Both left handedness and having older brothers have been seen to correlate with male homosexuality. A forthcoming study reanalyzes previous studies to see if these are mutually existing or competing correlations.
Ex-gay Watch friend, Jim Burroway,comments brilliantly on the study. Go read his comments here. Interesting observations were:
1. Right-handed gay men were much more likely to have more older brothers and fewer older sisters than the general population.
2. Left-handed gay men were the opposite. They were much more likely to have fewer older brothers and more older sisters than the general population. Gay lefties were also more likely to have older siblings regardless of gender than anyone else, included gay men who are right handed.
While these are interesting observations, they are clearly only part of the picture. And this study, like so many others, has flaws and findings that are inconsistent with other studies.
But I can agree with Jim’s conclusion
If we are ever able to tease out all of the possible factors that influence sexuality, we will probably learn that there are many different “types” of homosexuality. For some, it may be genetic. For others, maybe their later birth order after a string of brothers. For others still, it may be the same thing that made them left-handed. For others, their left-handedness may be a red herring and the real cause was their distant father. And for others, maybe their absent father had nothing to do with it; prenatal hormones made it inevitable. And for most — maybe all — it is more likely to be the unique combination of any and all of these factors (and others that we haven’t discovered yet) which forms the basis for who we are.