Love

Question 1

Rareness of Monogamy

Answer 1

• 90% of birds
• 3% of mammals
• 27% of primates

Question 2

Cost and Benefits of Monogamy

Answer 2

benefit: co-parenting increases odds of offspring survival, female protection

cost: decreased opportunity to spread genetic material, challenges of mate-guarding

Question 3

Reasons for Monogamy in Primates

Answer 3

• possibly for biparental care
• mate-guarding in males that increases confidence in offspring paternity
• risk of infanticide

Question 4

Human Design for Monogamy

Answer 4

Testes Size: in primates there is increased sperm competition therefore men adapt

Evolutionary Adaptations:
- penis as a sperm displacement device
- increased sperm count in couples that spend less time together

Question 5

Clues for Male Monogamy from Sexual Dimorphism

Answer 5

• fertile all the time
• in monogamous species males and females are more physically similar
• decreased competition between males for mates lessens the need for competitive features

Question 6

pair-living

Answer 6

two adults and non-reproductive offspring sharing a home range, still with extra-pair mating

Question 7

pair-bonding

Answer 7

long-term social relationship between two individuals

Question 8

monogamy

Answer 8

mating and breeding system with sexual exclusivity

Question 9

Prairie Voles and the Monogamous Brain

Answer 9

• higher release of oxytocin and vasopressin during mating, regulating pleasure centre of female brain, associating happy experience with vole they are with
• compared to Montane vole that show less activation of these hormones during sexual activity