Amphibians and reptiles are amazing creatures with clever adaptations that have allowed them to brave the millennia. Consider the Coachella Valley fringe-toed lizard's scaly hind toes, which resemble ...

DESCRIPTION: Female bald eagles can weigh up to 14 pounds and have wingspans of eight feet. Males weigh up to 10 pounds, with wingspans of six feet. Both sexes have brown bodies and acquire their ...

ETYMOLOGY: The word caribou comes from French explorers of eastern North America who derived it from the Micmac Indian term xalibu, meaning the “one who paws.” This is a reference to the caribou's ...

For every county in the United States, the map below shows information on all the animals and plants protected under the U.S. Endangered Species Act as threatened or endangered. To see the number of ...

Monarch butterflies are important culturally and ecologically across North America. Generations have watched in wonder as yellow-and-black striped caterpillars fold into green-and-gold chrysalises and ...

The grizzly bear is so named because its hair is grizzled, or silver tipped, yet the name is commonly believed to be derived from “grisly,” meaning “horrible.” DESCRIPTION: A subspecies of brown bear, ...

DESCRIPTION: Roughly five feet in length, Mexican gray wolves generally weigh between 50 and 80 pounds. Their coats are buff, gray, and rust colored, often with distinguishing facial patterns. They ...

This 2-foot-long, black-masked member of the weasel family once occurred in central grasslands and basins from southern Canada to Texas but is now one of the most endangered mammals in North America.

With its cryptic coloration and flat body, the flat-tailed horned lizard is capable of disappearing on the desert floor. When a predator threatens, the lizard may run a short distance and then stop ...

The variability among living organisms on the earth, including the variability within and between species and within and between ecosystems. Biological diversity, often shortened to biodiversity, is ...

DESCRIPTION: Walruses are easily distinguished by their long, white tusks, cinnamon-brown skin, grizzled whiskers, and bodies full of blubber. Growing up to 3,750 pounds, male Pacific walruses are ...

Did your childhood include swallowtail and monarch butterflies fluttering through your neighborhood? Caterpillars chewing backyard leaves? Warm summer nights with fireflies blinking in the bushes? The ...