'Mafia' Cuckoos Rule By Fear, Foisting Young On Other Birds
A great spotted cuckoo Yathin S Krishnappa via Wikimedia Commons Great spotted cuckoos lay their eggs in other birds' nests, and the host does all the work of raising the impostor. But if the new foster parent doesn't cooperate and ditch the new arrival, the the cuckoo sometimes retaliates, destroying the poor birds' other eggs. Brown-headed cowbirds behave similarly. Whaddaya gonna do about it? Scientists have puzzled over this behavior. This retaliation doesn't at first appear to improve the chance of the cuckoo reproducing, and is slightly risky in that it could lead to a confrontation. One theory to explain it is that the cuckoos are acting like "the mafia," as described in a study published in Scientific Reports--if the host birds fear retaliation, they may raise the cuckoo because it's better than having all their eggs broken. The same reasoning explains why a shopkeep might unwillingly pay for protection from...