Social psychologist Darryl Bem theorizes that biology has an indirect influence on sexual preference. Bem believes that biology effects emotions and behavior in young children. Therefore helping influence the individuals sexuality latter on in life. I strongly believe in his idea of developmental sexuality because it supports the idea that the same causal forces drive both heterosexuality, and homosexuality. As well as that heterosexuality does not fragment from homosexuality but that sexual preference is developed by an individual's personal life experience, and biology.
Bems theory of homosexuality is as follows. Children who engage in "abnormal" type of play, for example boys usually play rough, while girls usually play in a less physical way. Young children who usually avoid playing in a stereotypical sort of manner, will overtime develop an altered self image than that of their peers. The child will in turn see himself as different and not a part of the group. The child will eventually disassociate themselves from the rest of their peer group. .
In hetero and homosexuality the individual will associate themselves with the group they feel most comfortable with. The group which who they are dissimilar to with, will tend to be the group that they perceive as emotionally and sexually arousing. Heterosexual males will associate themselves with other males seeing as they have more in common with them. Heterosexual men will disassociate themselves with females and in turn their emotional and erotic feeling towards females will develop over time. The opposite is true for homosexual individuals according to Darryl Bems theory.
Bem states "Exotic becomes erotic." The young child's disassociation will cause them to generate feelings of emotional arousal towards the group it sees as dissimilar to. This feeling of arousal will then eventually develop into a feeling of sexual arousal, subsequently influencing the individuals" sexual orientation.