Mollusks, Worms, Sponges, Starfish

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

Shallow-water imperial cone snails collected for the study were generally larger than the snails collected in deeper water, suggesting they may be separate species.

New Research

This Snail's Venom Mimics Pheromones to Lure Prey With Sex

The mini mollusk may use a 'siren call' strategy to entice marine worms out of hiding

A tiny, invasive zebra mussel found on a moss ball sold as aquarium decor in a pet store. Officials say moss balls containing the invasive species have been reported in pet stores in at least 21 states.

Officials Say Invasive Zebra Mussels Are Hiding in Aquarium Decor Sold Across U.S.

Pet stores in 21 states recall items after reports of the destructive bivalves lurking in moss balls

C. elegans are roundworms that are about one millimeter long and commonly used in scientific experiments as model organisms.

New Research

These Worms Have No Eyes, but They Avoid the Color Blue

When a scientist noticed that blind nematodes avoid bacteria that make blue toxin, he wondered if they took color into account

“There’s all sorts of reasons they shouldn’t be there,” says British Antarctic Survey biologist Huw Griffiths

New Research

Mysterious Sponges Live on a Boulder Under 3,000 Feet of Antarctic Ice

When scientists aiming to collect a sediment sample were stopped by a boulder, they found unexpected life instead

The worms that burrowed in these tunnels may have been the ancestors of modern Bobbit worms, Eunice aphtoditois, and is the earliest known fossil of an ambush predator

Enormous Prehistoric Marine Worms' Lair Discovered Along Sea Floor

Trace fossils suggest that sand strikers drilled these underground tunnels

This year's top ten titles explore the cosmos, fear and cleanliness alongside narratives about owls, fish and eels.

The Ten Best Science Books of 2020

New titles explore the mysterious lives of eels, the science of fear and our connections to the stars

Dr. Frederieke Kroon looking at a crown-of-thorns starfish on the Great Barrier Reef.

New Research

What Eats the Crown-of-Thorns Starfish? The Evidence Is in the Poop

The sea creatures are the second-biggest threat to the Great Barrier Reef after tropical cyclones

These 'Elvis Worms' Shimmer and Sparkle—and Fight Rough

New research describes four species of iridescent deep-sea creatures that sparkle like bedazzled Elvis Presley jumpsuits

Comb jelly larvae, highlighted by red arrows, shown inside an adult.

New Research

Invasive Comb Jellies Might Overproduce Babies in Summer to Eat Them in Winter

Comb jellies might have evolved to eat their young when prey runs out, but some experts are skeptical of the strategy

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