN1 neurons was found to be effected by sociosexual interactions, and is connected to mating-related decrease of evening activity.

D. melanogaster remains one of the most studied organisms in biological research, particularly in genetics and developmental biology. It is also employed in studies of environmental mutagenesis.{{cn|date=March 2025}}

File:Drosophila Gene Linkage Map.svg's Drosophila melanogaster genetic linkage map: This was the first successful gene mapping work and provides important evidence for the chromosome theory of inheritance. The map shows the relative positions of allelic characteristics on the second Drosophila chromosome. The distance between the genes (map units) are equal to the percentage of crossing-over events that occurs between different alleles.]]

D. melanogaster was among the first organisms used for genetic analysis, and today it is one of the most widely used and genetically best-known of all eukaryotic organisms. All organisms use common genetic systems; therefore, comprehending processes such as transcription and replication in fruit flies helps in understanding these processes in other eukaryotes, including humans.{{cite book | vauthors = Pierce BA |title=Genetics: A Conceptual Approach |edition=2nd |publisher=W. H. Freeman |year=2004 |isbn=978-0-7167-8881-2 |url-access=registration |url=https://archive.org/details/geneticsconceptu0000unse }}

Thomas Hunt Morgan began using fruit flies in experimental studies of heredity at Columbia University in 1910 in a laboratory known as the Fly Room. The Fly Room was cramped with eight desks, each occupied by students and their experiments. They started off experiments using milk bottles to rear the fruit flies and handheld lenses for observing their traits. The lenses were later replaced by microscopes, which enhanced their observations. Morgan and his students eventually elucidated many basic principles of heredity, including sex-linked inheritance, epistasis, multiple alleles, and gene mapping.

D. melanogaster had historically been used in laboratories to study genetics and patterns of inheritance. However, D. melanogaster also has importance in environmental mutagenesis research, allowing researchers to study the effects of specific environmental mutagens.{{cite journal | vauthors = Kilbey BJ, MacDonald DJ, Auerbach C, Sobels FH, Vogel EW | title = The use of Drosophila melanogaster in tests for environmental mutagens | journal = Mutation Research | volume = 85 | issue = 3 | pages = 141–6 | date = June 1981 | pmid = 6790982 | doi = 10.1016/0165-1161(81)90029-7 }}

File:Fruit Fly Eye Colors.jpg

There are many reasons the fruit fly is a popular choice as a model organism:{{cn|date=March 2025}}

• Its care and culture require little equipment, space, and expense even when using large cultures.
• It can be safely and readily anesthetized (usually with ether, carbon dioxide gas, by cooling, or with products such as FlyNap).
• Its morphology is easy to identify once anesthetized.
• It has a short generation time (about 10 days at room temperature), so several generations can be studied within a few weeks.
• It has a high fecundity (females lay up to 100 eggs per day, and perhaps 2000 in a lifetime).
• Males and females are readily distinguished, and virgin females can be easily identified by their light-colored, translucent abdomen, facilitating genetic crossing.
• The mature larva has giant chromosomes in the salivary glands called polytene chromosomes, "puffs", which indicate regions of transcription, hence gene activity. The under-replication of rDNA occurs resulting in only 20% of DNA compared to the brain. Compare to the 47%, less rDNA in Sarcophaga barbata ovaries.
• It has only four pairs of chromosomes – three autosomes, and one pair of sex chromosomes.
• Males do not show meiotic recombination, facilitating genetic studies.
• Recessive lethal "balancer chromosomes" carrying visible genetic markers can be used to keep stocks of lethal alleles in a heterozygous state without recombination due to multiple inversions in the balancer.
• The development of this organism—from fertilized egg to mature adult—is well understood.
• Genetic transformation techniques have been available since 1987. One approach of inserting foreign genes into the Drosophila genome involves P elements. The transposable P elements, also known as transposons, are segments of bacterial DNA that are transferred into the fly genome. Transgenic flies have already contributed to many scientific advances, e.g., modeling such human diseases as Parkinson's, neoplasia, obesity, and diabetes.
• Its complete genome was sequenced and first published in 2000.{{cite journal |author1 = Adams MD|author2 = Celniker SE|author-link2=Susan Celniker|author3 = Holt RA|author4 = Evans CA|author5 = Gocayne JD|author6 = Amanatides PG|display-authors = etal | title = The genome sequence of Drosophila melanogaster | journal = Science | volume = 287 | issue = 5461 | pages = 2185–95 | date = March 2000 | pmid = 10731132 | doi = 10.1126/science.287.5461.2185 | citeseerx = 10.1.1.549.8639 | bibcode = 2000Sci...287.2185. }}
• Sexual mosaics can be readily produced, providing an additional tool for studying the development and behavior of these flies.{{cite journal | vauthors = Hotta Y, Benzer S | title = Mapping of behaviour in Drosophila mosaics | journal = Nature | volume = 240 | issue = 5383 | pages = 527–35 | date = December 1972 | pmid = 4568399 | doi = 10.1038/240527a0 | bibcode = 1972Natur.240..527H | s2cid = 4181921 }}

{{See also|Abdominal pigmentation in Drosophila melanogaster}}

File:Drosophila melanogaster Cy allele curly wings.svg

Genetic markers are commonly used in Drosophila research, for example within balancer chromosomes or P-element inserts, and most phenotypes are easily identifiable either with the naked eye or under a microscope. In the list of a few common markers below, the allele symbol is followed by the name of the gene affected and a description of its phenotype. (Note: Recessive alleles are in lower case, while dominant alleles are capitalised.)

• Cy¹: Curly; the wings curve away from the body, flight may be somewhat impaired
• e¹: Ebony; black body and wings (heterozygotes are also visibly darker than wild type)
• Sb¹: Stubble; bristles are shorter and thicker than wild type
• w¹: White; eyes lack pigmentation and appear white
• bw: Brown; eye color determined by various pigments combined.
• y¹: Yellow; body pigmentation and wings appear yellow, the fly analog of albinism

Drosophila genes are traditionally named after the phenotype they cause when mutated. For example, the absence of a particular gene in Drosophila will result in a mutant embryo that does not develop a heart. Scientists have thus called this gene tinman, named after the Oz character of the same name.{{cite journal | vauthors = Azpiazu N, Frasch M | title = tinman and bagpipe: two homeo box genes that determine cell fates in the dorsal mesoderm of Drosophila | journal = Genes & Development | volume = 7 | issue = 7B | pages = 1325–40 | date = July 1993 | pmid = 8101173 | doi = 10.1101/gad.7.7b.1325 | doi-access = free }} Likewise changes in the Shavenbaby gene cause the loss of dorsal cuticular hairs in Drosophila sechellia larvae.{{cite journal | vauthors = Stern DL, Frankel N | title = The structure and evolution of cis-regulatory regions: the shavenbaby story | journal = Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences | volume = 368 | issue = 1632 | page = 20130028 | date = December 2013 | pmid = 24218640 | pmc = 3826501 | doi = 10.1098/rstb.2013.0028 }} This system of nomenclature results in a wider range of gene names than in other organisms.

• b: black- The black mutation was discovered in 1910 by Thomas Hunt Morgan.{{cite journal | vauthors = Phillips AM, Smart R, Strauss R, Brembs B, Kelly LE | title = The Drosophila black enigma: the molecular and behavioural characterization of the black1 mutant allele | journal = Gene | volume = 351 | pages = 131–42 | date = May 2005 | pmid = 15878647 | doi = 10.1016/j.gene.2005.03.013 | url = https://epub.uni-regensburg.de/28573/1/brembs.pdf }} The black mutation results in a darker colored body, wings, veins, and segments of the fruit fly's leg.{{Cite web|url=http://flybase.org/reports/FBgn0000153#redbook_container|title=FlyBase Gene Report: Dmel\b|website=flybase.org|access-date=2019-03-26}} This occurs due to the fly's inability to create beta-alanine, a beta amino acid. The phenotypic expression of this mutation varies based on the genotype of the individual; for example, whether the specimen is homozygotic or heterozygotic results in a darker or less dark appearance. This genetic mutation is x-linked recessive.{{cite journal | vauthors = Sherald AF | title = Intergenic suppression of the black mutation of Drosophila melanogaster | journal = Molecular & General Genetics | volume = 183 | issue = 1 | pages = 102–6 | date = September 1981 | pmid = 6799739 | doi = 10.1007/bf00270146 | s2cid = 1210971 }}
• bw: brown- The brown eye mutation results from inability to produce or synthesize pteridine (red) pigments, due to a point mutation on chromosome II.{{cite journal | vauthors = Shoup JR | title = The development of pigment granules in the eyes of wild type and mutant Drosophila melanogaster | journal = The Journal of Cell Biology | volume = 29 | issue = 2 | pages = 223–49 | date = May 1966 | pmid = 5961338 | pmc = 2106902 | doi = 10.1083/jcb.29.2.223 }}
• m: miniature- One of the first records of the miniature mutation of wings was also made by Thomas Hunt Morgan in 1911. He described the wings as having a similar shape as the wild-type phenotype. However, their miniature designation refers to the lengths of their wings, which do not stretch beyond their body and, thus, are notably shorter than the wild-type length. He also noted its inheritance is connected to the sex of the fly and could be paired with the inheritance of other sex-determined traits such as white eyes.{{cite journal | vauthors = Morgan TH | title = The Origin of Nine Wing Mutations in Drosophila | journal = Science | volume = 33 | issue = 848 | pages = 496–9 | date = March 1911 | pmid = 17774436 | doi = 10.1126/science.33.848.496 | bibcode = 1911Sci....33..496M | jstor = 1638587 }} The wings may also demonstrate other characteristics deviant from the wild-type wing, such as a duller and cloudier color.{{Cite web|url=http://flybase.org/reports/FBgn0002577.html|title=FlyBase Gene Report: Dmel\m|website=flybase.org|access-date=2019-03-26}} Miniature wings are 1.5x shorter than wild-type but are believed to have the same number of cells. This is due to the lack of complete flattening by these cells, making the overall structure of the wing seem shorter in comparison. The pathway of wing expansion is regulated by a signal-receptor pathway, where the neurohormone bursicon interacts with its complementary G protein-coupled receptor; this receptor drives one of the G-protein subunits to signal further enzyme activity and results in development in the wing, such as apoptosis and growth.{{cite journal | vauthors = Bilousov OO, Katanaev VL, Demydov SV, Kozeretska IA | title = The downregulation of the miniature gene does not replicate miniature loss-of-function phenotypes in Drosophila melanogaster wing to the full extent | journal = TSitologiia I Genetika | volume = 47 | issue = 2 | pages = 77–81 | date = Mar–Apr 2013 | pmid = 23745366 }}
• se: sepia- The eye color of the sepia mutant is sepia, a reddish-brown color. In wild-type flies, ommochromes (brown) and drosopterins (red) give the eyes the typical red color.{{cite journal | vauthors = Kim J, Suh H, Kim S, Kim K, Ahn C, Yim J | title = Identification and characteristics of the structural gene for the Drosophila eye colour mutant sepia, encoding PDA synthase, a member of the omega class glutathione S-transferases | journal = The Biochemical Journal | volume = 398 | issue = 3 | pages = 451–60 | date = September 2006 | pmid = 16712527 | pmc = 1559464 | doi = 10.1042/BJ20060424 }}{{cite journal | vauthors = Grant P, Maga T, Loshakov A, Singhal R, Wali A, Nwankwo J, Baron K, Johnson D | display-authors = 6 | title = An Eye on Trafficking Genes: Identification of Four Eye Color Mutations in Drosophila | journal = G3 | volume = 6 | issue = 10 | pages = 3185–3196 | date = October 2016 | pmid = 27558665 | pmc = 5068940 | doi = 10.1534/g3.116.032508 }} The drosopterins are made via a pathway that involves a pyrimidodiazepine synthase,{{cite journal | vauthors = Wiederrecht GJ, Brown GM | date = 1984 | title = Purification and properties of the enzymes from Drosophila melanogaster that catalyze the conversion of dihydroneopterin triphosphate to the pyrimidodiazepine precursor of the drosopterins | journal = J. Biol. Chem. | volume = 259 | pages = 14121–7 | pmid = 6438092 | issue = 22 | doi = 10.1016/S0021-9258(18)89865-9 | doi-access = free }} which is encoded on chromosome 3L. The gene has a premature stop codon in sepia flies, so that the flies cannot produce the pyrimidodiazepine synthase and thus no red pigment, so that the eyes stay sepia. The sepia allele is recessive and thus offspring from sepia flies and homozygous wild type flies, has red eyes. The sepia phenotype does not depend on the sex of the fly.{{cite web|url=https://www.ukessays.com/essays/biology/investigating-patterns-of-inheritence.php|title=Inheritance Patterns in Drosophila Melanogaster|access-date=26 March 2019}}
• v: vermilion- The vermilion mutants cannot produce the brown ommochromes leaving the red drosopterins so that the eyes are vermilion colored (a radiant red) compared to a wild-type D. melanogaster. The vermilion mutation is sex-linked and recessive. The gene that is defect lies on the X chromosome.{{cite journal | vauthors = Green MM | title = Mutant Isoalleles at the Vermilion Locus in Drosophila Melanogaster | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 38 | issue = 4 | pages = 300–5 | date = April 1952 | pmid = 16589094 | pmc = 1063551 | doi = 10.1073/pnas.38.4.300 | bibcode = 1952PNAS...38..300G | doi-access = free }} The brown ommochromes are synthesised from kynurenine, which is made from tryptophane. Vermilion flies cannot convert tryptophane into kynurenine and thus cannot make ommochromes, either. Vermilion mutants live longer than wild-type flies. This longer life span may be associated with the reduced amount of tryptophan converted to kynurenine in vermilion flies.{{cite journal | vauthors = Oxenkrug GF | title = The extended life span of Drosophila melanogaster eye-color (white and vermilion) mutants with impaired formation of kynurenine | journal = Journal of Neural Transmission | volume = 117 | issue = 1 | pages = 23–26 | date = January 2010 | pmid = 19941150 | pmc = 3013506 | doi = 10.1007/s00702-009-0341-7 }}

File:Black Body Mutation Drosophila melanogaster male.jpg

• vg: vestigial- A spontaneous mutation, discovered in 1919 by Thomas Morgan and Calvin Bridges. Vestigial wings are those not fully developed and that have lost function. Since the discovery of the vestigial gene in Drosophila melanogaster, there have been many discoveries of the vestigial gene in other vertebrates and their functions within the vertebrates.{{cite journal | vauthors = Simon E, Faucheux C, Zider A, Thézé N, Thiébaud P | s2cid = 16651247 | title = From vestigial to vestigial-like: the Drosophila gene that has taken wing | journal = Development Genes and Evolution | volume = 226 | issue = 4 | pages = 297–315 | date = July 2016 | pmid = 27116603 | doi = 10.1007/s00427-016-0546-3 }} The vestigial gene is considered to be one of the most important genes for wing formation, but when it becomes over expressed the issue of ectopic wings begin to form.{{cite journal | vauthors = Tomoyasu Y, Ohde T, Clark-Hachtel C | title = What serial homologs can tell us about the origin of insect wings | journal = F1000Research | volume = 6 | page = 268 | date = 2017-03-14 | pmid = 28357056 | pmc = 5357031 | doi = 10.12688/f1000research.10285.1 | doi-access = free }} The vestigial gene acts to regulate the expression of the wing imaginal discs in the embryo and acts with other genes to regulate the development of the wings. A mutated vestigial allele removes an essential sequence of the DNA required for correct development of the wings.{{cite journal | vauthors = Williams JA, Bell JB, Carroll SB | title = Control of Drosophila wing and haltere development by the nuclear vestigial gene product | journal = Genes & Development | volume = 5 | issue = 12B | pages = 2481–95 | date = December 1991 | pmid = 1752439 | doi = 10.1101/gad.5.12b.2481 | doi-access = free }}
• w: white- Drosophila melanogaster wild type typically expresses a brick red eye color. The white eye mutation in fruit flies is caused due to the absence of two pigments associated with red and brown eye colors; peridines (red) and ommochromes (brown). In January 1910, Thomas Hunt Morgan first discovered the white gene and denoted it as w. The discovery of the white-eye mutation by Morgan brought about the beginnings of genetic experimentation and analysis of Drosophila melanogaster. Hunt eventually discovered that the gene followed a similar pattern of inheritance related to the meiotic segregation of the X chromosome. He discovered that the gene was located on the X chromosome with this information. This led to the discovery of sex-linked genes and also to the discovery of other mutations in Drosophila melanogaster.{{cite journal | vauthors = Green MM | title = 2010: A century of Drosophila genetics through the prism of the white gene | journal = Genetics| volume = 184 | issue = 1 | pages = 3–7 | date = January 2010 | pmid = 20061564 | pmc = 2815926 | doi = 10.1534/genetics.109.110015 }} The white-eye mutation leads to several disadvantages in flies, such as a reduced climbing ability, shortened life span, and lowered resistance to stress when compared to wild type flies.{{cite journal | vauthors = Ferreiro MJ, Pérez C, Marchesano M, Ruiz S, Caputi A, Aguilera P, Barrio R, Cantera R | display-authors = 6 | title = rosophila melanogaster White Mutant w1118 Undergo Retinal Degeneration. | journal = Frontiers in Neuroscience | volume = 11 | page = 732 | year = 2018 | pmid = 29354028 | pmc = 5758589 | doi = 10.3389/fnins.2017.00732 | doi-access = free }} Drosophila melanogaster has a series of mating behaviors that enable them to copulate within a given environment and therefore contribute to their fitness. After Morgan's discovery of the white-eye mutation being sex-linked, a study led by Sturtevant (1915) concluded that white-eyed males were less successful than wild-type males in terms of mating with females.{{cite journal | vauthors = Xiao C, Qiu S, Robertson RM | title = The white gene controls copulation success in Drosophila melanogaster | journal = Scientific Reports | volume = 7 | issue = 1 | page = 7712 | date = August 2017 | pmid = 28794482 | pmc = 5550479 | doi = 10.1038/s41598-017-08155-y | doi-access = free | bibcode = 2017NatSR...7.7712X }} It was found that the greater the density in eye pigmentation, the greater the success in mating for the males of Drosophila melanogaster.
• y: yellow- The yellow gene is a genetic mutation known as Dmel\y within the widely used data base called FlyBase. This mutation can be easily identified by the atypical yellow pigment observed in the cuticle of the adult flies and the mouth pieces of the larva.{{cite web|url=http://flybase.org/reports/FBgn0004034.html|title=Gene:Dmel\y|website=Flybase.org|publisher=The FlyBase Consortium|access-date=26 March 2019}} The y mutation comprises the following phenotypic classes: the mutants that show a complete loss of pigmentation from the cuticle (y-type) and other mutants that show a mosaic pigment pattern with some regions of the cuticle (wild type, y2-type).{{cite journal | vauthors = Wittkopp PJ, True JR, Carroll SB | title = Reciprocal functions of the Drosophila yellow and ebony proteins in the development and evolution of pigment patterns | journal = Development | volume = 129 | issue = 8 | pages = 1849–58 | date = April 2002 | doi = 10.1242/dev.129.8.1849 | pmid = 11934851}} The role of the yellow gene is diverse and is responsible for changes in behaviour, sex-specific reproductive maturation and, epigenetic reprogramming.{{cite journal | vauthors = Biessmann H | title = Molecular analysis of the yellow gene (y) region of Drosophila melanogaster | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 82 | issue = 21 | pages = 7369–73 | date = November 1985 | pmid = 3933004 | pmc = 391346 | doi = 10.1073/pnas.82.21.7369 | bibcode = 1985PNAS...82.7369B | doi-access = free }} The y gene is an ideal gene to study as it is visibly clear when an organism has this gene, making it easier to understand the passage of DNA to offspring.

File:Wild-Type vs. Miniature Wings.jpg

{{Infobox genome

| image = Drosophila-chromosome-diagram.jpg

| caption =D. melanogaster chromosomes to scale with megabase-pair references oriented as in the [https://www.ncbi.nlm.nih.gov/mapview/map_search.cgi?taxid=7227 National Center for Biotechnology Information database], centimorgan distances are approximate and estimated from the locations of selected mapped loci.

| taxId = 47

| ploidy = diploid

| chromosomes = 8

| size =

| year = 2015

| organelle =

| organelle-size =

| organelle-year =

}}

The genome of D. melanogaster (sequenced in 2000, and curated at the FlyBase database) contains four pairs of chromosomes – an X/Y pair, and three autosomes labeled 2, 3, and 4. The fourth chromosome is relatively very small and therefore often ignored, aside from its important eyeless gene. The D. melanogaster sequenced genome of 139.5 million base pairs has been annotated{{cite web | title = NCBI (National Center for Biotechnology Information) Genome Database | url = https://www.ncbi.nlm.nih.gov/genome/?term=drosophila%20melanogaster|access-date=2011-11-30}} and contains around 15,682 genes according to Ensemble release 73. More than 60% of the genome appears to be functional non-protein-coding DNA{{cite journal | vauthors = Halligan DL, Keightley PD | title = Ubiquitous selective constraints in the Drosophila genome revealed by a genome-wide interspecies comparison | journal = Genome Research | volume = 16 | issue = 7 | pages = 875–84 | date = July 2006 | pmid = 16751341 | pmc = 1484454 | doi = 10.1101/gr.5022906 }} involved in gene expression control. Determination of sex in Drosophila occurs by the X:A ratio of X chromosomes to autosomes, not because of the presence of a Y chromosome as in human sex determination. Although the Y chromosome is entirely heterochromatic, it contains at least 16 genes, many of which are thought to have male-related functions.{{cite journal | vauthors = Carvalho AB | title = Origin and evolution of the Drosophila Y chromosome | journal = Current Opinion in Genetics & Development | volume = 12 | issue = 6 | pages = 664–8 | date = December 2002 | pmid = 12433579 | doi = 10.1016/S0959-437X(02)00356-8 }}

There are three transferrin orthologs, all of which are dramatically divergent from those known in chordate models.{{cite journal | vauthors = Gabaldón T, Koonin EV | title = Functional and evolutionary implications of gene orthology | journal = Nature Reviews. Genetics | volume = 14 | issue = 5 | pages = 360–366 | date = May 2013 | pmid = 23552219 | pmc = 5877793 | doi = 10.1038/nrg3456 | publisher = Nature Portfolio | author2-link = Eugene Koonin }}

A June 2001 study by National Human Genome Research Institute comparing the fruit fly and human genome estimated that about 60% of genes are conserved between the two species.{{cite web|url=https://www.genome.gov/10005835/|title=Background on Comparative Genomic Analysis|date=December 2002|publisher=US National Human Genome Research Institute}} About 75% of known human disease genes have a recognizable match in the genome of fruit flies,{{cite journal | vauthors = Reiter LT, Potocki L, Chien S, Gribskov M, Bier E | title = A systematic analysis of human disease-associated gene sequences in Drosophila melanogaster | journal = Genome Research | volume = 11 | issue = 6 | pages = 1114–25 | date = June 2001 | pmid = 11381037 | pmc = 311089 | doi = 10.1101/gr.169101 }} and 50% of fly protein sequences have mammalian homologs {{Citation needed|date=January 2020}}. An online database called Homophila is available to search for human disease gene homologues in flies and vice versa.{{cite journal | vauthors = Chien S, Reiter LT, Bier E, Gribskov M | title = Homophila: human disease gene cognates in Drosophila | journal = Nucleic Acids Research | volume = 30 | issue = 1 | pages = 149–51 | date = January 2002 | pmid = 11752278 | pmc = 99119 | doi = 10.1093/nar/30.1.149 }}

Drosophila is being used as a genetic model for several human diseases including the neurodegenerative disorders Parkinson's, Huntington's, spinocerebellar ataxia and Alzheimer's disease.{{cite journal | vauthors = Jaiswal M, Sandoval H, Zhang K, Bayat V, Bellen HJ | title = Probing mechanisms that underlie human neurodegenerative diseases in Drosophila | journal = Annual Review of Genetics | volume = 46 | pages = 371–96 | year = 2012 | pmid = 22974305 | pmc = 3663445 | doi = 10.1146/annurev-genet-110711-155456 }} The fly is also being used to study mechanisms underlying aging and oxidative stress, immunity, diabetes, and cancer, as well as drug abuse.{{cite book|isbn=978-0-12-802905-3|title=Fly Models of Human Diseases. Volume 121 of Current Topics in Developmental Biology|publisher=Academic Press|year=2017 | vauthors = Pick L | url = https://books.google.com/books?id=2zbZCgAAQBAJ }}{{cite journal | vauthors = Buchon N, Silverman N, Cherry S | title = Immunity in Drosophila melanogaster--from microbial recognition to whole-organism physiology | journal = Nature Reviews. Immunology | volume = 14 | issue = 12 | pages = 796–810 | date = December 2014 | pmid = 25421701 | pmc = 6190593 | doi = 10.1038/nri3763 }}{{cite journal | vauthors = Kaun KR, Devineni AV, Heberlein U | title = Drosophila melanogaster as a model to study drug addiction | journal = Human Genetics | volume = 131 | issue = 6 | pages = 959–75 | date = June 2012 | pmid = 22350798 | pmc = 3351628 | doi = 10.1007/s00439-012-1146-6 }}

{{Main|Drosophila embryogenesis}}

The life cycle of this insect has four stages: fertilized egg, larva, pupa, and adult.

Embryogenesis in Drosophila has been extensively studied, as its small size, short generation time, and large brood size makes it ideal for genetic studies. It is also unique among model organisms in that cleavage occurs in a syncytium.

File:Drosophila m oogenesis.png]]

During oogenesis, cytoplasmic bridges called "ring canals" connect the forming oocyte to nurse cells. Nutrients and developmental control molecules move from the nurse cells into the oocyte. In the figure to the left, the forming oocyte can be seen to be covered by follicular support cells.{{cn|date=March 2025}}

After fertilization of the oocyte, the early embryo (or syncytial embryo) undergoes rapid DNA replication and 13 nuclear divisions until about 5000 to 6000 nuclei accumulate in the unseparated cytoplasm of the embryo. By the end of the eighth division, most nuclei have migrated to the surface, surrounding the yolk sac (leaving behind only a few nuclei, which will become the yolk nuclei). After the 10th division, the pole cells form at the posterior end of the embryo, segregating the germ line from the syncytium. Finally, after the 13th division, cell membranes slowly invaginate, dividing the syncytium into individual somatic cells. Once this process is completed, gastrulation starts.{{cite journal | vauthors = Weigmann K, Klapper R, Strasser T, Rickert C, Technau G, Jäckle H, Janning W, Klämbt C | display-authors = 6 | title = FlyMove--a new way to look at development of Drosophila | journal = Trends in Genetics | volume = 19 | issue = 6 | pages = 310–1 | date = June 2003 | pmid = 12801722 | doi = 10.1016/S0168-9525(03)00050-7 }}

Nuclear division in the early Drosophila embryo happens so quickly, no proper checkpoints exist, so mistakes may be made in division of the DNA. To get around this problem, the nuclei that have made a mistake detach from their centrosomes and fall into the centre of the embryo (yolk sac), which will not form part of the fly.{{cn|date=March 2025}}

The gene network (transcriptional and protein interactions) governing the early development of the fruit fly embryo is one of the best understood gene networks to date, especially the patterning along the anteroposterior (AP) and dorsoventral (DV) axes (See under morphogenesis).

The embryo undergoes well-characterized morphogenetic movements during gastrulation and early development, including germ-band extension, formation of several furrows, ventral invagination of the mesoderm, and posterior and anterior invagination of endoderm (gut), as well as extensive body segmentation until finally hatching from the surrounding cuticle into a first-instar larva.{{cn|date=March 2025}}

During larval development, tissues known as imaginal discs grow inside the larva. Imaginal discs develop to form most structures of the adult body, such as the head, legs, wings, thorax, and genitalia. Cells of the imaginal disks are set aside during embryogenesis and continue to grow and divide during the larval stages—unlike most other cells of the larva, which have differentiated to perform specialized functions and grow without further cell division. At metamorphosis, the larva forms a pupa, inside which the larval tissues are reabsorbed and the imaginal tissues undergo extensive morphogenetic movements to form adult structures.

Biotic and abiotic factors experienced during development will affect developmental resource allocation leading to phenotypic variation, also referred to as developmental plasticity.{{cite journal | vauthors = West-Eberhard MJ | title = Developmental plasticity and the origin of species differences | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 102 | issue = suppl 1 | pages = 6543–9 | date = May 2005 | pmid = 15851679 | pmc = 1131862 | doi = 10.1073/pnas.0501844102 | bibcode = 2005PNAS..102.6543W | doi-access = free }} As in all insects,{{cite journal | vauthors = Abram PK, Boivin G, Moiroux J, Brodeur J | title = Behavioural effects of temperature on ectothermic animals: unifying thermal physiology and behavioural plasticity | journal = Biological Reviews of the Cambridge Philosophical Society | volume = 92 | issue = 4 | pages = 1859–1876 | date = November 2017 | pmid = 28980433 | doi = 10.1111/brv.12312 | s2cid = 9099834 }} environmental factors can influence several aspects of development in Drosophila melanogaster.{{cite journal | vauthors = Gibert P, Huey RB, Gilchrist GW | title = Locomotor performance of Drosophila melanogaster: interactions among developmental and adult temperatures, age, and geography | journal = Evolution; International Journal of Organic Evolution | volume = 55 | issue = 1 | pages = 205–9 | date = January 2001 | pmid = 11263741 | doi = 10.1111/j.0014-3820.2001.tb01286.x | s2cid = 2991855 | doi-access = free }}{{Cite journal|vauthors = Zamudio KR, Huey RB, Crill WD |date=1995|title=Bigger isn't always better: body size, developmental and parental temperature and male territorial success in Drosophila melanogaster |journal=Animal Behaviour|language=en|volume=49|issue=3|pages=671–677|doi=10.1016/0003-3472(95)80200-2|s2cid=9124942|issn=0003-3472}} Fruit flies reared under a hypoxia treatment experience decreased thorax length, while hyperoxia produces smaller flight muscles, suggesting negative developmental effects of extreme oxygen levels.{{cite journal | vauthors = Harrison JF, Waters JS, Biddulph TA, Kovacevic A, Klok CJ, Socha JJ | title = Developmental plasticity and stability in the tracheal networks supplying Drosophila flight muscle in response to rearing oxygen level | journal = Journal of Insect Physiology | volume = 106 | issue = Pt 3 | pages = 189–198 | date = April 2018 | pmid = 28927826 | doi = 10.1016/j.jinsphys.2017.09.006 | series = The limits of respiratory function: external and internal constraints on insect gas exchange | doi-access = free | bibcode = 2018JInsP.106..189H }} Circadian rhythms are also subject to developmental plasticity. Light conditions during development affect daily activity patterns in Drosophila melanogaster, where flies raised under constant dark or light are less active as adults than those raised under a 12-hour light/dark cycle.{{cite journal | vauthors = Sheeba V, Chandrashekaran MK, Joshi A, Sharma VK | title = Developmental plasticity of the locomotor activity rhythm of Drosophila melanogaster | journal = Journal of Insect Physiology | volume = 48 | issue = 1 | pages = 25–32 | date = January 2002 | pmid = 12770129 | doi = 10.1016/S0022-1910(01)00139-1 | bibcode = 2002JInsP..48...25S }}

Temperature is one of the most pervasive factors influencing arthropod development. In Drosophila melanogaster temperature-induced developmental plasticity can be beneficial and/or detrimental.{{cite journal | vauthors = Crill WD, Huey RB, Gilchrist GW | title = Within- and Between-Generation Effects of Temperature on the Morphology and Physiology of Drosophila Melanogaster | journal = Evolution; International Journal of Organic Evolution | volume = 50 | issue = 3 | pages = 1205–1218 | date = June 1996 | pmid = 28565273 | doi = 10.2307/2410661 | jstor = 2410661 }}{{cite journal | vauthors = David JR, Araripe LO, Chakir M, Legout H, Lemos B, Pétavy G, Rohmer C, Joly D, Moreteau B | display-authors = 6 | title = Male sterility at extreme temperatures: a significant but neglected phenomenon for understanding Drosophila climatic adaptations | journal = Journal of Evolutionary Biology | volume = 18 | issue = 4 | pages = 838–46 | date = July 2005 | pmid = 16033555 | doi = 10.1111/j.1420-9101.2005.00914.x | s2cid = 23847613 | doi-access = free }} Most often lower developmental temperatures reduce growth rates which influence many other physiological factors.{{cite journal | vauthors = French V, Feast M, Partridge L | title = Body size and cell size in Drosophila: the developmental response to temperature | journal = Journal of Insect Physiology | volume = 44 | issue = 11 | pages = 1081–1089 | date = November 1998 | pmid = 12770407 | doi = 10.1016/S0022-1910(98)00061-4 | bibcode = 1998JInsP..44.1081F }} For example, development at 25 °C increases walking speed, [https://www.researchgate.net/figure/General-shape-of-a-thermal-performance-curve-Relationship-between-environmental_fig1_221716210 thermal performance breadth], and territorial success, while development at 18 °C increases body mass, wing size, all of which are tied to fitness. Moreover, developing at certain low temperatures produces proportionally large wings which improve flight and reproductive performance at similarly low temperatures (See acclimation).{{cite journal | vauthors = Frazier MR, Harrison JF, Kirkton SD, Roberts SP | title = Cold rearing improves cold-flight performance in Drosophila via changes in wing morphology | journal = The Journal of Experimental Biology | volume = 211 | issue = Pt 13 | pages = 2116–22 | date = July 2008 | pmid = 18552301 | doi = 10.1242/jeb.019422 | doi-access = free }}

While certain effects of developmental temperature, like body size, are irreversible in ectotherms, others can be reversible.{{cite journal | vauthors = Slotsbo S, Schou MF, Kristensen TN, Loeschcke V, Sørensen JG | title = Reversibility of developmental heat and cold plasticity is asymmetric and has long-lasting consequences for adult thermal tolerance | journal = The Journal of Experimental Biology | volume = 219 | issue = Pt 17 | pages = 2726–32 | date = September 2016 | pmid = 27353229 | doi = 10.1242/jeb.143750 | doi-access = free }} When Drosophila melanogaster develop at cold temperatures they will have greater cold tolerance, but if cold-reared flies are maintained at warmer temperatures their cold tolerance decreases and heat tolerance increases over time.{{cite journal | vauthors = Gilchrist GW, Huey RB | title = Parental and developmental temperature effects on the thermal dependence of fitness in Drosophila melanogaster | journal = Evolution; International Journal of Organic Evolution | volume = 55 | issue = 1 | pages = 209–14 | date = January 2001 | pmid = 11263742 | doi = 10.1111/j.0014-3820.2001.tb01287.x | s2cid = 1329035 | doi-access = free }} Because insects typically only mate in a specific range of temperatures, their cold/heat tolerance is an important trait in maximizing reproductive output.{{cite journal | vauthors = Austin CJ, Moehring AJ | title = Optimal temperature range of a plastic species, Drosophila simulans | journal = The Journal of Animal Ecology | volume = 82 | issue = 3 | pages = 663–72 | date = May 2013 | pmid = 23360477 | doi = 10.1111/1365-2656.12041 | bibcode = 2013JAnEc..82..663A | doi-access = free }}

While the traits described above are expected to manifest similarly across sexes, developmental temperature can also produce sex-specific effects in D. melanogaster adults.

• Females- Ovariole number is significantly affected by developmental temperature in D. melanogaster.{{cite journal | vauthors = Hodin J, Riddiford LM | title = Different mechanisms underlie phenotypic plasticity and interspecific variation for a reproductive character in drosophilids (Insecta: Diptera) | journal = Evolution; International Journal of Organic Evolution | volume = 54 | issue = 5 | pages = 1638–53 | date = October 2000 | pmid = 11108591 | doi = 10.1111/j.0014-3820.2000.tb00708.x | s2cid = 6875815 | doi-access = free }} Egg size is also affected by developmental temperature, and exacerbated when both parents develop at warm temperatures (See Maternal effect). Under stressful temperatures, these structures will develop to smaller ultimate sizes and decrease a female's reproductive output. Early fecundity (total eggs laid in first 10 days post-eclosion) is maximized when reared at 25 °C (versus 17 °C and 29 °C) regardless of adult temperature.{{cite journal | vauthors = Klepsatel P, Girish TN, Dircksen H, Gáliková M | title = Drosophila is maximised by optimal developmental temperature | journal = The Journal of Experimental Biology | volume = 222 | issue = Pt 10 | pages = jeb202184 | date = May 2019 | pmid = 31064855 | doi = 10.1242/jeb.202184 | doi-access = free }} Across a wide range of developmental temperatures, females tend to have greater heat tolerance than males.{{cite journal | vauthors = Schou MF, Kristensen TN, Pedersen A, Karlsson BG, Loeschcke V, Malmendal A | title = Metabolic and functional characterization of effects of developmental temperature in Drosophila melanogaster | journal = American Journal of Physiology. Regulatory, Integrative and Comparative Physiology | volume = 312 | issue = 2 | pages = R211–R222 | date = February 2017 | pmid = 27927623 | pmc = 5336569 | doi = 10.1152/ajpregu.00268.2016 }}
• Males- Stressful developmental temperatures will cause sterility in D. melanogaster males; although the upper temperature limit can be increased by maintaining strains at high temperatures (See acclimation). Male sterility can be reversible if adults are returned to an optimal temperature after developing at stressful temperatures.{{cite journal | vauthors = Cohet Y, David J | title = Control of the adult reproductive potential by preimaginal thermal conditions: A study in Drosophila melanogaster | journal = Oecologia | volume = 36 | issue = 3 | pages = 295–306 | date = January 1978 | pmid = 28309916 | doi = 10.1007/BF00348055 | s2cid = 12465060 | bibcode = 1978Oecol..36..295C }} Male flies are smaller and more successful at defending food/oviposition sites when reared at 25 °C versus 18 °C; thus smaller males will have increased mating success and reproductive output.

Drosophila flies have both X and Y chromosomes, as well as autosomes. Unlike humans, the Y chromosome does not confer maleness; rather, it encodes genes necessary for making sperm. Sex is instead determined by the ratio of X chromosomes to autosomes.{{cite journal | vauthors = Rideout EJ, Narsaiya MS, Grewal SS | title = The Sex Determination Gene transformer Regulates Male-Female Differences in Drosophila Body Size | journal = PLOS Genetics | volume = 11 | issue = 12 | pages = e1005683 | date = December 2015 | pmid = 26710087 | pmc = 4692505 | doi = 10.1371/journal.pgen.1005683 | doi-access = free }} Furthermore, each cell "decides" whether to be male or female independently of the rest of the organism, resulting in the occasional occurrence of gynandromorphs.

Three major genes are involved in determination of Drosophila sex. These are sex-lethal, sisterless, and deadpan. Deadpan is an autosomal gene which inhibits sex-lethal, while sisterless is carried on the X chromosome and inhibits the action of deadpan. An AAX cell has twice as much deadpan as sisterless, so sex-lethal will be inhibited, creating a male. However, an AAXX cell will produce enough sisterless to inhibit the action of deadpan, allowing the sex-lethal gene to be transcribed to create a female.

Later, control by deadpan and sisterless disappears and what becomes important is the form of the sex-lethal gene. A secondary promoter causes transcription in both males and females. Analysis of the cDNA has shown that different forms are expressed in males and females. Sex-lethal has been shown to affect the splicing of its own mRNA. In males, the third exon is included which encodes a stop codon, causing a truncated form to be produced. In the female version, the presence of sex-lethal causes this exon to be missed out; the other seven amino acids are produced as a full peptide chain, again giving a difference between males and females.{{cite book | vauthors = Gilbert SF | title = Developmental Biology | url = https://archive.org/details/developmentalbio00gilb | url-access = registration | edition = 6th | location = Sunderland (MA) | publisher = Sinauer Associates; 2000 |year=2000 | isbn = 978-0-87893-243-6 }}

Presence or absence of functional sex-lethal proteins now go on to affect the transcription of another protein known as doublesex. In the absence of sex-lethal, doublesex will have the fourth exon removed and be translated up to and including exon 6 (DSX-M[ale]), while in its presence the fourth exon which encodes a stop codon will produce a truncated version of the protein (DSX-F[emale]). DSX-F causes transcription of Yolk proteins 1 and 2 in somatic cells, which will be pumped into the oocyte on its production.

The D. melanogaster immune system can be divided into two responses: humoral and cell-mediated. The former is a systemic response mediated in large part through the toll and Imd pathways, which are parallel systems for detecting microbes. Other pathways including the stress response pathways JAK-STAT and P38, nutritional signalling via FOXO, and JNK cell death signalling are all involved in key physiological responses to infection. D. melanogaster has an organ called the "fat body", which is analogous to the human liver. The fat body is the primary secretory organ and produces key immune molecules upon infection, such as serine proteases and antimicrobial peptides (AMPs). AMPs are secreted into the hemolymph and bind infectious bacteria and fungi, killing them by forming pores in their cell walls or inhibiting intracellular processes. The cellular immune response instead refers to the direct activity of blood cells (hemocytes) in Drosophila, which are analogous to mammalian monocytes/macrophages. Hemocytes also possess a significant role in mediating humoral immune responses such as the melanization reaction.{{cite journal |vauthors=Lemaitre B, Hoffmann J |date=2007 |title=The host defense of Drosophila melanogaster |url=http://infoscience.epfl.ch/record/151765/files/annurev2Eimmunol2E252E0221062E141615.pdf |journal=Annual Review of Immunology |volume=25 |pages=697–743 |doi=10.1146/annurev.immunol.25.022106.141615 |pmid=17201680}}

The immune response to infection can involve up to 2,423 genes, or 13.7% of the genome. Although the fly's transcriptional response to microbial challenge is highly specific to individual pathogens, Drosophila differentially expresses a core group of 252 genes upon infection with most bacteria. This core group of genes is associated with gene ontology categories such as antimicrobial response, stress response, secretion, neuron-like, reproduction, and metabolism among others.{{cite journal | vauthors = Troha K, Im JH, Revah J, Lazzaro BP, Buchon N | title = Comparative transcriptomics reveals CrebA as a novel regulator of infection tolerance in D. melanogaster | journal = PLOS Pathogens | volume = 14 | issue = 2 | pages = e1006847 | date = February 2018 | pmid = 29394281 | pmc = 5812652 | doi = 10.1371/journal.ppat.1006847 | doi-access = free }}{{cite journal | vauthors = De Gregorio E, Spellman PT, Tzou P, Rubin GM, Lemaitre B | title = The Toll and Imd pathways are the major regulators of the immune response in Drosophila | journal = The EMBO Journal | volume = 21 | issue = 11 | pages = 2568–79 | date = June 2002 | pmid = 12032070 | pmc = 126042 | doi = 10.1093/emboj/21.11.2568 }} Drosophila also possesses several immune mechanisms to both shape the microbiota and prevent excessive immune responses upon detection of microbial stimuli. For instance, secreted PGRPs with amidase activity scavenge and degrade immunostimulatory DAP-type PGN in order to block Imd activation.{{cite journal | vauthors = Paredes JC, Welchman DP, Poidevin M, Lemaitre B | title = Negative regulation by amidase PGRPs shapes the Drosophila antibacterial response and protects the fly from innocuous infection | journal = Immunity | volume = 35 | issue = 5 | pages = 770–9 | date = November 2011 | pmid = 22118526 | doi = 10.1016/j.immuni.2011.09.018 | url = http://infoscience.epfl.ch/record/170470/files/1-s2.0-S1074761311004663-main.pdf | doi-access = free }}

Unlike mammals, Drosophila have innate immunity but lack an adaptive immune response. However, the core elements of this innate immune response are conserved between humans and fruit flies. As a result, the fruit fly offers a useful model of innate immunity for disentangling genetic interactions of signalling and effector function, as flies do not have to contend with interference of adaptive immune mechanisms that could confuse results. Various genetic tools, protocols, and assays make Drosophila a classical model for studying the innate immune system,{{cite journal | vauthors = Troha K, Buchon N | title = Methods for the study of innate immunity in Drosophila melanogaster | journal = Wiley Interdisciplinary Reviews. Developmental Biology | volume = 8 | issue = 5 | pages = e344 | date = September 2019 | pmid = 30993906 | doi = 10.1002/wdev.344 | s2cid = 119527642 }} which has even included immune research on the international space station.{{cite journal | vauthors = Gilbert R, Torres M, Clemens R, Hateley S, Hosamani R, Wade W, Bhattacharya S | title = Drosophila melanogaster infection model | journal = npj Microgravity | volume = 6 | issue = 1 | page = 4 | date = February 2020 | pmid = 32047838 | pmc = 7000411 | doi = 10.1038/s41526-019-0091-2 }}

Multiple elements of the Drosophila JAK-STAT signalling pathway bear direct homology to human JAK-STAT pathway genes. JAK-STAT signalling is induced upon various organismal stresses such as heat stress, dehydration, or infection. JAK-STAT induction leads to the production of a number of stress response proteins including Thioester-containing proteins (TEPs),{{cite journal | vauthors = Dostálová A, Rommelaere S, Poidevin M, Lemaitre B | title = Thioester-containing proteins regulate the Toll pathway and play a role in Drosophila defence against microbial pathogens and parasitoid wasps | journal = BMC Biology | volume = 15 | issue = 1 | page = 79 | date = September 2017 | pmid = 28874153 | pmc = 5584532 | doi = 10.1186/s12915-017-0408-0 | doi-access = free }} Turandots,{{cite journal | vauthors = Srinivasan N, Gordon O, Ahrens S, Franz A, Deddouche S, Chakravarty P, Phillips D, Yunus AA, Rosen MK, Valente RS, Teixeira L, Thompson B, Dionne MS, Wood W, Reis e Sousa C | display-authors = 6 | title = Drosophila melanogaster | journal = eLife | volume = 5 | date = November 2016 | pmid = 27871362 | pmc = 5138034 | doi = 10.7554/eLife.19662 | doi-access = free }} and the putative antimicrobial peptide Listericin.{{cite journal | vauthors = Goto A, Yano T, Terashima J, Iwashita S, Oshima Y, Kurata S | title = Cooperative regulation of the induction of the novel antibacterial Listericin by peptidoglycan recognition protein LE and the JAK-STAT pathway | journal = The Journal of Biological Chemistry | volume = 285 | issue = 21 | pages = 15731–8 | date = May 2010 | pmid = 20348097 | pmc = 2871439 | doi = 10.1074/jbc.M109.082115 | doi-access = free }} The mechanisms through which many of these proteins act is still under investigation. For instance, the TEPs appear to promote phagocytosis of Gram-positive bacteria and the induction of the toll pathway. As a consequence, flies lacking TEPs are susceptible to infection by toll pathway challenges.

File:Drosophila-Embryos-as-Model-Systems-for-Monitoring-Bacterial-Infection-in-Real-Time-ppat.1000518.s001.ogv bacteria (red)]]

Circulating hemocytes are key regulators of infection. This has been demonstrated both through genetic tools to generate flies lacking hemocytes, or through injecting microglass beads or lipid droplets that saturate hemocyte ability to phagocytose a secondary infection.{{cite journal | vauthors = Wang L, Kounatidis I, Ligoxygakis P | title = Drosophila as a model to study the role of blood cells in inflammation, innate immunity and cancer | journal = Frontiers in Cellular and Infection Microbiology | volume = 3 | page = 113 | date = January 2014 | pmid = 24409421 | pmc = 3885817 | doi = 10.3389/fcimb.2013.00113 | doi-access = free }}{{cite journal | vauthors = Neyen C, Bretscher AJ, Binggeli O, Lemaitre B | title = Methods to study Drosophila immunity | journal = Methods | volume = 68 | issue = 1 | pages = 116–28 | date = June 2014 | pmid = 24631888 | doi = 10.1016/j.ymeth.2014.02.023 | url = http://infoscience.epfl.ch/record/201328/files/1-s2.0-S104620231400067X-main.pdf }} Flies treated like this fail to phagocytose bacteria upon infection, and are correspondingly susceptible to infection.{{cite journal | vauthors = Hashimoto Y, Tabuchi Y, Sakurai K, Kutsuna M, Kurokawa K, Awasaki T, Sekimizu K, Nakanishi Y, Shiratsuchi A | display-authors = 6 | title = Identification of lipoteichoic acid as a ligand for draper in the phagocytosis of Staphylococcus aureus by Drosophila hemocytes | journal = Journal of Immunology | volume = 183 | issue = 11 | pages = 7451–60 | date = December 2009 | pmid = 19890048 | doi = 10.4049/jimmunol.0901032 | doi-access = free }} These hemocytes derive from two waves of hematopoiesis, one occurring in the early embryo and one occurring during development from larva to adult.{{cite journal | vauthors = Holz A, Bossinger B, Strasser T, Janning W, Klapper R | title = The two origins of hemocytes in Drosophila | journal = Development | volume = 130 | issue = 20 | pages = 4955–62 | date = October 2003 | pmid = 12930778 | doi = 10.1242/dev.00702 | doi-access = free }} However Drosophila hemocytes do not renew over the adult lifespan, and so the fly has a finite number of hemocytes that decrease over the course of its lifespan.{{cite journal | vauthors = Sanchez Bosch P, Makhijani K, Herboso L, Gold KS, Baginsky R, Woodcock KJ, Alexander B, Kukar K, Corcoran S, Jacobs T, Ouyang D, Wong C, Ramond EJ, Rhiner C, Moreno E, Lemaitre B, Geissmann F, Brückner K | display-authors = 6 | title = Adult Drosophila Lack Hematopoiesis but Rely on a Blood Cell Reservoir at the Respiratory Epithelia to Relay Infection Signals to Surrounding Tissues | journal = Developmental Cell | volume = 51 | issue = 6 | pages = 787–803.e5 | date = December 2019 | pmid = 31735669 | pmc = 7263735 | doi = 10.1016/j.devcel.2019.10.017 }} Hemocytes are also involved in regulating cell-cycle events and apoptosis of aberrant tissue (e.g. cancerous cells) by producing Eiger, a tumor necrosis factor signalling molecule that promotes JNK signalling and ultimately cell death and apoptosis.{{cite journal | vauthors = Parvy JP, Yu Y, Dostalova A, Kondo S, Kurjan A, Bulet P, Lemaître B, Vidal M, Cordero JB | display-authors = 6 | title = Drosophila | journal = eLife | volume = 8 | pages = e45061 | date = July 2019 | pmid = 31358113 | pmc = 6667213 | doi = 10.7554/eLife.45061 | doi-access = free }}

In 1971, Ron Konopka and Seymour Benzer published "Clock mutants of Drosophila melanogaster", a paper describing the first mutations that affected an animal's behavior. Wild-type flies show an activity rhythm with a frequency of about a day (24 hours). They found mutants with faster and slower rhythms, as well as broken rhythms—flies that move and rest in random spurts. Work over the following 30 years has shown that these mutations (and others like them) affect a group of genes and their products that form a biochemical or biological clock. This clock is found in a wide range of fly cells, but the clock-bearing cells that control activity are several dozen neurons in the fly's central brain.{{cn|date=March 2025}}

Since then, Benzer and others have used behavioral screens to isolate genes involved in vision, olfaction, audition, learning/memory, courtship, pain, and other processes, such as longevity.{{cn|date=March 2025}}

Following the pioneering work of Alfred Henry Sturtevant{{Cite journal | vauthors = Sturtevant AH | date = 1929 | title = The claret mutant type of Drosophila simulans: a study of chromosome elimination and cell-lineage | journal=Zeitschrift für Wissenschaftliche Zoologie|volume=135|pages=323–356}} and others, Benzer and colleagues used sexual mosaics to develop a novel fate mapping technique. This technique made it possible to assign a particular characteristic to a specific anatomical location. For example, this technique showed that male courtship behavior is controlled by the brain. Mosaic fate mapping also provided the first indication of the existence of pheromones in this species.{{cite journal | vauthors = Nissani M | title = A new behavioral bioassay for an analysis of sexual attraction and pheromones in insects | journal = The Journal of Experimental Zoology | volume = 192 | issue = 2 | pages = 271–5 | date = May 1975 | pmid = 805823 | doi = 10.1002/jez.1401920217 | bibcode = 1975JEZ...192..271N | url = https://www.researchgate.net/publication/22347715 }} Males distinguish between conspecific males and females and direct persistent courtship preferentially toward females thanks to a female-specific sex pheromone which is mostly produced by the female's tergites.

The first learning and memory mutants (dunce, rutabaga, etc.) were isolated by William "Chip" Quinn while in Benzer's lab, and were eventually shown to encode components of an intracellular signaling pathway involving cyclic AMP, protein kinase A, and a transcription factor known as CREB. These molecules were shown to be also involved in synaptic plasticity in Aplysia and mammals.{{Cite book|title=Biotechnology Fundamentals| vauthors = Khan FA |publisher=CRC Press|year=2011|isbn=978-1-4398-2009-4|page=213}}

The Nobel Prize in Physiology or Medicine for 2017 was awarded to Jeffrey C. Hall, Michael Rosbash, Michael W. Young for their works using fruit flies in understanding the "molecular mechanisms controlling the circadian rhythm".{{cite web|url=https://www.nobelprize.org/nobel_prizes/medicine/laureates/2017/press.html|title=The 2017 Nobel Prize in Physiology or Medicine jointly to Jeffrey C. Hall, Michael Rosbash and Michael W. Young for their discoveries of molecular mechanisms controlling the circadian rhythm|publisher=Nobelprize.org|date=2 October 2017|access-date=5 October 2017}}

Male flies sing to the females during courtship using their wings to generate sound, and some of the genetics of sexual behavior have been characterized. In particular, the fruitless gene has several different splice forms, and male flies expressing female splice forms have female-like behavior and vice versa. The TRP channels nompC, nanchung, and inactive are expressed in sound-sensitive Johnston's organ neurons and participate in the transduction of sound.{{cite journal | vauthors = Lehnert BP, Baker AE, Gaudry Q, Chiang AS, Wilson RI | title = Distinct roles of TRP channels in auditory transduction and amplification in Drosophila | journal = Neuron | volume = 77 | issue = 1 | pages = 115–28 | date = January 2013 | pmid = 23312520 | pmc = 3811118 | doi = 10.1016/j.neuron.2012.11.030 }}{{cite journal | vauthors = Zhang W, Yan Z, Jan LY, Jan YN | title = Sound response mediated by the TRP channels NOMPC, NANCHUNG, and INACTIVE in chordotonal organs of Drosophila larvae | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 110 | issue = 33 | pages = 13612–7 | date = August 2013 | pmid = 23898199 | pmc = 3746866 | doi = 10.1073/pnas.1312477110 | bibcode = 2013PNAS..11013612Z | doi-access = free }} Mutating the Genderblind gene, also known as CG6070, alters the sexual behavior of Drosophila, turning the flies bisexual.[http://www.livescience.com/animals/071209-fly-genes.html "Homosexuality Turned On and Off in Fruit Flies"]

File:FruitFly macrogiants B.jpg

Flies use a modified version of Bloom filters to detect novelty of odors, with additional features including similarity of novel odor to that of previously experienced examples, and time elapsed since previous experience of the same odor.{{cite journal | vauthors = Dasgupta S, Sheehan TC, Stevens CF, Navlakha S | title = A neural data structure for novelty detection | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 115 | issue = 51 | pages = 13093–13098 | date = December 2018 | pmid = 30509984 | pmc = 6304992 | doi = 10.1073/pnas.1814448115 | bibcode = 2018PNAS..11513093D | doi-access = free }}

As with most insects, aggressive behaviors between male flies commonly occur in the presence of courting a female and when competing for resources. Such behaviors often involve raising wings and legs towards the opponent and attacking with the whole body.{{cite journal | vauthors = Zwarts L, Versteven M, Callaerts P | title = Genetics and neurobiology of aggression in Drosophila | journal = Fly | volume = 6 | issue = 1 | pages = 35–48 | date = 2012-01-01 | pmid = 22513455 | pmc = 3365836 | doi = 10.4161/fly.19249 }} Thus, it often causes wing damage, which reduces their fitness by removing their ability to fly and mate.{{cite journal | vauthors = Davis SM, Thomas AL, Liu L, Campbell IM, Dierick HA | title = Drosophila Using a Screen for Wing Damage | journal = Genetics | volume = 208 | issue = 1 | pages = 273–282 | date = January 2018 | pmid = 29109180 | pmc = 5753862 | doi = 10.1534/genetics.117.300292 }}

In order for aggression to occur, male flies produce sounds to communicate their intent. A 2017 study found that songs promoting aggression contain pulses occurring at longer intervals.{{cite journal | vauthors = Versteven M, Vanden Broeck L, Geurten B, Zwarts L, Decraecker L, Beelen M, Göpfert MC, Heinrich R, Callaerts P | display-authors = 6 | title = Drosophila aggression | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 114 | issue = 8 | pages = 1958–1963 | date = February 2017 | pmid = 28115690 | pmc = 5338383 | doi = 10.1073/pnas.1605946114 | doi-access = free }} RNA sequencing from fly mutants displaying over-aggressive behaviors found more than 50 auditory-related genes (important for transient receptor potentials, Ca²⁺ signaling, and mechanoreceptor potentials) to be upregulated in the AB neurons located in Johnston's organ. In addition, aggression levels were reduced when these genes were knocked out via RNA interference. This signifies the major role of hearing as a sensory modality in communicating aggression.

Other than hearing, another sensory modality that regulates aggression is pheromone signaling, which operates through either the olfactory system or the gustatory system depending on the pheromone.{{cite book | vauthors = Sengupta S, Smith DP | chapter = How Drosophila Detect Volatile Pheromones: Signaling, Circuits, and Behavior | date = 2014 | pmid = 24830032 | url = http://www.ncbi.nlm.nih.gov/books/NBK200999/ | access-date = 2019-05-30 | publisher = CRC Press/Taylor & Francis | isbn = 978-1-4665-5341-5 | series = Frontiers in Neuroscience | title = Neurobiology of Chemical Communication | veditors = Mucignat-Caretta C }} An example is cVA, an anti-aphrodisiac pheromone used by males to mark females after copulation and to deter other males from mating.{{cite journal | vauthors = Laturney M, Billeter JC | title = Drosophila melanogaster females restore their attractiveness after mating by removing male anti-aphrodisiac pheromones | journal = Nature Communications | volume = 7 | issue = 1 | page = 12322 | date = August 2016 | pmid = 27484362 | pmc = 4976142 | doi = 10.1038/ncomms12322 | bibcode = 2016NatCo...712322L }} This male-specific pheromone causes an increase in male-male aggression when detected by another male's gustatory system. However, upon inserting a mutation that makes the flies irresponsive to cVA, no aggressive behaviors were seen.{{cite journal | vauthors = Wang L, Han X, Mehren J, Hiroi M, Billeter JC, Miyamoto T, Amrein H, Levine JD, Anderson DJ | display-authors = 6 | title = Hierarchical chemosensory regulation of male-male social interactions in Drosophila | journal = Nature Neuroscience | volume = 14 | issue = 6 | pages = 757–62 | date = June 2011 | pmid = 21516101 | pmc = 3102769 | doi = 10.1038/nn.2800 }} This shows how there are multiple modalities for promoting aggression in flies.

Specifically, when competing for food, aggression occurs based on amount of food available and is independent of any social interactions between males.{{cite journal | vauthors = Lim RS, Eyjólfsdóttir E, Shin E, Perona P, Anderson DJ | title = How food controls aggression in Drosophila | journal = PLOS ONE | volume = 9 | issue = 8 | pages = e105626 | date = 2014-08-27 | pmid = 25162609 | pmc = 4146546 | doi = 10.1371/journal.pone.0105626 | bibcode = 2014PLoSO...9j5626L | doi-access = free }} Specifically, sucrose was found to stimulate gustatory receptor neurons, which was necessary to stimulate aggression. However, once the amount of food becomes greater than a certain amount, the competition between males lowers. This is possibly due to an over-abundance of food resources. On a larger scale, food was found to determine the boundaries of a territory since flies were observed to be more aggressive at the food's physical perimeter.

However, like most behaviors requiring arousal and wakefulness, aggression was found to be impaired via sleep deprivation. Specifically, this occurs through the impairment of Octopamine and dopamine signaling, which are important pathways for regulating arousal in insects.{{cite journal | vauthors = Erion R, DiAngelo JR, Crocker A, Sehgal A | title = Interaction between sleep and metabolism in Drosophila with altered octopamine signaling | journal = The Journal of Biological Chemistry | volume = 287 | issue = 39 | pages = 32406–14 | date = September 2012 | pmid = 22829591 | pmc = 3463357 | doi = 10.1074/jbc.M112.360875 | doi-access = free }}{{cite journal | vauthors = Kayser MS, Mainwaring B, Yue Z, Sehgal A | title = Sleep deprivation suppresses aggression in Drosophila | journal = eLife | volume = 4 | pages = e07643 | date = July 2015 | pmid = 26216041 | pmc = 4515473 | doi = 10.7554/eLife.07643 | veditors = Griffith LC | doi-access = free }} Due to reduced aggression, sleep-deprived male flies were found to be disadvantaged at mating compared to normal flies. However, when octopamine agonists were administered upon these sleep-deprived flies, aggression levels were seen to be increased and sexual fitness was subsequently restored. Therefore, this finding implicates the importance of sleep in aggression between male flies.

File:Fly eye stereo pair.png

The compound eye of the fruit fly contains 760 unit eyes or ommatidia, and are one of the most advanced among insects. Each ommatidium contains eight photoreceptor cells (R1-8), support cells, pigment cells, and a cornea. Wild-type flies have reddish pigment cells, which serve to absorb excess blue light so the fly is not blinded by ambient light. Eye color genes regulate cellular vesicular transport. The enzymes needed for pigment synthesis are then transported to the cell's pigment granule, which holds pigment precursor molecules.

File:Drosophila melanogaster - top (aka).jpg

File:Drosophila melanogaster - front (aka).jpg

Each photoreceptor cell consists of two main sections, the cell body and the rhabdomere. The cell body contains the nucleus, while the 100-μm-long rhabdomere is made up of toothbrush-like stacks of membrane called microvilli. Each microvillus is 1–2 μm in length and about 60 nm in diameter.{{cite journal | vauthors = Hardie RC, Raghu P | title = Visual transduction in Drosophila | journal = Nature | volume = 413 | issue = 6852 | pages = 186–93 | date = September 2001 | pmid = 11557987 | doi = 10.1038/35093002 | bibcode = 2001Natur.413..186H | s2cid = 4415605 }} The membrane of the rhabdomere is packed with about 100 million opsin molecules, the visual protein that absorbs light. The other visual proteins are also tightly packed into the microvilli, leaving little room for cytoplasm.

File:Arrangement of photoreceptor cells with their opsins in the Drosophila melanogaster omatidium.pngs in a pale and yellow ommatidia of Drosophila melanogaster: The top row shows two of the six outer photoreceptor cells (R1-R6) and the inner R7 and R8 cells. The bottom row shows the different opsins (Rh1, Rh3, Rh4, Rh5, and Rh6) the cells express. Figure from Sharkey et al. (2020).]]

File:Expression of Rhodopsin-1 in Drosophila eye.jpgs R1-R6]]

The genome of Drosophila encodes seven opsins,{{cite journal | vauthors = Feuda R, Goulty M, Zadra N, Gasparetti T, Rosato E, Pisani D, Rizzoli A, Segata N, Ometto L, Stabelli OR | display-authors = 6 | title = Phylogenomics of Opsin Genes in Diptera Reveals Lineage-Specific Events and Contrasting Evolutionary Dynamics in Anopheles and Drosophila | journal = Genome Biology and Evolution | volume = 13 | issue = 8 | pages = evab170 | date = August 2021 | pmid = 34270718 | pmc = 8369074 | doi = 10.1093/gbe/evab170 }} five of those are expressed in the omatidia of the eye. The photoreceptor cells R1-R6 express the opsin Rh1,{{cite journal | vauthors = Harris WA, Stark WS, Walker JA | title = Genetic dissection of the photoreceptor system in the compound eye of Drosophila melanogaster | journal = The Journal of Physiology | volume = 256 | issue = 2 | pages = 415–439 | date = April 1976 | pmid = 16992509 | pmc = 1309314 | doi = 10.1113/jphysiol.1976.sp011331 | s2cid = 45888026 }} which absorbs maximally blue light (around 480 nm),{{cite journal | vauthors = Ostroy SE, Wilson M, Pak WL | title = Drosophila rhodopsin: photochemistry, extraction and differences in the norp AP12 phototransduction mutant | journal = Biochemical and Biophysical Research Communications | volume = 59 | issue = 3 | pages = 960–966 | date = August 1974 | pmid = 4213042 | doi = 10.1016/s0006-291x(74)80073-2 }}{{cite journal | vauthors = Ostroy SE | title = Characteristics of Drosophila rhodopsin in wild-type and norpA vision transduction mutants | journal = The Journal of General Physiology | volume = 72 | issue = 5 | pages = 717–732 | date = November 1978 | pmid = 105082 | pmc = 2228556 | doi = 10.1085/jgp.72.5.717 | s2cid = 5802525 }}{{cite journal | vauthors = Salcedo E, Huber A, Henrich S, Chadwell LV, Chou WH, Paulsen R, Britt SG | title = Blue- and green-absorbing visual pigments of Drosophila: ectopic expression and physiological characterization of the R8 photoreceptor cell-specific Rh5 and Rh6 rhodopsins | journal = The Journal of Neuroscience | volume = 19 | issue = 24 | pages = 10716–10726 | date = December 1999 | pmid = 10594055 | pmc = 6784940 | doi = 10.1523/jneurosci.19-24-10716.1999 | s2cid = 17575850 }} however the R1-R6 cells cover a broader range of the spectrum than an opsin would allow due to a sensitising pigment{{cite journal | vauthors = Kirschfeld K, Franceschini N, Minke B | title = Evidence for a sensitising pigment in fly photoreceptors | journal = Nature | volume = 269 | issue = 5627 | pages = 386–390 | date = September 1977 | pmid = 909585 | doi = 10.1038/269386a0 | s2cid = 28890008 | bibcode = 1977Natur.269..386K }}{{cite journal | vauthors = Minke B, Kirschfeld K | title = The contribution of a sensitizing pigment to the photosensitivity spectra of fly rhodopsin and metarhodopsin | journal = The Journal of General Physiology | volume = 73 | issue = 5 | pages = 517–540 | date = May 1979 | pmid = 458418 | pmc = 2215190 | doi = 10.1085/jgp.73.5.517 | s2cid = 12451748 }} that adds two sensitivity maxima in the UV-range (355 and 370 nm). The R7 cells come in two types with yellow and pale rhabdomeres (R7y and R7p).{{cite journal | vauthors = Kirschfeld K, Feiler R, Franceschini N |title=A photostable pigment within the rhabdomere of fly photoreceptors no. 7 |journal=Journal of Comparative Physiology A |date=1978 |volume=125 |issue=3 |pages=275–284 |doi=10.1007/BF00656606|s2cid=40233531 }}{{cite journal | vauthors = Kirschfeld K, Franceschini N | title = Photostable pigments within the membrane of photoreceptors and their possible role | journal = Biophysics of Structure and Mechanism | volume = 3 | issue = 2 | pages = 191–194 | date = June 1977 | pmid = 890056 | doi = 10.1007/BF00535818 | s2cid = 5846094 }} The pale R7p cells express the opsin Rh3,{{cite journal | vauthors = Zuker CS, Montell C, Jones K, Laverty T, Rubin GM | title = A rhodopsin gene expressed in photoreceptor cell R7 of the Drosophila eye: homologies with other signal-transducing molecules | journal = The Journal of Neuroscience | volume = 7 | issue = 5 | pages = 1550–1557 | date = May 1987 | pmid = 2437266 | pmc = 6568820 | doi = 10.1523/jneurosci.07-05-01550.1987 | s2cid = 1490332 }} which maximally absorbs UV-light (345 nm).{{cite journal | vauthors = Feiler R, Bjornson R, Kirschfeld K, Mismer D, Rubin GM, Smith DP, Socolich M, Zuker CS | display-authors = 6 | title = Ectopic expression of ultraviolet-rhodopsins in the blue photoreceptor cells of Drosophila: visual physiology and photochemistry of transgenic animals | journal = The Journal of Neuroscience | volume = 12 | issue = 10 | pages = 3862–3868 | date = October 1992 | pmid = 1403087 | pmc = 6575971 | doi = 10.1523/jneurosci.12-10-03862.1992 }} The R7p cells are strictly paired with the R8p cells that express Rh5,{{cite journal | vauthors = Chou WH, Hall KJ, Wilson DB, Wideman CL, Townson SM, Chadwell LV, Britt SG | title = Identification of a novel Drosophila opsin reveals specific patterning of the R7 and R8 photoreceptor cells | journal = Neuron | volume = 17 | issue = 6 | pages = 1101–1115 | date = December 1996 | pmid = 8982159 | doi = 10.1016/s0896-6273(00)80243-3 | s2cid = 18294965 | doi-access = free }} which maximally absorbs violet light (437 nm). The other, the yellow R7y cells express a blue-absorbing screening pigment and the opsin Rh4,{{cite journal | vauthors = Montell C, Jones K, Zuker C, Rubin G | title = A second opsin gene expressed in the ultraviolet-sensitive R7 photoreceptor cells of Drosophila melanogaster | journal = The Journal of Neuroscience | volume = 7 | issue = 5 | pages = 1558–1566 | date = May 1987 | pmid = 2952772 | pmc = 6568825 | doi = 10.1523/JNEUROSCI.07-05-01558.1987 | s2cid = 17003459 }} which maximally absorbs UV-light (375 nm). The R7y cells are strictly paired with R8y cells that express Rh6,{{cite journal | vauthors = Huber A, Schulz S, Bentrop J, Groell C, Wolfrum U, Paulsen R | title = Molecular cloning of Drosophila Rh6 rhodopsin: the visual pigment of a subset of R8 photoreceptor cells | journal = FEBS Letters | volume = 406 | issue = 1–2 | pages = 6–10 | date = April 1997 | pmid = 9109375 | doi = 10.1016/s0014-5793(97)00210-x | s2cid = 18368117 }} which maximally absorbs UV-light (508 nm). In a subset of omatidia both R7 and R8 cells express the opsin Rh3.

However, these absorption maxima of the opsins where measured in white eyed flies without screening pigments (Rh3-Rh6), or from the isolated opsin directly (Rh1). Those pigments reduce the light that reaches the opsins depending on the wavelength. Thus in fully pigmented flies, the effective absorption maxima of opsins differs and thus also the sensitivity of their photoreceptor cells. With screening pigment, the opsin Rh3 is short wave shifted from 345 nm{{efn|Sharkey et al. give the absorption maximum of Rh3 as 334 nm in their result section. However, in the introduction and the material and methods section they give it as 345 nm. For both values, they cite Feiler et al., who reported 345 nm only. Therefore, this seems to be a mistake and they probably meant there 345 nm, too.}} to 330 nm and Rh4 from 375 nm to 355 nm. Whether screening pigment is present does not make a practical difference for the opsin Rh5 (435 nm and 437 nm), while the opsin R6 is long wave shifted by 92 nm from 508 nm to 600 nm.{{cite journal | vauthors = Sharkey CR, Blanco J, Leibowitz MM, Pinto-Benito D, Wardill TJ | title = The spectral sensitivity of Drosophila photoreceptors | journal = Scientific Reports | volume = 10 | issue = 1 | page = 18242 | date = October 2020 | pmid = 33106518 | pmc = 7588446 | doi = 10.1038/s41598-020-74742-1 | s2cid = 215551298 | bibcode = 2020NatSR..1018242S }} 50px Material was copied and adapted from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].

Additionally of the opsins of the eye, Drosophila has two more opsins: The ocelli express the opsin Rh2,{{cite journal | vauthors = Pollock JA, Benzer S | title = Transcript localization of four opsin genes in the three visual organs of Drosophila; RH2 is ocellus specific | journal = Nature | volume = 333 | issue = 6175 | pages = 779–782 | date = June 1988 | pmid = 2968518 | doi = 10.1038/333779a0 | s2cid = 4303934 | bibcode = 1988Natur.333..779P }}{{cite journal | vauthors = Feiler R, Harris WA, Kirschfeld K, Wehrhahn C, Zuker CS | title = Targeted misexpression of a Drosophila opsin gene leads to altered visual function | journal = Nature | volume = 333 | issue = 6175 | pages = 737–741 | date = June 1988 | pmid = 2455230 | doi = 10.1038/333737a0 | s2cid = 4248264 | bibcode = 1988Natur.333..737F }} which maximally absorbs violet light (~420 nm). And the opsin Rh7, which maximally absorbs UV-light (350 nm) with an unusually long wavelength tail up to 500 nm. The long tail disappears if a lysine at position 90 is replaced by glutamic acid. This mutant then absorbs maximally violet light (450 nm).{{cite journal | vauthors = Sakai K, Tsutsui K, Yamashita T, Iwabe N, Takahashi K, Wada A, Shichida Y | title = Drosophila melanogaster rhodopsin Rh7 is a UV-to-visible light sensor with an extraordinarily broad absorption spectrum | journal = Scientific Reports | volume = 7 | issue = 1 | page = 7349 | date = August 2017 | pmid = 28779161 | pmc = 5544684 | doi = 10.1038/s41598-017-07461-9 | s2cid = 3276084 | bibcode = 2017NatSR...7.7349S }} The opsin Rh7 entrains with cryptochrome the circadian rhythm of Drosophila to the day-night-cycle in the central pacemaker neurons.{{cite journal | vauthors = Ni JD, Baik LS, Holmes TC, Montell C | title = A rhodopsin in the brain functions in circadian photoentrainment in Drosophila | journal = Nature | volume = 545 | issue = 7654 | pages = 340–344 | date = May 2017 | pmid = 28489826 | pmc = 5476302 | doi = 10.1038/nature22325 | s2cid = 4468254 | bibcode = 2017Natur.545..340N }}

Each Drosophila opsin binds the carotenoid chromophore 11-cis-3-hydroxyretinal via a lysine.{{cite journal | vauthors = Vogt K |title=The Chromophore of the Visual Pigment in Some Insect Orders |journal=Zeitschrift für Naturforschung C |date=1 February 1984 |volume=39 |issue=1–2 |pages=196–197 |doi=10.1515/znc-1984-1-236|s2cid=88980658 |doi-access=free }}{{cite journal | vauthors = Vogt K, Kirschfeld K |title=Chemical identity of the chromophores of fly visual pigment |journal=Naturwissenschaften |date=April 1984 |volume=71 |issue=4 |pages=211–213 |doi=10.1007/BF00490436|bibcode=1984NW.....71..211V |s2cid=24205801 }} This lysine is conserved in almost all opsins, only a few opsins have lost it during evolution.{{cite journal | vauthors = Gühmann M, Porter ML, Bok MJ | title = The Gluopsins: Opsins without the Retinal Binding Lysine | journal = Cells | volume = 11 | issue = 15 | page = 2441 | date = August 2022 | pmid = 35954284 | pmc = 9368030 | doi = 10.3390/cells11152441 | doi-access = free }} Opsins without it are not light sensitive.{{cite journal | vauthors = Katana R, Guan C, Zanini D, Larsen ME, Giraldo D, Geurten BR, Schmidt CF, Britt SG, Göpfert MC | display-authors = 6 | title = Chromophore-Independent Roles of Opsin Apoproteins in Drosophila Mechanoreceptors | journal = Current Biology | volume = 29 | issue = 17 | pages = 2961–2969.e4 | date = September 2019 | pmid = 31447373 | doi = 10.1016/j.cub.2019.07.036 | s2cid = 201420079 | doi-access = free | bibcode = 2019CBio...29E2961K }}{{cite journal | vauthors = Leung NY, Thakur DP, Gurav AS, Kim SH, Di Pizio A, Niv MY, Montell C | title = Functions of Opsins in Drosophila Taste | journal = Current Biology | volume = 30 | issue = 8 | pages = 1367–1379.e6 | date = April 2020 | pmid = 32243853 | pmc = 7252503 | doi = 10.1016/j.cub.2020.01.068 | bibcode = 2020CBio...30E1367L }}{{cite journal | vauthors = Kumbalasiri T, Rollag MD, Isoldi MC, Castrucci AM, Provencio I | title = Melanopsin triggers the release of internal calcium stores in response to light | journal = Photochemistry and Photobiology | volume = 83 | issue = 2 | pages = 273–279 | date = March 2007 | pmid = 16961436 | doi = 10.1562/2006-07-11-RA-964 | s2cid = 23060331 }} In particular, the Drosophila opsins Rh1, Rh4, and Rh7 function not only as photoreceptors, but also as chemoreceptors for aristolochic acid. These opsins still have the lysine like other opsins. However, if it is replaced by an arginine in Rh1, then Rh1 loses light sensitivity but still responds to aristolochic acid. Thus, the lysine is not needed for Rh1 to function as chemoreceptor.

{{gallery

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|title=Spectral sensitivities of Drosophila melanogaster opsins in photoreceptor cells of white and red eyed flies

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|File:Spectral sensitivities of Drosophila melanogaster opsins in white eyed flies.png

|Spectral sensitivities of Drosophila melanogaster opsins in white eyed flies. The sensitivities of Rh3–R6 are modelled with opsin templates and sensitivity estimates from Salcedo et al. (1999). The opsin Rh1 (redrawn from Salcedo et al.) has a characteristic shape as it is coupled to a UV-sensitising pigment.

|File:Spectral sensitivities of Drosophila melanogaster opsins in red eyed flies.png

|Normalized mean spectral sensitivity curves of Drosophila melanogaster opsins Rh1, Rh3, Rh4, Rh5, and Rh6 measured in their native photoreceptor cells in red eye flies with screening pigment. Each spectral curve is the average from six flies.

}}

{{clear}}

As in vertebrate vision, visual transduction in invertebrates occurs via a G protein-coupled pathway. However, in vertebrates, the G protein is transducin, while the G protein in invertebrates is Gq (dgq in Drosophila). When rhodopsin (Rh) absorbs a photon of light its chromophore, 11-cis-3-hydroxyretinal, is isomerized to all-trans-3-hydroxyretinal. Rh undergoes a conformational change into its active form, metarhodopsin. Metarhodopsin activates Gq, which in turn activates a phospholipase Cβ (PLCβ) known as NorpA.{{cite journal | vauthors = Raghu P, Colley NJ, Webel R, James T, Hasan G, Danin M, Selinger Z, Hardie RC | display-authors = 6 | title = Normal phototransduction in Drosophila photoreceptors lacking an InsP(3) receptor gene | journal = Molecular and Cellular Neurosciences | volume = 15 | issue = 5 | pages = 429–45 | date = May 2000 | pmid = 10833300 | doi = 10.1006/mcne.2000.0846 | s2cid = 23861204 }}

PLCβ hydrolyzes phosphatidylinositol (4,5)-bisphosphate (PIP₂), a phospholipid found in the cell membrane, into soluble inositol triphosphate (IP₃) and diacylglycerol (DAG), which stays in the cell membrane. DAG, a derivative of DAG, or PIP₂ depletion cause a calcium-selective ion channel known as transient receptor potential (TRP) to open and calcium and sodium flows into the cell.{{cite journal | vauthors = Hardie RC, Juusola M | title = Phototransduction in Drosophila | journal = Current Opinion in Neurobiology | volume = 34 | pages = 37–45 | date = October 2015 | pmid = 25638280 | doi = 10.1016/j.conb.2015.01.008 | s2cid = 140206989 | url = https://www.repository.cam.ac.uk/handle/1810/247230 }} IP₃ is thought to bind to IP₃ receptors in the subrhabdomeric cisternae, an extension of the endoplasmic reticulum, and cause release of calcium, but this process does not seem to be essential for normal vision.

Calcium binds to proteins such as calmodulin (CaM) and an eye-specific protein kinase C (PKC) known as InaC. These proteins interact with other proteins and have been shown to be necessary for shut off of the light response. In addition, proteins called arrestins bind metarhodopsin and prevent it from activating more Gq. A sodium-calcium exchanger known as CalX pumps the calcium out of the cell. It uses the inward sodium gradient to export calcium at a stoichiometry of 3 Na⁺/ 1 Ca⁺⁺.{{cite journal | vauthors = Wang T, Xu H, Oberwinkler J, Gu Y, Hardie RC, Montell C | title = Light activation, adaptation, and cell survival functions of the Na+/Ca2+ exchanger CalX | journal = Neuron | volume = 45 | issue = 3 | pages = 367–78 | date = February 2005 | pmid = 15694324 | doi = 10.1016/j.neuron.2004.12.046 | doi-access = free }}

TRP, InaC, and PLC form a signaling complex by binding a scaffolding protein called InaD. InaD contains five binding domains called PDZ domain proteins, which specifically bind the C termini of target proteins. Disruption of the complex by mutations in either the PDZ domains or the target proteins reduces the efficiency of signaling. For example, disruption of the interaction between InaC, the protein kinase C, and InaD results in a delay in inactivation of the light response.

Unlike vertebrate metarhodopsin, invertebrate metarhodopsin can be converted back into rhodopsin by absorbing a photon of orange light (580 nm).

About two-thirds of the Drosophila brain is dedicated to visual processing.{{cite journal | vauthors = Rein K, Zöckler M, Mader MT, Grübel C, Heisenberg M | title = The Drosophila standard brain | journal = Current Biology | volume = 12 | issue = 3 | pages = 227–31 | date = February 2002 | pmid = 11839276 | doi = 10.1016/S0960-9822(02)00656-5 | s2cid = 15785406 | doi-access = free | bibcode = 2002CBio...12..227R }} Although the spatial resolution of their vision is significantly worse than that of humans, their temporal resolution is around 10 times better.

Drosophila are known to exhibit grooming behaviors that are executed in a predictable manner. Drosophila consistently begin a grooming sequence by using their front legs to clean the eyes, then the head and antennae. Using their hind legs, Drosophila proceed to groom their abdomen, and finally the wings and thorax. Throughout this sequence, Drosophila periodically rub their legs together to get rid of excess dust and debris that accumulates during the grooming process.{{cite journal | vauthors = Dawkins R, Dawkins M |title=Hierarchical organization and postural facilitation: rules for grooming in flies |journal=Animal Behaviour |date=1976 |volume=24 |issue=4 |pages=739–755 |doi=10.1016/S0003-3472(76)80003-6|s2cid=53186674 }}

Grooming behaviors have been shown to be executed in a suppression hierarchy. This means that grooming behaviors that occur at the beginning of the sequence prevent those that come later in the sequence from occurring simultaneously, as the grooming sequence consists of mutually exclusive behaviors.{{cite journal | vauthors = Davis WJ |title=Behavioural hierarchies |journal=Trends in Neurosciences |volume=2 |date=1979 |issue=2 |pages=5–7 |doi=10.1016/0166-2236(79)90003-1|s2cid=53180462 }}{{cite journal | vauthors = Seeds AM, Ravbar P, Chung P, Hampel S, Midgley FM, Mensh BD, Simpson JH | title = A suppression hierarchy among competing motor programs drives sequential grooming in Drosophila | journal = eLife | volume = 3 | pages = e02951 | date = August 2014 | pmid = 25139955 | pmc = 4136539 | doi = 10.7554/eLife.02951 | doi-access = free }} This hierarchy does not prevent Drosophila from returning to grooming behaviors that have already been accessed in the grooming sequence. The order of grooming behaviors in the suppression hierarchy is thought to be related to the priority of cleaning a specific body part. For example, the eyes and antennae are likely executed early on in the grooming sequence to prevent debris from interfering with the function of D. melanogaster's sensory organs.

File:Walking drosophila.gif

Like many other hexapod insects, Drosophila typically walk using a tripod gait.{{cite journal | vauthors = Strauss R, Heisenberg M | title = Coordination of legs during straight walking and turning in Drosophila melanogaster | journal = Journal of Comparative Physiology A | volume = 167 | issue = 3 | pages = 403–12 | date = August 1990 | pmid = 2121965 | doi = 10.1007/BF00192575 | s2cid = 12965869 }} This means that three of the legs swing together while the other three remain stationary, or in stance. Specifically, the middle leg moves in phase with the contralateral front and hind legs. However, variability around the tripod configuration exists along a continuum, meaning that flies do not exhibit distinct transitions between different gaits.{{cite journal | vauthors = DeAngelis BD, Zavatone-Veth JA, Clark DA | title = Drosophila | journal = eLife | volume = 8 | date = June 2019 | pmid = 31250807 | pmc = 6598772 | doi = 10.7554/eLife.46409 | doi-access = free }} At fast walking speeds, the walking configuration is mostly tripod (3 legs in stance), but at slower walking speeds, flies are more likely to have four (tetrapod) or five legs in stance (wave).{{cite journal | vauthors = Wosnitza A, Bockemühl T, Dübbert M, Scholz H, Büschges A | title = Inter-leg coordination in the control of walking speed in Drosophila | journal = The Journal of Experimental Biology | volume = 216 | issue = Pt 3 | pages = 480–91 | date = February 2013 | pmid = 23038731 | doi = 10.1242/jeb.078139 | doi-access = free }}{{cite journal | vauthors = Mendes CS, Bartos I, Akay T, Márka S, Mann RS | title = Quantification of gait parameters in freely walking wild type and sensory deprived Drosophila melanogaster | journal = eLife | volume = 2 | pages = e00231 | date = January 2013 | pmid = 23326642 | pmc = 3545443 | doi = 10.7554/eLife.00231 | doi-access = free }} These transitions may help to optimize static stability.{{cite journal | vauthors = Szczecinski NS, Bockemühl T, Chockley AS, Büschges A | title = Drosophila | journal = The Journal of Experimental Biology | volume = 221 | issue = Pt 22 | pages = jeb189142 | date = November 2018 | pmid = 30274987 | doi = 10.1242/jeb.189142 | doi-access = free }} Because flies are so small, inertial forces are negligible compared with the elastic forces of their muscles and joints or the viscous forces of the surrounding air.{{cite journal | vauthors = Hooper SL | title = Body size and the neural control of movement | journal = Current Biology | volume = 22 | issue = 9 | pages = R318-22 | date = May 2012 | pmid = 22575473 | doi = 10.1016/j.cub.2012.02.048 | doi-access = free | bibcode = 2012CBio...22.R318H }}

Flies fly via straight sequences of movement interspersed by rapid turns called saccades. During these turns, a fly is able to rotate 90° in less than 50 milliseconds.

Characteristics of Drosophila flight may be dominated by the viscosity of the air, rather than the inertia of the fly body, but the opposite case with inertia as the dominant force may occur.{{cite journal | vauthors = Fry SN, Sayaman R, Dickinson MH | title = The aerodynamics of free-flight maneuvers in Drosophila | journal = Science | volume = 300 | issue = 5618 | pages = 495–8 | date = April 2003 | pmid = 12702878 | doi = 10.1126/science.1081944 | url = http://www.ini.unizh.ch/~pfmjv/InsectCognition/science_300_495.fly-flight.pdf | bibcode = 2003Sci...300..495F | s2cid = 40952385 | archive-url = https://web.archive.org/web/20150924034953/http://www.ini.unizh.ch/~pfmjv/InsectCognition/science_300_495.fly-flight.pdf | archive-date = 2015-09-24 }} However, subsequent work showed that while the viscous effects on the insect body during flight may be negligible, the aerodynamic forces on the wings themselves actually cause fruit flies' turns to be damped viscously.{{cite journal | vauthors = Hesselberg T, Lehmann FO | title = Turning behaviour depends on frictional damping in the fruit fly Drosophila | journal = The Journal of Experimental Biology | volume = 210 | issue = Pt 24 | pages = 4319–34 | date = December 2007 | pmid = 18055621 | doi = 10.1242/jeb.010389 | doi-access = free }}

{{Main|Drosophila connectome}}

Drosophila is one of the few animals (C. elegans being another) where detailed neural circuits (a connectome) are available.

A high-level connectome, at the level of brain compartments and interconnecting tracts of neurons, exists for the full fly brain.{{cite journal |display-authors=6 |vauthors=Chiang AS, Lin CY, Chuang CC, Chang HM, Hsieh CH, Yeh CW, Shih CT, Wu JJ, Wang GT, Chen YC, Wu CC, Chen GY, Ching YT, Lee PC, Lin CY, Lin HH, Wu CC, Hsu HW, Huang YA, Chen JY, Chiang HJ, Lu CF, Ni RF, Yeh CY, Hwang JK |date=January 2011 |title=Three-dimensional reconstruction of brain-wide wiring networks in Drosophila at single-cell resolution |journal=Current Biology |volume=21 |issue=1 |pages=1–11 |doi=10.1016/j.cub.2010.11.056 |pmid=21129968 |s2cid=17155338 |doi-access=free|bibcode=2011CBio...21....1C }} A version of this is available online.{{cite web |title=FlyCircuit - A Database of Drosophila Brain Neurons |url=http://flycircuit.tw/ |access-date=30 Aug 2013}}

File:FruitFly macrogiants A.jpg

Detailed circuit-level connectomes exist for the lamina{{cite journal |vauthors=Meinertzhagen IA, O'Neil SD |date=March 1991 |title=Synaptic organization of columnar elements in the lamina of the wild type in Drosophila melanogaster |journal=The Journal of Comparative Neurology |volume=305 |issue=2 |pages=232–63 |doi=10.1002/cne.903050206 |pmid=1902848 |s2cid=35301798}}{{cite journal |display-authors=6 |vauthors=Rivera-Alba M, Vitaladevuni SN, Mishchenko Y, Mischenko Y, Lu Z, Takemura SY, Scheffer L, Meinertzhagen IA, Chklovskii DB, de Polavieja GG |date=December 2011 |title=Wiring economy and volume exclusion determine neuronal placement in the Drosophila brain |journal=Current Biology |volume=21 |issue=23 |pages=2000–5 |doi=10.1016/j.cub.2011.10.022 |pmc=3244492 |pmid=22119527|bibcode=2011CBio...21.2000R }} and a medulla{{cite journal |display-authors=6 |vauthors=Takemura SY, Bharioke A, Lu Z, Nern A, Vitaladevuni S, Rivlin PK, Katz WT, Olbris DJ, Plaza SM, Winston P, Zhao T, Horne JA, Fetter RD, Takemura S, Blazek K, Chang LA, Ogundeyi O, Saunders MA, Shapiro V, Sigmund C, Rubin GM, Scheffer LK, Meinertzhagen IA, Chklovskii DB |date=August 2013 |title=A visual motion detection circuit suggested by Drosophila connectomics |journal=Nature |volume=500 |issue=7461 |pages=175–81 |bibcode=2013Natur.500..175T |doi=10.1038/nature12450 |pmc=3799980 |pmid=23925240}} column, both in the visual system of the fruit fly, and the alpha lobe of the mushroom body.{{cite journal |display-authors=6 |vauthors=Takemura SY, Aso Y, Hige T, Wong A, Lu Z, Xu CS, Rivlin PK, Hess H, Zhao T, Parag T, Berg S, Huang G, Katz W, Olbris DJ, Plaza S, Umayam L, Aniceto R, Chang LA, Lauchie S, Ogundeyi O, Ordish C, Shinomiya A, Sigmund C, Takemura S, Tran J, Turner GC, Rubin GM, Scheffer LK |date=July 2017 |title=Drosophila brain |journal=eLife |volume=6 |pages=e26975 |doi=10.7554/eLife.26975 |pmc=5550281 |pmid=28718765 |doi-access=free}}

In May 2017 a paper published in bioRxiv presented an electron microscopy image stack of the whole adult female brain at synaptic resolution. The volume is available for sparse tracing of selected circuits.{{Cite web |title=Entire Fruit Fly Brain Imaged with Electron Microscopy |url=https://www.the-scientist.com/the-scientist/entire-fruit-fly-brain-imaged-with-electron-microscopy-31449 |access-date=2018-07-15 |website=The Scientist Magazine |language=en}}{{cite journal |display-authors=6 |vauthors=Zheng Z, Lauritzen JS, Perlman E, Robinson CG, Nichols M, Milkie D, Torrens O, Price J, Fisher CB, Sharifi N, Calle-Schuler SA, Kmecova L, Ali IJ, Karsh B, Trautman ET, Bogovic JA, Hanslovsky P, Jefferis GS, Kazhdan M, Khairy K, Saalfeld S, Fetter RD, Bock DD |date=July 2018 |title=A Complete Electron Microscopy Volume of the Brain of Adult Drosophila melanogaster |journal=Cell |volume=174 |issue=3 |pages=730–743.e22 |biorxiv=10.1101/140905 |doi=10.1016/j.cell.2018.06.019 |pmc=6063995 |pmid=30033368 |doi-access=free}} Since then, multiple datasets have been collected including a dense connectome of half the central brain of Drosophila in 2020,{{cite journal |vauthors=Xu CS, Januszewski M, Lu Z, Takemura SY, Hayworth K, Huang G, Shinomiya K, Maitin-Shepard J, Ackerman D, Berg S, Blakely T, etal |year=2020 |title=A connectome of the adult Drosophila central brain |journal=bioRxiv |publisher=Cold Spring Harbor Laboratory |pages=2020.01.21.911859 |doi=10.1101/2020.01.21.911859 |s2cid=213140797}}{{Cite web |title=neuPrintExplorer |url=https://neuprint.janelia.org |archive-url=http://web.archive.org/web/20250318081349/https://neuprint.janelia.org/ |archive-date=2025-03-18 |access-date=2025-04-09 |website=neuprint.janelia.org |language=en}} and a dense connectome of the entire female adult nerve cord in 2021.{{Cite journal |last1=Phelps |first1=Jasper S. |last2=Hildebrand |first2=David Grant Colburn |last3=Graham |first3=Brett J. |last4=Kuan |first4=Aaron T. |last5=Thomas |first5=Logan A. |last6=Nguyen |first6=Tri M. |last7=Buhmann |first7=Julia |last8=Azevedo |first8=Anthony W. |last9=Sustar |first9=Anne |last10=Agrawal |first10=Sweta |last11=Liu |first11=Mingguan |last12=Shanny |first12=Brendan L. |last13=Funke |first13=Jan |last14=Tuthill |first14=John C. |last15=Lee |first15=Wei-Chung Allen |date=2021-02-02 |title=Reconstruction of motor control circuits in adult Drosophila using automated transmission electron microscopy |journal=Cell |language=en |volume=184 |issue=3 |pages=759–774.e18 |doi=10.1016/j.cell.2020.12.013 |pmc=8312698 |pmid=33400916}} Generally, these datasets are acquired by sectioning the tissue (e.g. the brain) into thin sections (on order of ten or hundreds of nanometers). Each section is then imaged using an electron microscope and these images are stitched and aligned together to create a 3D image volume. The methods used in reconstruction and initial analysis of the such datasets followed.{{cite journal |vauthors=Scheffer LK, Xu CS, Januszewski M, Lu Z, Takemura SY, Hayworth KJ, Huang G, Shinomiya K, Maitlin-Shepard J, Berg S, Clements J, etal |year=2020 |title=A Connectome and Analysis of the Adult Drosophila Central Brain |journal=bioRxiv |publisher=Cold Spring Harbor |volume=9 |doi=10.1101/2020.04.07.030213 |pmc=7546738 |pmid=32880371 |s2cid=215790785}} Due to advancements in deep learning, automated methods for image segmentation have made large scale reconstruction providing dense reconstructions of all the neurites within the volume.{{Cite bioRxiv |biorxiv=10.1101/2022.03.25.485816 |first1=Sergiy |last1=Popovych |first2=Thomas |last2=Macrina |title=Petascale pipeline for precise alignment of images from serial section electron microscopy |date=2022-03-27 |last3=Kemnitz |first3=Nico |last4=Castro |first4=Manuel |last5=Nehoran |first5=Barak |last6=Jia |first6=Zhen |last7=Bae |first7=J. Alexander |last8=Mitchell |first8=Eric |last9=Mu |first9=Shang |last10=Trautman |first10=Eric T. |last11=Saalfeld |first11=Stephan |last12=Li |first12=Kai |last13=Seung |first13=Sebastian}} Furthermore, the resolution of electron microscopy illuminates ultrastructural variations between neurons as well as the location of individual synapses, thereby providing a wiring diagram of synaptic connectivity between all neurites within the given dataset.

In 2023, the complete map of a Drosophila larval brain at the synapse level, and an analysis of its architecture was published. The larval brain consists of 3016 neurons and 548,000 synaptic sites,{{Cite journal |last1=Winding |first1=Michael |last2=Pedigo |first2=Benjamin D. |last3=Barnes |first3=Christopher L. |last4=Patsolic |first4=Heather G. |last5=Park |first5=Youngser |last6=Kazimiers |first6=Tom |last7=Fushiki |first7=Akira |last8=Andrade |first8=Ingrid V. |last9=Khandelwal |first9=Avinash |last10=Valdes-Aleman |first10=Javier |last11=Li |first11=Feng |last12=Randel |first12=Nadine |last13=Barsotti |first13=Elizabeth |last14=Correia |first14=Ana |last15=Fetter |first15=Richard D. |date=2023-03-10 |title=The connectome of an insect brain |journal=Science |language=en |volume=379 |issue=6636 |pages=eadd9330 |doi=10.1126/science.add9330 |pmc=7614541 |pmid=36893230}} whereas the adult brain has about 150,000 neurons and 150 million synapses.

Drosophila is sometimes referred to as a pest due to its tendency to live in human settlements where fermenting fruit is found. Flies may collect in homes, restaurants, stores, and other locations. The name and behavior of this species of fly have led to the misconception that it is a biological security risk in Australia and elsewhere. While other "fruit fly" species do pose a risk, D. melanogaster is attracted to fruit that is already rotting, rather than causing fruit to rot.{{cite web |url=http://preventfruitfly.com.au/why-is-fruit-fly-a-problem/non-pest-species |title=Non pest species |publisher=Plant Health Australia |access-date=September 19, 2017}}{{cite news | vauthors = McEvey S |date=February 5, 2014 |title=Fruit Flies: A Case Of Mistaken Identity |url=https://australianmuseum.net.au/blogpost/science/fruit-flies-mistaken-identity |publisher=Australian Museum |access-date=September 19, 2017}}

• Animal testing on invertebrates
• Eating behavior in Insects (Measurement)
• Fruit flies in space
• Genetically modified insect
• Gynandromorphism
• JETLAG gene
• List of Drosophila databases
• Spätzle (gene)
• Time flies like an arrow; fruit flies like a banana
• Transgenesis
• Zebrafish – another widely used model organism in scientific research
• Enhancer-FACS-seq

{{Notelist}}

{{Reflist|32em}}

{{Refbegin}}

• {{cite book | vauthors = Kohler RE |title=Lords of the Fly: Drosophila genetics and the experimental life | url = https://archive.org/details/lordsofflydrosop0000kohl | url-access = registration |publisher=University of Chicago Press |location=Chicago |year=1994 |isbn=978-0-226-45063-6 }}
• {{cite book | vauthors = Gilbert SF |title=Developmental Biology. | url = https://archive.org/details/developmentalbio00gilb | url-access = registration | edition = 6th |publisher=Sunderland (MA): Sinauer Associates; 2000 |year=2000 |isbn=978-0-87893-243-6 }}
• {{cite journal | vauthors = Perrimon N, Bonini NM, Dhillon P | title = Fruit flies on the front line: the translational impact of Drosophila | journal = Disease Models & Mechanisms | volume = 9 | issue = 3 | pages = 229–31 | date = March 2016 | pmid = 26935101 | pmc = 4833334 | doi = 10.1242/dmm.024810 }}
• {{cite news | vauthors = Henderson M | date = April 8, 2010 |title=Row over fruit fly Drosophila melanogaster name bugs scientists |url=http://www.theaustralian.com.au/news/world/row-over-fruit-fly-drosophila-melanogaster-name-bugs-scientists/news-story/d95720128e4eb89d00d1917951791cfa |work=The Times |publisher=The Australian |access-date=September 19, 2017}}

{{Refend}}

{{Wikispecies}}

{{Commons}}

{{Scholia|topic}}

• {{cite web|url=http://ceolas.org/VL/fly/intro.html|work= Drosophila Virtual Library|title=A quick and simple introduction to Drosophila melanogaster}}
• [https://dgrc.bio.indiana.edu/Home "Drosophila Genomics Resource Center"] – collects, maintains and distributes Drosophila DNA clones and cell lines.
• [https://bdsc.indiana.edu/ "Bloomington Drosophila Stock Center"] – collects, maintains and distributes Drosophila melanogaster strains for research
• {{cite web|url=http://flybase.net/|title= FlyBase—A Database of Drosophila Genes & Genomes}}
• {{cite web|url=https://www.ncbi.nlm.nih.gov/mapview/map_search.cgi?taxid=7227|title= NCBI Map Viewer – Drosophila melanogaster}}
• {{cite web|url=http://www.ceolas.org/VL/fly/|title=Drosophila Virtual Library}}
• {{cite web|url=http://www.fruitfly.org/ |title=The Berkeley Drosophila Genome Project}}
• {{cite web|url=http://flymove.uni-muenster.de/|title= FlyMove}} – video resources for Drosophila development
• {{cite web|url=http://www.flynome.com/index.html|archive-url=https://web.archive.org/web/20111008192555/http://www.flynome.com/index.html|archive-date=8 October 2011|title= Drosophila Nomenclature—naming of genes}}
• View the [http://www.ensembl.org/Drosophila_melanogaster/Info/Index/ Fruitfly genome] on Ensembl
• {{UCSC genomes|dm6}}
• [http://www.flyfacility.ls.manchester.ac.uk/forthepublic/ Manchester Fly Facility – for the public] {{Webarchive|url=https://web.archive.org/web/20150513014718/http://www.flyfacility.ls.manchester.ac.uk/forthepublic/ |date=2015-05-13 }} from the University of Manchester
• [https://droso4schools.wordpress.com/ The droso4schools website] with school-relevant resources about Drosophila
• [https://www.youtube.com/watch?v=qDbJnFLl3kU Part 1] of the "Small fly: BIG impact" educational videos explaining the history and importance of the model organism Drosophila.
• [https://www.youtube.com/watch?v=C9FSf6nhDSc Part 2] of the "Small fly: BIG impact" educational videos explaining how research is carried out in Drosophila.
• [http://www.thirteen.org/curious/episodes/inside-the-fly-lab/ "Inside the Fly Lab"]—broadcast by WGBH and PBS, in the program series Curious, January 2008.
• [http://whyfiles.org/shorties/285fly_taste/ "How a Fly Detects Poison"] {{Webarchive|url=https://archive.today/20130113123708/http://whyfiles.org/shorties/285fly_taste/ |date=2013-01-13 }}—WhyFiles.org article describes how the fruit fly tastes a larva-killing chemical in food.

{{Model Organisms}}

{{Taxonbar|from=Q130888}}

{{Authority control}}

{{DEFAULTSORT:Drosophila Melanogaster}}

Category:Diptera of North America

Category:Flies and humans

Category:Insect immunity

Category:Insects described in 1830

Category:Insects in culture

Category:Taxa named by Johann Wilhelm Meigen

melanogaster