|
Human cells carry 23 pairs of chromosomes, including one pair which determine gender. [Agencies] |
閱讀難度:
A new study shows that men may not become extinct after all, the BBC reported.
Previous research has suggested the Y sex chromosome is decaying genetically so fast that it will be extinct in five million years. But a new study in Nature suggests the genetic decay has all but ended.
Scientists have now sequenced the Y chromosome of the rhesus monkey, which is separated from humans by 25 million years of evolution. The conclusion from comparative studies is that genetic decay has been minimal, with the human chromosome having lost no further genes in the last six million years, and only one in the last 25 million years.
(點(diǎn)擊BBC網(wǎng)站查看原文)
男人不可能滅絕
???????據(jù)英國廣播公司報(bào)道,最新研究顯示,男人不可能絕跡。
???????之前有學(xué)者稱,Y染色體基因正在快速衰退,可能在500萬年后絕跡。但發(fā)表在《自然》雜志上的論文稱,基因衰退已基本結(jié)束。
???????2500萬年前,獼猴與人類的祖先在進(jìn)化過程中分道揚(yáng)鑣,而科學(xué)家把獼猴的Y染色體基因進(jìn)行排序后,與人類基因進(jìn)行對比,得出結(jié)論:基因衰退微乎其微,在過去600萬年間,人類染色體沒有任何缺少基因,而上溯至2500萬年前,也只缺失了一種基因。
(China.org.cn February 27, 2012) |