I have been researching on the internet for a while now for a complete breakdown of all Gibbon species. I have come across two website in particular that seem to agree with each other to some degree. untitled About Gibbons These two agree that there are 4 genera (which most websites seem to agree with) with roughly around 15 species all together. Basically, after trying to find a list that the whole world (or at least the scientific world agrees too) is proving some what differcuilt. Any help on this matter would be great, or a realiable source where I can read the relevant information myself. Thanks in advance, Taun
I sympathise, but I'm afraid you won't get a definitive answer as even specialists disagree about matters like this. For what it's worth I'd go with the first site's version, which is based on chromosomal evidence rather than the second (which is a one man captive breeding operation, and seems to be entirely admirable, but is probably not as scientifically respectable). Alan
Thanks very much Gentle lemur, I was afraid that was going to be the answer Your right with the first site, seems much more realiable.
Hi taun, As far as "official" taxonomy goes, look at IUCN Red List. Gibbons, and all primates underwent a kind of taxonomic explosion in the last years, basically by changing definition of species into that every recognizable race became full species. The main reason seems to be PR or drawing more attention to "rare species" than "rare race". BTW, these gibbon "species" hybridise in the wild, including long-established "species" like Hylobates lar and Hylobates muelleri having a classical hybrid zone.
Thanks Jurek7, Interesting to learn that does this explain why orangutans have now be designated full species to draw more attention to the more endangered summartran? Yes Gibbons are similar to giraffe in the aspects hybrids because of overlapping range.
The most important recent sub--divisions in gibbon taxonomy have occurred in the Nomascus genus and the Hylobates (mainly confined to the H. agilis and H. muelleri complex). An offshoot is the recognition of Hoolock into 2 separate taxa and confined to the Indian subcontinent. Interestingly, if we base our divisions simply on taxonomy or morphology we may exclude the evidence from ecology. A very authoritive work on gibbon call systems has also been a recent introducee for distinghuishing between the various gibbon taxa who often even have sympatric and overlapping ranges! Will try to look up the work in case you are interested. Please note my deliberate abstention from entering into genetics, DNA or mitochondrials as I view that particular part of the evidence more tool than instrument in identifying the intricacies and complexes in gibbon taxonomy. All to often genetics research has been used to either lump or split where bio-geographical and taxonomical/morphological evidence put the perspective otherwise. Remember, it is a mere tool not a definitive definition in its own right. Only, by coupling the evidence from genetics research WITH morphological, taxonomical and ecological studies can we even begin to understand animal idenfication and separation into species or geni!
It's a bit more complex but yes that's part of the explanation. There's also an economic issue because it looks a lot better on the curriculum vitae to have described a new species than 'just' a subspecies. Also just people arguing over what species concept to use with some prefering the biological and others just prefering the phylogenetic. Biologists have been arguing over these things for centuries and that is unlikely to change anytime soon because the biological concept is a generally easier to use for ecologists but the phylogenetic concept is generally easier to use for geneticists and that's just two of the main concepts (there are many more less known). Primate taxonomy is a bit special because it is the only (I think?) branch of the mammals where all the main authorities (well, far from all, but the ones that publish most papers or books) prefer the phylogenetic over the biological.
To add to the previous comment: I clearly prefer the biological species concept but it can not be said as simply as morphology over genetics. In some uacaris that look very similar and were considered subspecies of a single species until recently it has been shown that their genetic distances are well beyond that known from close relatives that certainly are biological species as they overlap without interbreeding (yes I know there's an issue of calibration but that's not out of reach). There are some macaques that until recently were considered subspecies of the same species that now are known via genetics to not be each others closest relatives. Also some langurs that some argued were species a few years ago based on their morphology but genetics have shown that there is plenty of geneflow between them. In such cases it is clear (to me at least) that genetics must override morphology. Morphology can also easily be abused almost as easily as genetics. The arguments based on morphology used recently to split some of the crested mangabeys would likely result in more than one species of human if applied to us and morphological arguments that were presented a few years ago for splitting some lutungs are now known to be simply incorrect (even if some authorities still cling onto them as species). Both genetics and morphology have their place in biological species limits (even if strictly speaking hybridization is the only way but that's impossible for most species) but the weight of either has to be judged carefully from case to case. Even if disregarding the issue of species concepts it becomes very complex very fast!
