The playful North American river otter is equally at home in the water and on land. It makes its home in a burrow near the water's edge, and can thrive in river, lake, swamp, or estuary ecosystems.

caballus, were brought back to North America, first in the Virgin Islands, and, in 1519, they were reintroduced on the continent, in modern-day Mexico, from where they radiated throughout the American ...

Although the bears in ice age North America were the biggest and most powerful carnivores, they had some stiff competition. Twenty thousand years ago, lions roamed the entire planet. The American ...

North American species like the Colorado potato beetle and the fall armyworm have become invasive elsewhere. Illustration by Marilyn Foehrenbach Q: In North America, we worry about invasive ...