Arash wrote:
> Wrong, I'm not assuming every trait must benefit reproductive fitness,they
very well could be neutral to it, I am assuming that a trait that has a net
NEGATIVE EFFECT on reproductive fitness should fade out of the population
over time.
>>
Then you don't understand the theory of evolution or basic genetics. A good place to start if you're interesting in getting a handle on this stuff: Gould, Structure of evolutionary theory. You'll see why your common sense argument is baseless.
Miles
^^^^^ CB: I think Arash _does_ express accurate understanding of the theory of natural selection and basic genetics, etc. You don't seem to get the basic concept of differential reproduction or differential fertility.
http://evolution.berkeley.edu/evosite/evo101/IIIENaturalSelection.shtml
Natural Selection
Natural selection is one of the basic mechanisms of evolution, along with mutation, migration, and genetic drift.
Darwin's grand idea of evolution by natural selection 1)> is relatively simple but often misunderstood. To find out how it works, imagine a population of beetles:
1. There is variation in traits.
For example, some beetles are green and some are brown.
Natural Selection Natural selection is one of the basic mechanisms of evolution, along with mutation, migration, and genetic drift.
Darwin's grand idea of evolution by natural selection is relatively simple but often misunderstood. To find out how it works, imagine a population of beetles:
There is variation in traits. For example, some beetles are green and some are brown.
2)There is differential reproduction. Since the environment can't support unlimited population growth, not all individuals get to reproduce to their full potential. In this example, green beetles tend to get eaten by birds and survive to reproduce less often than brown beetles do. ( The shorter survival matters because it means having fewer baby green beetles - CB)
There is heredity. The surviving brown beetles have brown baby beetles because this trait has a genetic basis. ( The significance of the longer survival for natural selection is that there are more brown beetle babies - CB)
End result: The more advantageous trait, brown coloration, which allows the beetle to have more offspring, becomes more common in the population. If this process continues, eventually, all individuals in the population will be brown. ( Brown Power ! - Cbrown)
If you have variation, differential reproduction, and heredity, you will have evolution by natural selection as an outcome. It is as simple as that.