Dr. Weill makes this subject understandable by including definitions, explanations of theory, and science and the scientific method. She covers anatomy, genetics, body measurements, sensory systems, birth order effects, and maternal behaviors – all of which have been studied recently in relation to sexual orientation. While there is no definitive proof of the cause of sexual orientation, the sheer number of correlations between testosterone and sexual orientation appears to confirm the neurohormonal theory as a major influence. Meanwhile, the most consistent apparent influence on male sexual orientation is birth order, where there is an increasing probability of a gay male within a family as the number of male children increases.
No data are reviewed concerning determination of sexual orientation due to postnatal social environment. Science requires data, complete with peer review and replication of studies and their results. There is no credible scientific data showing postnatal parental, sibling, or societal influence as influencing sexual orientation.
- Dave Parker