A new study suggests the platypus and echidna — the only egg-laying mammals — had a water-dwelling ancestor. The finding ...

An analysis of the interior of a single bone suggests its owner was probably an aquatic or semi-aquatic animal. Since the ...

Neither animal has teeth, and though they both produce milk ... time of dinosaurs probably shared a lot more biology with a monotreme than with a horse, a dog, a cat or ourselves.” ...