"Homo troglodytes" Genome Project, DNA 96% {us}

Mr. Jack,
I am forced to respectably disagree with you on what morphological characteristics quantify differences between species and/or genera (not genii, plural of genius not genus). As an invertebrate zoologist with a great interest in human evolution I have always been skeptical of the differences perceived between fossil and extant members of the Hominidae, Homininae in particular.I think it is very difficult to objectively look at differences in things that resemble ourselves. I think the study of human evolution has been clouded by this difficulty. In the pop-sci realm it has not better been illustrated than in the book Lucy The beginnings of humankind by Johanson and Edey. In their chapter 13 they discuss the analysis of what the fossils may be. The possibilities they explore are genus Homo, genus Australopithecus, or ‘something else’.The analysis concludes that the fossils (Lucy and the others representing Austrlopithecus afarensis) are australopithecines. Where I take exception is that the genus Pan was never considered (while they repeatedly made comparisons to this genus) as an alternate possibility.I wish I had better photos but I want to illustrate the difference between accepted congenerics in crustacean biology: and The first is less than 50 mm across the carapace the second is commonly 150 mm and above. Both are in the same genus and this is supported by abundant morphological data including larval development. I would argue that the difference between a dungeness crab and a dwarf cancer crab are orders of magnitude more than between a human and a chimpanzee. The numbers of invert congenerics that differ more than that would stagger the imagination.This message has been edited by Lithodid-Man, 09-03-2005 04:09 AMThis message has been edited by Lithodid-Man, 09-03-2005 04:25 AM

This may be an aside, but I wonder about the designation of Chimpanzees as Pan troglodytes versus Homo troglodytes. While that is better for our ego I wonder about ICZN rules about precendence. Pan was described as a genus in 1779 (I believe, by Blumenbach). If Robert Bakker is correct in his analysis of Linnaeus' work then the genus Homo was not described formally until 1993. All of the 20th century fossil discoveries claiming Homo as the genus might be suspect. As I understand the ICZN rules then we would become Pan sapiens rather than chimps becomming Homo troglodytes. Holy ego blow Batman!

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"Invert congenerics" - I don't know the term, please explain?

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I apologize for being unclear. I was referring to invertebrates that are placed in the same genus but differ significantly more than do humans and chimps. In a very real sense the variation within tetrapods even is small when compared to some invertebrate taxa we are comfortable lumping together.As for congenerics I wanted to illustrate using the polychaete genus Prionospio but couldn't find good photos online to link to. Within this genus there are variations in the number of gills. Because they are worms one with two pairs of gills looks pretty much like one with four or seven pairs to us. But what is missed is that developmentally this would be like vertebrates varying by having six limbs or extra pharyngeal pouches within a single genus.