Week 3 - Function

Question 1

How is the function of behaviour ‘designed?’

Answer 1

Designing agent = selection
- Selection: provides an advantage to a challenge

Acts to sift variants of behaviour - favouring those that provide their bearer with greater representation in the next generation

Selection for SURVIVAL: natural selection (evolution by descent)

Question 2

Example of Behaviour Function: Japanese Macaque

Answer 2

Adaptations to cold weather
- Rubbing each other’s limbs
- Bathing in hot springs

Question 3

What is the ‘sexual struggle’?

Answer 3

Between individuals of the same sex - generally the males - in order to drive away/kill their rivals

Between individuals of the same sex - in order to excite or charm those of the opposite sex which select the more agreeable partners

Question 4

How does natural selection work in practice?

Answer 4

1. Huge number of individuals are produced
2. Insufficient resources for all, so many die before reproducing (illness/disease etc.)
3. Individuals vary in attrbutes
4. Individuals with attributes better suited to environment are less likely to die
5. These individuals will be over represented in the next generation - as they can survive to breed

All about SURVIVAL

Question 5

What two things do behaviours function to maximise?

Answer 5

1. Likelihood of long-term survival
2. Lifetime reproductive output

Question 6

Example of reproductive output: Red-Breasted Goose

Answer 6

Builds nest on ground
ISSUE: breeding season is also breeding season for white artic fox
SO: it breeds and puts nest in another one of its predators the SNOWY OWL
BECAUSE: Snowy owls hunt away from their own nests

Maximise their chance of survival and some young surviving to reach adulthood

Question 7

What behaviours maximise survival?

Answer 7

HIDING from predators

ESCAPING from predators

INCREASING FOOD eaten (more energy)

REDUCING ENERGETIC COSTS (to regulate homeostasis)

Question 8

What behaviours aid reproduction?

Answer 8

Increasing ATTRACTIVENESS

Increasing ACCESS TO MATES

Increasing FECUNDITY (eg. by being in better condition to raise their young)

Increasing SURVIVAL OF YOUNG (feed them, parent them, give them resources)

Question 9

What are dysfunctional behaviours?

Answer 9

UNUSUAL behaviours - do have a usefulness to a population BUT comes with an extreme costs

Eg. Prairie Dog - one animal scans for predators and gives an alarm call (while rest of population hide back in the burrow)

Question 10

Who benefits from social behaviours?

Answer 10

DIRECT: benefits to individual performing behaviour

INDIRECT: others in population, offspring

SYMBIOSIS - benefits to an unrelated species