The chambered, or pearly, nautilus (Nautilus pompilius) is a charismatic cephalopod species known for its exceptional spiraling, chambered shell. It belongs to a family that has barely changed since ...

Bluefin tuna are an ocean-going fish that grow up to 10 feet long and can weigh as much as 1,200 pounds. Unlike almost all fish, bluefin tuna are warm-blooded and able to regulate their body ...

Three vital provisions give the Act its teeth. It’s “citizen-suit” provision lets public-interest groups and individuals petition and sue sluggish federal agencies to make sure the Act protects ...

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 ...

Oases in the desert, Southwestern streams are among the most delicate ecosystems on the planet. In these shallow, ephemeral waters, species like the Mexican garter snake once carved out a precarious ...

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, ...

Why are bats dying in North America? An estimated 6.7 million bats have died since 2006 because of an outbreak of white-nose syndrome, a fast-moving disease that has wiped out entire colonies and left ...

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 ...

An analysis of oil and gas pipeline safety in the United States reveals a troubling history of spills, contamination, injuries and deaths. This time-lapse video shows pipeline incidents from 1986 to ...

DESCRIPTION: Freshwater mussels are bivalve mollusks that have a two- valved hard shell, a soft body with respiratory, digestive and reproductive organs, and a muscular foot for locomotion, burrowing ...

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 ...

As this keystone species' name suggests, the gopher tortoise is an expert at living underground — like a gopher. Gopher tortoises have shovel-like front legs and strong, thick back legs to help them ...