Mollusks, Worms, Sponges, Starfish

Many animals like corals release eggs and sperm into the water on just the right nights of the month.

How Lunar Cycles Guide the Spawning of Sea Creatures

Researchers are starting to understand the biological rhythms that sync worms and corals to phases of the moon

Scientists have discovered the first living C. cooki specimen.

Researchers Find Living Clam Thought to Have Gone Extinct Thousands of Years Ago

While looking for sea slugs in California, a marine ecologist came across the tiny, ten-millimeter mollusks

An artist's renditon of the "alien goldfish." Scientists identified a toothy structure in the animal's gut, suggesting it was some kind of mollusk.

Mysterious ‘Alien Goldfish’ May Have Been a Mollusk

The bizarre creature’s anatomy had stumped scientists for decades

Barnaby Domigan with the giant earthworm

Nine-Year-Old Finds a Three-Foot-Long Earthworm in His Backyard

The New Zealand boy named the creature “Dead Fred”

A species of Chelonaplysilla sea sponge ejects mucus.

Sea Sponges Sneeze Sediment-filled Snot

New research reveals the animals expel mucus as a form of self-cleaning and other creatures eat the stuff up

A giant African land snail

Giant Snails Take Over Florida's Gulf Coast Again

The state has found more than 1,400 of the massive snails since June

Black turban snails are small marine snails that make tasty prey for crabs. Failed crab attacks leave scars on a snail’s shell. By analyzing the rate of scarring and the size of the snail when it was attacked, researchers can learn important details about crab populations.

Scars on Snails Offer a 100,000-Year Record of Crab Populations

A surprisingly simple technique for studying marks on shells shows how California’s crab population has changed over millennia

The offering consisted of 164 starfish, chunks of coral, seashells, pufferfish, a resin figurine, animal bones and the skeleton of a female jaguar holding a spear in its claw.

Cool Finds

Trove of Starfish Deposited as Offering to Aztec War God Found in Mexico City

Researchers discovered 164 sea stars placed in the Templo Mayor around the turn of the 16th century

A flashy jewel bug butt. 

Science Twitter's 'InverteButt Week' Puts Backsides on Display

The behinds of spineless organisms are diverse among species and serve a multitude of purposes beyond expelling waste

Mollusks maintain the symmetry of their pearls by adjusting the thickness of each layer of shimmering nacre. If one layer of the pearl’s nacre is thinner, the next layer is thicker and will balance out irregularities over time to create a smooth, uniform pearl that isn’t lopsided.

How Pearls Obtain Their Remarkable Symmetry

A concept called 'pink noise' brings order to seemingly disorderly patterns seen in classical music, seismic activity, economic markets and even pearls

For a tiny, soft-bodied worm, seeking shelter by way of hermiting behavior likely protected it from predators.

Penis Worms May Have Been the First Real Hermits

Hermit crabs may have evolved hermiting behavior 180 million years ago, but penis worms beat them by more than 300 million years

All mollusks build their own shells.

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How Do Snails Get Their Shells? And More Questions From Our Readers

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Believed to be the world's oldest jewelry, the perforated shells date to about 142,000 years ago.

Cool Finds

Are These Snail Shells the World's Oldest Known Beads?

Found in a Moroccan cave, the prehistoric jewelry dates to between 142,000 and 150,000 years ago

Hammerhead sharks have are considered critically endangered.

More Than a Third of Shark Species Are Now Threatened With Extinction

Overfishing, habitat loss and climate change are behind the 'desperate' decline

Smooth pearls in the shape of orbs and ovals are usually created by bivalves, like mussels, in pearl farms. As with all gems, the less blemishes they have, the more valuable they are.

Smithsonian Voices

The True Story Behind How Pearls Are Made

Mollusks create these shiny gems, but that biological process could change as Earth’s waters warm

A perfect storm of high demand clashing with supply chain issues, worker shortage and delivery problems is forcing restaurant owners to raise seafood prices on their menus.

Seafood Prices Soar Amid Supply Chain Issues and Worker Shortage

As demand for fish rises, restaurants are slammed with employment losses, port congestion, lack of product, rising costs and shipment snags

A present-day orange demosponge (Agelas oroides) can be found off the coast of Corfu, Greece. Research suggests sponges may have lived on Earth 890 million years ago.

This Sponge Fossil May Be the Earliest Record of Animal Life

The 890-million-year-old relic predates periods of extreme cold and the planet’s second oxygenation spike

A healthy crop of mussels lines the coast, exposed during low tide. Mussels will split open when they overheat, such as in June's heat wave.

Pacific Northwest and Canada's Crushing Heat Wave Cooks Millions of Sea Creatures

The estimated death toll could be more than a billion

Just one section of a marine worm with a strange, branching body. This species usually lives inside the many-chambered body of a sea sponge

New Research

This Marine Worm Sprouts Hundreds of Butts—Each With Its Own Eyes and Brain

When it’s time to reproduce, each of the worm’s many rear ends will swim off to get fertilized

The invasive jumping worm will thrash and snap its body when touched.

Highly Invasive Jumping Worms Have Spread to 15 States

The invertebrate depletes topsoil of nutrients and makes it difficult for fungi and plants to grow

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