CH8 SEX 3Cs: courting, copulating and cohabiting Cultural barriers to desseminating information about sexual behavior The remarkable variety of sexual behaviors Copulatory patterns 1. Sexual attraction Most male mammals are attracted by particular female odors, which tend to reflect estrogen levels Estrogen attraction is associated with the release of eggs Female sexual attractiveness peak fertility 2. Appetitive behavior Speciesspecific behaviors that establish, maintain, or promote sexual interaction Proceptive (female): she may approach males, remain close to them, or show alternating approach and retreat behaviors Eg rats exhibit ear wiggling, a hopping and darting gait to induce a male to mount Male appetitive behaviors usually consist of staying near the female, and the male usually stiff around the females face and vagina 3. Consummatory behavior (coitus copulation) Intromission (insertion of penis into the vagina ) stimulation (pelvic thrusting) male ejaculates semen into female refractory phase (period after copulation, which copulation wont recommence) Coolidge effect: males (and to a lesser extent females) exhibit renewed sexual interest if introduced to new receptive sexual partners Heat: estrus = the periods during which female animals are sexually receptive= willing to copulate (coincides with ovulation, conditions are necessary for reproduction) 4. Postcopulatory behaviors Rolling (in the cat), grooming (rat) Extensive parental behaviors to nurture the off springs(humans) Copulatory lock: males penises swell and lock in place for a while, never in humans Maximizes probability of paternity, minimizes copulation by other rival males Eg whiptail lizards, dogs, grasshopper mice Penis captivus: a rare occurrence in intercourse when the muscles in the vagina clamp down on the penis much more firmly than usual (a form of vaginismus), making it impossible for the penis to withdraw from the vagina.