Fans of McDonald’s Filet-O-Fish might find an unwanted surprise in their food — but experts say it’s a good thing.

Scientists have uncovered new clues about some of Earth’s earliest fish, shedding light on the ancient origins of vertebrates ...

The baby fish, which is roughly the size of a pea, was raised from a surprise egg mass discovered at Shedd Aquarium last fall. Experts say the achievement could help reduce pressure on wild frogfish ...

A study reveals how the asexual Amazon molly defies evolutionary expectations — plus, evidence of what might be powering superluminous supernovae.

The tripod fish doesn’t swim much. Instead, it stands on three elongated fins, conserving energy while currents deliver food.

A tiny, yellow-and-orange juvenile warty frogfish rests on a coral-like object in a habitat at Chicago's Shedd Aquarium. A tiny fish is making big waves at Shedd Aquarium as animal caretakers ...