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Re: FW: New Fossil Protection Regulations in China



On Mon, Sep 20th, 2010 at 12:59 PM, dale mcinnes <wdm1949@hotmail.com> wrote:

> > From: david.marjanovic@gmx.at
> >
> > Natural selection is something the environment does, not something
> > living beings (or genes) do. They are the passive part.
>  
> WHAAAAAAAT???? I'm not really sure I understand you here. Natural Selection
> is something the environment does. Correct. Living beings are NOT passive and
> certainly DO select those genes that better express phenotypes that are more 
> sexually attractive to name one example [albeit .... indirectly]. 

I believe you've just named the *only* example of living things creating their 
own selective 
pressure. Even then, the reason why any particular species finds something 
attractive or not is 
usually down to the genes they're carrying. Also, many 'attractive' traits are 
indicative of non-
visual fitness, such as health, bodily strength, or hormone levels. Thus some 
genes that cause an 
appreciation for certain types of attractiveness can be beneficial in other 
ways in the long term, 
and are ultimately more likely to become widespread than a gene that makes a 
species find 
debilitating deformaties attractive.

The majority of selective pressures however come from outside of the species. 
Bacteria might be 
able to alter their genes via horizontal transfer, however more complex 
lifeforms are stuck with the 
genetic cards they've been dealt with (unless they get lucky with epigenetic 
traits).

-- 
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Dann Pigdon
Spatial Data Analyst               Australian Dinosaurs
Melbourne, Australia               http://home.alphalink.com.au/~dannj
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