How do Natural selection variation and adaptation all play a part in the process of evolution?

Answer 1

All creatures including human being undergo some kind of mutation is just that some mutation are very obvious, some are hidden mutation or some is so minute we dont even bothered as a mutation (eg. albino eyes, tan skin and other random stuffs like that). in normal circumstances, mutation doesnt affects the way we live as our body is already mutated for a certain enviroment but when circumstances changes, those with a better mutation would strive.

Take this example that DID NOT exist: lets say green eyes is one of those random mutations that no one cares about in normal circumstances. lets say in the future, some kind of solar flare hits earth and only those with green eyes would survive the flare. green eyes is at first very rare but as more non-green eyes died, only those with green eyes survives and their population became more. when they mate with other people, some of their childrens might have green eyes and some not. those without have a lower chance of survival. this continues until all human races have green eyes that can adapt to the solar flare.

this is what happen in natural selection. only those with the adaption survives these extreme circumstances. some evolution and mutation occur during this events as their body slowly mutate to adapt the enviroment and only those with a better mutation would survive long enough to pass their traits to their kids. our genetics are not fix and can change (or mutate) with the enviroment. like how some people are genetically born tall but due to lack of nutrients, they became short instead.