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Re: Lumper or Splitter?
debra mckay (debra.mckay@utoronto.ca)
Wed, 18 Dec 1996 23:02:54 GMT
Phillip Bigelow <bh162@scn.org> wrote:
>debra mckay wrote:
>>
>> dbarnes@liv.ac.uk (Dan Barnes) wrote:
>
>> >As luck would have it I have Bernard Wood's paper from Forli 'Homo habilis:
>snip...
>
>Quoting Wood:
>> >'Taken overall, these results suggest that species which are shown to be closely
>> >related in cladistic studies are not always functionally eqivalent. (snip) [p. 45]
>
>
>> I'm a little confused by the last paragraph, myself. Is he somehow suggesting
>> that there shouldn't be "variation in functional adaptation" within clades?
>
>I think he stated the opposite. Within the theropod clade
>Maniraptoformes, for instance, there is extreme variation in
>functional anatomy between taxa. Within this clade, the
>obvious extremes are birds, which possess a highly apomorphic
>manus, and of course, T. rex, which has an apomorphy exactly
>in the opposite functional "direction" from that of birds.
>Same clade, wildly-different functional morphology.
>
>
>> I didn't know that was a criterion,
>
>It isn't. But such variation happens to crop-up often in
>cladistic studies of non-primate fossils.
No kidding. After further consideration (which hasn't been
easy--it's amazing what a flu bug can do to one's ability
to think...)it seems he's commenting in a (typically) roundabout
way on the amount of homoplasy that plagues hominid cladistic
studies. Especially with craniodental material, which is most
of early hominid fossil material.
I know that some paleoanthropologists (David Pilbeam springs
to mind) reject the notion that useful phylogenetic relationships
can be constructed from cranial material.
Deb
>> but then I'm still on the learning curve
>> wrt this cladistics stuff....
>
>
>Don't feel too bad. Paleotology cut the cladistics-trail. It's taking
>paleoanthropology a while to find the trail. :-)
> <pb>
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