Why do men only have one shaft, yet two balls?
In: Biology
Evolution encourages traits that provide a reproductive advantage. Basically if something enables you to leave more kids behind, that trait is more likely to become standard.
Having 2 testicles means more sperm, and even a back-up option if one gets damaged, thus that’s an evolutionarily advantage. Females tend to only have 1 vagina, so a second penis offers not reproductive advantage.
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