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  • Sex is fun, right? But, what if it wasn't? Finding a partner, maintaining a long-term

  • partnership and procreating at the right time is very difficult. Wouldn't it be better to

  • justmake another me?

  • Six years ago, biologists discovered the Mycocepurus smithii, a species of ant which are ALL female;

  • they're asexual. The queen clones herself and if the eggs go unfertilized they'll all

  • hatch female. Bonus, they then have a whole host of awesome new ants! Sexuality is a lot

  • of work, while asexual reproduction is exceedingly efficient (if less fun), and sexual dimorphism,

  • or splitting into a binary sex pair, limits the speciesdoesn't it?

  • Why do we have sex? Aside from the pleasurable feelings associated with sex, lowering of

  • stress, strengthening of romantic bonds and so on and so forthwhy? Those things are

  • evolution's way of GETTING US to HAVE sex. That's not what I mean. You could say, the

  • WHY is easy, we have sex to reproduce; sex equals passing on genes and a promise of success!

  • But that's STILL not what we're asking. Like, why, man? The Smithii doesn't get busy! She's

  • ASEXUAL. She justclones herself. BIOLOGICALLY speaking, WHY sex?

  • The question "why we have sex at all," has plagued scientists for decades. Some basic

  • theories from the 80s assume the genetic variety is beneficial and sex allows us to purge bad

  • DNA. A book in the 90s invented The Red Queen hypothesis, named after the character from

  • "Through the Looking Glass." This describes sexual evolution like a race. We're all evolving

  • to combat other organisms' mutations, and by doing so, we stay in balance. Essentially,

  • as parasites and predators evolve, the hosts and prey evolve to survive them, facilitating

  • reproduction. Of course, having two sexes is pretty inefficient when you look at it

  • this way. If I'm in a race to the death, I don't want to have to find a date for Saturday

  • too! They call it the "cost" of men, because we don't necessarily NEED men, or do we? I'm

  • biased here, but I hope we do.

  • A new study in Nature Genetics claims to have a scientific way to look at thissharing

  • our genetic material makes us stronger and better able to fight disease. Using genetic

  • material from the 1,000 Genomes Project, researchers compared genomes from Africans, Asians, Europeans,

  • Canadians of French descent and found some parts of our DNA are rewritten more often

  • than others, causing hot and cold spots of genetic mutation.

  • When binary species like humans mate, they EACH release genetic material that can allow

  • the building blocks of genes and chromosomes to combine and mutate beneficially. Some mutations

  • help us, while others increase our risk of diseases. The rarely overwritten "coldspots,"

  • it turns out, is where bad mutations survive. Thanks to sex and these mutations, our genetic

  • material "worsens, and then gets better," but eventually, bad DNA is overwritten.

  • According to separate research by the 1,000 Genomes Project, each human offspring has

  • 60 genetic mutations, or about one for every 100 million letters of DNA. Both asexual and

  • sexual organisms mutate, but asexual organism mutations have to be SO GOOD that they overcome

  • the wider population size, fitness, and mutation rate. It's less likely a single mutated clone

  • will succeed in a colony, versus the constant trial-and-error of sexual organism.

  • That doesn't mean sexuality is better, just another means of success. Bacteria aren't

  • the only asexual animals, some reptiles, insects, and fish reproduce without males around; so

  • binary sexuality isn't a hard and fast rule. Some even do BOTH! Sometimes it's a long and

  • seductive one. *bad-ump cik!* Why we have sex at all is still a mystery, but this pulls

  • back the curtain just a little. In the end, asexuality might be faster, but sexuality's

  • DNA lottery has it's benefits too!

  • You're going to comment on this, maybe you already have. Why do you think, BIOLOGICALLY,

  • we're not asexual? Get down there and talk it out.

Sex is fun, right? But, what if it wasn't? Finding a partner, maintaining a long-term

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なぜ私たちはセックスをするのか? (Why Do We Have Sex?)

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    Cheng-Hong Liu に公開 2021 年 01 月 14 日
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