Talk:Algae

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"The break-even point for algae-based biofuels is estimated to occur by 2025." 85.247.220.142 (talk) 09:12, 5 September 2024 (UTC)

I hate to be saying this, but since when are cyanobacteria not considered algae? Literally every text-book I've ever seen refers to algae as containing cyanobacteria, as well. — Snoteleks (talk) 19:05, 11 May 2025 (UTC)

:From {{alink|Classification}}? {{tbq|Although cyanobacteria are often referred to as "blue-green algae", most authorities exclude all prokaryotes, including cyanobacteria, from the definition of algae.}} Remsense ‥ 论 19:12, 11 May 2025 (UTC)

::You're telling me one dictionary entry from 1992 and one botany book from 2004 alone support this absurd claim throughout the entire article? This level-3 vital article can certainly do better. Here, a list of authorities that count cyanobacteria as algae, and differentiate eukaryotic algae from algae in general:

::* {{cite book|title=Algae: Anatomy, Biochemistry, and Biotechnology|edition=2nd|publisher=CRC Press|date=2014|vauthors=Barsanti L, Gualtieri P|isbn=978-1-4398-6733-4}}

::* {{cite book|title=Freshwater Algae: Identification, Enumeration and Use as Bioindicators|publisher=Wiley Blackwell|vauthors=Bellinger EG, Sigee DC|edition=2nd|date=2015|isbn=978-1-118-91716-9}} {{tq|The colour of freshwater algae is an important aspect of their classification, and ranges from blue-green (Cyanobacteria) to grass green (Chlorophyta), golden brown (Chrysophyta, Bacillariophyta), brown (Phaeophyta) and red (Rhodophyta).}}

::* {{cite book|title=Unravelling the algae: the past, present, and future of algal systematics|veditors=Brodie J, Lewis J|series=The Systematics Association Special Volume Series|volume=75|date=2007|publisher=CRC Press|isbn=978-0-8493-7989-5}} {{tq|The prokaryotic cyanobacteria have frequently been included with the algae. Indeed in this volume, we have included the cyanobacteria because they are so much a part of the “algal world” and they provide such fascinating insights into the genetics of organisms.}}

::* {{cite book|veditors=Bux F, Chisti Y|title=Algae Biotechnology: Products and Processes|publisher=Springer|date=2016|doi=10.1007/978-3-319-12334-9|isbn=978-3-319-12333-2}}

::* {{cite book|title=Algae|edition=3rd|veditors=Graham LE, Graham JM, Wilcox LW, Cook ME|publisher=LJLM Press|date=2016|isbn=978-0-9863935-3-2}}

::* {{cite book|title=Algae|edition=4th|veditors=Graham LE, Graham JM, Wilcox LW, Cook ME|publisher=LJLM Press|date=2022|isbn=978-0-9863935-4-9}} Literal fist sentence of the first section of the first chapter: {{tq|The algae are a heterogeneous assemblage of organisms that range in size from tiny single cells to giant seaweeds and that belong to diverse evolutionary lineages. As a result, the algae are largely defined by ecological traits. The algae are mostly photosynthetic species that produce oxygen and live in aquatic habitats. In addition, the algae lack the body and reproductive features of the land plants that represent adaptations to terrestrial life. This concept of the algae includes both photosynthetic protists, which are eukaryotes, and the prokaryotic oxygenic cyanobacteria, also known as blue-green algae.}}

::* {{cite book|title=Phycology|edition=5th|vauthors=Lee RE|publisher=Cambridge University Press|doi=10.1017/9781316407219|date=2018|isbn=978-1-107-55565-5}} The second chapter reads: {{tq|Part II. The Prokaryotic Algae. The cyanobacteria or blue-green algae form a natural group by virtue of being the only prokaryotic algae.}}

::* {{cite book|title=River Algae|veditors=Necchi O|isbn=978-3-319-31984-1|doi=10.1007/978-3-319-31984-1_2|publisher=Springer|date=2016|chapter=Chapter 2. Blue-Green Algae (Cyanobacteria) in Rivers|vauthors=Casamatta DA, Hašler P|pages=5-34}}

::* {{cite book|chapter=Classification of Algae|vauthors=Baweja P, Sahoo D|pages=31-55|doi=10.1007/978-94-017-7321-8_2|title=The Algae World|veditors=Sahoo D, Seckbach J|series=Cellular Origin, Life in Extreme Habitats and Astrobiology|volume=26|publisher=Springer|isbn=978-94-017-7321-8}}

::* {{Cite book|chapter=Protist Diversity and Eukaryote Phylogeny|title=Handbook of the Protists|date=2017|isbn=978-3-319-28147-6|editor-last1=Archibald|editor-first1=John M.|editor-last2=Simpson|editor-first2=Alastair G.B.|editor-last3=Slamovits|editor-first3=Claudio H.|edition=2nd|publisher=Springer|pages=1–22|last1=Simpson|first1=Alastair G. B.|last2=Slamovits|first2=Claudio H.|last3=Archibald|first3=John M.|volume=1|doi=10.1007/978-3-319-28149-0_45}} {{tq|Most major lineages of photosynthetic eukaryotes actually have plastids that were obtained by symbiosis with eukaryotic algae, rather than by symbiosis with cyanobacteria.}}

::* {{cite book|publisher=Faculty of Sciences, University of A Coruña|date=2009|vauthors=Bárbara I|title=Algas bentónicas marinas y salobres de Galicia: iconografías y claves de identificación|trans-title=Marine and brackish benthic algae of Galicia: iconographies and identification keys|language=Spanish}}

::Almost all of these sources are widely used among phycologists (some may even be cited in this article). So, please, let us stop pretending that this random interpretation of the term algae is not biased or, at the very least, inaccurate. — Snoteleks (talk) 22:54, 11 May 2025 (UTC)

:::Just noting I'm the least biologist of those present by orders of magnitude, so I just dumbly transferred the article section I thought seemed cogent. Remsense ‥ 论 22:55, 11 May 2025 (UTC)

::::Completely understandable. I'm just very passionate about this and wanted to take the chance to fill in with bibliography. — Snoteleks (talk) 22:59, 11 May 2025 (UTC)

:If we use the colloquial term "algae," yes, cyanobacteria are algae because they are photosynthetic organisms that are neither plants, nor photosynthetic animals. If we use the taxonomic term "algae," then no, cyanobacteria are not algae because they are not photosynthetic eukaryotes excluding Embryophyta. Mr Fink (talk) 20:11, 11 May 2025 (UTC)

::@Apokryltaros There is no such taxonomic term. Algae are not a taxon. You are perhaps thinking of green algae. — Snoteleks (talk) 20:41, 11 May 2025 (UTC)

:I brought the same issue up a few months ago on the [https://en.wikipedia.org/wiki/Wikipedia_talk:WikiProject_Algae WP:Algae Talk Page] when I was very new to WP editing. I'm on mobile so it's clunky to look back, but IIRC, someone changed it to be much more inclusive of cyanos but note that there are some dissenting opinions.

:I fully agree and I would be surprised in any scientific setting to hear someone say cyanobacteria aren't algae (but wouldn't discredit them immediately, I suppose.) Saying "most scientists exclude cyanobacteria" is absolutely inaccurate and should be changed wherever. Given that algae already is never going to be a valid taxonomic group, excluding cyanobacteria seems odd.

:Beyond my scientific perspective, many cyanobacteria are the cause of harmful algal blooms and are reported as such. I think it would be detrimental to have such conflicting information to anyone wanting to learn more. Though maybe it's worth a footnote of some kind that some people do not agree about cyanobacteria inclusion in algae.

:(Anecdotally though not a source/evidence for this, I had to define algae in my comprehensive oral exams for my PhD and I did need to include cyanobacteria in that...) Cyanochic (talk) 03:58, 12 May 2025 (UTC)

:: The earlier discussion is at Wikipedia_talk:WikiProject_Algae#Using_the_terminology_%22algae%22_for_cyanobacteria

:: This is another example of a vernacular name used in different ways, where context matters. There is no question that cyanobacteria were originally considered algae, hence the name blue-green algae, and still are much of the time. However, if you look at various definitions, you see many saying photosynthetic eukaryotes, photosynthetic protists, or adding qualifications such as formerly including cyanobacteria.

:: The article has to reflect all uses, so it shouldn't define them as photosynthetic eukaryotes or protists to the exclusion of cyanobacteria, but it should mention that it is often/sometimes used more restrictively. I'll also note that it's not a scientific term so non-scientific sources should also be used. —  Jts1882 | talk  07:14, 12 May 2025 (UTC)

::: Incidentally, the eukaryotic was added to the opening sentence back in 2018 with [https://en.wikipedia.org/w/index.php?title=Algae&diff=prev&oldid=857222556 this edit], as was the most "most authorities exclude" statement. I suggest replacing eukaryotes with organisms in the opening sentence and adding a sentence along the lines of "Traditionally, the algae included cyanobacteria, although some authorities restrict the term to eukaryotes". Some is non-committal and is accurate even if it were most.  —  Jts1882 | talk  09:23, 12 May 2025 (UTC)

::::@Jts1882 Totally agree, it is accurate and non-committal. — Snoteleks (talk) 12:32, 12 May 2025 (UTC)

:::@Jts1882 I just don't see the reasoning for the notion that they "were" (in past tense) considered algae, by most accounts, in fact. The truth is, they are considered algae. Just like you said, it is not a scientific term, menaing that there is no such thing as a taxon of Algae that arbitrarily excludes cyanobacteria.

:::This article is very much not neutral about it. The first sentence in the lead immediately refers to them as a group of "photosynthetic eukaryotes" in the first sentence, and constantly showcases the cyanobacterial addition as some ancient artifact for no justified reason.

:::I'm not saying we should completely get rid of this notion, as indeed a few phycologists do exclude them. But this notion was unfairly overinflated by the aforementioned 2018 edits.

:::It's the same as if I went to the Plant article and removed all mentions of definitions that include other Archaeplastida except one, and wrote "historically, the term included the closely related glaucophytes, red algae, and green algae, but nowadays it is reserved exclusively for land plants". Even that, despite supporting the more popular opinion, would not be allowed by our encyclopedic standards, because it is simply a lie. — Snoteleks (talk) 12:29, 12 May 2025 (UTC)

::::Now that I'm on a computer, looking back at WP Algae Talk page, it looks like there are multiple returning people to this conversation. I think @Peter coxhead's initial response is certainly the most neutral and well supported way to address this issue, including citations to the ICNafp.

::::I think Cyanobacteria is also still misleading (last sentence of 1st paragraph "although as prokaryotes they are not scientifically classified as algae." I think talking about "scientific classification" of algae altogether should be removed given algae is not a "scientific classification" at all.

::::I've been in a wiki editing mood lately, I might start to compile an area on my user page for anything that has this issue given its come up multiple times and I know there's more out there. I will link that here if/when it's made. Cyanochic (talk) 14:41, 12 May 2025 (UTC)

::::I've created this user page to summarize and have as reference. While writing, I also noticed that the short description for "algae" also explicitly says "photosynthetic eukaryotes" and should be changed while edits are being made to improve the article text as well. Cyanochic (talk) 15:05, 12 May 2025 (UTC)

:::::See that's exactly what I mean. How someone seriously wrote "as prokaryotes they are not scientifically classified as algae" is beyond my comprehension. Thanks for your effort, if I see other places where this issue has come up I'll let you know in the talk of that page. — Snoteleks (talk) 16:47, 12 May 2025 (UTC)

::::::Alright I just took a stab at editing ONLY the first paragraph of this page to not be only eukaryotes, including a part of the same note from cyanobacteria, and altered the subheading to not read "photosynthetic eukaryotes". I also removed the final phrase of that sentence I referenced earlier from cyanobacteria. I did not look through the rest of the Algae article for other possible contradictions at this time however. Cyanochic (talk) 00:24, 13 May 2025 (UTC)

We should remember that algae are specifically capable of performing oxygenic photosynthesis, which excludes anoxygenic photosynthesis seen in purple bacteria and other prokaryotes. — Snoteleks (talk) 13:06, 19 May 2025 (UTC)

The article is difficult to read as the information is often displayed all over the place, and there is little cohesion. I'm going to try to reorganize it over the following days into something similar to this scheme:

1. Etymology and study
2. Description (intro would be the definition of algae, as in the "Classification" section)
3. Morphology
4. Nutrition (new)
5. Physiology (osmorregulation, etc.)
6. Life cycle
7. Diversity (new; merge of "Number" + "Classification" sections)
8. Cyanobacteria
9. Eukaryotic algae
10. Primary plastid algae
11. Secondary plastid algae
12. Evolution
13. Origin of oxygenic photosynthesis (new, essentially origin of cyanobacteria)
14. First endosymbiosis (new)
15. Serial endosymbioses (new)
16. Relationship to land plants
17. Plastid losses (new)
18. Ecology
19. Primary production
20. Biogeochemical cycles
21. Symbiotic algae
22. In human culture (new, as the present paragraph is completely uncited)
23. Cultivation
24. Use
25. Biofuel (=energy source)
26. Fertilizer
27. Food industry (actual food, pigments, stabilizers)
28. Gelling agents (agar, alginate)
29. Bioremediation and pollution control
30. Bioplastic (=polymers)

— Snoteleks (talk) 19:14, 20 May 2025 (UTC)

:I will also add a Distribution section which can house the awkward "local estimates" paragraphs from the current "Numbers" section. — Snoteleks (talk) 19:16, 20 May 2025 (UTC)

@User:Snoteleks Multiple and serial endosymbiosis are different terms. The more common term multiple endosymbiosis of a plastid is an endosymbiosis of an alga which has the plastid from the endosymbiosis of another alga. Serial endosymbiosis is specific and means that the ancestral plastid has been lost and replaced by another one in an act of endosymbiosis of another algae (the ochrophyte plastid was replaced in some dinoflagellates by other plastids, e.g. from cryptophytes, other ochrophytes, haptophytes, or green algae - the example is the green plastid in Lepidodinium).

So, be careful with the "serial endosymbiosis" application. Petr Karel (talk) 08:40, 21 May 2025 (UTC)

:@Petr Karel Oh! Thank you for bringing this to my attention, I wasn't aware. I will use the more accurate terminology. — Snoteleks (talk) 10:32, 21 May 2025 (UTC)

@User:Snoteleks Chlorarachniophyta are included in the AlgaeBase, but not as phylum. [https://www.algaebase.org/browse/taxonomy/#4326 Class Chlorarachniophyceae] (with 20 species) is included into phylum Cercozoa. In the same phylum the three [https://www.algaebase.org/browse/taxonomy/#104518 Paulinella] species are listed which perform the oxygenic photosynthesis (P. chromatophora, P. micropora and P. longichromatophora) with plastids with very specific origin, independent of all other chloroplasts. Are you sure, that all these algae were "omitted" (as written in the note)? Are their numbers not included in the last row with the strange name "Incertae sedis etc." (what etc. means?) Petr Karel (talk) 15:13, 22 May 2025 (UTC)

:@Petr Karel I haven't considered that possibility. I'll go check that. — Snoteleks (talk) 15:36, 22 May 2025 (UTC)

::@Petr Karel Hey, so I took a look and the situation is very weird. Within the 2024 paper there are a lot of inconsistencies between Table 1 with all the phyla and the individual phylum tables (e.g., Charophyta has 5644 total described species and 4940 living species in Table 1, but 5583 and 4879 in Table 3). The "Incertae sedis etc." row is never mentioned in the text, so there is no way to know what the author included as those.

::Judging by the number of species (2995), it could be that all protozoa listed in AlgaeBase are counted in this row, since a lot of Rhizaria appear in the database down to species level, not just Paulinella or chlorarachniophytes.

::It could also be that only truly incertae sedis taxa are listed here, as it is unknown whether they belong to one algal phylum or another, or even if they are really algae (e.g., the fossil [https://www.algaebase.org/search/species/detail/?species_id=192452 Chisibyllites kerguelensis], listed as Retaria incertae sedis). This would be consistent with Table 8 in the 2024 paper, where the 2995 species are listed as belonging to kingdom "Incertae" instead of any combination of the four other kingdoms.

::Another possibility is that Incertae sedis in that table only refers to fossil taxa, since the "living species" column is empty for this row; only the "species" column is filled with a number.

::It's honestly impossible to know for certain, and the numbers themselves are not as reliable as it seemed considering their variation between tables. Either we assume that "Incertae sedis etc." are just fossil taxa, or we assume that it's wrongly classifying protozoa as algae, and therefore we should probably find better references for each phylum instead. — Snoteleks (talk) 17:09, 22 May 2025 (UTC)

:::@Petr Karel Nevermind, the answer was in table 8 all along. It explicitly divides all species by kingdom into fossil and living, and the 2995 species listed as kingdom "Incertae" are all under the "Fossil" column. Chlorarachniophytes cannot be included here, because they are all living species. — Snoteleks (talk) 17:10, 22 May 2025 (UTC)

:::: Am I looking in the same place ([https://onlinelibrary.wiley.com/doi/10.1111/jpy.13431 here])? I see 2995 incertae species with 2475 fossil and no entry under living.  —  Jts1882 | talk  17:31, 22 May 2025 (UTC)

:::::@Jts1882 Oh huh, you're right, it says 2475 fossils and no living species, despite the total being larger. This is getting even stranger. I honestly don't know what to make of it, but I personally prefer to assume that chlorarachniophytes are not included until proven otherwise. — Snoteleks (talk) 22:06, 22 May 2025 (UTC)

:::::: If you check the counts in table 8 there are errors. The species total column underestimates the fossil+living count for the four kingdoms. The missing species number is the same as the extra 520 in the incertae sedis species total. It's as if some living species are assign to kingdoms for living column but are incertae sedis in the total species columm. The totals for the species total column and the summed fossil and living columns are the same (61145). Not sure this helps the main question.  —  Jts1882 | talk  14:05, 24 May 2025 (UTC)

:::::::Well, if anything, it helps knowing that the paper is not very reliable. I'm sure they're still a good approximation, but ideally we should use more accurate ones. I don't even know how Michael Guiry got those numbers in the first place; he runs AlgaeBase, so perhaps he has an algorithm that displays the number of entries automatically for him according to kingdom, phylum and order, but I don't know of any method to do the same as a user. — Snoteleks (talk) 01:12, 25 May 2025 (UTC)