Class Notes (835,493)
Canada (509,211)
Psychology (7,782)
PSYC23H3 (124)
David Haley (107)
Lecture 4

Reading Lecture 4.docx

2 Pages
Unlock Document

David Haley

Reading Lecture 4: Monogamy and the Prairie Vole (Carter and Getz)  Prairie voles form long lasting pair bonds and both aprents share in raising their young  Oxytocin and vasopressin are important and have roles in reproduction and body water regulation  The chief criterion that defines monogamy is a life long association between a male and a female  Females and males of monogamous species are the same size, defend the net and territory, both care for young, form complex social groups as well including extending fam and offspring of various ages  Monomogy is rare in mammals and commn in birds  Sexual exclusivity is not part of monogamy= proof from DNA fingerprinting  Meadow and montane vole aren’t monogamous  Social cues regulate the reproductive physiology of prairie voles to enter estrus they need to sniff male= male needed to induce estrus have adaptive mechanism to avoid incest  males and females remain prepubescent as long as they stay with their families  Pheromones used= avtivate and trigger hormonal events needed to activate the ovaries and to insuce heat vomeronasal organ regulates and mediates the effects of pheromones, as does the olfac bulb  Once female is exposed to male odors, levels of NE, and LHRH change and LHRH causes pituitary gland to relase LH into blood stream = cascade of chemical and neural events needed to stimulate ovary to secrete gonadal steroids= estradiol (potent kind of estrogen) and progesterone  Estradiol is essential to induce estrus in rodents and only elevates during estrus and declines after mating in voles  In non monogamous rats and voles, progesterone released into blood after mating and helps regulate duration of sexual activity  Prairie voles’s progesterone levels don’t increase until many hours after coitus starts= delay due to prolong mating= 30-40 hrs= lengthy sex= helps sperm enter uterus and enter egg  Prairie voles may copulae to facilitate the formation of monogamous social bonds  Social interaction that follows mating may be one fo the mechanism that reinforces monogamy ina species  Mated monogamous mammals remain highly social toward their mates, even when not reproducing- they touch and remain close to eachother and are aggressive to unfamiliar membrrs of their own sex o Behavior translates into territorial defense and mate defense hormonal events induced by sex might account for the dramatic behavioral changes occurring after mating  Females in their first heat dev a preference for a male if she was allowed to live with him for at least 24 h  Social bonds between mom and kids are associated with release of oxytocin  Oxytocin produced by breast and genital stimulation i.e lactation, birth and mating  Vaginal stimulation or oxytocin treatments speed up formation of mom-infant bonds  Oxtocin would in turn hasten the formation of social bonds between males and females  When injected oxytocin into CNS of females= they became more sociable and is likely to fight with males  When females exposed to oxytocin for 6 hrs they had rapid rpef for males oxytocin receptor blocker eliminated the social effect  Ox receptors scattered in brains diff in distribution in prairie voles in limbic system (sexual and social behavior)  Pair bonding in monogamy also leads mated pairs to guard one another or the shared territory mated prairie voles rarely fight but can be vicious towards strangers  Vasopressin = role in regulating human body water
More Less

Related notes for PSYC23H3

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.