Is Homosexuality Genetic?
Is There a "Gay Gene"?
The Importance of Twin Studies
Is There a Link Between Left-Handedness and Homosexuality?
The New Finger-Length Study on Lesbians
How Might Homosexuality Develop? Putting the Pieces Together
The Biological Research on Homosexuality
The Fading "Gay Gene"
Is Sexual Orientation Fixed at Birth?
Can Prenatal Hormone Exposure Influence Gender-Identity Development? -- One Theory