An international team of scientists have stumbled upon an odd yet sensational origin story – the very first act of sex. And, as it turns out, it was committed by fishes with the seemingly apt scientific name of Microbrachius dicki. Now, before the biology expert inside you raises its eyebrows – yes, fishes are known for their spawning, but not reproduction by mating with each other. And that is where the discovery startles us, since this is the first known case of a fish specimen abandoning their usual reproduction methods in favor of what can termed as ‘sex’ (according to this publication from Nature).
The 8-cm long primitive fishes lived inside a lake situated in what is now Scotland, and it was their male specimens that generated the initial buzz in the scientific community. According to Professor John Long (from Australia’s Flinders University), who is the lead author of the published finding, he first noticed something unusual in the male anatomy of Microbrachius dicki, when studying their fossils. This pertained to L-shaped appendages that on further examination were revealed to be the male genitals.
In essence, the males uses these ‘instruments’ (in the form of bony clasp-like projections) to transfer their sperm into the female body. On the other hand, the females received the discharge via their special genital plates that seemingly had very rough textures. Judging from the specimens’ anatomy, the very first act of copulation was performed sideways – thus snatching away the historical credence of the missionary position. Prof. Long has amusingly likened it to a “square-dance style”.
In any case, this method of internal fertilization was not adopted for long, as the fishes reverted to the usual scope of spawning (in which the female releases her eggs and male discharges his sperm in a separate manner, without ‘intercourse’). However, the groovy style of copulation did make a comeback with shark ancestors – but it was a few million years after this venerable ‘first act’.