Species of animals or organisms are considered extinct when there are no more of them alive. Animals that are classified as "endangered" are at risk of becoming extinct. Some animals are considered extinct in the wild. This means that the only surviving members of the species live in captivity, like in a zoo.What are some reasons animals become extinct?
Humans are largely responsible when animals become extinct, endangered or threatened. Here are some reasons why animals become endangered: Humans destroy precious habitat--the natural environment of a living thing--when they fill swamps and marshes, dam rivers and cut down trees to build homes, roads and other developments.