ER-42700 calvaria & -42703 maxilla

F.Spoor cs.2007 Nature 448:688
"Implications of new early Homo fossils from Ileret,
east of Lake Turkana, Kenya"

Some comments:

AFAICS there's no good evidence both fossils belong to different spp:
1) Both fossils don't overlap (calvaria vs.maxilla), so how can they be
placed intp different spp (unless on size arguments) resp. He & Hh??
2) Spoor cs.: "KNM-ER 42703 & the other H.habilis s.s. maxillae lack the
derived morphology of the H.rudolfensis lectotype KNM-ER 1470", but doesn't
even mention Bromage's recent paper
http://www.eurekalert.org/multimedia/pub/3572.php
which re-reconstructs (convicingly IMO) ER-1470 "rudolfensis" as a robust
apith (Ab?). No wonder 42703 & Hh maxillae lack this (inexesting?)
morphology...
3) Suppl.text
http://www.nature.com/nature/journal/v448/n7154/suppinfo/nature05986.html
"Our early Homo hypodigms broadly follow Refs 2 & 7, and differ distinctly
from the interpretation of Ref 4, in which KNM-ER 1470 & OH 65 are
affiliated with the H.habilis type OH 7, to the exclusion of OH 13, OH 24,
OH 62 & KNM-ER 1813. In our view OH 65 is best attributed to H.habilis, and
lacks the derived maxillary morphology of the H.rudolfensis lecto type
KNM-ER 1470 (see main text)."
IOW, their "Hh" is an extremely dubious "species" (existing of He-like
specimens & gracile apith-like specimens??).

I guess 42700 (& 42703 if belonging to the same sp??) could be compared to
the specimen described by R.Potts cs.2004 Science 305:75 "Small
Mid-Pleistocene Hominin Associated with East African Acheulean Technology":
"Hominin fossils from the African mid-Pleistocene are rare despite abundant
Acheulean tools in Africa & apparently African-derived hominins in Eurasia
between 1.0 & 0.5 Ma. Here we describe an African fossil cranium constrained
by 40/39Ar analyses, magnetostratigraphy & sedimentary features to 0.97 to
0.90 Ma, and stratigraphically ass.x Acheulean handaxes. Although the
cranium represents possibly the smallest adult or near-adult known between
1.7 & 0.5 Ma, it retains features observed in larger H.erectus individuals,
yet shows a distinct suite of traits indicative of wide population variation
in the hominins of this period."
This specimen was found next to amphibians & Otomys, and like 42700, had a
thin vault, but keeling. IMO, it's to be expected that inland He developed
smaller bodies & thinner skull vaults.
IOW we can't conclude from this that He was highly dimorphic (the Dmanisi
material is more convincing in this respect), only that different He-like
populations could differ considerably.

Spoor cs. say that He & Hh co-existed for a long time. Not unlikely if Hh
s.s.(eg, OH-62) were gracile apiths.

--Marc Verhaegen
http://groups.yahoo.com/group/AAT
http://users.ugent.be/~mvaneech/outthere.htm
http://users.ugent.be/~mvaneech/Fil/Verhaegen_Human_Evolution.html

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