The process of deciding which combination of half chromosomes (chromatids) is completely random just like tossing a coin is completely random.
No they don't
For example humans. Technically humans are place below a wild predators such as sharks in trophic levels.
But the fact is we can eat sharks. So , organisms don't always stay in the same level
First deforestation takes away trees which help absorb the carbon in the air and second if you burn the trees you release the carbon in the trees
