When it comes to sex, first times are not known for being glamorous. Whether it's your first time with a new partner or your first time ever, the reality is often far from the candlelit, rose-petal-strewn ideal. But, at least you and your partner aren't forced to do it side-by-side. In a lake. With genitals "like cheese graters."
These are the conditions under which the world's first sexual intercourse occurred, according to a team of researchers out of Australia's Flinders University. The BBC reported on the team's latest study (published in the journal Nature), which identifies the origins of copulation. The first organisms to have sex on Earth were the primitive fish called Microbrachius dicki, which lived and mated circa 385 million years ago in the lakes (or rather, the lochs) of what is now Scotland. While examining fossils of these fishes, lead author Professor John Long, PhD, noticed that the males had "large bony claspers" that looked suspiciously like, well, penis prototypes.
Upon further examination, it was deduced that the small, bony structures evident on female fish would have been ideal for locking the male's "claspers" in place, while both fishes' small arms held them together for side-by-side intercourse. "The little arms are very useful to link the male and female together," Professor Long explained to the BBC, "so the male can get this large, L-shaped sexual organ into position to dock with the female's genital plates, which are very rough, like cheese graters."
Apparently, this form of reproduction wasn't very popular, because as fish evolved, they returned to spawning (females release eggs, males release sperm, and egg and sperm meet in the water, no awkward grating required). Millions of years later, sex made a comeback — among the predecessors of sharks and rays — and thankfully continued to evolve from there. Intercourse has come a very long way, kids.