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are males going extinct?

baggie

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this may have been discussed before as it is about a month old. Bryan Sykes http://www.guardian.co.uk/medicine/story/0,11381,1030595,00.html thinks the Y chromosome (and presumeably the human race) is going extinct in 100,000 years or so due to Y chromosomal damage. This will be manifest by increasing male infertility. However I have several questions

1. Presumably this must be happening to some extent in all organisms that use Y chromosomes if true
2. Surely this is self correcting. The badly damaged Y chromosomes do not pass themselves on, leaving the field free for us supervirile studs with good Y chromosomes. The net effect is neutral

any geneticists/ mol biols out there?
 
Seems to me that the bad Y chromosome could never survive. All the good ones would just have more children, right?
 
This is just sillyness, where have all the males been for the millions and millions of years that the Y-chromosone has existed.

Woowooowooowooowooowooo
 
I suspect he is saying that the rate of chromosomal drift of damage is so great that it cannot be corrected by normal evolutionary pressure. I presume he knows what he is talking about being a molecular biologist from oxford university. I know that Steve Jones (In the Descent of Man) has also said similar dire things about the Y chromosome, except he estimates about 1 million years for extinction. As he is a prof of genetic in UC, London perhaps we should be worried?

I still suspect that evolution will save the day
 
I remember reading some 70s feminist literature that said the Y chromosome was just a damaged X chromosome. It's weak and flawed thing that should never have happened. Now people are saying it's going extinct.

I find it amusing that the means that most life on the planet uses for reproduction would be inherently flawed and doomed to failure.

It's like someday the planet will be barren of all sexually reproducing life forms, and mother earth with say, "Oops, my bad. Sorry for letting you think you were a viable life form for all those millions of years." :)
 
uneasy said:

It's like someday the planet will be barren of all sexually reproducing life forms, and mother earth with say, "Oops, my bad. Sorry for letting you think you were a viable life form for all those millions of years." :)
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she played that trick on the dinosaurs already, so why not us?
 
I suppose that with cloning and reproductive medicine, we´re almost to the point that women no longer need us, except to take out the trash.
 
I remember reading some 70s feminist literature that said the Y chromosome was just a damaged X chromosome.
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Ha.

The X chromosome is just a fat Y chromosome.
 
Chaos said:
I suppose that with cloning and reproductive medicine, we´re almost to the point that women no longer need us, except to take out the trash.
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It's worth noting that the opposite is also true. Artificial wombs and all that.
 
c0rbin said:


Ha.

The X chromosome is just a fat Y chromosome.
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{feminazi} WHY YOU!!!{/feminazi}

LOL!! Bah, The Y chromosome has been around as long as the X chromosome, and that's before humanity. It's obviously essential and if males go extinct, so will females. Artificial wombs are dang costly....yes, they are! Most females contribute to the household incomes nowadays.:p


Look at Fragile X syndrome and the role that Y chromosome plays in its expression, then tell me that the Y chromosome would be the reason for extinction in a 100 000 years. There are just as many, if not more, faulty x chromosomes out there. Heck, there are faulty chromosomes period, never mind Y vs X.


I also don't feel that men are genetically modified females just because the fetus starts out in the 'female default' model. Starting out with a YX instead of an XX makes men different from the get go. Heck, there are females who feel they should have been male for gosh sakes.

I have no respect for the Guardian.

Sexual reproduction is not limited to mammals either:


But its fate was sealed when it took on the mantle of creating males. This probably happened in the early ancestors of mammals, perhaps 100m years ago when a mutation on the ancestor of the Y-chromosome suddenly, and quite by chance, enabled it to switch on the embryonic pathway to male development. Once this happened, the chromosome was doomed. It slowly lost contact with other chromosomes, thus missing out on the interaction that normally allows the shuffling of genes and so unable to properly heal the wounds inflicted by mutations. One by one, its thousands of useful genes were lost until now only 27 remain - and they are under constant threat.
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:rolleyes: Whatever.

Even haemophilia (sp?) is caused by a mutation due to the X chromosome.
Hardly any genetic diseases are due to a Y chromosome defect. It's a lack of an 'undefect' X chromosome due the Y chromosome presence that allows for the expression of the disease. It's not 'caused' by the Y chromosome though. If the Y chromosome is such a mutant filled anomally, then why are the X chromosomes the cause of most genetic defects?

No, I don't know if the study is completely flawed, but it sounds ridiculous IMO.
 
But its fate was sealed when it took on the mantle of creating males. This probably happened in the early ancestors of mammals, perhaps 100m years ago when a mutation on the ancestor of the Y-chromosome suddenly, and quite by chance, enabled it to switch on the embryonic pathway to male development.
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Uh, sorry, but it's not just mammals which have males. Fish, birds, amphibians, reptiles and many plants do too, so either the good doctor was completely misunderstood, or he is off his rocker.
 
Um...

Doesn't the Y chromosome have relatively little genetic material for a chromosome? And how does this work again? Damaged chromosomes just eventually blip out of existence? I don't get it ...
 
It's like reading an article about the paranormal. He has come to a bunch of strange conclusions, but doesn't mention at all how he reached them, or what research he has done. I don't buy this one bit. He wants to sell alot of books, so of course he writes about mankind being doomed, and makes it sound like sincere scientific research. Seems more like pseudoscience to me.
 
Reptiles manage to have different sexes without X and Y chromosomes. The sex of a crocodile, for instance, is determined by the temperature of the nest. If the nest is too warm all the eggs will be male. If it is too cold, all will be female. If it is just right, it will produce both males and females.

Fish can actually change sex. Experiments have been conducted with fish wherein the males were removed from a group of fish. Some of the females changed into males.

Birds have sex chromosomes called Z and W. Males have 2 copies of the Z. Females have a Z and a W. So the bird strategy is just opposite of the mammal strategy.

The point is that there are a lot more ways to have sexes than just the X/Y method. Even if the Y chromosome dies out, it doesn’t mean that males will cease to exist. Having two sexes appears to be a very useful adaptation and evolution tends to favor it.

As far as the danger to the remaining genes on the human Y chromosome, I think this is rather dubious. While the chromosomes for any individual male may be at risk due to mutation, the chromosomes for the species as a whole are probably quite secure. Evolution involves populations, not individuals.

LOL!! Bah, The Y chromosome has been around as long as the X chromosome, and that's before humanity. It's obviously essential and if males go extinct, so will females. Artificial wombs are dang costly....yes, they are!
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As long as females are around, the extinction of males would not require artificial wombs. The real question is: can an egg be fertilized with the genetic material from another egg? I would think that with current cloning technology, it would be possible to create an animal with two mothers and no father. Has this ever been attempted (I’m thinking mice here, not people)?

If this sort of thing can be done, then we males would truly be redundant. Especially if someone came up with a robot that could empty the trash and open jars (Robo Husband tm). :)
 
Thing is, humans need the testosterone production to become male. This doesn't happen with X chromosomes.

We need the Y to get the testosterone. How would humans be able to get both female and males from 2 X chromosomes?

Crocs have a change due to temp, which is not unusual when considering they are cold blooded. Fish don't have to go far to release sperm instead of eggs. Humans are far more 'complex' in that we need not only the 'switch' in the womb to get males, but continued production of testosterone throughout their lives to get viable sperm.

Artificial insemination is expensive and not as successful as the usual method of insemination. Far as I know, sperm cells don't replicate, so you'd need one heck of a mechanism to manufacture sperm.

Making embryos with only female chromosomes won't get you a male. You'd have to keep men around to put their dna into an egg through cloning. Humans also depend on diversity for survival, which cloning doesn't allow.

I'd like more proof on the Y chromosome being doomed to extinction in only 100 000 years.

How does the author know that evolution doesn't yet have a trick up its sleeve to save the Y chromosome?

I'd love to see more complete information on this 'theory'.
 
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