Live data from Hacker News

Why Sex? Biologists Find New Explanations

quantamagazine.org

11–20 of 102 posts

Re: Why Sex? Biologists Find New Explanations

#11

Earlier quoted context omitted.

Even acknowledging the basic fact that males have more diverse expression is touchy these days on its own, I find; possibly because people are upset that men and women won't simply be hammered into the same form.

You guys mind backing up your facts? > The simple answer comes down to the fact that a species has to find a balance between maintaining genetic diversity, which is important for resilience and adaptation, and maintaining a strong breeding population. > the basic fact that males have more diverse expression Not to be a jerk, but you guys are just throwing out this stuff without backing it up and it's not at all self-…

The Y chromosome only codes for 55 genes, while the X chromosome codes for 900 genes [1]. The Y chromosome self-evidently doesn't contain genes necessary for basic survival, because females don't have it. Males have only one X chromosome. Each cell in a human female has one X chromosome fully active and another one partially active [2], which means their phenotype, as far at it depends on the X chromosome, has lower variance because of partial averaging.

[1] https://www.genome.gov/about-genomics/fact-sheets/Y-Chromoso...

[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4696107/

Re: Why Sex? Biologists Find New Explanations

#12

Earlier quoted context omitted.

Even acknowledging the basic fact that males have more diverse expression is touchy these days on its own, I find; possibly because people are upset that men and women won't simply be hammered into the same form.

You guys mind backing up your facts? > The simple answer comes down to the fact that a species has to find a balance between maintaining genetic diversity, which is important for resilience and adaptation, and maintaining a strong breeding population. > the basic fact that males have more diverse expression Not to be a jerk, but you guys are just throwing out this stuff without backing it up and it's not at all self-…

Isn't it a common known fact that while average IQ is the same for males and females, male IQ varies more and hence there are more male idiots as well as more male geniuses?

I'm sure you can google the IQ variance stuff.

I'm also willing to bet the height distribution, libido, interest in hobbies, single-mindedness vary a lot more in males than in females.

Politically correctness aside, wouldn't it make perfect sense that the sex that produces more gametes in a day than whole countries of opposite sex in their entire lifetimes would be the sex with more variance in any kind of feature because the potential rewards for taking a genetic risk could also pay a lot more than for the other sex?

Re: Why Sex? Biologists Find New Explanations

#13

Earlier quoted context omitted.

You guys mind backing up your facts? > The simple answer comes down to the fact that a species has to find a balance between maintaining genetic diversity, which is important for resilience and adaptation, and maintaining a strong breeding population. > the basic fact that males have more diverse expression Not to be a jerk, but you guys are just throwing out this stuff without backing it up and it's not at all self-…

The Y chromosome only codes for 55 genes, while the X chromosome codes for 900 genes [1]. The Y chromosome self-evidently doesn't contain genes necessary for basic survival, because females don't have it. Males have only one X chromosome. Each cell in a human female has one X chromosome fully active and another one partially active [2], which means their phenotype, as far at it depends on the X chromosome, has lower…

Colour vision being the classic example of something preserved or enhanced in females due to coding on the X chromosome. This helps women, for the most part, completely avoid red-green colourblindness.

Coincidentally when searching to make sure I wasn't saying this the wrong way around, I was presented with this weird sexist propaganda[0] that only works because of the weird way people tend to think about these facts: you only acknowledge it if you can make it sound like women are better at everything and make no tradeoffs.

[0]: https://www.theguardian.com/books/2020/apr/19/the-better-hal...

Re: Why Sex? Biologists Find New Explanations

#14
post #12

Earlier quoted context omitted.

You guys mind backing up your facts? > The simple answer comes down to the fact that a species has to find a balance between maintaining genetic diversity, which is important for resilience and adaptation, and maintaining a strong breeding population. > the basic fact that males have more diverse expression Not to be a jerk, but you guys are just throwing out this stuff without backing it up and it's not at all self-…

Isn't it a common known fact that while average IQ is the same for males and females, male IQ varies more and hence there are more male idiots as well as more male geniuses? I'm sure you can google the IQ variance stuff. I'm also willing to bet the height distribution, libido, interest in hobbies, single-mindedness vary a lot more in males than in females. Politically correctness aside, wouldn't it make perfect sense…

> Isn't it a common known fact that while average IQ is the same for males and females, male IQ varies more and hence there are more male idiots as well as more male geniuses?

I had heard this as a kid, but I haven’t seen anything to back it up recently that didn’t turn out to be wishful thinking by the author/reposter.

> wouldn't it make perfect sense that the sex that produces more gametes in a day than whole countries of opposite sex in their entire lifetimes would be the sex with more variance in any kind of feature because the potential rewards for taking a genetic risk could also pay a lot more than for the other sex?

I don’t see why the number of gametes is relevant, as the average number of viable offspring is necessarily the same.

Re: Why Sex? Biologists Find New Explanations

#15

The author fails to mention what is probably the largest downside to sex: an entire half of the population is completely unable to reproduce. The question "why do we have sex?" could be restated as "why do males exist?" Unfortunately the answers to that question trouble some people so it's difficult to establish the truth. The simple answer comes down to the fact that a species has to find a balance between maintaini…

I feel you didn’t read the entire article. They study single gender and asexual species for exactly that assumption you made

Re: Why Sex? Biologists Find New Explanations

#17

Earlier quoted context omitted.

You guys mind backing up your facts? > The simple answer comes down to the fact that a species has to find a balance between maintaining genetic diversity, which is important for resilience and adaptation, and maintaining a strong breeding population. > the basic fact that males have more diverse expression Not to be a jerk, but you guys are just throwing out this stuff without backing it up and it's not at all self-…

The Y chromosome only codes for 55 genes, while the X chromosome codes for 900 genes [1]. The Y chromosome self-evidently doesn't contain genes necessary for basic survival, because females don't have it. Males have only one X chromosome. Each cell in a human female has one X chromosome fully active and another one partially active [2], which means their phenotype, as far at it depends on the X chromosome, has lower…

This isn’t about sex chromosomes, we have 1000’s of genes that are sex-biased this means that their expression is dependent on sex.

The level of bias isn’t even solely dependent on the gene in question but on much more complex mechanisms that are frankly not well understood for example in humans testicles and mammary glands have some of the highest levels of sex biased expression in of all tissues. Other tissues like brain, heart and muscles also have variance but to overall lower levels (higher brain tissue expression variance in males for example has been linked to higher likelihood of schizophrenia and other mental conditions).

Overall males it seems that there is a higher variances of sex biased gene expression in various tissues compared to females.

This means that it goes beyond we have a backup X chromosome and gene deactivation escape mechanisms.

Gene expression variance can explain why males might a higher overall variance in traits.

Re: Why Sex? Biologists Find New Explanations

#18
post #14
post #12

Earlier quoted context omitted.

Isn't it a common known fact that while average IQ is the same for males and females, male IQ varies more and hence there are more male idiots as well as more male geniuses? I'm sure you can google the IQ variance stuff. I'm also willing to bet the height distribution, libido, interest in hobbies, single-mindedness vary a lot more in males than in females. Politically correctness aside, wouldn't it make perfect sense…

> Isn't it a common known fact that while average IQ is the same for males and females, male IQ varies more and hence there are more male idiots as well as more male geniuses? I had heard this as a kid, but I haven’t seen anything to back it up recently that didn’t turn out to be wishful thinking by the author/reposter. > wouldn't it make perfect sense that the sex that produces more gametes in a day than whole count…

https://en.wikipedia.org/wiki/Variability_hypothesis#Modern_...

Re: Why Sex? Biologists Find New Explanations

#19
post #18
post #14

Earlier quoted context omitted.

> Isn't it a common known fact that while average IQ is the same for males and females, male IQ varies more and hence there are more male idiots as well as more male geniuses? I had heard this as a kid, but I haven’t seen anything to back it up recently that didn’t turn out to be wishful thinking by the author/reposter. > wouldn't it make perfect sense that the sex that produces more gametes in a day than whole count…

https://en.wikipedia.org/wiki/Variability_hypothesis#Modern_...

> In general, most researchers have failed to find greater variability in either sex in any area that is consistent across cultures and not confounded by social factors.

Re: Why Sex? Biologists Find New Explanations

#20
I like how the article starts but I think it got lost a bit in hypothetical and anecdotes towards the end. Not holding it against the article though. As the article rightly points out, anything involving sex drags in biases as well.

I wonder how convergent evolution [0] fits into this? Maybe one form of reproduction leaves a large niche open for another type of reproduction to fill in.

Could it be that there was sexual reproduction first and asexual reproduction came later? We always assume the other way around. But maybe conditions were initially always stressful and only after conditions improved (I am thinking of conditions on Earth when these single cells organisms were evolving) did asexual reproduction start.

Last question, is meiosis and mitosis the only two way to reproduce? I had never really though about it until now.

[0] https://en.wikipedia.org/wiki/Convergent_evolution

Post reply on HN