A free-flight training that teaches parrots to follow simple commands could help with conservation efforts like safely releasing the birds into the wild.

Mother koalas are transferring a deadly virus that causes immune depletion and cancer to their babies, a new study shows.

Digging into data from decades ago, a new study finds that the size of bird eyes can predict where they live and how they behave.

Living in urban areas is causing many mammals to grow bigger. Lots of available food in areas packed with people may explain why.

A foster system can successfully fledge scarlet macaw chicks that would normally die, an experiment shows.

Three species of weasel, including one considered the world's smallest carnivore, are likely in decline, researchers say.

New research suggests how to conserve rough-nosed horned lizards, which live only in Sri Lankan rainforests.

Biologists have caught a caecilian, a legless amphibian that can be anywhere from a few inches to 5 feet long. It's the first one found in the US.

New research examines the effects of introduced animals on Madagascar’s extinct megafauna, like the elephant bird, dwarf hippo, and giant lemur.

Muskrats are a sort of "canary in the coal mine" for one of the world's largest freshwater deltas, research finds.