First question here. I have a very raw understanding of sexual selection:
Say a group of females of a certain species "likes" some feature of a certain groups of males; by "like" I mean some behaviour that makes this group of females tend to mate with males having this feature, then the females are selecting their genes which make them feel appealed to males with the feature, and then this process becomes exponent since the group of females becomes bigger and forces the population of males to have this feauture, until an equilibrium is reached. Althought I know this also happens with the roles interchanged.
My first question is, why females tend to like males that have high amounts of these features, more than the average in the population?
My second question is, why the end products of these selections are such beautiful features? Perhaps this may sound a little arrogant but I don't understand how an animal can appreciate this beauty, I suppose this is to make some sort of selection of healthy males.