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Human Males Evolve At a Faster Pace Than Females
Tisha_AH writes "A report by the Whitehead Institute indicates that the human Y chromosome present in males is evolving at a furious pace. Across the chromosome there can be as much as a 33% difference within humans alone. The portions of the chromosome evolving fastest are related to sperm production."
Al least some scientific data ;-)
Very seriously, I had a feminist girlfriend that wouldn't believe a child sex was defined by the spermatozoid. According to her the female genitals were as much responsible for the sex of the child.
I guess this article explains everything, she needs more evolution in order to understand those advanced concepts ;-))
Everything I write is lies, read between the lines.
...at what they are looking for in a mate.
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Contrary to a widely held scientific theory that the mammalian Y chromosome is slowly decaying or stagnating, new evidence suggests that in fact the Y is actually evolving quite rapidly through continuous, wholesale renovation.
If I had a nickel for every time I had a nickel, I'd be richcursive!
Right, but the gene distribution present within the population is indicative of the changes in genotype within the population.
The notion of evolving males is not silly. That's why peacocks have big bright displays, while peahens are boring brown. (This is even within the wild population of peacocks.)
This is called "sex selection," and Darwin wrote extensively about it.
Microsoft is to software what Budweiser is to beer.
>The cynical among us might say that we're finally catching up...
Why is shit like this tolerated? If this was said about women then it would be sexist and marked as a troll. But when its about men, its "Interesting." Sadly, making fun of boys and men is standard fare in American society. Every sitcom and commercial has the smart wife and the idiot husband dynamic where the husband cant do something simple but the wife can.
As an adult this doesnt bother me, I just feel sorry for kids growing up today believing this garbage and we wonder why so many of our boys end up as dropouts and criminals. Perhaps society shouldnt be painting them as morons 24/7 and let them develop some self-esteem.
It's not just that, but look at the engineering here...
Testicles sit outside of the body (because sperm can't handle internal body temperatures for too long), so they get exposed to all kinds of fun stuff: radical temperature extremes, physical abuse, etc. Males generate new sperm all the time from scratch, and in huge frickin' numbers. Sperm cells are built to compete and operate at high energy, requiring high sugars just to survive (after all, they're literally shot into the vagina - or in most /.'ers cases, into something else).
Women OTOH have all of their eggs tucked inside, deep in the abdomen, where they stay in a nice, consistent environment. IIRC, they also have all of their eggs present in their body when they are born. Women only drop like one egg a month (excepting twins, fertility drugs, etc), so there's no competition or rush for the egg cell as it drifts slowly down the uterus - either into oblivion or fertilization.
Quo usque tandem abutere, Nimbus, patientia nostra?
Exactly. There are far more lonely men than women and women are lonely often because of their own decision and not because they cannot find anyone. There are also very successful males who have got some kind of a harem. Hugh Hefner is a prime example.
The old joke demonstrates this pretty well:
Boy: I have a dick, and you dun have!
Girl: My mother said, when I grow up, I can have as many as I want
"It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
This has been known for a long time. It is called "male driven evolution". This happens because in humans (and most animals) the cells producing sperms divide about 6 times more than the egg cells. And guess what: studies in a human gene that has a homologue in both X and Y chromosomes, showed that (you guessed it) the Y homologue changes about 6 times faster than the X one.
Did I say old news? 1947 old:
“The primordial oocytes are mostly if not all formed at birth, whereas spermatogonia go on dividing throughout the sexual life of a male. So if mutation is due to faulty copying of genes at a nuclear division, we might expect it to be commoner in males than females.”
“ we should expect higher mutability in the male to be a general property of human and perhaps other vertebrate genes.”
J. B. S. Haldane. 1947. The mutation rate of the gene for haemophilia and its segregation ratios in males and females. Ann. Eugen. 13:262-271.
I don't mind dating a girl that has been with everybody, as long as she had a good shower afterwards.
testicle size in simians is correlated with female permissiveness. such that, in chimpanzees, where a female in estrus is pretty much a gangbang, chimpanzees males have evolved humongous testicles. they need to, because in such a situation, the only strategy available to the male to ensure his genetic continuance is to simply overwhelm other male's sperm with sheer ejaculate volume
meanwhile, in highly monogamous simians who mate for life, such as gibbons, the testicles are tiny. there's simply no need for so much ejaculate volume, its a waste of resources. she's not going anywhere
interestingly enough, human males have intermediate sized testicles, owing to the fact that human females are semi-monogamous/ semi-polygamous
however, i've always wondered why testicles appeared on the outside of the male mammalian body. it seems a ridiculous vulnerability and i've never heard a good explanation as to why. for example, dolphins aren't swimming around with their balls out: the need to be streamlined. of course sperm need a lower temperature to develop, but thats an effect, not a cause. i'm saying wouldn't it be better to have your testicles inside your body and evolve sperm that develop at a higher temperature? its pretty ridiculous to have such an important organ dangling outside unprotected. i never understood why
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
The notion of evolving males is not silly. That's why peacocks have big bright displays, while peahens are boring brown. (This is even within the wild population of peacocks.)
This is called "sex selection," and Darwin wrote extensively about it.
But that doesn't happen independently from the females. In fact, it happens exactly because of the hens. Sexual behaviour is a complex interaction, and the bright displays are only a manifestation of that. It happens because of tastes, roles and behaviours within the entire population, and it's likely that many genes involved in this are carried just as much by the female peacocks, but they only express themselves in the males.
If the Y contained nothing, then males would inherit exactly zero traits from their fathers.
That bit is wrong... fathers provide 23 chromosomes in total, just like mothers. Daughters inherit plenty of traits from their fathers, after all, and they don't have a Y chromosome.
I like basketball!!1!
It may also represent societal pressures on men.
Men have a shorter life expectancy, also indicative of stronger pressure on the males of the species.
For example, if men tend to do more dangerous jobs (soldering, firefighting, etc...) this means the selective process among males is different, possibly harsher.
In other words, this is proof that men have it tougher than women, so my wife should quit her belly-achin' and bring me a sammich!!!
Male-only sexual selection has been seen before. I can't remember the species, but its sperm has become cooperative, not swimming solo like your regular sperm, but hooking up in huge clusters, so they can swim faster than the sperm of the competition. Although that case was related to promiscuity, you could theoretically even get effects like this in monogamous species, although at a far lower pace. Suppose a mutation in one sperm stem-cell makes its y-chromosomes contain some useful trait. Then its offspring might stand a better chance beating other sperm from the same individual even.
God I hate this kind of shit
Why is it so hard to only have politicians for a few years, then have them go away?
Yes, that is true. Historically only 40% of all males were able to produce offspring while over 80% of all females were. Since 60% of all males were evolutionary losers but only 20% of females ofcourse that produces different survival strategies for the genders.
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Mod parent down. The point he made is entirely wrong.
According to the grandparent's hypothesis, genes would mutate more frequently in men than in women. Genes that are shred between the genders would mutate more in men than women, but in each child a mixture of the more-mutated and less-mutated genes would be provided by the two parents and so they would average out. The genes only present in the male (i.e. on the Y chromosome) would not have this averaging effect and so would contain a higher total level of mutation. X chromosomes inherited from the male parent in women would be more likely to be mutated than the ones inherited from the mother. Y chromosomes do not appear in females, so they would only come from the father and would be subject to a greater amount of potential mutation. Multiply this by a few thousand generations, and you'd see a greater level of mutation in the Y chromosome than in the rest of the genome which is exactly what TFA says is seen
The grandparent produced a hypothesis that supported the observation. The next step according to the scientific method is to design a test that would contradict the grandparent's hypothesis but not the observed evidence. Not simply to say 'mod parent down'.
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Possible reasons...
1) Sperm better resists the flood of estrogen chemicals and produces more babies.
2) Random chemicals in the environment are mutating the Y gene faster (so change is not coming from a benefit just a lot of random change)
3) Sperm lasts longer to evade birth control as long as possible.
Male sperm production is down by about 1/20th of what it used to be the last I read so there is a lot of pressure here.
4) Mutated sperm trying to develop laser beams to cut through condoms and diaphrams.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
Evolution is nothing more than mutations over time.
Absolutely untrue. Evolution is mutation plus culling. Without the culling, you do not have evolution. If you put together a situation in which all mutations are likely to survive, then there is no evolution, there is just divergence (this doesn't happen in nature and is very hard to make happen in a lab). Evolution requires some conditions which will make some mutations more able to survive and reproduce than others. In each generation, some mutations will be favourable, some will not. Most will be a mixture of both.
The culling process (starvation from inability to catch prey, death from not being able to outrun predators, inability to attract a mate caused by not having bright enough feathers, and so on) ensures that the mutations that are beneficial are more likely to enter the next generation than the ones that are not. The result of this process over time is evolution. Mutation is just a part of it. You can even have evolution without mutation if you start with a sufficiently varied population. Over time, the population will evolve towards a less varied group with only the characteristics suited to that particular niche.
Further, you can have a few individuals of a group evolve at a different rate and in a different direction than the remainder of the group. Humans are good example of this.
Absolutely. White skin, for example, was a mutation with both advantages and disadvantages. It increased the risk of death from skin cancer, but also made it easier to absorb vitamin D. In regions with lots of sunlight, evolution selects against this mutation because it kills more than it saves (you aren't likely to be short of vitamin D in the middle of Africa, but you are likely to develop skin cancer). In colder climates, vitamin D shortage is a real problem, even in a modern society; there have been a number of well-publicised cases in the north of England recently where black children suffer from a deficiency caused by not receiving enough exposure to sunlight, while skin cancer from exposure to sunlight is much rarer.
Note, however, that both the mutation and the culling are required. An individual that develops white skin has not evolved, it has mutated. A population that develops white skin because it has a greater survival utility in northern Europe has evolved. The same mutation in Africa will be as likely, but is much less likely to be passed on because it does not confer a survival advantage (the reverse, in fact) and so will not contribute to evolution.
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Thankfully I survived the life-threatening aspects of soldering back in my days of playing with electronics.
TV panders to women because TV is all about selling advertising. Advertising is all about selling crap. Who does the day to day shopping? Unless you're a single guy it's probably a woman. For most goods, advertisers value the eyeballs of women far more than those of men. This is why nearly every TV program that isn't a guy's show (sports/fishing/woodworking/etc) must be palatable to women. If women won't like it it's not on TV.
"Liechtenstein is the world's largest producer of sausage casings, potassium storage units, and false teeth."
Evolution doesn't give us the best possible solution, just one which was "good enough" at some point in time. As a result we have spines which hurt, wrists which break easily when we try to protect us from a fall, women who become infertile long before they would lose the strength to carry a child, etc.
By and large, the idea than women earn less for equal work is incorrect these days. Yes, women earn less, but that's because they choose safer jobs on average (over 90% of workplace deaths are men), they are more likely to take extended periods of time away from their careers for child-rearing (in most places in the world, paternity leave is a pittance compared with maternity leave), they aren't as demanding when they ask for raises, they choose more pleasant indoor jobs at a higher rate than men do, they work fewer hours on average (men work more overtime on average and are more likely to be employed full-time), and other things of this nature. Once you control for factors like this - factors that boil down to women being less committed to their careers on average than men (who are viewed as the bread-winner and judged harshly if they can't provide for their families) you'll find that the sexes are about equal. Sure, you might put in equal work to your male peers, but other women who make different choices bring down the average salary for women. It's not discrimination, it's choice that causes women to earn less on average.
Look at it this way: if you really could get the same amount of work from a woman at only 70% the cost, who would ever hire men?