Crossing a beach to get to the sea, a two-foot-tall Humboldt penguin waddles over what appears to be a cluster of large boulders. Suddenly one of the rock-like objects rises up and barks! The penguin ...

The yellow-footed rock wallaby is a marsupial—a pouched mammal—belonging to the same family as the kangaroo. This rock wallaby lives in mountain habitats in isolated portions of Australia. The ...

The head louse makes itself at home on the human scalp, eyebrows, and eyelashes, which is where you’ll find this annoying parasite. An estimated six million or more children are infested each year in ...