You're relaxing on the sofa when suddenly your eyelid starts twitching. Or perhaps it's a muscle in your arm, your leg, or your foot that begins to ...

While Thrinaxodon liorhinus didn’t yet have the sophisticated hearing equipment of modern mammals, it shows that eardrums began evolving earlier than assumed.

Infectious agents can cause muscle twitching and spasms, too. The most commonly known is probably tetanus, which causes a phenomenon called lockjaw, where the neck and jaw muscles contract to the ...