Echinoderms: Related Content

On Biodiversity: Understanding its Meaning and Importance

The ocean is home to a phenomenal diversity of marine organisms. They have evolved to inhabit warm waters near the equator and the icy waters of the Earth’s poles. Marine life takes advantage of the enormous volume the ocean comprises: from diatoms living near the sunny surface, to octopods living in the dark deep sea.

Diverse Deep-Sea Corals

Shown here are several deep-sea coral species: From left to right is an unidentified purple octocoral, a small gold acanthorgorgiid octocoral, and a large colony of pink Corallium secundum.

Diverse Deep-Sea Coral Community

A diversity of deep-sea corals—including primnoid coral (Narella sp.), black coral (Trissopathes pseudtristicha), and feather stars (Florometra serratissima)—flourish 2,669 m (8,757 ft) deep on the pristine Davidson Seamount off the coast of California. Explore more in the multimedia feature "Coral Gardens of the Deep Sea."

Tide Pools and Adaptations

Adaptation is the key word if you are looking to survive in a tide pool, a space that some scientists describe as the most competitive real estate in the ocean.

Tide pools are exposed to the water's ebb and flow, and plants and animals must adapt to survive wave turbulence, desiccation stress, predation, and competition for space and food. Not enough real estate on the rocks? Barnacles, sponges, bryozoan, and other animals live on top of whatever or whomever they can latch onto.

A Plague of Sea Stars

Sea stars are important members of marine ecosystems, especially in the tropics. We may think of tropical coral reefs as being home mainly to fish and corals, but in fact these habitats are home to a huge diversity of ecologically important invertebrates.

Sometimes, human influences can throw off the balance between these invertebrates, resulting in a cascade effect that negatively affects the entire coral reef ecosystem.

Dazzling New Sea Urchin Species

Simon Coppard, a post-doctoral research fellow at the Smithsonian Tropical Research Institute in Panama and an Encyclopedia of Life Rubenstein Fellow specializing in echinoids often uncovers new species during his research.

The Invisible Loss: The Impacts of Oil You Do Not See

Since late April, the world has watched a devastating oil spill from a BP drilling rig spread throughout the Gulf of Mexico and become one of the worst environmental disasters in the history of the United States.

Invertebrates from the Gulf of Mexico

The Smithsonian's Department of Invertebrate Zoology has a collection of over 57,000 specimens from over 5,700 sites in the Gulf of Mexico. Below is a tiny sample.

Feather Star

As it clings to a red sea fan, a feather star (Cenometra bella) gently waves its slender arms—filtering bits of food from the water. Also known as sea lilies, feather stars are related to sea stars. Learn more about life on coral reefs in the Coral Reefs section.

Manning Seamount Deep Coral Community

Colorful corals and brittlestars inhabit the Manning Seamount in the Atlantic Ocean, far off the coast of New England. Here you can see golden-colored coral (Enallopsamia rostrata), pinkish-brown coral (Solenosmilia variabilis), pink soft coral (Candidella imbricate), and brittlestars (Ophiacantha sp.).

Seamounts: Underwater Oases

Thousands of seamounts—most of them undersea volcanoes—tower above the muddy seafloor. They provide something hard to come by in the deep ocean: a solid surface to cling to. Corals, sponges, and other marine animals attach themselves in dense colonies to seamount slopes. As the animals grow and reproduce, they create three-dimensional structures that provide homes for other creatures. Crabs, sea lilies, and brittle stars climb aboard to gather food. Currents well up and swirl around, serving up a constant supply of nutrients and plankton.

Sea Star on Coral at Seamount

A bright orange sea star (Novodinia antillensis) clings to a large white soft coral (Paragorgia sp.). This photo was taken on the Manning Seamount at a depth of 1,350 meters (4,429 feet) by the remotely-operated vehicle (ROV) Hercules. To learn more about life in the deep ocean, visit the Deep Ocean Exploration section.