Oh-oh! Remember Darwin’s secondary theory for unexplained traits of some animals? No, that’s okay I didn’t remember either. For some unusual traits, like the fancy tails of male peacocks, this particular theory states that sexual selection of traits increases an animal's chance of securing a mate and reproducing. Basically, these fancy traits are used to compete with rivals and are used to attract a potential mate. In a new study however, Tamas Szekely and their colleagues contradict Darwin’s own findings:
In a new study, my colleagues and I have confirmed a link between sexual selection and sex ratios, as Darwin suspected. But surprisingly, our findings suggest Darwin got things the wrong way round. We found that sexual selection is most pronounced not when potential mates are scarce, but when they're abundant – and this means looking again at the selection pressures at play in animal populations that feature uneven sex ratios.
Since Darwin's time, we've learned a lot about uneven sex ratios, which are common in wild animal populations. For instance, in many butterflies and mammals, including humans, the number of adult females exceeds the number of adult males.
This skew is most extreme among marsupials. In Australian antechinus, for instance, all males abruptly die after the mating season, so there are times when no adult males are alive and the entire adult population is made up of pregnant females.
In contrast, many birds parade more males than females in their populations. In some plovers, for example, the males outnumber females by six to one.
Image credit: (Jesse Estes/Getty Images)
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I want to point out that "luck" kicks in for both, the "best suited" and the "worst suited". So i expect that the "lucky factor" evens out in evolution. Similarly the bell curve (if it is present) also evens out between "best suited" and the "worst suited". The walmart experience may be caused by different assumptions: as first i would suggest that "best suited" in view of evolution is not the same as you (or anyone else) would expect as "best suited". In my opinion evolution is driven by selection, especcially by fhe selection which individual is not to pass it's genes. Having this in mind maybe evolution is at least partly switches off in the human civilization (which is ok for me as with my glasses i would presumalby sit on a dead branch)...
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Because animals follow determinism, genetics, luck, etc. -not Darwinian selection. It's also silly to suggest that "the best suited" are the ones thriving at any given time. Next time you go to Walmart, count how many people you see are "the best suited" for breeding. If anything, I would say "the worst suited" are having the most kids, and have been for awhile. And even if you could prove that "the best suited" are breeding, guess what happens when they have kids? The Bell Curve kicks in - meaning if you have 5 kids, 3 will be average, 1 will be above average, and 1 will have learning disabilities. So even if "the best suited" were breeding, they empty back into the world the worst suited. And the cycle continues. People spend too much time fetishizing Darwin and Evolution Theory without actually unpacking the nuances. And I haven't even got into how strong the element of "Luck" plays into breeding/selection/general success as an animal. How many "best suited" animals have ever existed -who ran into Bad Luck- and never bred? If you're not factoring in Luck you're not having a real conversation.
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