Scientists Say: Extinction

This is the permanent loss of a species


This Pinta Island tortoise, named “Lonesome George,” was the last of his subspecies in the Galapagos Islands. He died in 2012, and the Pinta Island tortoise was declared extinct.

Arturo de Frias Marques/Wikimedia Commons (CC SA-3.0)

Extinction (noun, “Ex-STINK-shun”)

This is the end of a species, family or larger group of organisms. Scientists usually say a species is extinct when the last member of that species dies. But the species may have been headed for extinction for years. This can happen when not enough members of the species survive from year to year.

Species might face extinction when there is not enough food for them to survive and reproduce. They might be in danger if the habitat they depend on is changed or destroyed.  Too much hunting or fishing also can push species to extinction. People hunted the flightless dodo to extinction in 1662. Trees such as mahogany can be overharvested. This, too can lead to the danger of extinction. Other species can become extinct because of disease.

To prevent extinction, scientists and conservationists try different approaches. Captive breeding — breeding and raising individuals of a species at risk — is one. Protecting species and their habitats from hunting and fishing is another. Most countries have stopped hunting whales, for example, to save them from extinction. And breeding the California condor allowed it to come back from the brink.

In a sentence

A new count suggests that one million species are currently heading for extinction — and it’s all our fault.

Check out the full list of Scientists Say.

Bethany Brookshire was a longtime staff writer at Science News Explores and is the author of the book Pests: How Humans Create Animal Villains. She has a Ph.D. in physiology and pharmacology and likes to write about neuroscience, biology, climate and more. She thinks Porgs are an invasive species.

More Stories from Science News Explores on Animals