Macroevolution

After Charles Darwin published his book On the Origin of Species{{Cite book|last=Darwin|first=C.|title=On the origin of species by means of natural selection|publisher=John Murray|year=1859|location=London}} in 1859, evolution was widely accepted to be real phenomenon. However, many scientists still disagreed with Darwin that natural selection was the primary mechanism to explain evolution. Prior to the modern synthesis, during the period between the 1880s to the 1930s (dubbed the ‘Eclipse of Darwinism’) many scientists argued in favor of alternative explanations. These included ‘orthogenesis’, and among its proponents was the Russian entomologist Yuri A. Filipchenko.

Filipchenko appears to have been the one who coined the term ‘macroevolution’ in his book Variabilität und Variation (1927). While introducing the concept, he claimed that the field of genetics is insufficient to explain “the origin of higher systematic units” above the species level.

{{Text and translation

| Auf die Weise hebt die heutige Genetik zweifellos den Schleier von der Evolution der Biotypen, Jordanone und Linneone (eine Art Mikroevolution), dagegen jene Evolution der höheren systematischen Gruppen, welche von jeher die Geister besonders für sich in Anspruch genommen hat (eine Art Makroevolution), liegt gänzlich außerhalb ihres Gesichtsfeldes, und dieser Umstand scheint uns die von uns oben angeführten Erwägungen über das Fehlen einer inneren Beziehung zwischen der Genetik und der Deszendenzlehre, die sich ja hauptsächlich mit der Makroevolution befaßt, nur zu unterstreichen.| In this way, modern genetics undoubtedly lifts the veil from the evolution of biotypes, Jordanones and Linneones [i.e. variations within a species]{{efn|name="BiotJordLinn" | The terms ('biotypes', 'Jordanone', and 'Linneone') used here by Filipchenko were/are rarely used among non-Russian speaking scientists. According to Krasil'nikov (1958),{{cite book |last1=Krasilʹnikov |first1=Nikolaĭ Aleksandrovich |title=Soil microorganisms and higher plants |date=1958 |publisher=Academy of Sciences of the USSR |location=Moscow |url=https://www.soilandhealth.org/wp-content/uploads/01aglibrary/010112.krasilnikov.pdf}} these terms were used to describe the variety of forms observed within a single species: "With the development of genetics the concept of species widened according to the ideas of variability and heredity of organisms. New terms were introduced for the determination of species subdivision, such as "biotype", "pure line", "jardanon", "linneon", etc. ["Jardanon"--a simple means of classification of lower organisms. "Linneon"--the complex of "jardanons"--according to the Russian concept, the inner species variety of forms does not exceed the limits of qualitative unity of the species.]"}} (a kind of microevolution), but that evolution of the higher systematic groups, which has always particularly occupied the minds of men (a kind of macroevolution), lies entirely outside its field of vision, and this circumstance seems to us only to emphasize the considerations we have given above about the lack of an inner relationship between genetics and the theory of descent, which is mainly concerned with macroevolution. | Yuri Filipchenko, Variabilität und Variation (1927), pages 93-94

}}

Filipchenko believed that the origin of families must require the sudden appearance of new traits which are different in greater magnitude compared to the characters required for the origin of a genus or species. However, this view is no longer consistent with contemporary understanding of evolution. Furthermore, the Linnaean ranks of ‘genus’ (and higher) are not real entities but arbitrary concepts.{{cite journal |last1=Hendricks |first1=Jonathan R. |last2=Saupe |first2=Erin E |last3=Myers |first3=Corinne E. |last4=Hermsen |first4=Elizabeth J. |last5=Allmon |first5=Warren D. |title=he generification of the fossil record. |journal=Paleobiology |date=2014 |volume=40 |issue=4 |pages=511–528 |doi=10.1666/13076}}

The term macroevolution was adopted by Filipchenko's protégé Theodosius Dobzhansky in his book ‘Genetics und the Origin of Species’ (1937) and in The Material Basis of Evolution (1940) by the geneticist Richard Goldschmidt, a close friend of Filipchenko. Goldschmidt suggested saltational evolutionary changes{{Cite journal|last=Goldschmidt|first=R.|title=Some aspects of evolution|journal=Science|year=1933|volume=78|issue=2033|pages=539–547|doi=10.1126/science.78.2033.539|pmid=17811930|bibcode=1933Sci....78..539G}}{{Cite book|last=Goldschmidt|first=R.|title=The material basis of evolution|publisher=Yale University Press|year=1940}} which found a moderate revival in the hopeful monster concept of evolutionary developmental biology (or evo-devo).{{Cite journal|last=Theißen|first=Günter|date=March 2009|title=Saltational evolution: hopeful monsters are here to stay|journal=Theory in Biosciences|language=en|volume=128|issue=1|pages=43–51|doi=10.1007/s12064-009-0058-z|pmid=19224263|s2cid=4983539|issn=1431-7613}}{{Cite book|last=Rieppel, Olivier|title=Turtles as hopeful monsters : origins and evolution|date=13 March 2017|isbn=978-0-253-02507-4|location=Bloomington, Indiana|oclc=962141060}} Occasionally such dramatic changes can lead to novel features that survive.

As an alternative to saltational evolution, Dobzhansky{{Cite book|last=Dobzhanski|first=T.|title=Genetics and the origin of species.|publisher=Columbia University Press|year=1937}} suggested that the difference between macroevolution and microevolution reflects essentially a difference in time-scales, and that macroevolutionary changes were simply the sum of microevolutionary changes over geologic time. This view became broadly accepted in the middle of the last century but it has been challenged by a number of scientists who claim that microevolution is necessary but not sufficient to explain macroevolution. This is the decoupled view (see below).

There has been considerable debate regarding the connection between microevolution and macroevolution.

The ‘Extrapolation’ view holds that macroevolution is merely cumulative microevolution.

The ‘Decoupled’ view holds that there are separate macroevolutionary processes that cannot be sufficiently explained by microevolutionary processes alone.{{cite book |last=Ayala Francisco J |date=1983|name-list-style= and |editor-last1 = Asquith | editor-first1= Peter D| editor-last2=Nickles|editor-first2= Thomas |title=PSA 1982 |volume=2|publisher=Philosophy of Science Association |pages=118–132 |chapter=Beyond Darwinism? The Challenge of Macroevolution to the Synthetic Theory of Evolution |isbn=}}{{cite book | vauthors = Levinton Jeffrey S | date = 2001 | title = Genetics, Paleontology, and Macroevolution 2nd edition | publisher = Cambridge University Press | place = Cambridge, UK | isbn = 0-521-80317-9}}{{cite journal |last1=Simons |first1=Andrew M. |title=The continuity of microevolution and macroevolution |journal=Journal of Evolutionary Biology |date=August 21, 2002 |volume=15 |issue=5 |pages=688–701 |doi=10.1046/j.1420-9101.2002.00437.x}}{{cite journal |last1=Erwin |first1=Douglas H. |title=Macroevolution is more than repeated rounds of microevolution |journal=Evolution & Development |date=December 24, 2001 |volume=2 |issue=2 |pages=78–84 |doi=10.1046/j.1525-142x.2000.00045.x|pmid=11258393 }}{{cite journal |last1=Adams |first1=Mark B |title=Filipchenko [Philiptschenko], Iurii Aleksandrovich. |journal=Dictionary of Scientific Biography |date=1990 |volume=17 |issue=297–303 |url=https://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/filipchenko-philiptschenko-iurii-aleksandrovich}}{{cite web |last1=Moran |first1=Laurence A. |title=Macroevolution |url=https://sandwalk.blogspot.com/2022/10/macroevolution.html |website=Sandwalk Blog |date=October 13, 2022}}

Within microevolution, the evolutionary process of changing heritable characteristics (e.g. changes in allele frequencies) is described by population genetics, with mechanisms such as mutation, natural selection, and genetic drift, and speciation (e.g. sympatric and allopatric speciation), phyletic gradualism and punctuated equilibrium. Macroevolution asks how higher taxonomic groups (genera, families, orders, etc) have evolved across geography and vast spans of geological time. Important questions and topics include:

• How different species are related to each other is addressed by phylogenetics.
• The rates of evolutionary change and across time in the fossil record. Why do some groups experience a lot of change while others remain morphologically stable, as in living fossils?{{Cite journal|last1=Kin|first1=Adrian|last2=Błażejowski|first2=Błażej|date=2014-10-02|title=The Horseshoe Crab of the Genus Limulus: Living Fossil or Stabilomorph?|journal=PLOS ONE|language=en|volume=9|issue=10|pages=e108036|doi=10.1371/journal.pone.0108036|issn=1932-6203|pmc=4183490|pmid=25275563|bibcode=2014PLoSO...9j8036K|doi-access=free}}
• Mass extinctions and evolutionary diversifications, e.g. the Permian-Triassic and Cretaceous-Paleogene events, the Cambrian Explosion and Cretaceous Terrestrial Revolution.
• Why different taxonomic groups (even in spite of having similar ages) exhibit different survival/extinction rates, species diversity, and/or morphological disparity.
• Long-term trends in evolution, e.g. trends towards complexity or simplicity.{{cite journal |last1=Gregory |first1=T.R. |title=Evolutionary Trends |journal=Evo Edu Outreach |date=June 25, 2008 |volume=1 |issue=3 |pages=259–273 |doi=10.1007/s12052-008-0055-6 |issn=1936-6434|doi-access=free }}
• How species and higher taxa have evolved, e.g. via gene duplication, heterochrony, novelty in evo-devo, facilitated variation, and constructive neutral evolution.

{{Main|speciation}}

According to the modern definition, the evolutionary transition from the ancestral to the daughter species is microevolutionary, because it results from selection (or, more generally, sorting) among varying organisms. However, speciation has also a macroevolutionary aspect, because it produces the interspecific variation species selection operates on. Another macroevolutionary aspect of speciation is the rate at which it successfully occurs, analogous to reproductive success in microevolution.

Speciation is the process in which populations within one species change to an extent at which they become reproductively isolated, that is, they cannot interbreed anymore. However, this classical concept has been challenged and more recently, a phylogenetic or evolutionary species concept has been adopted. Their main criteria for new species is to be diagnosable and monophyletic, that is, they form a clearly defined lineage.{{Cite journal |last=Luckow |first=Melissa |date=1995 |title=Species Concepts: Assumptions, Methods, and Applications |url=https://www.jstor.org/stable/2419812 |journal=Systematic Botany |volume=20 |issue=4 |pages=589–605 |doi=10.2307/2419812 |jstor=2419812 |issn=0363-6445|url-access=subscription }}{{Cite journal |last1=Frost |first1=Darrel R. |last2=Hillis |first2=David M. |date=1990 |title=Species in Concept and Practice: Herpetological Applications |url=https://www.jstor.org/stable/3892607 |journal=Herpetologica |volume=46 |issue=1 |pages=86–104 |jstor=3892607 |issn=0018-0831}}

Charles Darwin first discovered that speciation can be extrapolated so that species not only evolve into new species, but also into new genera, families and other groups of animals. In other words, macroevolution is reducible to microevolution through selection of traits over long periods of time.{{Cite journal|last=Greenwood|first=P. H.|title=Macroevolution - myth or reality ?|journal=Biological Journal of the Linnean Society|year=1979|volume=12|issue=4|pages=293–304|doi=10.1111/j.1095-8312.1979.tb00061.x}} In addition, some scholars have argued that selection at the species level is important as well.{{Cite journal|last=Grantham|first=T A|date=November 1995|title=Hierarchical Approaches to Macroevolution: Recent Work on Species Selection and the "Effect Hypothesis"|journal=Annual Review of Ecology and Systematics|language=en|volume=26|issue=1|pages=301–321|doi=10.1146/annurev.es.26.110195.001505|bibcode=1995AnRES..26..301G |issn=0066-4162}} The advent of genome sequencing enabled the discovery of gradual genetic changes both during speciation but also across higher taxa. For instance, the evolution of humans from ancestral primates or other mammals can be traced to numerous but individual mutations.{{Cite journal |last1=Foley |first1=Nicole M. |last2=Mason |first2=Victor C. |last3=Harris |first3=Andrew J. |last4=Bredemeyer |first4=Kevin R. |last5=Damas |first5=Joana |last6=Lewin |first6=Harris A. |last7=Eizirik |first7=Eduardo |last8=Gatesy |first8=John |last9=Karlsson |first9=Elinor K. |last10=Lindblad-Toh |first10=Kerstin |last11=Zoonomia Consortium‡ |last12=Springer |first12=Mark S. |last13=Murphy |first13=William J. |last14=Andrews |first14=Gregory |last15=Armstrong |first15=Joel C. |date=2023-04-28 |title=A genomic timescale for placental mammal evolution |journal=Science |language=en |volume=380 |issue=6643 |pages=eabl8189 |doi=10.1126/science.abl8189 |issn=0036-8075 |pmc=10233747 |pmid=37104581}}

One of the main questions in evolutionary biology is how new structures evolve, such as new organs. Macroevolution is often thought to require the evolution of structures that are 'completely new'. However, fundamentally novel structures are not necessary for dramatic evolutionary change. As can be seen in vertebrate evolution, most "new" organs are actually not new—they are simply modifications of previously existing organs. For instance, the evolution of mammal diversity in the past 100 million years has not required any major innovation.{{Cite journal |last1=Meredith |first1=R. W. |last2=Janecka |first2=J. E. |last3=Gatesy |first3=J. |last4=Ryder |first4=O. A. |last5=Fisher |first5=C. A. |last6=Teeling |first6=E. C. |last7=Goodbla |first7=A. |last8=Eizirik |first8=E. |last9=Simao |first9=T. L. L. |last10=Stadler |first10=T. |last11=Rabosky |first11=D. L. |last12=Honeycutt |first12=R. L. |last13=Flynn |first13=J. J. |last14=Ingram |first14=C. M. |last15=Steiner |first15=C. |date=2011-10-28 |title=Impacts of the Cretaceous Terrestrial Revolution and KPg Extinction on Mammal Diversification |url=https://www.sciencemag.org/lookup/doi/10.1126/science.1211028 |journal=Science |language=en |volume=334 |issue=6055 |pages=521–524 |doi=10.1126/science.1211028 |pmid=21940861 |bibcode=2011Sci...334..521M |s2cid=38120449 |issn=0036-8075|url-access=subscription }} All of this diversity can be explained by modification of existing organs, such as the evolution of elephant tusks from incisors. Other examples include wings (modified limbs), feathers (modified reptile scales),{{Cite journal |last1=Wu |first1=Ping |last2=Yan |first2=Jie |last3=Lai |first3=Yung-Chih |last4=Ng |first4=Chen Siang |last5=Li |first5=Ang |last6=Jiang |first6=Xueyuan |last7=Elsey |first7=Ruth M |last8=Widelitz |first8=Randall |last9=Bajpai |first9=Ruchi |last10=Li |first10=Wen-Hsiung |last11=Chuong |first11=Cheng-Ming |date=2017-11-21 |title=Multiple Regulatory Modules Are Required for Scale-to-Feather Conversion |url=|journal=Molecular Biology and Evolution |volume=35 |issue=2 |pages=417–430 |doi=10.1093/molbev/msx295 |issn=0737-4038 |pmc=5850302 |pmid=29177513}} lungs (modified swim bladders, e.g. found in fish),{{Cite journal |last=Brainerd |first=E. L. |date=1999-12-01 |title=New perspectives on the evolution of lung ventilation mechanisms in vertebrates |url=|journal=Experimental Biology Online |language=en |volume=4 |issue=2 |pages=1–28 |doi=10.1007/s00898-999-0002-1 |bibcode=1999EvBO....4b...1B |s2cid=35368264 |issn=1430-3418}}{{Cite journal |last1=Hoffman |first1=M. |last2=Taylor |first2=B. E. |last3=Harris |first3=M. B. |date=2016-04-01 |title=Evolution of lung breathing from a lungless primitive vertebrate |journal=Respiratory Physiology & Neurobiology |series=Physiology of respiratory networks of non-mammalian vertebrates |language=en |volume=224 |pages=11–16 |doi=10.1016/j.resp.2015.09.016 |issn=1569-9048 |pmc=5138057 |pmid=26476056}} or even the heart (a muscularized segment of a vein).{{Cite journal |last1=Jensen |first1=Bjarke |last2=Wang |first2=Tobias |last3=Christoffels |first3=Vincent M. |last4=Moorman |first4=Antoon F. M. |date=2013-04-01 |title=Evolution and development of the building plan of the vertebrate heart |journal=Biochimica et Biophysica Acta (BBA) - Molecular Cell Research |series=Cardiomyocyte Biology: Cardiac Pathways of Differentiation, Metabolism and Contraction |language=en |volume=1833 |issue=4 |pages=783–794 |doi=10.1016/j.bbamcr.2012.10.004 |pmid=23063530 |s2cid=28787569 |issn=0167-4889|doi-access=free }}

The same concept applies to the evolution of "novel" tissues. Even fundamental tissues such as bone can evolve from combining existing proteins (collagen) with calcium phosphate (specifically, hydroxy-apatite). This probably happened when certain cells that make collagen also accumulated calcium phosphate to get a proto-bone cell.{{Cite journal |last1=Wagner |first1=Darja Obradovic |last2=Aspenberg |first2=Per |date=2011-08-01 |title=Where did bone come from? |url=|journal=Acta Orthopaedica |volume=82 |issue=4 |pages=393–398 |doi=10.3109/17453674.2011.588861 |issn=1745-3674 |pmc=3237026 |pmid=21657973}}

A macroevolutionary benchmark study is Sepkoski's{{Cite journal|last=Sepkoski|first=J. John|date=1981|title=A factor analytic description of the Phanerozoic marine fossil record|journal=Paleobiology|volume=7|issue=1|pages=36–53|doi=10.1017/s0094837300003778|bibcode=1981Pbio....7...36S |issn=0094-8373}}{{Cite journal|last=Sepkoski|first=J. John|date=1984|title=A kinetic model of Phanerozoic taxonomic diversity. III. Post-Paleozoic families and mass extinctions|journal=Paleobiology|volume=10|issue=2|pages=246–267|doi=10.1017/s0094837300008186|bibcode=1984Pbio...10..246S |issn=0094-8373}} work on marine animal diversity through the Phanerozoic. His iconic diagram of the numbers of marine families from the Cambrian to the Recent illustrates the successive expansion and dwindling of three "evolutionary faunas" that were characterized by differences in origination rates and carrying capacities. Long-term ecological changes and major geological events are postulated to have played crucial roles in shaping these evolutionary faunas.{{cite journal |last1=Rojas |first1=A. |last2=Calatayud |first2=J. |last3=Kowalewski |first3=M. |last4=Neuman |first4=M. |last5=Rosvall |first5=M. |title=A multiscale view of the Phanerozoic fossil record reveals the three major biotic transitions. |journal=Communications Biology |date=March 8, 2021 |volume=4 |issue=1 |page=309 |doi=10.1038/s42003-021-01805-y |pmid=33686149 |issn=2399-3642|pmc=7977041 }}

Macroevolution is driven by differences between species in origination and extinction rates. Remarkably, these two factors are generally positively correlated: taxa that have typically high diversification rates also have high extinction rates. This observation has been described first by Steven Stanley, who attributed it to a variety of ecological factors.{{Cite book|last=Stanley, Steven M.|title=Macroevolution, pattern and process|date=1979|publisher=W.H. Freeman|isbn=0-7167-1092-7|location=San Francisco|oclc=5101557}} Yet, a positive correlation of origination and extinction rates is also a prediction of the Red Queen hypothesis, which postulates that evolutionary progress (increase in fitness) of any given species causes a decrease in fitness of other species, ultimately driving to extinction those species that do not adapt rapidly enough.{{Cite journal|last=Van Valen|first=L.|date=1973|title=A new evolutionary law|journal=Evolutionary Theory|volume=1|pages=1–30}} High rates of origination must therefore correlate with high rates of extinction. Stanley's rule, which applies to almost all taxa and geologic ages, is therefore an indication for a dominant role of biotic interactions in macroevolution.

{{Multiple image

| image1 = 202208 Fruit fly female adult from a overhead view.svg

| image2 = 202208 Fruit fly bithorax complex.svg

| footer = Mutations in the Ultrabithorax gene lead to a duplication of wings in fruit flies.

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| caption1 = Normal phenotype

| caption2 = Bithorax phenotype

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While the vast majority of mutations are inconsequential, some can have a dramatic effect on morphology or other features of an organism. One of the best studied cases of a single mutation that leads to massive structural change is the Ultrabithorax mutation in fruit flies. The mutation duplicates the wings of a fly to make it look like a dragonfly, a different order of insect.

{{Main|Multicellular organism}}

The evolution of multicellular organisms is one of the major breakthroughs in evolution. The first step of converting a unicellular organism into a metazoan (a multicellular organism) is to allow cells to attach to each other. This can be achieved by one or a few mutations. In fact, many bacteria form multicellular assemblies, e.g. cyanobacteria or myxobacteria. Another species of bacteria, Jeongeupia sacculi, form well-ordered sheets of cells, which ultimately develop into a bulbous structure.{{Cite journal |last1=Datta |first1=Sayantan |last2=Ratcliff |first2=William C |date=2022-10-11 |title=Illuminating a new path to multicellularity |journal=eLife |volume=11 |pages=e83296 |doi=10.7554/eLife.83296 |pmid=36217823 |issn=2050-084X |pmc=9553208 |doi-access=free }}{{Cite journal |last1=Mizuno |first1=Kouhei |last2=Maree |first2=Mais |last3=Nagamura |first3=Toshihiko |last4=Koga |first4=Akihiro |last5=Hirayama |first5=Satoru |last6=Furukawa |first6=Soichi |last7=Tanaka |first7=Kenji |last8=Morikawa |first8=Kazuya |date=2022-10-11 |editor-last=Goldstein |editor-first=Raymond E |editor2-last=Weigel |editor2-first=Detlef |title=Novel multicellular prokaryote discovered next to an underground stream |journal=eLife |volume=11 |pages=e71920 |doi=10.7554/eLife.71920 |pmid=36217817 |pmc=9555858 |issn=2050-084X |doi-access=free }} Similarly, unicellular yeast cells can become multicellular by a single mutation in the ACE2 gene, which causes the cells to form a branched multicellular form.{{Cite journal |last1=Ratcliff |first1=William C. |last2=Fankhauser |first2=Johnathon D. |last3=Rogers |first3=David W. |last4=Greig |first4=Duncan |last5=Travisano |first5=Michael |date=May 2015 |title=Origins of multicellular evolvability in snowflake yeast |journal=Nature Communications |language=en |volume=6 |issue=1 |pages=6102 |doi=10.1038/ncomms7102 |issn=2041-1723 |pmc=4309424 |pmid=25600558|bibcode=2015NatCo...6.6102R }}

The wings of bats have the same structural elements (bones) as any other five-fingered mammal (see periodicity in limb development). However, the finger bones in bats are dramatically elongated, so the question is how these bones became so long. It has been shown that certain growth factors such as bone morphogenetic proteins (specifically Bmp2) is over expressed so that it stimulates an elongation of certain bones. Genetic changes in the bat genome identified the changes that lead to this phenotype and it has been recapitulated in mice: when specific bat DNA is inserted in the mouse genome, recapitulating these mutations, the bones of mice grow longer.{{Cite journal |last1=Sears |first1=Karen E. |last2=Behringer |first2=Richard R. |last3=Rasweiler |first3=John J. |last4=Niswander |first4=Lee A. |date=2006-04-25 |title=Development of bat flight: Morphologic and molecular evolution of bat wing digits |journal=Proceedings of the National Academy of Sciences |language=en |volume=103 |issue=17 |pages=6581–6586 |doi=10.1073/pnas.0509716103 |issn=0027-8424 |pmc=1458926 |pmid=16618938|bibcode=2006PNAS..103.6581S |doi-access=free }}

{{main|Limbless vertebrates}}

File:Vine-thicket Fine-lined Slider (Lerista cinerea).jpg which shows many intermediary steps with increasing loss of digits and toes. The species shown here, Lerista cinerea, has no digits and only 1 toe left.]]

Snakes evolved from lizards. Phylogenetic analysis shows that snakes are actually nested within the phylogenetic tree of lizards, demonstrating that they have a common ancestor.{{Cite journal |last1=Streicher |first1=Jeffrey W. |last2=Wiens |first2=John J. |date=2017-09-30 |title=Phylogenomic analyses of more than 4000 nuclear loci resolve the origin of snakes among lizard families |journal=Biology Letters |volume=13 |issue=9 |pages=20170393 |doi=10.1098/rsbl.2017.0393 |pmc=5627172 |pmid=28904179}} This split happened about 180 million years ago and several intermediary fossils are known to document the origin. In fact, limbs have been lost in numerous clades of reptiles, and there are cases of recent limb loss. For instance, the skink genus Lerista has lost limbs in multiple cases, with all possible intermediary steps, that is, there are species which have fully developed limbs, shorter limbs with 5, 4, 3, 2, 1 or no toes at all.{{Cite journal |last1=Skinner |first1=Adam |last2=Lee |first2=Michael SY |last3=Hutchinson |first3=Mark N |date=2008 |title=Rapid and repeated limb loss in a clade of scincid lizards |journal=BMC Evolutionary Biology |language=en |volume=8 |issue=1 |pages=310 |doi=10.1186/1471-2148-8-310 |issn=1471-2148 |pmc=2596130 |pmid=19014443 |doi-access=free |bibcode=2008BMCEE...8..310S }}

While human evolution from their primate ancestors did not require massive morphological changes, our brain has sufficiently changed to allow human consciousness and intelligence. While the latter involves relatively minor morphological changes it did result in dramatic changes to brain function.{{Cite book |url=https://www.worldcat.org/oclc/903489046 |title=Macroevolution: explanation, interpretation and evidence |date=2015 |first1=Emanuele |last1=Serrelli |first2=Nathalie |last2=Gontier |isbn=978-3-319-15045-1 |location=Cham |oclc=903489046}} Thus, macroevolution does not have to be morphological, it can also be functional.

The study of human (brain) evolution benefits from the fact that human and ape genomes are available so that the genomes of our common ancestor can be reconstructed.{{Cite journal |last=Hara |first=Yuichiro |last2=Imanishi |first2=Tadashi |last3=Satta |first3=Yoko |date=2012 |title=Reconstructing the demographic history of the human lineage using whole-genome sequences from human and three great apes |url=https://pubmed.ncbi.nlm.nih.gov/22975719 |journal=Genome Biology and Evolution |volume=4 |issue=11 |pages=1133–1145 |doi=10.1093/gbe/evs075 |issn=1759-6653 |pmc=3752010 |pmid=22975719}} Even though the precise genetic mechanisms that shaped the human brain are not known, the mutations involved in human brain evolution are largely known, given that the genes expressed in the brain are relatively well understood.{{Cite journal |last=Naumova |first=Oksana Yu |last2=Lee |first2=Maria |last3=Rychkov |first3=Sergei Yu |last4=Vlasova |first4=Natalia V. |last5=Grigorenko |first5=Elena L. |date=2013 |title=Gene expression in the human brain: the current state of the study of specificity and spatiotemporal dynamics |url=https://pubmed.ncbi.nlm.nih.gov/23145569 |journal=Child Development |volume=84 |issue=1 |pages=76–88 |doi=10.1111/cdev.12014 |issn=1467-8624 |pmc=3557706 |pmid=23145569}}

File:Zootoca vivipara. 3epo.Post.jpg) consists of populations that are egg-laying or live-bearing, demonstrating that this dramatic difference can even evolve within a species.]]

Most lizards are egg-laying and thus need an environment that is warm enough to incubate their eggs. However, some species have evolved viviparity, that is, they give birth to live young, as almost all mammals do. In several clades of lizards, egg-laying (oviparous) species have evolved into live-bearing ones, apparently with very little genetic change. For instance, a European common lizard, Zootoca vivipara, is viviparous throughout most of its range, but oviparous in the extreme southwest portion.{{Cite journal |last=Heulin |first=Benoît |date=1990-05-01 |title=Étude comparative de la membrane coquillère chez les souches ovipare et vivipare du lézard Lacerta vivipara |url=http://www.nrcresearchpress.com/doi/10.1139/z90-147 |journal=Canadian Journal of Zoology |language=en |volume=68 |issue=5 |pages=1015–1019 |doi=10.1139/z90-147 |bibcode=1990CaJZ...68.1015H |issn=0008-4301|url-access=subscription }}{{Cite journal |last1=Arrayago |first1=Maria-Jesus |last2=Bea |first2=Antonio |last3=Heulin |first3=Benoit |date=1996 |title=Hybridization Experiment between Oviparous and Viviparous Strains of Lacerta vivipara: A New Insight into the Evolution of Viviparity in Reptiles |url=https://www.jstor.org/stable/3892653 |journal=Herpetologica |volume=52 |issue=3 |pages=333–342 |jstor=3892653 |issn=0018-0831}} That is, within a single species, a radical change in reproductive behavior has happened. Similar cases are known from South American lizards of the genus Liolaemus which have egg-laying species at lower altitudes, but closely related viviparous species at higher altitudes, suggesting that the switch from oviparous to viviparous reproduction does not require many genetic changes.{{Cite journal |last1=Ii |first1=James A. Schulte |last2=Macey |first2=J. Robert |last3=Espinoza |first3=Robert E. |last4=Larson |first4=Allan |date=January 2000 |title=Phylogenetic relationships in the iguanid lizard genus Liolaemus: multiple origins of viviparous reproduction and evidence for recurring Andean vicariance and dispersal |journal=Biological Journal of the Linnean Society |language=en |volume=69 |issue=1 |pages=75–102 |doi=10.1111/j.1095-8312.2000.tb01670.x|doi-access=free }}

Most animals are either active at night or during the day. However, some species switched their activity pattern from day to night or vice versa. For instance, the African striped mouse (Rhabdomys pumilio), transitioned from the ancestrally nocturnal behavior of its close relatives to a diurnal one. Genome sequencing and transcriptomics revealed that this transition was achieved by modifying genes in the rod phototransduction pathway, among others.{{Cite journal |last1=Richardson |first1=Rose |last2=Feigin |first2=Charles Y. |last3=Bano-Otalora |first3=Beatriz |last4=Johnson |first4=Matthew R. |last5=Allen |first5=Annette E. |last6=Park |first6=Jongbeom |last7=McDowell |first7=Richard J. |last8=Mereby |first8=Sarah A. |last9=Lin |first9=I-Hsuan |last10=Lucas |first10=Robert J. |last11=Mallarino |first11=Ricardo |date=August 2023 |title=The genomic basis of temporal niche evolution in a diurnal rodent |url=|journal=Current Biology |volume=33 |issue=15 |pages=3289–3298.e6 |doi=10.1016/j.cub.2023.06.068 |pmid=37480852 |pmc=10529858 |bibcode=2023CBio...33E3289R |issn=0960-9822 }}

Subjects studied within macroevolution include:Grinin, L., Markov, A. V., Korotayev, A. Aromorphoses in Biological and Social Evolution: Some General Rules for Biological and Social Forms of Macroevolution / Social evolution & History, vol.8, num. 2, 2009 [http://www.socionauki.ru/journal/articles/129272/]

• Adaptive radiations such as the Cambrian Explosion.
• Changes in biodiversity through time.
• Evo-devo (the connection between evolution and developmental biology)
• Genome evolution, like horizontal gene transfer, genome fusions in endosymbioses, and adaptive changes in genome size.
• Mass extinctions.
• Estimating diversification rates, including rates of speciation and extinction.
• The debate between punctuated equilibrium and gradualism.
• The role of development in shaping evolution, particularly such topics as heterochrony and phenotypic plasticity.

• Extinction event
• Interspecific competition
• Microevolution
• Molecular evolution
• Punctuated equilibrium
• Red Queen hypothesis
• Speciation
• Transitional fossil
• Unit of selection

{{notelist}}

{{Reflist}}

• What is marcroevolution? (pdf) https://onlinelibrary.wiley.com/doi/full/10.1111/pala.12465
• {{cite web|last=AAAS |first=American Association for the Advancement of Science |author-link=American Association for the Advancement of Science |date=16 February 2006 |title=Statement on the Teaching of Evolution |publisher=aaas.org |url=http://www.aaas.org/news/releases/2006/pdf/0219boardstatement.pdf |access-date=2007-01-14 |url-status=dead |archive-url=https://web.archive.org/web/20060221125539/http://www.aaas.org/news/releases/2006/pdf/0219boardstatement.pdf |archive-date=21 February 2006}}
• {{cite book|last=IAP |first=Interacademy Panel |date=2006-06-21 |title=IAP Statement on the Teaching of Evolution |publisher=interacademies.net |url=http://www.interacademies.net/Object.File/Master/6/150/Evolution%20statement.pdf |access-date=2007-01-14 |url-status=dead |archive-url=https://web.archive.org/web/20060705140010/http://www.interacademies.net/Object.File/Master/6/150/Evolution%20statement.pdf |archive-date=5 July 2006}}
• {{cite journal |last=Myers |first=P.Z. |author-link=PZ Myers |date=2006-06-18 |title=Ann Coulter: No Evidence for Evolution? |journal=Pharyngula |publisher=ScienceBlogs |url=http://scienceblogs.com/pharyngula/2006/06/ann_coulter_no_evidence_for_ev.php |access-date=2007-09-12 |url-status=dead |archive-url=https://web.archive.org/web/20060622031856/http://scienceblogs.com/pharyngula/2006/06/ann_coulter_no_evidence_for_ev.php |archive-date=22 June 2006 }}
• {{Cite web |last=NSTA |first=National Science Teachers Association |author-link=National Science Teachers Association |year=2007 |title=An NSTA Evolution Q&A |url=http://www.nsta.org/publications/evolution.aspx |access-date=2008-02-01 |url-status=dead |archive-url=https://web.archive.org/web/20080202043206/http://www.nsta.org/publications/evolution.aspx |archive-date=2 February 2008 }}
• {{cite web |last=Pinholster |first=Ginger |date=19 February 2006 |title=AAAS Denounces Anti-Evolution Laws as Hundreds of K-12 Teachers Convene for 'Front Line' Event |publisher=aaas.org |url=http://www.aaas.org/news/releases/2006/0219boardstatement.shtml |access-date=2007-01-14 |archive-date=19 October 2013 |archive-url=https://web.archive.org/web/20131019171834/http://www.aaas.org/news/releases/2006/0219boardstatement.shtml |url-status=dead }}

• [http://evolution.berkeley.edu/evolibrary/article/0_0_0/evo_47 Introduction to macroevolution]
• [http://www.talkorigins.org/faqs/comdesc/ Macroevolution as the common descent of all life]
• [http://www.nhm.ac.uk/hosted_sites/paleonet/paleo21/mevolution.html Macroevolution in the 21st century] Macroevolution as an independent discipline.
• [http://www.talkorigins.org/faqs/macroevolution.html Macroevolution FAQ]

{{evolution}}

Category:Evolutionary biology