Re: why sex.

On Jun 18, 4:43 am, j...@xxxxxxxxxxxxx (John S. Wilkins) wrote:
Ernest Major <{$t...@xxxxxxxxxxxxxxxxx> wrote:
In message <1j1ib1m.1afg1an18ycddoN%j...@xxxxxxxxxxxxx>, John S. Wilkins
<j...@xxxxxxxxxxxxx> writes
wf3h <w...@xxxxxxxxxxxxxxx> wrote:

On Jun 16, 12:35 pm, Kent Paul Dolan <xanth...@xxxxxxxx> wrote:
The question of _why_ sex evolved seems, perhaps, to
be solved: the deluge of genes migrating from the
newly incorporated mitochondria in eukarytotes into
the cells own DNA (and ever since that first
mitochondria got installed) provided the kind of
intense selective pressure favoring sexual
recombination to cull the losing migration
instancers; though the question of _how_ sex evolved
is still an open issue.

The popularization of the research is here:

http://www.newscientist.com/article/mg20227121.600-has-the-mystery-of...

or

http://preview.tinyurl.com/mqptzq

The images to accompany the text are here:

http://www.newscientist.com/gallery/mg20227121600-attack-of-the-clones

or

http://preview.tinyurl.com/kn85wq

xanthian.

fascinating.  one statement caught my eye:

"Back then, the mitochondria didn't have stunted genomes as they do
today, but normal bacterial chromosomes with several thousand genes.
Martin has shown that, of the eukaryotic genes whose ancestry can be
traced, 75 per cent or more came from bacteria rather than the host
cell."

since we're all eukaryotes, does that mean we're nothing but big
bacteria?

Not really, as Eubacteria is a different group from the eukaryotes. But
in the generic sense, we were all once single celled organisms, yes.

If Cavalier-Smith is correct then we are derived eubacteria. Regardless,
one expects that eukaryotes are derived from bacterial grade organisms,
whether they fall within the bacterial or archaeal crown group or
neither.

Arrgh!! The G word!

Just be glad we have 'words' rather than just assemblages of letters.
Otherwise, you'd be complaining about the G string.

Chris

--
John S. Wilkins, Philosophy, University of Sydneyhttp://evolvingthoughts.net
But al be that he was a philosophre,
Yet hadde he but litel gold in cofre

.

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