The ostrich, the world’s biggest flightless bird, does pose some threat to humans. There are documented cases of people being kicked by the ostrich’s powerful legs, resulting in serious injuries.

The ancestors of German cockroaches pestered people about 2,000 years ago far from Germany, a study found. Here’s how the critters achieved global domination.

German cockroaches, scientifically known as Blattella germanica, are ubiquitous in cities in the United States and around the world. The hardy pests first appeared in scientific records from 250 years ...