Why Bird Penises Are So Weird

The video explores the vast diversity in bird penis sizes, highlighting the Argentine lake duck's long penis and the seagull's lack of one. It explains how male birds can pass sexual traits to their sons due to larger sex chromosomes, leading to exaggerated traits. Ducks with longer, twistier genitals are more successful in mating, while some birds evolve to have no penises due to mutations. The video also discusses how these mutations can be reversed, as seen in the Chachalaca.

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