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...
These baby olive ridleys ( Lepidochelys olivacea ) will eventually provide a home to crustaceans, mollusks, and other epibionts. That's according to a survey of epibionts living on mature, nesting...
The mauve stinger’s ( Pelagia noctiluca ) name in German means “night light,” referring to the jelly’s reddish coloring and its bioluminescence, the display of light by a living creature. Unlike a...
Like its terrestrial namesake, the Venus fly-trap anemone ( Actinoscyphia sp.) sits quietly and waits for food to drift into its outstretched tentacles, which are lined with stinging harpoons called...
A sea star , Hymenaster pellucidus , brought up from a benthic ROV dive. View the “Under Arctic Ice” photo essay to learn more.
Sea butterflies (also called pteropods) are sea snails aptly named: they are shelled marine snails, each with a foot like a wing, that swim in the water column like butterflies. This one, Atlanta...
Polarized sunglasses have become the norm for humans when they want to filter out the strong glare from the sunlight bouncing off of water in a horizontal direction. But how do animals do that live...
Hermit crabs, like this one collected in Moorea, usually protect their soft, vulnerable abdomens from predators by reusing empty snail shells. They are picky home owners and they will trade shells...
Like other cephalopods, the common cuttlefish ( Sepia officials ) is no dummy. But while octopuses are quick to learn manual tasks like opening jars, cuttlefish have a different skillset: the social...
In the Coral Triangle, a biodiverse area between Indonesia and the Philippines, scientists discovered this swimming polychaete (bristly worm), which they have dubbed the "squidworm." Using a remotely...
This crab ( Neolithodes sp. ) was collected on a NOAA/MAR-ECO cruise to the Mid-Atlantic Ridge in the summer of 2009. Its red color provides camouflage and protection from predators. Red wavelengths...
An octopus shoots ink in defense as it swims away from a scuba diver.
Zombie worms ( Osedax roseus ) eat away at the bones of a dead whale that has fallen to the seafloor in Sagami Bay, Japan. These bizarre worms rely on whale bones for energy and are what scientists...
Home is where the hull is: Since the dawn of seafaring, humankind has had to deal with pesky creatures, such as barnacles, that “foul” ship hulls and boat propellers like this one. Find out more in...
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...
The feathery strands at the back of this nudibranch’s ( Chromodoris willani ) body are no mere adornment: they’re its gills! Nudibranchs, shell-less snails or sea slugs, are named for these tufted...
Last September, the Citizens of the Sea blog series brought you a story of doom and gloom from the reefs of Bocas del Toro, Panama. That is the time of year we typically study -- and celebrate -- the...
A rockfish finds refuge in a deep-sea coral—a red tree coral of the Primnoidae family in the Olympic Coast National Marine Sanctuary. Learn more about deep-sea coral reef ecosystems in our Deep-sea...
Shellfish from the Chesapeake Bay are prized by seafood lovers. But the Bay's ecosystem and fisheries are threatened by human disturbances, including the introduction of non-native species. Non-...
Subscribe to Invertebrates