Where should I begin Capt'n?
Are you seriously this clueless?
You see the little numbers in brackets that occur around the text? Click that, and it'll show you the respecting citation
Also if you're too lazy to educate yourself about an issue you shouldn't be arguing about it.
If genetics were responsible for the loveual orientation of a person; everyone would either be (good majority of) heteroloveuals and (very few) biloveuals. Natural selection would be in favor of those who were able to pass on the loveual orientation gene.
However it doesn't work like that. Homoloveuality and Biloveuality has been around since the dawn of mankind and even animals.
One theory I've seen to explain this is that homoloveuality may be a recessive trait, while people with homozygous alleles have some sort of benefit to heteroloveual individuals.
Similar to Sickle cell anemia: You have the disease if you have both recessive versions of the allele, but having homozygous alleles provides some resistance against malaria without the presence of the disease
Also, there's no reason why homos and bis can't have kids, the parts still work, and there are plenty of people who have forced themselves to