Evolution

Question 1

Darwin’s theory of evolution

Answer 1

functionalism - characteristic useful for survival
mechanism of natural selection
- differences inherited
- desirable characteristics passed on to become more dominant
- mutations
adaptive radiation
- single species evolves to match survival
- little competition and diverse resources

Question 2

brief history

Answer 2

• earliest mammal - small, nocturnal, predator
• hominids in Africa - left 1.7 million years ago
• late development - rapidly growing brain and behaviour

Question 3

existing relatives

Answer 3

closest are chimpanzees and gorillas (share 99% DNA)
DNA analysis suggested little differences

Question 4

human brain evolution

Answer 4

elephant brain = 0.2%
human brain = 2.3%
shrew brain = 3.3%
neurons and complexity is key:
bipedalism, opposable thumbs, colour vision, linguistics
Herculano - Houzel et al - brain weight to neurons, primates have the most neurons
changes in the neocortex - slowing of maturation, time for growth
not all neurons are coded at birth
neonatal = 350g
adult - 4000g

Question 5

why study non human species?

Answer 5

similarities in function and structure

Question 6

importance of animal models

Answer 6

• hippocampal lesions in rats
• impaired conditional to contextual cues
• amnesia in humans
• rats = neuronal systems

Question 7

comparative studies

Answer 7

• role of hippocampus in memory
• volume is enlarged in food storing species
• changes in size in response to experience

Question 8

evolution shaping: psychological mechanisms

Answer 8

game theory - Von neumann
- mathematical model of strategic decisions
- analysis of outcome based on own and other decisions
- no control on others’ decisions
Maynard Smith and Price
evolution strategies
ESS and price equation

Question 9

Hawk dove game

Answer 9

cooperation vs conflict
Hawk: aggressive and uses force if necessary
Dove: passive, avoids conflict and shares
1. both encounter a food source - benefit vs cost

hawk/hawk - fight, winner ger resource
hawk/dove - hawk dominates, takes resource
dove/dove - both passive so they share

Question 10

evolutionarily stable strategy

Answer 10

• cannot be invaded by alternative
• best strategy for survival
  1. do better than alternative
  2. comparable pay off

Question 11

prisoners dilemma

Answer 11

2 arrested for same crime, no communication
1. silent = both 1 year
2. 1 confess - 5 years
3. both confess - 3 years each
Axelrod and Hamilton
- biological interactions
- cooperation
- computer simulation = cooperation as ESS, 2 meeting = high probability

Question 12

altruism

Answer 12

behaviour as a cost to oneself, not to others
survival of the fittest - best at passing on genes
- higher fitness = more offspring

Question 13

kin selection

Answer 13

• inclusive fitness
• Hamilton’s rule
• price equation: connected to inclusive fitness, if cost to individual, to individual fitness, net effect increases, altruism increases

Question 14

altruism towards relatives

Answer 14

• meerkat stands guard - reduced survival but benefits groups
• overall survival increases
• ESS and involves within population

Question 15

non kin altruism

Answer 15

reciprocal altruism - Tajfel
- benefits reciprocated
- price equation
- iterated Prisoner’s dilemma
group selection
- more cooperation - dominate selfish groups