Scientists discover why the chicken lost its penis.

Researchers have now unraveled the genetics behind why most male birds don’t have penises, just published in Current Biology. [Ana Herrera et al, Developmental Basis of Phallus Reduction During Bird Evolution] There are almost 10,000 species of birds and only around 3 percent of them have a penis. These include ducks, geese and swans, andContinue reading “Scientists discover why the chicken lost its penis.”