In the case of mammals, the best-studied group of animals, the fossil record indicates that the “background” rate of extinction, the one that prevailed before humans entered the picture ...

While we can’t say exactly how many animal species have gone extinct in the past 125 years, it’s estimated that between 200 and 500 species have faced extinction in the past century.

WASHINGTON— The U.S. Fish and Wildlife Service today finalized a rule removing 21 species from the list of threatened and endangered species under the Endangered Species Act because of extinction. “My ...