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Re: Archaic H. sapiens???
Ralph L Holloway (rlh2@columbia.edu)
Tue, 7 Jan 1997 18:36:11 -0500
On Tue, 7 Jan 1997, Michael McBroom wrote:
>
> Geez, why didn't you just say so? No I haven't, but I would very much
> like to. I'm heading back up to the campus either today or tomorrow, so
> I thought I'd look up the above journal in our online catalog. No
> luck. I'll have to get a copy of your article through Inter-Library
> Loan. Unless you can direct me to a source where it might be on the
> 'net.
You might have trouble finding it, as the journal died in 1986. I'm out of
reprints or I'd send you one.
>
> I guess I should have been more clear. Of the books I have in my
> personal library, I have been able to find four (I probably have others)
> in which Broca's area in H. habilis is discussed. The four books are
> the ones I've listed above. Of those four books, Leakey and Lewin, and
> Walker and Shipman discuss the evidence for Broca's area in 1470.
> Bickerton and Pinker do not cite specific specimens within the text of
> their books. Based on your prompting, though, I checked the chapter
> notes and found out a bit more. Bickerton doesn't discuss Broca's area
> specifically in the chapter notes, but he does have this to say: "With
> regard to brain content, fossil hominids show more marked hemispheric
> asymmetries than contemporary apes (Holloway and de la Coste-Lareymondie
> 1982)." And I see that the title of your paper is "Brain endocast
> asymmetry in pongids and hominids: Some preliminary findings on the
> palaentology of cerebral dominance." _American Journal of Physical
> Anthropology_ 58:101-10. Might this be the source he used?
>
> Regarding Homo habilis, on page 353 in Pinker (1994), the author writes:
> "Broca's area is large and prominent enough to be visible, as are the
> supramarginal and angular gyri . . ., and these areas are larger in the
> left hemisphere." His apparent sources for this are Stringer & Andrews
> (1988): "Genetic and fossil evidence for the origin of modern humans.
> _Science_, 239, 1263-1268; and Stringer (1990) "The emergence of modern
> humans." _Scientific American_, December.
Pinker must have been citing Tobias' 1987 JHE article, and then the
chapter in his two volume work on habilines. Stringer and Andrews would be
using the same references. As I said in previous posts, the actual fossil
hominid endocranial evidence is far more difficult to interpret, and
Tobias does not really deal with the issues of deformation and lack of
areas. For example, Tobias insists that there was a left inferior parietal
petalia (Wernickes region, according to Tobias, but not really). Problem
is that the OH7 parietals were found crushed flat, so one should be very
careful when attributing very minor bumps to the brain rather than to the
mechanics of distortion and reconstruction, which I am all too aware of,
having reconstructed so damn many of these things.
>
> All this has prompted me to pull out Tattersall (1995) once again, and
> reread the sections on H. habilis to refresh my memory. I had recalled
> that there was, and apparently still is, some controversy over just
> which specimens really belong to this classification. ER 1470,
> according to Tattersall, when it was assigned to H. habilis, stretched
> the limits that had previously been defined. Then, a year later ER 1813
> is unearthed -- morphologically similar, but with a largely complete,
> although much smaller, cranium. Tattersall mentions that it has been
> generally accepted to be a female of the species. I'm wondering if
> you've had a chance to do an endocast of ER 1813, and if there is any
> evidence of Broca's area there? Later in the book, Tattersall mentions
> Bernard Woods reexamination of the habilines, and agrees with Woods that
> ER 1470 belongs within H. rudolphensis, while ER 1813 should stay where
> "she" is. Based on your previous statements, I take it you do not
> concur with this view?
This a is a matter of some controversy. I have great difficulty with the
taxonomic designations, and will probably go to my grave before I ever am
able to take them seriously. I have a lot of trouble seeing ER 1813 as
simply the female of KNM 1470. It could be, but I see more than just size
differences there (which are really quite extreme: 753ml to 510ml). 1813
does not have these regions intact enough or with enough convolutional
detail to say whether they are present or not.
I don't know what to call 1470 either. I only note that at the moment
it is about the oldest representation of early Homo that we have that has
a full ebrain endocranial cast. I think it is different enough from the
Olduvai stuff to warrant a different disignation, such as H. rudolphensis.
But is 1813 and that real mystery 1805 the same taxon? I think not, but
this isn't my area of expertise. (Incidentally, just as an aside, I am not
"on the fringe" because i regard Neandertals as the same species as
ourselves. This is one of those pendular reactions that sets in
Paleoanthropology now and then, but I do have people in the discipline
with whom I share this perception :-)).)
Finally, you asked about the involvement of Broca's area in language
behavior after citing Walker and Shipma. I think they really oversimplify
the MRI and PET stuff on the brain, but here is a recent reference which
sort of address that matter you raised:
M. Adam et al, 1996 Brain activation modulated by sentence comprehension.
SCIENCE, 274:114-116 (Oct 4 issue). I would be interested in hearing your
reaction as a linguist to that study which certainly heavily implicates
Broca's and Wernickes' on the left side from fMRI.
Ralph Holloway
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