Re: question about evolution

On 2012-02-01 19:32, Ernest Major wrote:
In message<4fydnXE5xeaOTLTS4p2dnAA@xxxxxxxxxxxx>, Friar Broccoli
<eliasrk@xxxxxxxxx> writes
On 2012-02-01 16:00, Paul Ciszek wrote:

Your reply was (in my opinion) the best one so far, for the purpose of
providing the OP with a usable information, with which to reply.

However, I have a completely unrelated question:

Short version: Evolution doesn't work on individuals, it works on an
entire breeding population.

The above statement, which I see frequently here, has always confused
me a bit, however my confusion was heightened recently when I focused
on: Natural Selection occurs exclusively at the level of the individual.

To say that natural selection occurs exclusively at the level of the
individual isn't quite true. There are circumstances in which it can act
on vehicles other than individuals.

For fun I will just make up an explanation:

Speciation is a byproduct of NS acting on natural variation, so the
"evolution" that works on "entire breeding populations" is speciation.

But I know that's wrong because we can have extensive morphological
(and other) modifications over time, without having any speciation.

So how is the logical link made to "evolution works on populations"
from "NS works on individuals, not groups"?

.

Evolution is a change in a population. One of the ways this occurs is
through the differential reproductive success of individuals. When this
is correlated with genotype we label it natural selection. (When it is
uncorrelated with genotype we label it genetic drift.) There are other
evolutionary processes.

This: "Evolution is a change in a population" seems a bit like (well no, exactly like) assuming your conclusion. Can you explain why evolution needs to be defined as a "change in a population"?

Also, thanks for taking the time to try and clear this problem up for me.


--
Friar Broccoli (Robert Keith Elias), Quebec Canada
I consider ALL arguments in support of my views

.

Relevant Pages

  • Re: question about evolution
    ... To say that natural selection occurs exclusively at the level of the ... Speciation is a byproduct of NS acting on natural variation, ... this is correlated with genotype we label it natural selection. ... "Evolution is a change in a population" seems a bit like (well ...
    (talk.origins)
  • Re: question about evolution
    ... The above statement, which I see frequently here, has always confused me a bit, however my confusion was heightened recently when I focused on: Natural Selection occurs exclusively at the level of the individual. ... So how is the logical link made to "evolution works on populations" from "NS works on individuals, ... When this is correlated with genotype we label it natural selection. ...
    (talk.origins)
  • Re: question about evolution
    ... entire breeding population. ... is correlated with genotype we label it natural selection. ... "Evolution can NOT work on an individual..." ...
    (talk.origins)
  • Re: Natural selection and favorable traits how were they measured
    ... beef is not with the label 'evolution' or 'NS' is what actual ... mechanism these terms are supposed to be a proxy for. ... What is natural selection and who says so? ...
    (talk.origins)
  • Re: Darwins principle of divergence - Tautology
    ... DARWIN'S GREAT TAUTOLOGY ... DISCUSSION OF TWO FATAL DEFECTS IN HIS THEORY OF EVOLUTION ... explanation for the diversity of living things in the universe ... The mechanism he referred to was "natural selection". ...
    (talk.origins)