Something ancient still walks the world’s shorelines—creatures with armored shells and spiky tails that seem plucked from the ...

Because of their origin 450 million years ago, horseshoe crabs are considered living fossils.

Indeed, researchers are coming to realize that the term “living fossil” is a misnomer. One by one, the classic examples—horseshoe crabs, coelacanths, cycads, and more—have turned out to be very ...

A researcher inspects the interior of a male American horseshoe crab at NASA's Kennedy Space Center in Florida. Known ...

The trilobite, an extinct marine arthropod vaguely resembling a horseshoe crab, inhabited the primordial seas that ... in a continental collision 400 million years ago. Studying the fossils of ...

“These living fossils urgently need Endangered Species Act protection. Horseshoe crabs have saved countless human lives, and now we should return the favor.” Horseshoe crabs are brown, body-armored ...