evolutionary theory

Question 1

what are the three types of selection

Answer 1

artificial
natural
sexual

Question 2

what is artificial selection

Answer 2

humans have selected the most desirable traits of a species and bred these together heading towards a particular direction in order to gain e.g more nutritional value, more use to humans etc
e.g bananas have been selectively bred over 7000 years to become sweeter, easier to get into, longer and have softer seeds

Question 3

what three things are crucial for artificial selection

Answer 3

variation
heredity
selection in a clear direction e.g breeding dogs for tameness must be done consistently over many years

Question 4

who is doing the selecting in each type of selection

Answer 4

artificial: human breeder
natural: natural pressures e.g predation, drought etc
sexual: natural pressures from within species related to reproduction e.g choice of opposite sex

Question 5

what are physical adaptations

Answer 5

characteristics a species has which have been selected and allows better survival in environment
-brought about by small incremental changes due to mutation which have been selected for
-e.g darwins finches

Question 6

what are the main ideas surrounding behavioural adaptations

Answer 6

body contains adaptations, does the brain too?
-evolutionary psych.: cognitive mechanisms
-ethology: studying behaviour in a natural habitat
-behavioural ecology: extension of ethology, more focused
-sociobiology: gene centric focus on social behaviour

Question 7

what are the behavioural adaptations

Answer 7

Barkow, Cosmides and Tooby 1995
-predisposed fear (scared of spiders but not cars)
-mating preferences
-emotional states
-cheater detection
-helping behaviour
-face processing/perception

Question 8

what are the 6 criteria for adaptations

Answer 8

Schmitt and Pilcher 2004
-functional
-universal
-interactive
-complex
-efficient
-modular

Question 9

if an adaptation does not meet the criteria, then what may it be

Answer 9

• By product
• Exaptation (unselected function e.g ears to hold glasses)
• Noise (non functional left overs e.g appendix, hiccups)
• Malfunction e.g phobias

Question 10

how to spot an adaptation

Answer 10

Tinbergen’s 4 qs
-mechanism (present/how): what is the behaviour, how is it constructed?
-adaptation (present/why): is it an adaptation, how does it contribute to survival?

-ontogeny (history, how): developed only when exposed to food gone bad
-phylogeny (history, why): old and widespread, found in all mammals

Question 11

what are the issues with studying behavioural adaptations

Answer 11

Lewis 2017
- we cannot go back in time
- susceptible to ‘just so’ stories
- struggles to account for some behaviours e.g homosexuality
- ethical issues, naturalistic fallacy ‘is’ vs ‘ought’ history