Lecture 15: Sexual Behaviour

Question 1

How is sexual behaviour different in domestic animal breeding (farms/zoos) vs in the wild?

Answer 1

Domestic animal breeding: Select male and female pairings to achieve desired combinations of genes in offspring and hope this pair will cooperate by mating (except in cases of AI)

In the Wild: Animals make these choices themselves

Question 2

What is sexual behaviour?

Answer 2

-Importance of mate choice depends on time, energy, and other resources that the animals invest in producing offspring
-Some animals contribute only gametes (inexpensive)
-Some incur much larger reproductive costs (ie pregnancy/nursing = expensive)
-Typically, the sex with the larger investment will be the most selective

Question 3

What are types of mating systems? How do they differ?

Answer 3

-Polygyny
-Promiscuity/polygynandry
-Monogamy
-Polyandry

-How animals gain access to the opposite sex
-Influenced by many factors

Question 4

What is Promiscuity and polygynandry?

Answer 4

Promiscuity
-Animal is largely solitary and mates with whomever they come across

Polygynandry
-Live in groups where everyone mates with everyone

Question 5

What is monogamy?

Answer 5

-1 female and 1 make in a stable relationship

Question 6

What is polygyny?

Answer 6

Polygyny
-1 male and multiple females
-Mostly common in mammals when beneficial for families to form group and then male joins (pride)
-Females can pick the best male with best territory/genes

Question 7

What is polyandry?

Answer 7

Polyandry
-1 female and multiple males
-Doesn’t happen too often
-Reproductive strategy that provides female with different options

Question 8

What are the phases of sexual behaviour?

Answer 8

preparatory behaviours
1. Appetitive phase
2. Consummatory phase (species specific, terminates appetitive phase)

-THe motivational state underlying these behaviours is termed ‘libido’

Question 9

What are preparatory behaviours?

Answer 9

-Changing territories
-Mate searching (Wider/further)
-Male-male aggression (evolution to develop larger body/ features)
-Obtaining resources

(side note some male animals have larger space in brain vs females of same species relate to mate searching need more room for searching remembering map)

Question 10

What is the appetitive phase? How many phases are in this phase?

Answer 10

Often 2 phases within appetitive phase:

-Attraction: emitting stimuli and performing behaviours to attract the opposite sex (tinder bio)
-Proceptive behaviours: promote sexual interaction, adverse readyness to mate (what do on first date)

*both species specific and depend

Question 11

What is the consummatory phase? how many phases are in this phase?

Answer 11

Primarily in species with internal fertilization

-Male intromission (penetration): and ejaculation (typically followed by a refractory period of low sexual motivation)
-Receptive behaviour: by female, typically characteristic stances
-Usually highly reinforcing (reason want successful breeding)

Question 12

What does the consummatory phase look like in males?

Answer 12

-Mounting (clasping with forelimbs and/or jaw)
-Intomission (penetration)
-Refractory period

Question 13

What does the consummatory phase look like in females?

Answer 13

-Receptive behaviours
-‘standing’
-Lordosis
-‘crouching’

Question 14

How does experience relate to breeding in males?

Answer 14

-in general males must learn how to mount and copulate
-Rats need multiple training sessions before they can copulate efficiently
-Roosters too
-Inexperienced dogs show 30% proper mounts, whereas experienced show 97%

Question 15

What are some coastal explanations of breeding behaviours?

Answer 15

Factors necessary to trigger bouts of courtship/mating

Internal factors: the hormones (and neurotransmitters) essential for sexual behaviour

-Males: activational effect of testosterone (varies with species)
-females: estrous and peak estrogen
-Oxytocin and vasopressin- key neurotransmitters in social affiliation/bonding (antagonists can resduce monogyny)

External factors: those affecting general abilities to become sexually motivated (ie effects of season, housing husbandry)
-External cues from potential mate (ie sexual pheromones, visual)
-ex flehmen in horses curl back upper lip, inhales with lip open to facilitate pheromones to expose duct to let pheromones in
-Social group/partner availability - “Coolidge effect” novel inceptive stimuli mostly encouraging so new mate is novel compared to old one so more motivated to mate

Question 16

What are some sexual conclusions?

Answer 16

-Sexual behaviour is a motivated behaviour (with 2 phases)
-Wide variety of mating systems exist with their own implications for mate choice but less control over mate choice in human-managed systems
-Sexual behaviour is influences by a variety of internal and external cues