Normally, when a species loses its primary food source, its numbers begin to decline, even if that species has also lost a key predator. But purple sea urchins are different. Even after they’ve ...

Scientists are racing to save sea stars from extinction through breeding. Here's what they're learning about the different species—from arm-wrestling bat stars to bloodless blood stars.

explain how adaptations of animals enable them to survive in different environments. Sea stars, sea urchins ... and some species of sea stars are even able to grow a new body from a severed ...

Scientists have been looking for ways to combat the spread of sea urchins. Ensuring healthy populations of predators is one ...

California's offshore seafloors have been missing a massive, colorful predator that keeps kelp-munching sea urchins in check.

A mysterious disease nearly wiped out sunflower stars in 2013. But sunflower stars may once again dot the seabed, thanks to ...