Re: Lumper or Splitter?

Dan Barnes (
Mon, 16 Dec 1996 17:58:36 GMT

In article <01bbe490$426d3f20$LocalHost@dan-pc>, says...
>In an attempt to inject some *scientific* discussion into this group lets
>have some opinions on the following:
For the sake of time I will answer question 3 now and the others later:

>3. Following on from 1 and 2, do you think that the specimens classified as
>H. habilis are representative of a single species?
As luck would have it I have Bernard Wood's paper from Forli 'Homo habilis:
Variability and its significance'. Within this he states:

'When variation within the regions and timebands is considered the most
parsimonious conclusion is that while there is apprently only one early Homo
taxon at Olduvai, there are multiple taxa in the Koobi Fora sample' [p. 42]

'...the hypodigm from Koobi Fora most probably samples more than one, and
probably two, species of early Homo not counting H. ergaster. The same data
suggest that these two taxa are marginally more likely to be synchronic than
time succesive' [p. 42]

He then goes on to conclude that:

'The identity of the second early Homo taxon at Koobi Fora is a more complex
problem' After discounting the possibility of it being placed with ergaster he
says 'The cranium KNM-ER 1470 has already been proposed as the type
specimen of a new species, H. rudolfensis, by Aleveev (1986). If H. rudolfensis
is a 'good' species, and it seems to be in that it was promulgated correctly with
respect to the ICZN, then the second early Homo taxon at Koobi Fora is H.
rudolfensis Alexeev, 1986.' [p. 43]

He also sees nothing within the postcrania to contradict this conclusion.

Although early hominids are not my field I would tend to agree with Wood up to
this point. However, I am unsure about the concluding statement:

'Taken overall, these results suggest that species which are shown to be closely
related in cladistic studies are not always functionally eqivalent. This, in turn,
implies that if the clades are an accurate reflection of phylogenetic history, then
there is as much variation in functional adaptation within clades as there is
between them. It also calls into question the wisdom of continuing to include
either Homo habilis or Homo rudolfensis within the genus Homo' [p. 45]

I hope this has given everyone something to chew on.