Anatomy

Japanese scientists videotaped this female giant squid, alive, at the water's surface

Giant Squid

Giant squid live up to their name: the largest giant squid ever recorded by scientists was almost 43 feet (13 meters) long, and may have weighed nearly a ton. You’d think such a huge...
X-ray image of a winghead shark

X-Rays of Fish Reveal Diversity

Scientists in the Division of Fishes at the Smithsonian's National Museum of Natural History use X-ray imaging to study the complex bone structure and diversity of fish. This image gallery showcases X-ray images of...

Clyde Roper On the Over-Sized Anatomy of the Giant Squid

Dr. Clyde Roper discusses the fascinating anatomy of the giant squid ( Architeuthis dux) in this excerpt of "Eyeball to Eyeball," an episode of Errol Morris' First Person television series. Watch Architeuthis and Eyeball...
Aquatic Locomotion of a Sea Lion

How Do Sea Lions Swim?

Sea lions generate thrust, or forward propulsion, by bringing their fore-flippers together in big sweeping motions called “claps.” When a sea lion “claps,” it stretches its flippers out to the sides and sweeps them...
A narwhal breaches the surface, its tusk pointed to the sky

Why a Tusk? The real-life unicorns of the sea and the tusks that make them famous

A narwhal breaching the water's surface, his tusk points to the sky. Male narwhals will sometimes cross their tusks, a behavior called "tusking". Credit: Glenn Williams In the frigid Arctic Ocean , a mysterious...

Why the Octopus Brain is so Extraordinary

An octopus is a lot brainier than you might imagine considering one of its closest living relatives is a sea slug. In fact, some scientists argue it could be the first intelligent being on...