To Beat a Parasite, Fairy Wrens Teach Their Young a Secret Password
by Mary Bates
A few years ago, Diane Colombelli-Négrel, Sonia Kleindorfer, and colleagues from Flinders University in Australia discovered a remarkable way one bird fights back against brood parasites, like Cuckoos.
Female superb fairy-wrens teach their embryos a “password” while they’re still in their eggs. Each female’s incubation call contains a unique acoustic element. After they hatch, fairy-wren chicks incorporate this unique element into their begging calls to ask for food. Colombelli-Négrel, Kleindorfer, and colleagues showed that chicks whose begging calls most resembled their mothers’ incubation calls received more food. But the brood parasites of the fairy-wren, Horsfield’s bronze-cuckoos, produced begging calls that did not so closely resemble the parental password.
In a new study, Colombelli-Négrel, Kleindorfer, and colleagues again looked at the relationship between superb fairy-wrens and Horsfield’s bronze-cuckoos to see if a greater threat of brood parasitism would cause the fairy-wren to up its teaching efforts…