I think the question is really what is the nature of sex? I think the overwhelming consensus on this forum is that sex is just a thing that you do (like doing dishes or playing video games). If that's the case then it really isn't a big deal because sex isn't a big. In that case why have any sexual norms at all? IMO there is a lot more the sex than just being a thing that people do and consequently saying if two adults agree to it must be okay doesn't jive with me.
I doubt the human population will reach a critical mass of incestuous sex fiends, but the cheetah is likely going to extinct because there aren't enough unique individuals to maintain the population. That is so many Cheetahs are related, it's almost statiscally impossible to rescue the population.
I doubt the human population will reach a critical mass of incestuous sex fiends, but the cheetah is likely going to extinct because there aren't enough unique individuals to maintain the population. That is so many Cheetahs are related, it's almost statiscally impossible to rescue the population.