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The Evolution of Human Sex
22:34 - 24:18 (01:43)
The size of testicles can relate to the promiscuity of females due to the amount of semen they need to wash out, whereas human sex has evolved to encourage pair bonding.
The size of testicles can relate to the promiscuity of females due to the amount of semen they need to wash out, whereas human sex has evolved to encourage pair bonding.