And humans don't have the same stunning track record as some of those animals.
"I don't think we are a monogamous animal," Pepper Schwartz, a professor of sociology at the University of Washington in Seattle, told Live Science.
"You get married, and after a period of time, your sexual attraction to your partner seems to wane," Biderman said. I don’t think men ever had an intent to be monogamous." It's unnatural, he insists, and that's why his Web site — which provides a discreet (erm, formerly discreet) outlet for extramarital affairs — is a net positive for the world.
"Monogamy emerged from an economic principle [ownership].  It's true that less than 5 percent of mammals in the world share life-long monogamous bonds.
"A really monogamous animal is a goose – which never mates again even if its mate is killed." So it's clear that humans — who date, sleep around, form polyamorous relationships and polygamous marriages and so on — can't be defined as a monogamous species in the same way a goose can.
But should we be striving towards that goose-y standard? "There are probably good arguments that we’re evolutionarily designed to steal from other people, that we're evolutionarily designed to get into physical fights with people that threaten us, that we're evolutionarily designed to walk around naked," Scott Haltzman, a psychiatrist at Fatima Hospital, told The Post.
Human men have less of an opportunity to sow their wild oats without repercussions, so they may end up with fewer offspring.
But they're able to identify a child as their own, based on the monogamy contract they've bought into, and they're able to invest resources in that child — and in its mother — to be sure any offspring produced will make good on dad's genetic contribution.
 As far as Haltzman (and many in his field) are concerned, the evolutionary history of human sexuality isn't all that important.
At some point, we decided to pair up with one another — and it's a pretty smart reproductive strategy.