Posted on 01/24/2010 7:05:10 AM PST by TigerLikesRooster
Why the Y chromosome is a hotbed for evolution
Mark Henderson, Science Editor
The Y chromosome is often seen as the rotten corner of the human genome — a place of evolutionary decline that is slowly decaying and threatening the end of man. Reports of its imminent demise, however, have been exaggerated.
Research has indicated that, far from stagnating, the male chromosome is a hotspot of evolution that is changing more quickly than any other part of humanity’s genetic code.
In most mammals the sex of offspring is determined by X and Y chromosomes. Females have two Xs, males have one X and one Y — with the Y making them male. The Y was originally identical to the X, but over 300 million years it has shrunk, and is now the smallest human chromosome.
This is because it occurs on its own, and cannot swap genes to maintain integrity. This decline has led scientists to suggest it would waste away entirely in 125,000 years or so. This would mean the end of men, and probably of humanity.
But the first comparison of the human Y chromosome with its counterpart in chimpanzees has revealed that they differ radically. The findings suggest that the Y chromosomes of both are evolving rapidly and dynamically — probably because of their critical roles in reproduction — and have a vibrant future.
(Excerpt) Read more at timesonline.co.uk ...
*Insert Snarky Comment About Ape-ish Ex-Husband Here*
People are so dense ... predetermined outcome based science isn't working.
Oh Boy,
That Was Close!
Almost Evolved out of Existance! LoL !
How ‘Bout a Big Bang,?
That Would Be Nice !
What A Total Bunch Of Wackos These ‘EVOS’ are.
Oh yeah? Then why did I have a banana with breakfast this morning?
LOL!
This is a lie. There are regions of Y that get swapped with X during meiosis, and Y has to maintain analogous sections with X in order to in order for them to go separate ways during division and only have one per sperm.
God is an EVO.
George: Elaine! Do women know about shrinkage?
Elaine: You mean like laundry?
Jerry: Like when a man goes swimming... afterwards...
Elaine: It shrinks?!
Jerry: Like a frightened turtle.
Elaine: Why does it shrink?
George: It just does.
Elaine: I don’t know how you guys walk around with those things.
Did you bite into it with your incisors or canines?
The author failed biology.
“most mammals” ???????? Name one mammal that doesn’t have males with a “Y”
But , Who Gets The KIDS?
OK, And those Funny Red Hats?
That was DEVO.
What a ridiculous statement. This mechanism for reproduction has been around for hundreds of millions of years, maybe longer--there is no scientific basis whatsoever for hypothesizing that it's on the verge of disappearing. There is very strong selective pressure for maintaining a functional Y chromosome.
Mark Henderson may be the scientific editor for the Times, but he is no biologist.
He would have been correct to say "many vertebrates." In birds, for example, the female carries the Y chromosome.
Incisors, but I had my canines on standby in case it tried to get away ;0)
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