How selfish is a cuckoo chick?

We studied the begging display of nestling cuckoos, Cuculus canorus, reared by reed warbler, Acrocephalus scirpaceus, hosts, to test various hypotheses for the cuckoo's unusually rapid begging call. The hypotheses are not mutually exclusive but focus on different parts of the chain: chick need-begging signals-provisioning by hosts. We reject two hypotheses… (More)