Back in January, Annalee Newitz told me about her idea for an experiment: a site entirely devoted to the science and technology of sex. “Sign me up,” I said. It’s been a ton of fun. And now the experiment’s over.

Anyone who’s been paying attention knows that high school sex education in the United States is an unholy mess. And as a result, an alarming number of students enter college with little knowledge about how their bodies work in terms of reproductive health.

Sperm usually swim in a 3D shimmy: a spiral wave travels down the whippy flagellum and rotates its head in a circle around its long axis. That “bulk swimming” is fine most of the time, but it isn’t a great option when a sperm cell gets close to a surface. That’s when they switch to “slither” mode.

The New York Times is following a team of doctors at the Cleveland Clinic as they attempt the first uterus transplant in the United States. If successful, the procedure will let women who’ve had a hysterectomy, or who were born without a uterus, carry a fetus to term and give birth.

The birds you see above are all ruffs (Philomachus pugnax): wading birds that summer in marshes through Northern Europe and Asia. All three are wearing different forms of breeding plumage. And all of them are male.

Someone please tell me this is a hoax. Announced yesterday with a tweet, the IziVibe claims to be a vibrating dildo you attach to your phone.

People are crap at estimating risk. They’re scared of flying, for example, even though it’s far less likely that their metal sky-bird will crash and burn than their car will get crushed by a truck on the way to the airport. Combine that with a tendency to get judgey about sex, and you’ll find attitudes that can have…

The companies that market so-called “natural” sexual health supplements make a lot of promises, especially when they’re pitching more frequent and harder erections. But do the herbs they put in those pills actually, y’know... work?

Seahorses are famous for flipping the usual reproductive pattern on its head–a seahorse female impregnates the male by laying eggs in his pouch, and the male cares for the developing babies through an 18 day “pregnancy.” But you have to wonder: how does she get her eggs in there?

Puberty has a clear physiological signpost in girls: sooner or later, they have their first period. That’s been a critical part of identifying genes that influence when puberty starts in girls, but it wasn’t clear whether those genes also affected boys the same way.

Male animals can be greedy about paternity. They’ve evolved a ton of different strategies to help them monopolize a female’s eggs. Beating up rivals is a general favorite. Some species use long bouts of sex to keep females away from new mates. Still others stop up female genitals with gooey plugs or bits of broken…

Some people cheat on their partners. Others wouldn’t dream of it–the risk is too huge. A new video from ASAP Science lays out how genetic differences in the neurotransmitters that promote risk-taking and social bonding might influence people’s willingness to stray.

Northeastern University biologist Jonathan Tilly is certain he’s found egg-making stem cells in adult mice. If he’s right, it would refute decades-old work that showed female mammals finish making all their eggs before or shortly after birth. This might make it possible to grow new eggs inside the ovaries of older…

The Bread Lab at Washington State University is a collaboration between plant geneticists and master bakers. The goal? To breed new varieties of wheat that can turn out superior breads and beers while still growing well in the cool and wet Northwest climate.

This short video from the Howletts Wild Animal Park captures the moment an endangered black rhinoceros entered the world last month. It’s the grand finale of a 15 month long gestation.

For the past 25 years, men whose sperm can’t manage the arduous swim across a Petri dish have had the option of injecting a single sperm cell directly into an egg. But that method still left some sterile men out in the cold.

The corals of Australia’s Great Barrier Reef are having their annual orgy. Although some corals brood their eggs in their bodies, or bud off clones, most of the Great Barrier Reef’s corals–140 species worth–release clouds of eggs and sperm into the water en masse.

You know the story of mammalian fertilization: millions of sperm enter the vagina, only one fertilizes the egg, more than one messes up the embryo, yadda yadda yadda. Turns out that’s not the only way it can work.