We Are Witnessing the 6th Extinction

Elizabeth Kolbert presented how species are dying at an alarming rate

Artwork by Mariah Crabb

Artwork by Mariah Crabb

“As a species, we are killers,” said Elizabeth Kolbert, author of “The Sixth Extinction: An Unnatural History” and writer for The New Yorker. She gave a special lecture at the Northrop Auditorium on April 13.


Her Pulitzer-winning book, published in 2014, explains the Earth’s history of mass extinctions and shows her readers that the planet is in the middle of another one, this time man-made. Her work shows how some species can adapt; most cannot adapt to humanity’s impact on the climate and environment and predicts a significant loss of species by the end of the century.


Kolbert in her discussion detailed a study that conducted research on a species of tree, which lives in a very narrow climate range, in the Peruvian Andes. There is current evidence showing that while some tree species have been moving into higher altitudes as the effects of climate change become more apparent, some species migrate as much as several meters per year to get away from climate change effects. However, this isn’t the case for all species. There are some species that have not moved and are thus at risk. This is especially concerning since there are over 1,000 species of trees in this area of the world.


“Pick a leaf of an interesting shape and try to follow it [in the forest] … [you] won’t be able to,” she said of the high diversity of tree species in the Peruvian Andes. Kolbert contrasted the Peruvian Andes to some other areas in the world, such as the Boreal forests in Canada. There are only a couple dozen different species of trees existent in Canada, she said.


Kolbert began the evening with a story of the Alal? bird, or Hawaiian crow. The species, a sacred bird to Hawaiians, is extinct in the wild, and the remaining birds are being bred in facilities to help restore their population. She joked about one of the birds in particular, saying that it “doesn’t seem to self identify as a crow.” Over time, the crow learned to say “I know, I know, I know,” which to Kolbert turned the crow into “an emblem of the mess we’re in.”


Another species on the brink of extinction as a result of human interference, especially in the introduction of invasive species, is the Kakapo. Kolbert said that the flightless parrot used to be widespread in New Zealand, but its population began to decline after the arrival of the Maori. Species introduction into the Kakapa habitat almost resulted in the species’ extinction. Currently, only 126 of its kind are left.


The past major extinctions were surveyed as well. She presented a graph of the past five geologic moments on Earth, from the End-Ordovician to the End-Cretaceous period, and explained each geologic moment represents a three-quarters loss of species on Earth. The End-Ordovician extinction was confined to sea life, and the End-Cretaceous extinction ended all non-avian dinosaur life on Earth. Then, she spoke of the three main ways that humans are accelerating climate change and all of its impacts, especially extinction. Besides geographic distribution, atmospheric changes that humans are responsible for are also affecting the environment in other ways.


The last way is the changes humans are creating in the oceans, specifically, ocean acidification. Net acidity in the oceans has increased as much as 30 percent over the last two centuries. It was particularly interesting to learn that the bodies of water absorb a current total of a million metric tons of CO2 every four hours.


By the year 2100, the pH of all the oceans could be 7.8, which could mean an incredible amount of marine life will be lost.


Kolbert gave a brief overview of another way humans alter the environment entirely unrelated to climate change: species introduction. She discussed events such as the importing of the Pacific rat to New Zealand by the Maori, as a source of food. The introduction of the European rabbit is a more recent example, and for this one, bounties were placed on the rabbits. Funny? Yes. A serious issue? Yes. A solution to the problem? No, not yet.


During the Q&A session afterwards, some points that Kolbert brought up in response to questions were related to climate change. For one question, her answer was focused on governmental and social issues that come with addressing climate change. She said that people seem to be talking past each other—she suggested we simply “put aside how we feel and just do it.”