66 million years ago, a fish chewed up and spit out food. It's now a fossil in DenmarkA fossilized regurgitation from a fish 66 million years ago provides insights into predator-prey relationships in the Cretaceous sea.
Cuckoo Chicks Are Sleeper Agents in Evolutionary Arms RaceSpeciation can occur through an arms race between exploiters and victims, leading to mimicry and potentially new species.