African boobs

I always though those monkey women in central Africa had saggy tits because they don't wear bras but Wikipedia tells me wearing bras makes no difference on saggyness, then why are their tits saggy as shit? And why did tits get bigger this last century in the West? (And Japan too) Howhy?

This may come as a shock for you but as women get older their breasts become saggier... some even start out saggy. And wow omg not all african native women have saggy breasts, look here for example:
http://k43.pbase.com/o6/90/395790/1/70056272.gTI0mxIx._MG_3519a.jpg