9.22.2006

I should use this Asia thing to my advantage

Great stuff on the science front! Two days ago (as the subject says, I should really have posted right when I saw the article -- being 12 hours ahead does give me some advantage!), we heard about the find of a 3.3 million year old fossil in Ethiopia of the species Australopithecus Afarensis that is already telling scientists a great deal about how we evolved. Some highlights from the article:

The infant's brain size is estimated at 330 cubic centimeters. This is not much different from that of a similarly aged chimp. However, when compared to adults of her species, she had formed only between 63 and 88 percent of her adult brain size. This is relatively slow brain growth compared to chimps, which by three years of age have formed more than 90 percent of the brain. This rate of brain growth is actually slightly closer to that of humans, possibly pointing to an early shift in human evolution.

Very interesting, I think, that this evidence points to the brain's rate of development slowing before brain size was any bigger than that of a chimp. What would've been the adaptive advantage to a slow-developing brain? Longer dependency on the mother, so bigger size and more likely to survive once the mother quit carrying her everywhere?

The skeleton also shows that she (and thus our ancestors in this period) was walking upright and her toes indicated that she had to be carried and couldn't cling to her mother like a chimp infant. However, the upper skeleton and finger bones, as well as the semicircular canals in her inner ear, showed that she would have been a climber, and that Australopithecus afarensis still lived in the trees.

There's also evidence that her voice sounded much more chimplike than human.

Of course, I posted the link over in my Monster Evolution Debate on Dave's ESL Cafe and my Hare Krishna adversary immediately said it was just evidence of Lord Rama's army of ape-men and started posting pictures of the Adams Bridge...

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