It's not what you do, it's how readily you do it. Rapid evolutionary change might have more to do with how easily a key innovation can be gained or lost rather than with the innovation itself, ...

drawing of green, scaly fish against blue background© Apokryltaros/CC-BY-SA These days, all fish have teeth. The shapes of their teeth vary according to diet, ranging from the little pegs of goldfish ...

University of Washington scientists have made a remarkable discovery: real teeth growing on the forehead of a deep-sea ratfish. This finding sheds light on the unique adaptations in fish anatomy, ...

These days, all fish have teeth. The shapes of their teeth vary according to diet, ranging from the little pegs of goldfish to the formidable, pointed teeth of sharks. But fish evolved from toothless ...