Re: chimps on the savanna? Nooooo.....

Alex Duncan (
26 Oct 1995 01:34:10 GMT

In article <> H. M. Hubey, writes:

>>The A. afarensis fossils that are available show no evidence whatsoever
>>of adaptation to aquatic environments.
>Once again....
>What do you want to see?
>Dorsal Fins??
>Big Flat feet like Flippers....
>Loooooong fingers (possibly with webbing).....

Nothing so drastic. I would expect to see that measures of hind limb
robusticity don't correlate well w/ estimates of body mass taken from
other parts of the body. Since these hypothetical animals are spending a
lot of time in the water, they won't be supporting much weight over their
hind limbs. Therefore, weight estimates derived from hind limb
parameters such as femoral midshaft diameter or femoral head articular
surface area should be too small when compared to estimates from other
methods. I would expect that femoral heads might be more cylindrical
than in most other primates, as life in the water should lead to largely
parasagittal movements of the hindlimbs. I would not expect to see
anteroposterior expansion of the femoral condyles. I would expect to see
evidence for a capacity for extreme plantar flexion at the tibiotalar
joint. I would expect to see evidence that full extension occurred at
both the hip and the knee during the locomotion cycle.

I don't see any of these things.

Alex Duncan
Dept. of Anthropology
University of Texas at Austin
Austin, TX 78712-1086