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Rabid reader - 2007-09-14 08:40:37
Rape of Europa is a darn close second. Talk about graceful writing and INTENSIVE research. It also is a feast for the mind, in a totally different way. World Without Us knocked me out of Rape of Europa for the time being...but as soon as WWU is done, it's back to ROE. Both very recommended! Let's see first about glaciation. If I understand your point correctly, you posit that glaciation might have driven off the animals. The time frame in which they disappeared is about 13,000 years ago. WIkipedia says: During the most recent North American glaciation, the Wisconsin glaciation (70,000 to 10,000 years ago), ice sheets extended to about 45 degrees north latitude. These sheets were 3 to 4 km thick. This Wisconsinian glaciation left widespread impacts on the North American landscape. The Great Lakes and the Finger Lakes were carved by ice deepening old valleys. Most of the lakes in Minnesota and Wisconsin were gouged out by glaciers and later filled with glacial meltwaters....[more]. In other words, to my way of thinking--as a non-scientist--is that the glaciation was going on for 60,000 years, yet the megafauna all vanished--70 genera!--within *one millenium* around 13,000 years ago! If the extinctions happened in only one-sixtieth of the time of the whole glaciation, I would tend to think it might not be such a strong factor, barring any extreme temporary weather effect within the entire glaciation period. I am utterly ignorant about the habitat diversity in africa compared to that of north america but I can tell you that that was not a factor in Alan Weisman's answer to this riddle, in his book.
Hint: When Darwin visited the Galapagos Islands, as you know the tortoises were incredibly tame. Compare those to the snapping turtles who have coexisted with humans here in Michigan for a long time [imperfect example! just as a hint!!] "Why aren't Africa's big mammals extinct as well? "Because here, humans and megafauna evolved together. Unlike the unsuspecting American, Australian, Polynesian, and Caribbesn herbivores who had no inkling of how dangerous we were when we unexpectedly arrived, African animals had the chance to adjust as our presence increased. Animals growing up with predators learn to be wary of them, and they evolve ways to elude them...."
I myself was absolutely fascinated to learn that. It sure has the ring of truth, doesn't it? I was kind of pondering it all day. I love learning stuff like that. Anyways, good for Kirk! add your comment: |