Urologist Jennifer Berman and family medicine physician and sexologist Rachael Ross joined the series. Psychiatrist and sexologist David Oliver Cauldwell argued that transsexuality was caused by multiple factors. A friendship and working relationship began subsequently with pioneering sexologist Alfred Kinsey. She was married to the early sexologist Havelock Ellis. Sexologist Alfred Kinsey suggested that the buttocks is the primary sexual presentation site in primates. Cohen Greene is a certified Clinical Sexologist and a sex surrogate partner. The term "transvestite" originated in 1910 from the German sexologist Magnus Hirschfeld. Sexologist Magnus Hirschfeld first suggested a distinction based on sexual orientation in 1923. "Reich" is a reference to communist sexologist Wilhelm Reich. Sharon Mitchell is an American sexologist and former pornographic film actor. During this period he took part in the research of sexologist Alfred Kinsey. "Sexplanations" is a video series explaining sexual topics, hosted by clinical sexologist Dr. Lindsey Doe. Rwandan sexologist Vestine Dusabe said that 90% of women experience female ejaculation from kunyaza. Sexologist John Money coined the term "gender role" in 1955. Included in the project was writer and sexologist Carol Queen.