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Biology

Mate Guarding and Sperm Competition in Damselflies

Quick fact

In many damselflies, the last male to mate fathers over 90% of the offspring, thanks to specialized structures that physically remove sperm from previous rivals.

Why this is interesting

You might think that after mating, the male's job is done—but in the world of damselflies, the real battle has just begun. Why would a male risk his life to stay glued to his mate?