In message , Nick Odell
writes
On Tue, 31 May 2011 20:19:08 +0100, Andy Champ
wrote:

On 30/05/2011 19:28, Tim Streater wrote:

Antibiotics work by getting into the bacterial cell and interfering with
some chemical process within it - e.g. inhibiting the production of some
vital enzyme. Bleach and strong acids physically destroy the bacteria.

It's a bit akin to: cyanide will poison us by interfering with our
metabolism. A bullet does it by destroying some vital organ.


IIRC Penicillin interferes with cell wall construction, and prevents
growth. Ah...

http://en.wikipedia.org/wiki/Penicil...nism_of_action

But why wouldn't we be able to evolve resistance to bullets? Toss
enough airgun pellets about, and we'll likely evolve thicker skins (or
faster reactions!) just the way we evolved sickle cell anaemia (gives
malaria resistance) and cystic fibrosis (Cholera).

And in time we'll become .22 resistant... DU cannon shells might take a
while though.

Where was I hearing all about this, the other day? If it wasn't
'Thinking Allowed' it might have been 'The News Quiz' where generation
after generation of mice have had their tails cut off in the (vain)
hope that it might lead to a specis of tail-less mice. Twas commented
that it was all a waste of mice (and tails) since at least one subset
of the human race has been chopping bits off male babies' bodies for
some 1,200 generations with no sign of it evolving into a natural
feature.

Nick

but that is arse about face, you will only evolve a tai less mouse or
whatever if there is some selection pressure - some benefit, to being
naturally taiiess, and so selecting those genes. Whatt you are
selecting for though is mice that are good at surviving and breeding
with their tais cut off.

The way to do it is to allow only those mice with short tails to breed
--
Chris French