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\nExplosive penises and the anatomical prevention of duck rape:<\/b> You may not have known this (most of the Ars staff didn’t), but most birds copulate without the benefit of a penis. One of the primary exceptions to this are, of all creatures, ducks. As it turns out, male and female ducks have elaborate and rapidly evolving genitalia. There appears to be a behavioral habit driving this evolution: duck rape<\/a> or, more properly, forced copulation. It seems that males tend to force themselves on females, and females have been evolving convoluted reproductive passages in order to thwart them.\n<\/p>\n \nThe paper in question here actually capture video of the male erection process, which normally takes place inside the female: “Eversion of the 20 cm muscovy duck penis is explosive, taking an average of 0.36 s, and achieving a maximum velocity of 1.6 m s\u22121<\/sup>.” But the female reproductive tract contains awkward bends and blind alleys that can apparently stop the process cold, allowing the female a degree of control over the father of her offspring, regardless of how aggressive he may be.\n<\/p>\n
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