Friday, March 4, 2011
The extinction of species is to be expected in a violent universe; that's
why we have paleontologists. They have identified five mass extinctions
over the past 540 million years in which the number of species declined by
over 75% in a geologically brief interval. These mass extinctions mark the
end of the Ordovician, Devonian, Permian, Triassic and Cretaceous Periods.
Recovery from each of these episodes took millions of years. There is a
growing conviction among paleobiologists that Earth is on the brink of mass
extinction-six. The only exception is Homo sapiens. By any measure, Homo
sapiens is thriving at the expense of wild species. Now numbering almost
seven billion, the population has doubled since Paul Ehrlich published the
Population Bomb (Oxford, 1968) which warned of mass starvation by the turn-
of-the-century. Ironically, the developed nations are today confronted
with an obesity epidemic
A review article in yesterday's Nature by Barnosky et al. at UC Berkeley
asks, "Has the Earth's sixth mass extinction already arrived? The article
answers in the affirmative. The current extinction crisis, number six,
unlike previous episodes, results from the actions of a single species,
Homo sapiens. The evidence is everywhere, global warming, enormous ocean
garbage patches, destruction of the great ocean fisheries, deforestation,
etc. Of the 5,487 known species in the class Mammalia, for example, 1,141
are considered by the International Union for Conservation of Nature (IUCN)
to be "threatened with extinction." The ancient concept of a "Balance of
Nature," described by Herodotus in 425BC, is still frequently invoked to
explain apparent homeostasis between species. But there is no homeostasis;
it was simply an illusion created by the short lifespan of humans. That's
why we have paleontologists. The balance-of-nature gave way to
Darwin's "origin of species by natural selection" in 1858. There are still
frequent references to the Balance of Nature by those who don't understand
evolution. More recently, the Gaia hypothesis has developed a following.
Its a more spiritual version of homeostasis in which Earth is viewed as a
single organism. That seems to imply a plan, which would put Gaia in the
category of superstition.
Yesterday, the British National Archives released thousands of pages of
files related to UFO sightings. The only mystery is why this crap was kept
secret or kept at all. It served only to fuel the UFO myth. Within hours
of the release, a new cover-up had emerged. The British government
admitted that the files on the Rendlesham Forest Incident have
disappeared. That must be the file with the unequivocal evidence of a
space-alien conspiracy. I was sympathetic. A decade earlier, pressured by
Rep. Stephen Schiff (NM), the US Air Force sent everything it had on UFOs,
to the US National Archives in a number of huge wooden crates. Along with
a historian, I was asked to be present when the crates were opened and
verify that the contents were not tampered with. In addition to paper,
there were films and photographs and some hardware. Much of it seemed to
have little or no connection to the UFO controversy. That so much could
have been made of so little, indeed of nothing at all, continues to amaze
me.
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