"The reason why I don't like drugs: if they are so beneficial, why doesn't the body produce them by itself? It seems to me evolution would have figured out a way to do that by now. If it hasn't, maybe there are some side effects that diminish fitness."
You are forgetting the other side to evolutionary fitness: the environment. Human evolution has been progressively stagnated by the invention of adaptive technology. Being hard of hearing or nearly blind is no longer a deadly condition, hence it no longer prevents procreation, hence evolution doesn't factor anymore.
The human genetic structure is largely the same as it was hundreds if not thousands of years ago precisely because we can use tools to adapt to situations much faster than any evolutionary fitness can proof out and spread through the population.
As for the memory gene of mice, that would only have been important if a better memory made mice more successful at what they do. Evidently in the environments mice adapted to this was not the case.
"Of course evolution might have another "idea" of what is good for us than we do (evolution doesn't really care about us)."
Evolution doesn't have ideas. It does not use reason. It does not think. It exists purely as a pattern of change in species over time. There is no need to give it more credit than that, it is quite powerful enough without the addition of sentience.
You are forgetting the other side to evolutionary fitness: the environment. Human evolution has been progressively stagnated by the invention of adaptive technology. Being hard of hearing or nearly blind is no longer a deadly condition, hence it no longer prevents procreation, hence evolution doesn't factor anymore.
The human genetic structure is largely the same as it was hundreds if not thousands of years ago precisely because we can use tools to adapt to situations much faster than any evolutionary fitness can proof out and spread through the population.
As for the memory gene of mice, that would only have been important if a better memory made mice more successful at what they do. Evidently in the environments mice adapted to this was not the case.
"Of course evolution might have another "idea" of what is good for us than we do (evolution doesn't really care about us)."
Evolution doesn't have ideas. It does not use reason. It does not think. It exists purely as a pattern of change in species over time. There is no need to give it more credit than that, it is quite powerful enough without the addition of sentience.