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Monday, November 23, 2009

Photo: Barnacles Can Change Penis Size and Shape


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A barnacle accustomed to life in relatively quiet waters extends its feeding appendages and its long, thin penis.

A new study shows that barnacles can change the size and shape of their penises to suit their environment. When waters are calm, barnacles have longer genitalia, while those animals living in rough seas make their members shorter and stouter.

Photograph by Chris Neufeld