Tuesday, January 10, 2006

Pigmentation and aggression

Richard Macey:

Now two Sydney biologists have found evidence that redheads, in the bird world at least, may have an evolutionary advantage allowing them to rule the pecking order.

They made their discovery after observing hundreds of endangered Gouldian finches, brightly coloured birds from northern Australia that can have red, black or yellow heads.

After breeding hundreds for testing, Sarah Pryke and her University of NSW colleague, Dr Simon Griffith, put a redheaded and a blackheaded bird in a cage to see which one claimed control of the seed bowl. They repeated the test using yellowheads.

The reds controlled the bowl 74 per cent of the time against blacks and 81 per cent of the time against yellows, while blacks frightened off yellowheads 57 per cent of the time.

When redheads were dyed black, they still remained aggressive and retained control of the bowl, but the blacks challenged them more often.

And yellowheads dyed red found the previously tougher blackheads backed off. "It was as if they were saying 'we won't mess with you because you're a redhead'," Dr Pryke said.

She said a possible explanation was that genes for colour may be inherited along with genes that control hormones, including testosterone.

But while redheads ruled the roost, they were very stressed from fighting and died younger.

While reluctant to speculate on whether evolution had given humans with different coloured hair varying levels of dominance, she agreed it was hard not to wonder. "It may be why we associate red with aggression."

I wonder if there are any scientists brave enough to conduct this sort of research in humans?


At 10:31 PM, Anonymous John Russell said...

A little hard to do research when they would chop your funding for a thought crime.

two words; Dmitri Belyaev

At 10:01 PM, Blogger polo shirts said...

History of polo ralph lauren. Polo fashions had its humble beginnings in 1968 when tie salesman Ralph Lauren gave it a kick start. By 1969 he had a boutique polo ralph lauren factory stores within the Manhattan department store Bloomingdale's. ... Brands and luxury standard. Since Ralph Lauren's first brand, Polo Ralph Lauren, was launched, the company has expanded to include a variety of luxury brands such as Polo Golf, Polo Denim, Polo Sport. You can buy cheap Ralph Lauren Clothing at Ralph Lauren outlet.Also We provide polo shirts
Ralph Lauren polo shirt, 50% OFF! polo ralph lauren outlet online is your best choice!In 2006, polo ralph lauren outlet became the first designer in Wimbledon's 133-year history to create official uniforms for the tournament. As part of this year's event, which starts next week, polo ralph lauren sale will introduces the first ... determination to maintain and enhance the values for which our two brands are famous throughout the world. The rugby ralph lauren brand brings to Wimbledon the look of timeless elegance, drawing on our rich history and traditions


Post a Comment

<< Home

View My Stats