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20-Jun-2006
Extinction, from Kim Zussman

Thirteen thousand years ago, on the channel islands off the coast of present Santa Barbara, a pony-sized elephant breathed his last breath. Pygmy species are thought to be evolutionary adaptations to harsh conditions and sparse food, and similar transformations have been observed in other species.

Mastodons and other mammals once common to north America went extinct about 11000 years ago, around the time of recession of the last ice age. It is unclear whether climatic changes explained their demise, but the die off of species lasted many thousands of years.

It seems that successful species must commit and develop biological inertia in order to thrive, in the collection of energy and dispersal of genome, within their places and times. Whereas small changes in climate or food sources can be accommodated by adaptive strategies and migrations, large changes over short periods kill off entire species.

The inertia is a powerful force. One can envision how lush vegetation fed by regular heavy rains will support vast animal life for millennia. Or how, after not too many decades of drought and desertification, feeding and reproduction of many forms will have ended forever.

The mastodons lie in stone state now, in commemoration of their struggle and inevitable demise. Like all fossil life, they bear sculpted witness to each little piece we all contribute to the world. Were their consciousnesses floating free somewhere in the aether it is doubtful their mortal spirit to live would be subsumed by the honor of becoming the rock.

Yishen Kuik adds:

In the latest National Geographic, a tribute is paid to Peter Benchley, who penned Jaws. In the movie, Richard Dreyfus (Hooper) marvels:

Mr. Vaughn, what we are dealing with here is a perfect engine, ah, an eating machine. It's really a miracle of evolution. All this machine does is swim and eat and make little sharks. And that's all. Now why don't you take a long close look at this sign. Those proportions are correct.

The shark apparently has remained largely unmodified over the millennia - the exception that proves to rule of adaptation to ever changing cycles. Are there strategies that are like sharks - the rare ideas that can survive unmodified for extensive periods of time even as the market shape shifts through its cycles?