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"Highly Mobile" Testicles Frustrate Effort to Calm Hippos in Captivity

Hippos are blessed with, as lead author Chris Walzer of the University of Veterinary Medicine in Vienna put it, "highly mobile testicles."

Unlike humans, hippos' testicles are not external, nor are they tucked inside the abdomen. Instead they are located inside the inguinal canal, a space in the lower front part of the body. But their exact location in the canal varies widely, sometimes minute by minute. "Hippo testicles are retractable, and can vary in depth by around 40cm, which makes them quite hard to find," Walzer said, adding that there had been in the past several documented efforts that tried and failed to locate them, and at least one paper that declared that it was "not known" where they are.

Be warned! If you click on that link, you are going to be subjected to a drawing of hippo genitals!

I've always said that the location of such a sensitive body part on men is really, really stupid. It's just hanging out there, unprotected! Guys need what hippos got - the "ability to yank them more than a foot further into the body".