The number of tigers in the wild has gone up dramatically since 2015 — largely because of improvements in monitoring them, but the species remains endangered.

Leakey made important contributions to our understanding of human origins through his fossil finds. He later gained fame for taking on poachers who threatened to wipe out Kenya's elephants and rhinos.

The number of bald eagles in the lower 48 states has quadrupled since 2009, according to a new survey. The findings are a bright spot in an otherwise troubling picture for American birds.

Dr. Amir Khalil, a veterinarian with Four Paws International, says the "world's loneliest elephant" is settling into his new home in Cambodia. Khalil sang Sinatra's "My Way" to help calm Kaavan.