Thursday, May 28, 2009

mass extinction


One afternoon in Yucatán,
perhaps one night or in the morning,
an asteroid that hit the fan
caused mass extinction without warning,
and the period called Cretaceous
was aborted like the Perm,
and the Ordivician too.
None of these came to full term,
as ours most likely will not do,
judging by the die-off that’s
occurring now to frogs and toads,
and white nose plague that causes bats’
extinction which I fear forebodes
our own. It probably is not
just climate change that threatens this.
The world is often far too hot
and far too cold, and though we’ll miss
the chance of being very cool,
this problem may be less humungous
than one that isn’t minuscule
though microscopic, deadly fungus
killing off amphibians
and bats with white nose in our era
like Taliban, Qaddafi Libyans
and men Al Qaeda trains with terror
to murder, jihadists employed
to keep alive sectarian strife,
and surely as an asteroid
or pathogens, destroy much life.

Mankind is threatened in so many
ways I wonder how long it
can last. It seems that Henny-Penny
was right, as we must now admit.
The sky is falling! Her discourse
is true, and we are doomed to die
like frogs and bats, and dinosaurs,
which I forgot, can’t think why,
perhaps because I do not care
for them as much as for the bats
and frogs and those with whom I share
my life, like people and most cats.

Inspired by an article by Elizabeth Kolbert in The New Yorker, May 25, 2009 (“The Sixth Extinction? There have been five great die-offs in history. This time the cataclysm is us”), who describes how graduate student Karen Lips observed the mysterious disappearance of large numbers of local golden frogs, in the nineteen-nineties, at several locations in Panama and Costa Rica. Whatever was killing Lips’s frogs moved east, like a wave, across Panama. Of the many species that have existed on earth, more than ninety-nine per cent have disappeared. Yet extinction has been a much contested concept. Throughout the eighteenth century, the prevailing view was that species were fixed. Charles Darwin believed extinction happened only slowly, but he was wrong. Over the past half billion years, there have been at least twenty mass extinctions. Five of these—the so-called Big Five—were so devastating that they’re usually put in their own category. The fifth, the end-Cretaceous event, which occurred sixty-five million years ago, exterminated not just the dinosaurs but seventy-five per cent of all species on earth. Once a mass extinction occurs, it takes millions of years for life to recover, and when it does it’s generally with a new cast of characters. In this way, mass extinctions have played a determining role in evolution’s course. It’s now generally agreed among biologists that another mass extinction is under way. If current trends continue, by the end of this century as many as half of earth’s species will be gone. The writer went frog collecting in Chagres National Park with Edgardo Griffith, the director of EVACC (the El Valle Amphibian Conservation Center). About two decades ago, researchers first noticed something odd was happening to amphibians. It’s difficult to say when the current extinction event—sometimes called the sixth extinction— began. Its opening phase appears to have started about fifty thousand years ago, when the first humans migrated across Australia and America. The main culprit in the wavelike series of amphibian crashes is a chytrid fungus, known as Bd. At this point, Bd appears to be unstoppable. Mentions Don Nichols, Allan Pessier, Joyce Longcore, and Rick Speare. In the fossil record, mass extinctions stand out. Mentions Walter Alvarez and the Alvarez hypothesis, which wreaked havoc with the uniformitarian idea of extinction. In 2007, biologist Al Hicks, of the New York State D.E.C., and the National Wildlife Health Center started investigating a series of mysterious bat deaths. Many of the dead bats were discovered with a white substance on their nose, which was cultured and found to be an unidentified fungus. Mentions White-Nose Syndrome (W.N.S.). The writer visited an abandoned mine to study bats with Hicks. One of the puzzles of mass extinction is why, at certain junctures, the resourcefulness of life seems to falter. Just in the last century, carbon dioxide levels in the atmosphere have changed by as much as they normally do in a hundred-thousand-year glacial cycle. In the end, the most deadly aspect of human activity may simply be the pace itself.

© 2009 Gershon Hepner 5/28/09

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