There are approximately 4,740 species of frog in the world, each one more fascinating than the last. Though most live in tropical rainforests, species exist that can live in subarctic climates—take for instance the Alaskan wood frog. Featured in the playlist below, it survives the winter by temporarily freezing itself.
Since the 1950s, frog populations have been on the decline, and some experts believe more than 120 species have gone extinct since the 1980s. The causes of this decline are not fully understood. If not stopped, it could mean the loss of some amazing, uniquely specialized species, such as those featured below.