Add Yahoo as a preferred source to see more of our stories on Google. A sunflower sea star may be about to snack on some sea urchins in California. Brent Durand/Moment via Getty Images Before 2013, ...

Before 2013, divers on North America's west coast rarely saw purple sea urchins. The spiky animals, which are voracious kelp eaters, were a favorite food of the coast's iconic sunflower sea stars. The ...

Rebecca Vega Thurber does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations ...

(The Conversation is an independent and nonprofit source of news, analysis and commentary from academic experts.) Rebecca Vega Thurber, University of California, Santa Barbara (THE CONVERSATION) ...