Why does sexual selection evolve beautiful features?

Question

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.

Thanks.

Answer 1

I'm not completely certain about the vocabulary used in this context so let me know if you wish clarification

There are a few hypothesis why females care about the sexual features of males, the two most prominent are:

• The sexy son hypothesis states that a sexually attractive male will have sexually attractive offspring which, in turn, is also more likely to mate. This way a female choses to maximize the chance to pass on it's genes to next generations.
• The good genes hypothesis says that males who can afford to develop features that do not benefit their survival but are only for the purpose of sexual selection are healthy, strong and fit. If not, they would not spend resources on sexual attractiveness.

But why are all these features beautiful? Well, the purpose here is that they are beautiful, in terms of attractive, to the recipient of the message: the potential partner. We as humans may find these features also beautiful, as is most likely the case with the colourful feathers of the peafowl. But what about the antlers of deer? Beautiful, dangerous? This is subjective for us ..