New orang species Rainforest Action Network
Apparently
Apparently
New Orangutan Species Discovered
- Thread starter Ned
- Start date
Here is the scientific paper from Current Biology about the Tapanuli orangutan Pongo tapanuliensis.
http://www.cell.com/current-biology/fulltext/S0960-9822(17)31245-9
http://www.cell.com/current-biology/fulltext/S0960-9822(17)31245-9
another report here
New great ape discovered... and immediately listed as world's most endangered
New great ape discovered... and immediately listed as world's most endangered
Interestingly they are in a way more closely related to Bornean orang utan, though there has been irregular but constant gene flow from some males of the "real" Sumatran orang utans up to about 10-20 thousand years ago.
This seems thoroughly unlikely on the face of it. I couldn't open the link from @DesertRhino150 but I found the following article which explains the scenario of it being distinct in simple terms, and in that article there is a link to the scientific paper which did open for me (so if you can't open the earlier link try the one in my article below). It is definitely interesting and seems solid enough.
New Species of Orangutan Is Rarest Great Ape on Earth
New Species of Orangutan Is Rarest Great Ape on Earth
Hmm... I’d be curious to know if any captive orangutans thought to be P. abelii are in fact P. tapanuliensis. Perhaps a genomic analysis is necessary?
I'll be interested in how this plays out - whether it sticks or if it gets refuted with more study. I've seen the Bornean and Sumatran Orangutans, so I guess I'm going to have to try and go see this one as well if it actually is a distinct species.
The problem with all the splitting is that my percentage of "wild-seen" Asian primates keeps creeping downwards. I was on 50% of all species and now I'm on about 45%
The problem with all the splitting is that my percentage of "wild-seen" Asian primates keeps creeping downwards. I was on 50% of all species and now I'm on about 45%
Second it would be interesting to check if there are these animals in captivity in Indonesia or elsewhere. Yet another animal which will never be safe in the wild, due to already very small range.
It would be also interesting to check if some isolated populations of chimps and gorillas do the same tricks with genetics.
About 'species' status - I see it only as an evidence of taxonomic over-splitting used as a handy tool to raise publicity. The paper itself points that 'sumatran', 'bornean' and 'tapas' orangutans hybridized naturally.
It would be also interesting to check if some isolated populations of chimps and gorillas do the same tricks with genetics.
About 'species' status - I see it only as an evidence of taxonomic over-splitting used as a handy tool to raise publicity. The paper itself points that 'sumatran', 'bornean' and 'tapas' orangutans hybridized naturally.
But it was also pointing out that other well-supported species likewise show evidence of hybridisation.
I'm not sure I'd call it taxonomic over-splitting, although I don't deny that people often do that and one could make the argument for it here. The idea of a "species" is just a constructed category that we use for our own purposes; in reality, it's more of a spectrum, where a species is more or less related to one species than to another. Coyotes and wolves interbreed regularly in areas where they cohabit, but they are generally agreed to be two separate species.
I also thought this might merely be more scientific 'over-splitting' as opposed to 'lumping'. I still find it difficult to regard Orangutan as two seperate species, rather than subspecies. The differences between them are clearcut but are they really sufficient to reclassify them at species level? And they will hybridise freely also and afaik those hybrids will be fertile also.
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If I read it right the suggestion is that after (or at the same time as) isolation from other Sumatran populations occurred, there was still geneflow from the Bornean orangutans? The accompanying photos do show animals that (superficially anyway) still look typically Sumatran in appearance to me, though I would need to see much more close-up detail before I could pick out any more distinguishing characteristics.
I tend to agree with your first statement-that first and foremost it engenders publicity.
It's an almost certainty that orangutans in Asian zoos are a mix of the two forms. The distance between the areas they occupy is small. I would suggest that it is highly likely rescue animals would already be amongst those released at the rehabilitation centres in northern Sumatra (within abelii range). It's also pretty likely that both forms are, to some degree, within foreign zoos' Sumatran orangutan populations.
This link has photos of all three, plus an easy chart-map to show the time-frame of the divergences. It's pretty easy to find photos of Tapanuli orangutans on the internet too (Tapanuli is a district quite separate from the more northerly populations, and the orangutans are a montane population, so have been studied quite a lot).
Pongo Tapanuliensis - www.batangtoru.org
Of the gene-flow between populations:
"Under our best-fitting model, we found evidence for post-split gene flow across Lake Toba (∼0.3–0.9 migrants per generation; Table S5), which is consistent with highly significant signatures of gene flow between P. abelii and P. tapanuliensis using D statistics"
"The existence of two deep evolutionary lineages among extant Sumatran orangutans was corroborated by phylogenetic analyses based on whole mitochondrial genomes (Figure 4A), in which the deepest split occurred between populations north of Lake Toba and all other orangutans at ∼3.97 Ma (95% HPD: 2.35–5.57). Sumatran orangutans formed a paraphyletic group, with P. tapanuliensis being more closely related to the Bornean lineage from which it diverged ∼2.41 Ma (1.26–3.42 Ma). In contrast, Bornean populations formed a monophyletic group with a very recent mitochondrial coalescence at ∼160 ka (94–227 ka)."
"The single available Y-haplotype from P. tapanuliensis was nested within the other Sumatran sequences, pointing at the occurrence of male-mediated gene flow across the Toba divide."
"Our analyses revealed significant divergence between P. tapanuliensis and P. abelii (Figures 3B and 4A) and low levels of male-mediated gene flow (Figures 3 B and 4B), which, however, completely ceased 10–20 kya (Figure 3C). Populations north and south of Lake Toba on Sumatra had been in genetic contact for most of the time since their split, but there was a marked reduction in gene flow after ∼100 ka (Figure 3C), consistent with habitat destruction caused by the Toba supereruption 73 kya [35]. However, P. tapanuliensis and P. abelii have been on independent evolutionary trajectories at least since the late Pleistocene/early Holocene, as gene flow between these populations has ceased completely 10–20 kya (Figure 3C) and is now impossible because of habitat loss in areas between the species’ ranges"
Most gibbons also hybridise freely and produce fertile offspring.
Thanks for the above links Chlidonias. It seems the 'tapanuli' Orangs are the ancestors of the Bornean orangs, not the other way around as I first thought. The photos and morphological differences are interesting too. They do still look essentially Sumatran to me, so maybe what happened is that Borneans evolved their own different morphological characteristics after isolation on Borneo. Fascinating stuff. I think they need a simpler name for the new 'species' though.
Here's an article arguing against the claim of the orangutan being a distinct species. It isn't very well written (there are two authors giving their viewpoints, and neither is convincing to me). Their basic argument seems to be that there is evidence of interbreeding and therefore all orangutans are a single species.
Some of their points are clearly debatable - e.g. the second author states as fact that there is only one species of gorilla (most primatologists now accept there being two species) and both state that neanderthals and humans are conspecific (a position heavily overshadowed by the position that they were separate species). This shows pretty obviously that they were never going to accept the Tapanuli Orangutan in the first place.
There's a very specific viewpoint repeated constantly in there too (and in the comments) that taxa which produce fertile offspring when interbreeding must be single species, which obviously calls into question where they would stand on canids, ducks, macaws, and any of those other groups which hybridise freely and produce fertile offspring.
Also, I just have to repeat a bit from the comments (by the main author) where he says "That, in fact, is exactly what zoos are doing making “cocktail orangs” by breeding Sumatran and Bornean orangs. They’re trying to keep the genetic diversity of both populations in captivity."
A new species of orangutan? I doubt it.
Some of their points are clearly debatable - e.g. the second author states as fact that there is only one species of gorilla (most primatologists now accept there being two species) and both state that neanderthals and humans are conspecific (a position heavily overshadowed by the position that they were separate species). This shows pretty obviously that they were never going to accept the Tapanuli Orangutan in the first place.
There's a very specific viewpoint repeated constantly in there too (and in the comments) that taxa which produce fertile offspring when interbreeding must be single species, which obviously calls into question where they would stand on canids, ducks, macaws, and any of those other groups which hybridise freely and produce fertile offspring.
Also, I just have to repeat a bit from the comments (by the main author) where he says "That, in fact, is exactly what zoos are doing making “cocktail orangs” by breeding Sumatran and Bornean orangs. They’re trying to keep the genetic diversity of both populations in captivity."
A new species of orangutan? I doubt it.
It seems that there are still a lot of biologists who accept the idea of the Biological Species Concept as the one and only way to define a species, even though most taxonomists and basically all recent publications don't acknowledge it anymore. I am not sure what to think of the new orang species, where calling it a species has given them a LOT of publicity for sure. The problem is that it is a bit of a hybrid between Borneans and Sumatrans. It for sure show once again the complexity of evolution and how it gives rise to different taxa....
That must be the most uninformed statement of the day
Same here. My initial thought was that having two orangutan species on Sumatra was ridiculous, but the paper and the explanations within it seems good to me. I'm not wholly convinced it's a distinct species, but at the moment I'm happy to accept it.