If you flaunt it, you've got it: how red-heads top the pecking order

Jan 01, 2006
Gouldian Finches. Copyright Sarah Pryke
Gouldian Finches. Copyright Sarah Pryke

Red-headed finches dominate their black-headed and yellow-headed peers by physical aggression and by the mere fact of being red-headed, according to research published in the Proceedings of the Royal Society.

University of New South Wales biologists made the discovery following experiments with stunningly colourful Gouldian finches (Erythrura gouldiae). Among Australia's most endangered native birds, Gouldian finches are now restricted to small isolated populations across the tropical north.

The bird has a bright green upper body, blue rump, violet-purple chest, yellow breast and bright azure-blue collar. But its most distinctive feature is its head, which occurs in one of three discrete colours: red, yellow or black. This colour polymorphism makes the Gouldian finch unique, with three distinct forms all naturally occurring and inter-breeding in the same wild populations.

The scientist's first experiment aimed to reveal if there were behavioural differences between birds that related to the three head colours.

Observing contests between two unfamiliar males over access to food, they found that red-headed males were more aggressive and dominant than black-headed males, while both red and black-headed males dominated yellow-headed males.

In their second experiment, the scientists experimentally changed the head colours of the birds by dying them red or black to discover whether head colour was a communication "signal" between birds.

"Birds were reluctant to compete with opponents that had red dyed heads, demonstrating that they pay attention to this signal of dominance and use it to avoid getting into fights," says one of the study's authors, Dr Sarah Pryke, a Research Fellow in the School of Biological, Earth and Environmental Sciences.

"Red-headed birds that were temporarily dyed were still the most aggressive. This shows that red-heads are truly very aggressive and that it pays black- and yellow-headed birds to avoid fights with them.

"These findings suggest that red-heads have a dominance advantage and will out-compete the other two in contests over limited resources like food and the best nesting sites.

"As well, they show how the expression of a discrete colour is linked to a behavioural trait, and give us a new insight into how colour signals evolve as a form of communication in animals."

Source: University of New South Wales

Explore further: A two generation lens: Current state policies fail to support families with young children

add to favorites email to friend print save as pdf

Related Stories

New species discoveries in the Greater Mekong

Jun 05, 2014

A giant flying squirrel, a skydiving gecko, a fish that mates head-to-head, and an eyeless cave-dwelling spider are among the 367 new species revealed by scientists in the Greater Mekong region in 2012-2013, ...

Sperm cells compete in a never-ending race

May 12, 2014

Researchers at the Natural History Museum at University of Oslo, Norway, were among the first in the world to start analysing sperm cells to learn more about bird evolution and behaviour.

Recommended for you

New hadrosaur noses into spotlight

Sep 19, 2014

Call it the Jimmy Durante of dinosaurs – a newly discovered hadrosaur with a truly distinctive nasal profile. The new dinosaur, named Rhinorex condrupus by paleontologists from North Carolina State Univer ...

Scholar tracks the changing world of gay sexuality

Sep 19, 2014

With same-sex marriage now legalized in 19 states and laws making it impossible to ban homosexuals from serving in the military, gay, lesbian and bisexual people are now enjoying more freedoms and rights than ever before.

User comments : 0