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Thursday, October 28, 2010

Photo: Testosterone Gives Male Birds Their Color, Scientists Say


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A new study has found that testosterone increases the level of carotenoids, or color-carrying compounds, in territorial male red-legged partridges (left).

The intensity of a male's coloring (right), along with levels of singing and other behavior, serves as an indicator of his health and sexual appeal.

Images courtesy Carlos Palacin and Julio Blas