A margay cat balances on a seemingly undersized tree branch on Barro Colorado Island. Though only 3,865 acres (1,564 hectares), the island, located in the Panama Canal waterway, is home to an amazing array of flora and fauna, including 1,369 plant species, 93 mammal species, and 366 bird species.

(Text adapted from and photograph shot on assignment for, but not published in, "The Panama Canal Today," February 1978, National Geographic magazine)