Fifty thousand years ago, North America was home to towering giants. Mammoths roamed the tundra, saber-toothed cats hunted in ...

This mammal climbs trees by pulling itself up with its front ... mi) ranges that females (24-50 sq. mi). North American densities vary from one black bear per 0.9 - 76 sq. mi. Costello, C. 1992. Black ...

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.

This is especially true for bees, with over one-third of native bee species at risk of extinction. Overall, the new research found that more than 22% of native pollinators in North America are at ...