Host birds only tolerate parasitic cuckoo eggs in their nests when they fear retaliation

The brown-headed cowbird is nothing short of a nightmare for its hosts: If they eject the brood parasite's eggs from the nest, it punishes them by destroying their entire clutch. Researchers from the Max Planck Institute for Evolutionary Biology in Plön and Harvard University have designed a mathematical model for analyzing the interaction between avian brood parasites and their hosts. The model calculations show that birds only accept a brood parasite's eggs in their nests if they are forc