"Eunuch Spiders Fight Off Competition"

ABC:

Male spiders castrate themselves so their manhood doesn't weigh them down when they're fighting off competitors, say researchers.

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CREDIT: Qi Qi Lee 

Caption: "Nephilengys malabarensis male and female showing extreme sexual dimorphism where the much smaller male is resting on the female’s abdomen after escaping from female cannibalism via emasculation during copulation. The self-emasculated male palp (red arrow) is lodged in the female’s epigynum."