Invertebrates

FEATURES

Slideshow
From the giant squid to microscopic squid babies, squids are beautiful and fascinating. As cephalopods, the same family as octopuses and cuttlefish, they have no bones, and swim head-first through the water with their...
Since summer 2013, starfish along both coasts of the United States have been...
Slideshow MORE STORIES Slideshow MORE AUDIO / VIDEO
Tiny plant-like organisms called zooxanthellae live in the tissues of many...
Blog entry MORE STORIES Blog entry MORE AUDIO / VIDEO
I have been at the Smithsonian’s National Museum of Natural History since 1966...

LATEST POSTS

Census of Marine Life researchers discovered this unusual transparent sea cucumber ( Enypniastes sp.) in the Gulf of Mexico at 2,750 meters depth. It creeps forward on its tentacles pretty slowly, at around 2 centimeters per...
Smaller than the head of a pin, this arrow squid (Doryteuthis plei ) embryo...
Anemones are known for serving as homes for Nemo and countless other small...

LEARN MORE

Jellyfish and comb jellies are gelatinous animals that drift through the ocean's water column around the world. They are...
Scientist Martha Nizinski holds a squat lobster ( Eumunida picta ) collected at the Lophelia reefs off Cape Lookout, North Carolina. Squat lobsters are extremely abundant there and are usually found...
Rapa whelks , native to Asia, have invaded the Chesapeake Bay and are raising concerns about economic and ecological impacts to the Bay region due to their shellfish diet. Scientists believe that...
If there had been room to stand up, there would have been a standing ovation. As it was, the five of us on the submersible Curasub clapped and cheered when the first three deep-reef ARMS (Autonomous...
This deep-sea urchin ( Echinocrepis rostrata ) is an important “bulldozer.” It turns over sediment and exposes prey as it moves across the ocean floor, leaving a trail of tracks behind. This photo...
Two California market squids ( Loligo opalescens ) mate in the waters off of California's Channel Islands. While spawning, the male's arms blush red as he embraces the female, a warning to other...
Ochre seastars ( Pisaster ochraceus ) feed on invertebrates, such as coral and shellfish, like the mussels pictured here. The starfish forces open the shell with suction disks on the underside of its...
These newly hatched arrow squid larvae ( Doryteuthis plei ) are each tinier than the head a pin. Free from their yolk sac, they will drift with the current out to sea as zooplankton. Many animals eat...
Like it or not, giant squids are related to snails, clams, and even slugs. They are all mollusks and have soft, fleshy bodies. More can be found in the Giant Squid section .
Boring sponges get a bad rap. Their own name betrays them, announcing to the world that they are unexciting, ordinary and quite frankly, boring. However, if ever a misnomer existed, this is it. More...
In 1874, Reverend Moses Harvey of Newfoundland bought a dead giant squid caught by fishermen. More about the giant squid can be found in our Giant Squid featured story .
Hopefully you've never bitten into a delicious hunk of snow crab meat and instantly spit it out because instead of crab you tasted... aspirin?! If you have, it might have been crab meat infected with...
The over 1,000 species of ribbon worms ( Nemertea ) are mostly found in marine environments (like the Hubrechtia found in a mud flat, in the photo). These worms have both a mouth and an anus (unlike...
A “pink meanie” jellyfish ( Drymonema larsoni )—a species found in the Gulf of Mexico and the Caribbean—feeds on a moon jelly ( Aurelia ). Dr. Keith Bayha from the Dauphin Island Sea Lab and Dr...
When they get larger, Portunus sayi are formidable predators, quick to consume any smaller animal that comes within reach. Fish, other crustaceans, and even smaller members of their own species are...
Most lobsters are a mottled brown color, but sometimes you can see a strange orange or blue lobster. And then, when lobsters are cooked, they turn bright red. Why is there such a rainbow of lobster...
Alien-looking creatures like this deep-red jellyfish ( Crossota norvegica ) swim in the Arctic Sea. Learn more about Arctic sea life in our Under the Arctic Ice story, or at the home page for the...
On many of the dives, Oceana's 2011 Baltic Sea expedition team saw little wildlife in the oxygen-depleted areas. But near some marine protected areas, the crew saw an array of marine life, including...
Dr. Clyde Roper, Smithsonian zoologist and squid expert, tries to measure up to a giant squid specimen (Architeuthis) from New Zealand. The squid wins. More about the giant squid can be found in our...
Subscribe to Invertebrates