B00, lefties are of course deviant abnormal's because I am normal and I am right handed. The worlds funny like that, because everything I do, say and believe and any characteristics that I present are normal, its everyone else that aint right!
Christians can believe that the bible inferred 1 woman and 1 man to be mankind in general, so rather than relate a biblical story that contained a million or so men, and a million or so women all shacked up in a small garden (like BB heaven forbid!) , it was far simpler to tell the story in singular form. So in that respect I agree with JTL that sexuality of any variance has been ever-present. Where we disagree, is in everything else.