title: O brother, where art thou? The fraternal birth-order effect on male sexual orientation.
authors.affiliation: Neuroscience Program and Psychology Department, Michigan State University, East Lansing, MI 48824-1101, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Puts
authors.forename: Cynthia L
authors.initials: CL
authors.lastname: Jordan
authors.forename: S Marc
authors.initials: SM
authors.lastname: Breedlove
mesh_terms: D001722:Birth Order / Q000523:psychology; D005260:Female; D018451:Homosexuality, Male / Q000523:psychology; D006801:Humans; D008297:Male; D011247:Pregnancy; D012725:Sexual Behavior / Q000502:physiology* / Q000523:psychology; D035781:Siblings / Q000523:psychology*; D013739:Testosterone / Q000502:physiology
chemical_list: D013739:Testosterone