Sexual behavior

Abstract

Sexual behaviors have evolved to optimize reproduction for a given species. However, in addition to reproduction, individuals also engage in sexual behavior for the associated feelings of euphoria we humans (and most likely all other animals) experience as orgasm. Sexual behaviors include both courtship, such as plumage displays in birds and subtle body language in people, and copulatory behaviors that we commonly think of as sex, including in many animals stereotypical pelvic thrusting, erection, and ejaculation. Such behaviors are produced as a result of a tight coordination between various sensory inputs as well as the internal state of the organism. Of particular importance to the regulation of sexual behavior are the sex hormones testosterone and estradiol, which have evolved an efficient and elegant dual role in many species that both prepares gametes for reproduction and primes the neural circuits underlying sexual behavior. You will find that much of what we know about the brain and sexual behavior comes from studies in nonhuman animals including birds and rodents, and in particular the rat. In addition, fruit fly, mice, and voles have been informative in delineating the genetics of sexual behavior.