“We are the asteroid.”
Elizabeth Kolbert, author of the Pulitzer Prize–winning book The Sixth Extinction, delivered an unsugarcoated message about the planet’s speedy demise during a Circle Talk on February 4.
The author explained that the first five extinctions occurred over many millions of years—the first some 450 million years ago and the last, which most scientists agree was an asteroid-induced end to the dinosaur age, about 66 million years ago. Showing example after example—of disappearing species, climbing temperatures, and overacidified oceans—Kolbert explained why she believes we are racing toward the planet’s sixth extinction.
“To say we’re in a sixth extinction is a pretty severe thing to say,” Kolbert acknowledged, then launched into scientific data-laden talk that showed how humans today are “changing the world on an asteroid-like scale.”
One of her key points was about carbon levels and climate change. “We’re warming up the planet and we’re doing it really fast,” Kolbert began. Carbon dioxide levels are at 414 parts per million, radically increased in recent decades, and the last five years are the warmest on record. Kolbert also discussed how climate change is affecting birds, whose confused migration patterns can affect food-gathering and be deadly. “North America has lost one-quarter of its birds since 1970,” she said.
She also discussed rising sea levels and ocean acidification due to excess carbon. Incredulous that some could doubt the chemistry lesson that carbon in water creates carbonic acid—"pretty basic science” understood for 150 years—she explained that oceans have become 30 percent more acidic since the start of the Industrial Revolution. One glaring result: dying coral reefs and struggling populations of shellfish and other creatures that create shells from calcium carbonate. “A lot of scientists are worried that coral reefs will not survive this century,” she warned.
Kolbert also addressed the effect of invasive species, which can leave native species defenseless against the intruders. Early in her lecture, she introduced the ʻalalā, a nearly extinct Hawaiian crow, and the intense measures being taken to protect and repopulate the species. Later she explained that a type of weasel brought in to control rabbits in New Zealand actually ate birds instead. Flashing colorful portraits, she displayed the kakapo, a parrot with a current population of about two hundred, and the takahē, which is down to about four hundred. Citing examples closer to home, Kolbert also spoke about the “white nose syndrome” killing brown bats in New England and elsewhere. The cause: a fungus brought from Europe.
Following the talk was a question-and-answer period, then small discussions in dorms to help students process the messages and consider action steps. “You guys should be pretty angry about what you’re getting handed here," Kolbert told the Groton students. "... My generation has done a really bad job so your generation is going to have to endure the consequences of that."
How those are handled will be literally earth-changing. "How far we can push the natural world and not suffer the consquences is a profound question. I'd would argue it’s the question of the coming century.”
Elizabeth Kolbert’s talk was Groton School's Ron Ridenhour Memorial Lecture, honoring the journalist whose information-gathering while fighting in Vietnam and appeals to Congress resulted in an investigation of the My Lai Massacre. The lecture was created in 2000 by David and Jean Halberstam P'98 and the Fertel Foundation to broaden students' scope of knowledge.