Evolution and gene flow

[student12]

Evolution is the change in genetic material over time within a population. I know that natural selection, and genetic drift can lead to evolution. But does it also include gene flow?
Basically anything that alters a gene pool leads to evolution? eg:mutations

[weesper]

Yeah gene flow can lead to genetic change and thereby evolution, but not 'everything' that alters the gene pool must lead to evolution.

[student12]

can you please give examples that alter gene pool but not result in evolution?

[saizs79]

examples:
1 - synonymous (or silent) substitutions: changes in DNA which do not change the amino acid coded, due to the degeneracy of the genetic code.
2 - Changes in non-coding, non regulatory sequences of DNA: this likely makes up the majority of eukaryotic DNA. It can be changed very much without any change in the fitness of an organism.
3 - Fatal mutations - if an organism gains a mutation that is fatal to it before it can breed it is not heritable. If it's not heritable its not evolution.