Known as “America’s wolf,” red wolves are the only species of wolf that lives in the United States—and nowhere else.

The fennec fox is the smallest of all the world's foxes, weighing only 2.2 pounds (1 kilogram). It has enormous ears, ...

A red-bellied piranha calmly swishes through a river. Suddenly, it spots dinner: a shrimp swimming nearby. The fish glides closer and opens its mouth to reveal rows of razor-sharp, triangular teeth.

Slowly stalking down the snowy hillside, the Amur leopard watches its prey through the trees. In the clearing below, a sika ...

Wherever there is dung (also known as poop), there are most likely dung beetles. They belong to three basic groups: rollers, tunnelers, and dwellers. Those words describe how these beetles use the ...

When you see a snowy owl, it's clear how the bird probably got its name: they're snow-white. Males are generally whiter than females. As males grow older, they get whiter. The females never become ...

The giant squid is massive and when full grown can be at least 33 feet (10 meters) long. These mysterious eight-armed creatures are rarely seen by humans. Most of what we know about them comes from ...

Christmas Island red crabs are famous throughout Australia and the world for their bright red color and for their spectacular annual migration to the sea. Millions of crabs become rivers of red as ...

Youngsters tumble, climb, and run playing follow the leader. Another group plays a rowdy game of king of the mountain. Several adults watch the action, relaxing nearby. Is this a playground scene at ...

Leatherback sea turtles are the biggest turtles on Earth. An adult leatherback sea turtle is generally longer than an average-size man is tall. Unlike other species of sea turtles, which have hard ...