Cuckoo finch fools host with multiple eggs

[cronus]

http://www.bbc.co.uk/nature/24205093

Cuckoo finch fools host with multiple eggs

Cuckoo finches lay multiple eggs in the nests of other birds to make it harder to detect the 'imposters', researchers have found.

The name cuckoo is common to many parasitic bird species that rely upon others to raise their young.

African tawny-flanked prinias are the targets of cuckoo finches in southern Zambia.

Prinias' egg colours vary widely but by laying multiple eggs in a nest, cuckoo finches reduce the risk of rejection.

The results of the study undertaken by researchers from the University of Exeter and the University of Cambridge are published in the journal Nature Communications.

"Many brood parasites [such as cuckoo finches] and hosts are locked in ongoing evolutionary arms races, with parasites evolving attack strategies to get their eggs accepted - such as egg mimicry - and hosts evolving defences - such as egg rejection," explained lead author Dr Martin Stevens from the University of Exeter.

"Our work shows that the cuckoo finch has evolved another novel strategy of attack, whereby it defeats both sensory and cognitive components of host rejection behaviour."

The female African tawny-flanked prinia, a species of warbler, lays eggs in a wide spectrum of colours in an effort to fool cuckoo finches.

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[Tero]

Cool! I want to reincarnate as cuckoo finch female. Or oxpecker.

[mistermack]

Cool! I want to reincarnate as cuckoo finch female. Or oxpecker.

It's a crazy situation for the cuckoo finch, as well as it's victims. If the cuckoo finch loses it's own nesting and rearing instincts, it's entirely reliant on other species from then on. If the population of the host birds were to plummet, the cuckoo finch could go extinct. You would get too many cuckoo finches, looking for too few nests, making a crash the following year even more likely.

It's not what you would call an intelligent design.

[Tero]

Cowbirds infest dozens of species, but i guess with one egg.