Re: Here we go again
Jonathan E. Feinstein (firstname.lastname@example.org)
Wed, 21 Dec 1994 02:34:13 GMT
In article <email@example.com>, firstname.lastname@example.org (The most fearsome bunny rabbit in all the land) writes:
> Hi, folks. In post #1434, J. Feinstein suggested that the "aquatic ape is
>_us_ (i.e. members of _Homo_). I think that this idea has a great deal of
>merit and deserves discussion. P. Wheeler and C. Ruff have shown that _Homo_
>has a more linear physique, with more surface area for volume, than an
>_Australopithecus_ of an equivalent mass. They argue that these features are
>adaptations for foraging and scavenging in a hot, dry habitat. I agree. Yet
>these are the sorts of characteristics that we associate with modern human
>swimmers (assuming that the water is not too cold)--lean bodies, long legs
>relative to trunk. Other characteristics of _Homo_ that distinguish it from
>_Australopithecus_, such as thorax shape and ankle structure, seems to be
>associated with aquatic activity.
> I am NOT suggesting that _Homo_ has "aquatic adaptations"; rather that we
>have exaptations for aquatic activity, which are missing in apes and
>australopithecines. And around 2.4 myr, when _Homo_ probably speciated from
>_Australopithecus_, our ancestors could have utilized every resource available
>just to survive.
> I know that I have used the terms _Homo_ and _Australopithecus_ fairly
>loosely. By _Homo_ I mean primarily _Homo erectus_, because the data on mass
>and stature in early _Homo_ (i.e. _Homo habilis_ and _Homo rudolfensis_) are
>not complete enough to make predictions about physique and morphology. By
>_Australopithecus_ I mean _A. afarensis_ and _A. africanus_, since the data on
>_A. ramidus_ and _A. aethiopicus_ are almost non-existent and I don't consider
>the robust australopithecines to be relevant to the current discussion.
> I hope this notion stirs you to some more thinking,
Sounds like a good enough place to start. I think, however, we can drop
consideration of _A. africanus_ for the same reasons you cite concerning the
robusts. Dental morphology (enlarged molars) suggests that _A. africanus_
was already well down the evolutionary paths of _A. robustus_ and _A. boisei_.
This point, I realize is still a matter of debate, but dental morphology
seems to have been a fair indicator in hominids so far.
As for the rest, I suggest that this very rough hypothesis can be proven
or disproven by a determination of whether _H. sapiens_ is more adapted to
aquatic activity that its predecessors or vice versa.
Taken into account should be species currently thought to be in our direct
lineage; _H. erectus_, _H. habilis_, and other early _Homo_, and the early gracile
australopithecines. We should also consider _H. neandertalensis_; are the
Neandertals in our direct line or are they an offshoot on the family tree
much the same as the robust australopithecines? It has been suggested that
Neandertals were, on the whole, too heavy and compact to have been good
swimmers, but is that so?
I think we have a lot to discuss here if anyone else is willing.
Immortality is something you need to grow into.