Sexual selection makes males smarter

In a tiny fish species. Oh, haha, did you think we meant in humans?

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At a time of globally falling birthrates, it was depressing to hear that a bloated middle-aged chainsaw-wielding edgelord has allegedly sired his 13^th child.

It’s Idiocracy. Literally:

You may say that Musk’s fortune – totally unaided by his father’s emerald mine – is what secured him his mating opportunities and that sprang directly from his intelligence.

But then there’s the evidence of the past few weeks. And years. The unhinged and incompetent way he has been realising mobster president Trump’s vision of government, on top of, well, some past behaviour (I recommend Origin Story’s three episodes), suggest at the very least there’s something else going on.

And surely, previous children called X Æ A-Xii, Exa Dark Sideræl and Techno Mechanicus must be a red flag.

Fortunately in the world of mosquitofish, the ladies are more discerning.

Scientists from the Australian National University studied Gambusia affinis – tiny freshwater critters that eat mosquito larvae and have been spread around the world as pest control – to test whether the brainier males got luckier. This would add sexual selection to natural selection as a factor in promoting intelligence in a species.

They put the males through various tests such as navigating mazes, detouring around transparent barriers and learning to remember different coloured spots, which earned them rewards.

The fish were then assigned to 11 outdoor ponds where they could compete for females, and the offspring – 2430 of them in two months – were genotyped to see who was their daddy.

To that poor lab tech, “I run paternity tests on mosquitofish” is a surefire pickup line at your next party.

The males who came through the tests more successfully did have more babies, the authors report, or more precisely: “Males with greater inhibitory control and better spatial learning abilities sired significantly more offspring, while males with better initial impulse control sired significantly fewer offspring.”

So not every aspect of intelligence was an advantage, but that did not stop the exuberant spin put on the results by the team.

“Perhaps females recognised and preferred smarter males, or maybe smarter males were better at chasing the females and forcing them to mate, a common, if unpleasant, practice in mosquitofish,” co-author Professor Michael Jennions told media.

Needless to say we prefer to think of the lady fish choosing the nerds over the jocks rather than succumbing to a manipulative mosquitofish pickup artist.

“Our study,” said lead author Dr Ivan Vinogradov, “suggests that intelligence in mosquitofish isn’t only driven by their need to find food or avoid predators, but also by the complex challenges of finding love. This shows that, much like humans, love conquers all.”

OK Doc, I think someone needs a dip in a cold pond.

Send tiny horny story tips to penny@medicalrepublic.com.au.