Cuckoos are “nest pirates” that lay their eggs in other birds’ nests, setting off an evolutionary arms race that leads to the development of new species ...

Figure 1: Comparisons of Horsfield's bronze-cuckoo and fairy-wren eggs. Figure 2: Kaplan–Meier estimate of the survival functions of Horsfield's bronze-cuckoo chicks, shining bronze-cuckoo ...

Cuckoo chicks are interlopers in the nests of other species, and can be seen being frantically fed by their unwitting foster parent, despite often being clearly many times larger than their hosts.

When disturbed, great spotted cuckoo chicks emit copious amounts of a sticky, smelly substance. The authors tested the novel hypothesis that this stinky substance deters predators from the nest.

Subspecies of the little bronze-cuckoo and the shining bronze-cuckoo track the appearance of their host's chicks across their geographic range. Credit: Naomi Langmore, Hee-Jin Noh, Rose Thorogood ...

A parasitic cuckoo chick foisted upon other birds can turn out to be luck in disguise, saving the nest with a disgusting defense. About 1 percent of bird species, including cuckoos, outsource ...

Cuckoo birds have evolved a nasty habit of laying their eggs in the nests of other bird species, who then unknowingly tend to their young. But as new ...

It’s not all bad for crow chicks who have to share their nest with an uninvited pushy guest such as a cuckoo youngster. For one, they can sit back and wait for food to arrive while the cuckoo ...

This all helps to keep the new parents from catching on to the ruse. And when the cuckoo chicks hatch, they frequently push their foster siblings out of the nest to secure more food for themselves.

These cuckoo chicks are known to emit a foul-smelling fluid from their cloacas. “It is really disgusting,” says Daniela Canestrari of the University of Oviedo in Spain. “It’s pungent ...

If chicks of each host species have a distinct appearance, and hosts reject odd-looking nestlings, then the cuckoo species diverges into separate genetic lineages, each mimicking the chicks of its ...