Friday, November 18, 2005


The beginning of one production of Tennessee Williams' play, "Streetcar Named Desire", opens with Stanley, the protagonist, entering and throwing a package of bloody meat on Stella's, his wife's, lap. Thus Stanley brings home the meat. To think of Tennessee Williams and his home base in New Orleans and of that play set in New Orleans, makes my heart ache. I once rode a streetcar name Desire while I was living on the West Bank across from the The Big Easy just to say that I had done it. Read below and you'll understand why I opened this Dawkin's entry as I did. Lots of interesting theorizing.

"Even if this is an exaggeration, it should at least encourage us to look elsewhere for possible benefits of our unusual gait. It arouses the suspicion that, whatever non-locomotor benefits of bipedality we might propose as drivers of its evolution, they probably did not have to fight against strong locomotor costs.

"What might a non-locomotor benefit look like? A stimulating suggestion is the sexual selection theory of Maxine Sheets-Johnstone, of the University of Oregon. She thinks we rose on our hind legs as a means of showing off our penises. Those of us that have penises, that is. Females, in her view, were doing it for the opposite reason: concealing their genitals which, in primates, are more prominently displayed on all fours. This is an appealing idea but I don't carry a torch for it. I mention it only as an example of the kind of thing I mean by a non-locomotor theory. As with so many of these theories, we are left wondering why it would apply to our lineage and not to other apes or monkeys.

"A different set of theories stresses the freeing of the hands as the really important advantage of bipedality. Perhaps we rose on our hind legs, not because that is a good way of getting about, but because of what we were then able to do with our hands—carry food, for instance. Many apes and monkeys feed on plant matter that is widely available but not particularly rich or concentrated, so you must eat as you go, more or less continuously like a cow. Other kinds of food such as meat or large underground tubers are harder to acquire but, when you do find them, they are valuable—worth carrying home in greater quantity than you can eat. When a leopard makes a kill, the first thing it normally does is drag it up a tree and hang it over a branch, where it will be relatively safe from marauding scavengers and can be revisited for meals. The leopard uses its powerful jaws to hold the carcass, needing all four legs to climb the tree. Having much smaller and weaker jaws than a leopard, did our ancestors benefit from the skill of waLking on two legs because it freed their hands for carrying food—perhaps back to a mate or children, or to trade favours with other companions, or to keep in a larder for future needs?

"Incidentally the latter two possibilities may be closer to each other than they appear. The idea (I attribute this inspired way of expressing it to Steven Pinker) is that before the invention of the freezer the best larder for meat was a companion's belly. How so? The meat itself is no longer available, of course, but the goodwill it buys is safe in long-term storage in a companion's brain. Your companion will remember the favour and repay it when fortunes are reversed. (1) Chimpanzees are known to share meat for favours. In historic times, this kind of i.o.u. became tokenized as money.

"A particular version of the 'carrying food home' theory is that of the American anthropologist Owen Lovejoy. He suggests that females would often have been hampered in their foraging by nursing infants, therefore unable to travel far and wide looking for food. The consequent poor nutrition and poor milk production would have delayed weaning. Suckling females are infertile. Any male who feeds a nursing female accelerates the weaning of her current child and brings her into receptiveness earlier. When this happens, she might make her receptiveness especially available to the male whose provisioning accelerated it. So, a male who can bring lots of food home might gain a direct reproductive advantage over a rival male who just eats where he finds. Hence the evolution of bipedalism to free the hands for carrying. —Richard Dawkins, THE ANCESTOR'S TALE, pp. 91-92

"(1) There is a well-developed theory of reciprocal altruism in Darwinism...." p. 92 footnote


How many nights in my life did I walk around and around, suffering over the loss of one woman or another? Are we sure that walking didn’t arise as a stress release mechanism for horny males? Richard Dawkins tells other tales, but the most interesting thing about bipedalism is that it’s the one trait which separates us "superior" humans from all other mammals. Not tool using as once opined. Birds and chimps and other beasts also use tools.

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