Put it on my Tab

We knew that monkeys paid for sex as soon as they learn what money is. But that’s in a lab, a controlled setting, where who knows what kinds of tricks the labcoats used to pervert their monkey minds. Turns out, though, monkeys in the wild don’t need money to develop a “strangers with benefits” relationship. They’ll happily barter for low-level prostitution. Not only that, the exchange can be delayed. They remember who gave what when and how much and how much monkey business it was worth.