Humans and apes

[John Grehan]

>>Jason de Koning wrote:
>>In addition, there is plenty of morphological data that gives strong support
>>to a basal position for Orangutan.  For instance, cladistic analysis of 264
>>cranial/post-cranial morphological characters in Shoshani et al., showed
>>strong support for (O(G(HC)).  (Mol Phyl Evol 1996, 5:102-154)  This is not
>>a molecules versus morphology question.

Agnes Dettai wrote

>I agree with Jason. The man-chimp clade is not supported only by sequence
>data.
>
>See also Veronique Barriel' 97 paper, (Pan paniscus and Hominoid
>phylogeny: morphological
>data, molecular data and "total evidence" Folia primatologica, 68, 1,
>50-56) which reviews 75 osteological & dental morphological characters,
>and takes into account Schwartz's synapomorphies. The result there also is
>clearly man-chimp clade...

I finally obtained a copy of this paper. I found it interesting in that
their morphological and molecular cladograms were incongruent. According to
their morphology Homo is the sister group to a Pan-Gorilla clade with Pan
being paraphyletic (Pan troglodytes and Gorilla being sister taxa) and the
orangutan next. The molecular tree gave Homo-Pan sister group with gorilla
next, then the gibbon, and then the Orangutan (even this placement appears
to be in conflict with most morphological studies).

Barriel then lumps the molecular and morphology together to make a single
tree which is decided to be the 'total evidence'.

It seems to me that Barriel's paper, while supporting the most popular view
(if the used characters are accepted at face value) still give conflict
between morphology and genes, with the morphology producing results that do
not support a human-chimp sister group).

The paper is further problematic in that apart from the author making a
personal record of chimp characters the traits for other taxa were only
'controlled'. I don't know what this means. There was no citation of
character sources for these taxa and apart from a list of characters used
there was no character table denoting the character states in the different
taxa or a descriptive justification of their distribution. So altogether
this paper does not appear to be very substantiative to decide about human-
ape relationships.

John


Dr. John Grehan
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