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Wikipedia
The Y chromosome is one of the sex-determining chromosomes in humans and most other mammals. In mammals, it contains the gene SRY, which triggers testis development, thus determining maleness.
Overview
Most mammals have one pair of sex chromosomes...
http://en.wikipedia.org/wiki/Y_chromosome
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Links
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Blogs
http://uk.blog.360.yahoo.com/blog-6rf_O.k5erUv2CRwuuTLMwkXng--?cqu003d1u0026pu003d295Entry for 18 July 2008 -- the One with Wracked Nerves (by: unknown)
No offence to anyone who owns a 'Y' chromosome, but oh my giddy aunt. There's always that stereotype about women being terrible navigators/map-readers, etc, but guys... they are something else and not necessarily in a good way. ...
http://browsekid.wordpress.com/2008/07/16/about-me/About me (by: Sidhu)
Is evolution not a resounding proof of the absence of any religious origins or the distinctions that we follow today? Science has the proof, one thing that cannot be changed is that part of the DNA (male chromosome or ‘Y’ chromosome) ...
http://enterload.blogspot.com/2008/07/rieg.htmlrieg (by: utm)
Fortunately, recent results have shown that zebrafish and humans share large chromosome segments which have been conserved intact during the 420 million years of evolution since the divergence of the two phylogenetic lineages. ...
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Videos
Sexual Evolution: From X to Y
tbn257.ram
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Downloads
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Definition
No definitions found for y chromosome evolution.
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Questions & Answers
What's happeneing to the Y Chromosome (evolution question)?
Someone said the Y chromosomes are unraveling which could affect evolution or something, that there'll be less males, or that we're becoming androgenous?
What?
It is possible that the Y chromosome is shortening.
It only contains genes to do with becoming male - genes which the female doesn't need. So losing the Y chromosome would not make females androgynous.
Individuals born currently with 1 X but no Y ("monosomy X") have Turner Syndrome, and are infertile females.
If we suddenly lost the Y chromosome, then no more males would be born, and the human race would have a pretty short lifespan after that.
But - this will not happen due to evolution: in fact, evolution will keep the Y chromosome around. Any population where it disappeared would become extinct pretty quickly, while those retaining it would continue to breed.
A couple of things:
the XY sex determination system is ont the only way of determining gender. Many organisms use different methods: some use different chromosomes (like ZW, used in birds), some use the nutrients fed to the mother, and some even use the temperature the eggs are incubated at.
http://en.wikipedia.org/wiki/Sex-determination_system
if the (very few) genes on the Y chromosome got transferred to other chromosomes, but controlled in such a way as they were only turned "on" when only 1 X chromosome was present, then we could lose the Y chromosome without any problems. Females would still be XX, but males would be XO. This system is actually already used by some insects.
Is there something wrong with the Y chromosome or something?
I was just going thru the discovered questions when I discovered this answer:: "Geneticists have found that the Y chromosome is unraveling. SO it seems that the next evolutionary step will be the elimination of males. it also seems t hat we are becoming more androgynous."
Is this a possible step in human evolution?
I'm so confused.
More pseudo science by alarmists... the human Y chromosome is much more stable than the X chromosome & even uses an error correction code that tends to repair itself. Therefore this is among the most stable of all human chromosomes.
I'll get back with some links.
http://www.sciencedaily.com/releases/2005/09/050906075204.htm
what are human Y chromosomes in evolution?
@qaa_question
I think you will find this article interesting. There was a typo in the title; it is about the shrinkage of the Y chromosome over evolution, but was titled "Disappearing X"
Saturday 8 November 2003
Summary
Imagine a world without men. It's entirely possible. According to Professor Brian Sykes, the Y chromosome, which determines maleness, will disappear in 100,000 to 200,000 years - not long, on an evolutionary scale. And, is it possible that men with the same surname could have identical Y chromosomes?
http://www.abc.net.au/rn/science/ss/stories/s977072.htm
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eg:
"Bryan Sykes: There’s no doubt that the Y chromosome over many millions of years has been deteriorating, it has lost most of its genes, and that’s for two reasons really. The first is that once the Y chromosome decided sex then it became isolated from its former partner, the X chromosome, and all the other chromosomes really, and was no longer able to take part in sexual recombination ironically, since it decides sex. And that isolation has meant that it’s very bad at repairing any mutations, it doesn’t have any reference points with which to compare and mend mutations that occur on the Y chromosome – so that’s one thing. The second thing, that unlike all the other chromosomes, the Y chromosome is restricted every generation, it spends all its time in the testes and that is a very dangerous place for DNA to be. The very high levels of free radicals and other damaging events, there’s a high rate of duplication of DNA, duplication and cell division, and so the Y chromosome alone is restricted in every generation to this hotbed of mutation and it also can’t repair itself. So those two things together have made it deteriorate to such that there are only 27 genes left.
Now, what will happen in the future? Well, I think it’s inevitable and a lot of other geneticists would agree with me, that it will eventually disappear, but the question is, when? ..."
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BTW, if surname matches Y chromosome that well, I suspect that there was not as much marital infidelity as is sometimes said to occur. After all, it takes just one such lapse (that results in a son), in a long line of descendants, and that Y chromosome is shifted to a different surname, in subsequent generations.
Anyhow, mapping the Y leads back to our last common male ancestor, in a similar way to mapping the mitochondrial DNA leads back to our last common female ancestor. This sometimes leads to interesting discoveries eg that male adventurers might have collected females from other populations, en route to colonising new territory, as is thought to have happened in the past history of Maoris in New Zealand:
1. News in Science - Maori men and women from different homelands - 27/03/2003
Summary: ... A New Zealand Warrior and his Wife an engraving from the journal of Captain James Cook's ... s 1784 visit on Endeavour Pic: State Library of NSW
The male and female ancestors of today s Maori people of New Zealand originated from different parts of the world, molecular biologists ... Whyte has now identified 10 haplotypes in New Zealand Maori. ...
http://www.abc.net.au/science/news/stories/s817069.htm - 24k - [ html ] - Cached - 27 Mar 2003
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