The New York Times recently ran a richly-illustrated story on the threats climate change poses to the extraordinary life forms of the Galapagos Islands. With my wife Lisa, I had the good fortune to visit the Galapagos in November, on the way to the annual meeting of the Montreal Protocol, the treaty that saved the ozone layer, in Quito, Ecuador. I also read two deeply thought-provoking books on evolution this year. Herewith my travelogue and book report.
The Galapagos, as we all know, is the place that stimulated Charles Darwin’s theories of evolution. And though battered by human abuse over several hundred years, the islands still hold most of the unique and rich ecological diversity that opened Darwin’s eyes.
Amazing animals and birds abound. I’ll spare you my hundreds of pictures, but a few favorites are inserted here. Blue and red footed boobies, and the northern-most species of penguins.
Sea lions, ungainly on land, swimming effortlessly.
Cacti in every shape and size. Iguanas unlike any others, some adapted for land, and others for swimming in the ocean. Ditto for giant land tortoises and sea turtles.
A hammerhead shark swam a few feet below me.
Most marvelously, these creatures show no fear of, or even took notice of, we humans. The Washington, D.C., squirrel that did not run for cover got eaten long ago. Not so in the Galapagos, where you can approach within inches.
That lack of fear served them poorly when whalers, pirates, and settlers arrived, who ate some species to extinction, brought invasive goats and rats, and committed myriad other sins, including running a lethal, slave-labor penal colony.
In recent decades, Ecuador has moved to manage the islands far more soundly, preserving both natural wonders and tourist assets. But two towns have grown almost exponentially before in-migration was slowed, putting humans and animals in interesting relationships.
While on the boat, I read Jonathan Weiner’s 1994 The Beak of the Finch: A Story of Evolution in Our Time (Vintage Books). He traces the work of two scientists who returned each year for two decades to this forbidding island, Daphne Major, to document evolutionary changes in Darwin’s finches in response to the stresses and opportunities of El Nino-induced weather extremes. Some varieties and species nearly disappeared. Others changed and even merged in surprising ways. All at a pace Darwin himself thought impossibly fast.
In 1994, Weiner saw the looming threat that climate changes would push these extremes to new extremes, further threatening these species’ capacity to adapt even at the faster pace these scientists showed evolution can work:
“This now-notorious global warming began around the time of Darwin’s death, in the 1880s, and it became strongly marked by the close of the 1980s, which was … ‘undoubtedly the warmest decade of the century.' …
“It is no exaggeration to say that a lasting change in the ocean currents—especially a change in the intensity or the frequency of El Nino—would change the course of evolution in Darwin’s islands. And the islands sit in a spot were even a slight global warming could make an enormous and early difference.”
Sigh. It’s 24 years later. As the IPCC and National Climate Assessment reminded us this year, we have much work to do and little time left to do it.
I also recommend Richard Prum’s The Evolution of Beauty (Doubleday 2017). Prum writes of Darwin’s second theory, squelched in Victorian England and largely forgotten until the feminist movement of the latter 20th century. In addition to evolution by natural selection, Darwin theorized a second force, evolution by sexual selection, driven by aesthetic mate choice.
Birds, Prum shows, select the mates they find most beautiful, and evolution obliges by moving species’ physical forms and behaviors accordingly. Preferences, forms, and behaviors evolve in tandem. The power of aesthetic preference can run counter to, and even overwhelm, selection based on fitness, leading some species to evolve themselves toward extinction even in a stable environment.
Selection based on aesthetic and sexual preference, Prum shows, explains many of the marked differences between humans and their primate cousins. Trust me, it’s a good read.
Happy New Year.