Sociological studies have found that middle managers tend to be more stressed than either their bosses or their underlings. That phenomenon might well be true of all primates, as macaques display heightened stress levels when they are in the middle of their social hierarchy.
Sex is probably the most popular pastime in the history of life on Earth — which makes it all the more ridiculous that so many of us have such a mealy-mouthed way of talking about it. Take the expression "the birds and the bees," which we use to avoid speaking more explicitly about courtship and sex to our kids.
The phrase "battle of the sexes" applies pretty literally to the Assam macaques of southeastern Asia. During mating season, males become extremely aggressive, and females rely on various tactics to defend themselves... including all having sex at the same time.
Even though they're one of our more distantly related primate cousins, macaque monkeys keep revealing remarkably human-like abilities. First they displayed self-awareness, and now it turns out they can count...but only if they don't get to eat what they're counting.