As avian embryos develop, they draw needed calcium from the inner most layer of their eggshell, which in turn thins the eggshell and facilitates hatching. Yet, parasitic cuckoos, which lay their eggs ...

It's a risky business being a reed warbler. Not only do these tiny birds embark on an annual migration of some 5,000 km from their West African winter quarters to breeding grounds in the north, but ...

The Cuckoo (Cuculus canorus) is an interspecific brood parasite that mimics the eggs of its hosts. In this study we tested the resemblance between Cuckoo and host eggs in four host species breeding in ...

Interactions between avian hosts and brood parasites can provide a model for how animals adapt to a changing world. Reed warbler (Acrocephalus scirpaceus) hosts employ costly defenses to combat ...

The Massachusetts Audubon Society’s annual spring bird-a-thon last weekend produced reports of many species of spring migrants from a number of locations. The variety was highlighted by a spectacular ...

THE exhausting chore of raising young is one a few birds manage to avoid. By laying their eggs in the nests of others, they dupe those others into feeding their nestlings. Such brood parasitism has ...

This story appears in the January 2018 issue of National Geographic magazine. For the care and feeding of its offspring, the common cuckoo outsources. When she’s ready to lay an egg, a female Cuculus ...

A study of reed warbler behavior reveals for the first time that in assessing the risks posed by cuckoos the birds combine information from multiple sources. An 'information highway' provides one set ...