Re: Bipedalism and theorizing... was Re: Morgan and creationists
Karen (karen@uab.edu)
Mon, 08 Jul 1996 19:11:49 GMT
rfoy@netcom.com (Richard Foy) wrote:
>:In article <31E0E0D4.7D84@hgu.mrc.ac.uk>,
>:James Borrett <jamesb@hgu.mrc.ac.uk> wrote:
>:>Richard Foy wrote:
>:>>
>:>> In article <31DB42FC.2D23@chattanooga.net>,
>:>> Wallace Neslund <morbidia@chattanooga.net> wrote: Due to this, Homo females
>:>> >early on developed a large soft breast to act as a shock absorber to
>:>> >cushion the head and brain. In a feed back loop of larger
>:>> >breasts and better brain growth, Hss females developed the large breast
>:>> >seen today.
As Richard stated befoe, it is an interesting speculation. Since
breasts have so far left no evidence as to when they began in the
fossil record, it will remain speculation for at least a while. I
will add one little thing to the speculation about female breast
enlargement in h.s.s. It is likely that if enlarged breasts was an
adaptive feature of female h.s.s., that the evolution of such a trait
did not hinge on one factor and probably had several contributing
factors.
>:>
>:>
>:>Elaine Morgan suggested in "The Descent Of Woman" in 1972 that the human
>:>female breast shape evolved because we lost our hair, so the babies could
>:>no longer hold on and pull themsleves to the nipple when being
>:>breast-fed, so the breast shape gives them something to hold onto and
>:>makes the nipple more accessible. (She then went on to compare the breast
>:>shape of humans with the breast shape of dugongs).
I don't know about all infants but I have never seen a h.s.s. infant
hold on to its' mothers' breasts. If it turned out that this was a
factor in the development of enlarged breast tissue in h.s.s., it
would have to be an incredible benefit for an older infant who might
have the capacity to hold on to its' mothers' breasts and then I am
not sure exactly what that benefit would be. It is not as though the
baby could cling to its' mothers' breasts leaving the mothers' hands
free while travelling.
However, I too, suspect that the benefit of the enlargenment of the
breasts probably had something to do with benefit for the infants.
Whatever we come up with on this speculation is only speculation but
I do like the speculation regarding benefits for infant and or mother
better than the speculation that breasts developed as a sexual
selection factor though I can't discount that either. It could be
that I, being female am biased and would simply prefer that type of
scenario!
>:That makes a lot more sense to me than the breast devloped as a
>:result of sexual selection.
It does make sense if you consider what the primary benefit of breasts
in female primates is in the first place. That is one of the reasons
that I do believe that if indeed the breasts developed as an adaptive
trait that it probably did have some benefit to h.s. infants.
Will we ever know the answer to this type of question? Perhaps so.
With the continuing research in genetics, it is possible. Until then,
we continue to speculate.
Karen
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