With all the interest in duck sex these days, a lecture by the discoverer of gay mallard necrophilia seems timely.
From an evolutionary and biological perspective, animals are driven to have sex in order to procreate. But there is a lot more to sexual relations between animals. Animal sex is at least as strange and varied as human sex. A male might copulate with many females. And female animals of many species can be choosy, too. Homosexuality is common. Monogamy is rare. And the animal kingdom is full of swingers. In short, with animals, sex can be wild.
Unlike many other reptiles, alligators use a penis that is always erect and pops out of their bodies to mate.
Birds and other monogamous animals may continue to make showy mating displays after pairing up because it increases their children's survival.
Nudibranch, a species of mollusk that maintains two sexes at once, use an easily regenerated, disposable penis to have frequent sex
While barnacles have extra-long penises to transfer sperm to other stationary barnacles, they broadcast sperm to reproduce with more distant mates
Compared with their monogamous counterparts, promiscuous mice have developed a much more robust immunity.