Why We Care
An animal's extinction can interfere with nature's order and eventually harm people.
By Karen Fanning
The large cats are just one of thousands of species that have disappeared from the planet. Their absence not only leaves the world a little quieter, it also disrupts the balance of nature.
"Each species is unique," says John Fay, a biologist with the U.S. Fish and Wildlife Service. "Whenever you lose a species completely through extinction, you've lost a unique element of the system. It will disturb whatever relationships there are within the system. It changes what goes on out in nature."
Because each species' role is unique and cannot be replaced by another species, an animal's disappearance can interfere with nature's order. Even when an animal avoids extinction, its shrinking population can have an unsettling effect on an ecosystem.
Take the elephant, one of roughly 900 endangered animals worldwide. These giant mammals clear large areas of forest, which allow light-hungry plants to grow. These plants are an important food source for grazing animals. Wells dug by elephants are also used by other thirsty animals. If elephants were to vanish, it would spell trouble for other wildlife.
Many of the animals in jeopardy today live in the United States. By the 1930s, the gray wolf disappeared from Yellowstone Park. Because its main predator was gone, the elk population in Yellowstone exploded. Elk began eating the seedlings and saplings of native trees, which prevented the reproduction of forests. But thanks to the reintroduction of the gray wolf over the past decade, the decline of Yellowstone's trees has been reversed.
A Natural Event
Natural extinction is not a bad thing, says Fay. "It's a natural part of nature," he says. "What is alarming is that we seem to be on a path of increasing rates of extinction. Previously when the rate of extinction was greatly increased, there was a question about what caused it. With this current trend, there's not much question about what's causing it. It's us."
Humans have, indeed, played an important role in accelerating the extinction process. Construction, hunting, and pollution have forever changed our environment. In the end, we humans may be the biggest losers.
"Nature is very resilient," says Fay. "But the state of nature that has supported us as a species may be altered in ways that will make it very unsuitable for humans."