6 Barbary macaques have a distinctive way to get their mates to make a sperm donation: yelling. If the female does not shout, the male almost never climaxes.

• 北非短尾猿有种奇异的性爱方式：若要让雄性射精，则雌性必须大叫。否则，雄性短尾猿几乎无法达到性高潮。