DURHAM, N.C. -- We humans are fixated on big brains as a proxy for smarts. But headless animals called brittle stars have no brains at all and still manage to learn through experience, new research ...

As mist lingers over a Swedish fjord lined with towering, forested cliffs, a group of scientists collect mud from the bottom of the turquoise-colored waters. They’re after brittle stars—marine animals ...

"You can also find brittle stars, which are close relatives of starfish and live up to their name – they have very long, thin, and brittle arms, which can break easily or the animal will even ...