Why sex gets cocks crowing

[Indenturedebtor]

01 November 2008
From New Scientist Print Edition. Subscribe and get 4 free issues.

A DAWN cacophony is a cockerel's attempt to safeguard its unborn offspring. Sex, it seems, makes chickens noisier and more likely to raise the alarm if there is a potential threat.

Behavioural ecologists were not sure whether males squawk mainly to attract mates, impressing hens by putting themselves in a situation where predators might notice them, or whether they screech after the event to protect any future offspring.

David Wilson from Macquarie University in Sydney, Australia, and his team kept 30 cocks and hens separate for five weeks and then paired them up in individual enclosures for two weeks. The males' screeches were recorded for 2 hours a day at sunrise - when predators are most active - a week before mating, during the time the pair were together and for a week after.

The frequency of alarm calls went up by 30 per cent when the cocks were allowed to mate (Animal Behaviour, DOI: 10.1016/j.anbehav.2008.08.021). In the week after mating, the cocks still squawked 20 per cent more than before mating occurred. This supports the idea the cocks are willing to put themselves in danger to protect their "investment" or future offspring.


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Interesting, and certainly a nomination for best article title of the year :rockon: