Sea urchins are simple creatures, wandering the seafloor without thought. Or so we thought. They are members of the phylum Echinodermata, which first appeared during the Cambrian explosion. Their list ...

Sea urchins graze on and clean a type of algae that competes with coral, and their decimation is a big reason for the decline of the coral reef ecosystem in the Caribbean. Sea urchins play an ...

Biologists thought that marine heat waves lowered urchin reproduction only at lethal temperatures. A new study shows ...

Since early 2022, sea urchins have been mysteriously dying off across the Caribbean. Now scientists say they have identified the main culprit: a type of relatively large, single-celled marine ...

The pointy shell of sea urchins hides a remarkably complex neural network that resembles the brains of vertebrates, new research suggests.