Scientists Use Bird-O-Vision to Learn Why Some Cuckoos Are Expert Counterfeiters

: The reproductive life of a cuckoo is both easy---it lays its eggs in others birds' nests, and lets them feed the young---and difficult: cuckoos are involved in an "evolutionary arms race" with other birds, finds a new study. Even as cuckoos improve their counterfeiting skills---producing eggs that look more like others birds'---the host birds get better and better at identifying the forged eggs. How the Heck: