'Gaydar' Automatic and More Accurate for Women's Faces; Accurate Even When Faces Were Upside Down, Psychologists Find

http://www.sciencedaily.com/releases/2012/05/120516115859.htm

ScienceDaily (May 16, 2012) — After seeing faces for less than a blink of an eye, college students have accuracy greater than mere chance in judging others' sexual orientation. Their "gaydar" persisted even when they saw the photos upside-down, and gay versus straight judgments were more accurate for women's faces than for men's.

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Tabak says that our ability to spontaneously assess sexual orientation based on observation or instinct conflicts with the assertion that if people just kept their sexual orientation to themselves then no one else would know and discrimination wouldn't exist, an argument frequently used by opponents of anti-discrimination policies for lesbian, gay and bisexual people.