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This is scientific American's 60 second science. I'm Christopher Intagata.

Most supermarket eggs look pretty boring.

Plain white chicken eggs, brown ones if you're lucky.

However...

So there's a couple breeds that have blue eggs and you can buy them at Whole Foods,

actually.

Daniel Hanley, an evolutionary ecologist at Long Island University who has a very

specific reason for caring about the color of his eggs.

I'm always thinking about eggs.

It's one of the tools that I used to understand ecological and evolutionary processes.

So I study the function, evolution of natural colors and the main system I use are birds eggs.

Unlike white supermarket eggs, most bird eggs are colored various shades of bluish-green or brown,

due to two characteristic pigments birds produce. And by examining the egg

colors of 634 species from around the world, Hanley and his colleagues found a curious pattern.

In the northern climates where it's the coolest, eggs are darker and browner and those colors should give

some type of adaptive benefit for those parents to be off of their eggs for a slightly longer period of time.

Darker eggs in theory would absorb more of the differently colored duck, quail, and chicken eggs in the sun, they found that the darker

the eggs, the more slowly they lost their heat.

The details and a world map of egg colors are in the journal Nature Ecology and Evolution.

...