Male and Female

Question 1

Value of Size

Answer 1

1. advertisement
2. female stimulation

• for short-term relationships females selected bigger sizes as opposed to smaller sizes for long-term relationships

function
- sperm delivery
- sperm removal

Question 2

Primate Sperm Competiton

Answer 2

• relationships between body weight and testes
• comparing chimpanzees (polyamory) and gorillas (polygyny) there are major differences in the size of testes due to process of copulation and attraction, as gorillas fight for the female whereas chimpanzees copulate with multiple partners
• humans have low sperm competition, roughly median line of primates
• sperm competition correlates to concentration of sperm in ejaculate
• bulls have less than half of the ejaculate volume of humans despite having 10x the amount of sperm concentration

Question 3

Preference of Clever Males in Budgerigars

Answer 3

Two male Budgerigars one-on-one with female, one that had learnt to open a shut container with food, started not being chosen. When the female’s container was taped shut, and the learning male was chosen.
- demonstrates female preference for problem solving skills when it can translate to more evolutionary strength.
- possibly relating to physical strength and not problem solving

Question 4

The Wandering Uterus Hypothesis

Answer 4

suggested that the uterus caused trouble for women by drifting over the body, confusing other organs and making women generally crazy

• education: too much learning around 13 to 17 would take all the energy for uterus growth
• travel: motor movements create unintentional erosion

Question 5

Influences of Hormones on Behaviour

Answer 5

• estrogen and progesterone can affect mood and behaviour
• small percentage of women are impacted by hormonal dysfunctions
• no evidence for cognitive impairment
• men and women have higher testosterone than estrogen and progesterone, however these are classified as the deciding factor

Question 6

Hormone Preconceptions on Research

Answer 6

• major use of male animals in basic research and clinical trials over females
• due to the greater control variables required to assess differences
• this means large amounts of animal research are only 50% represented theoretically

Question 7

Vulva Variations

Answer 7

• external organs
• cultural differences in ideals of beauty for size and shape
• largely variable, reflecting the lack of evolutionary pressure (males don’t care to choose specific models)

Question 8

Purpose and Hypothesis of Female Stimulation

Answer 8

purpose
- female pleasure encourages mating behaviour

• supports pair bonds - guarantees resources and protection for offspring

hypothesis
- causes negative uterine pressure - drawing sperm to egg
- evolutionary byproduct (such as male nipples) - if it was a factor in mating success then it should have evolved to be optimised and look similar across all people

Question 9

Effect of Sperm Competition on Bat Brain

Answer 9

• female promiscuous species had larger testicles and smaller male brains
• possibly, brain and testes require energy resource (metabolically expensive)

Question 10

Parental Care in Cane Toads

Answer 10

• after fertilised eggs, female and males separate and offer no support
• overcome by the volume of eggs laid
• 1% survive

Question 11

Weird Sex in Primates

Answer 11

Chimpanzees - females go 84 times with different males in a day

Orangutan - upside down

Question 12

Weird Sex in Insects

Answer 12

Praying Mantis - females bite head off during copulation to produce more sperm and use as a source of nutrients, offspring grow to be healthier
- mantis are sparsely distributed

Question 13

Weird Sex in Angler Fish

Answer 13

males bite into females so that male nervous system integrates with female’s, giving her control over ejaculation
- sparsely distributed