Evolution, Genes, Environment & Behaviour

Question 1

What is evolution?

Answer 1

A gradual change over time in organic life from one form to another

Question 2

What is natural selection?

Answer 2

The idea that characteristics that increase the likelihood of survival and reproduction will be more likely to be preserved in the population, therefore becoming more common in the species over time

Question 3

What are mutations?

Answer 3

Random events in gene reproduction during cell division
They give rise to adaptations

Question 4

What are adaptations?

Answer 4

Physical or behavioural changes that allow organises to meet recurring environmental challenges to their survival, thereby increasing their reproductive ability

Question 5

What is biological inheritance?

Answer 5

How traits and tendencies are transmitted from one generation to the next

Question 6

What are alleles?

Answer 6

Alternative forms of a gene that produce different characteristics

Question 7

What does it mean if an allele is dominant?

Answer 7

The characteristic that it controls will always be displayed in the phenotype

Question 8

What does it mean if an allele is recessive?

Answer 8

The characteristic that it controls will only be displayed in the phenotype if both copies of the recessive allele are passed down

Question 9

What is a genotype?

Answer 9

The specific and complete genetic makeup of an individual

Question 10

What is a phenotype?

Answer 10

The individual’s overt observable characteristics

Question 11

Why can identical twins display different characteristics?

Answer 11

They share the same genotype but they have different interactions with the environment, causing their phenotypes to differ

Question 12

What are genes?

Answer 12

Functional segments of DNA that code for proteins

Question 13

What are chromosomes?

Answer 13

Single or double-stranded, tightly-coiled molecules of DNA and proteins
There are 46 of them in all body cells, other than sex cells (23) and red blood cells (0)

Question 14

What is monogenic transmission?

Answer 14

When one gene pair contributes to one phenotypic trait

Question 15

What is polygenic transmission?

Answer 15

When multiple gene pairs contribute to one phenotypic trait

Question 16

What is ethology?

Answer 16

The study of animal behaviour
It is focused on the evolutionary differences between species

Question 17

What are inherited behavioural characteristics?

Answer 17

Traits organisms are born with that help promote the chances of survival and reproductive success

Question 18

Give an example of an inherited behavioural characteristic

Answer 18

A fixed action pattern - an unlearned behaviour that is automatically triggered by a particular stimulus

Question 19

What is behavioural genetics?

Answer 19

The study of how heredity and environmental factors influence psychological characteristics

Question 20

What is the degree of relatedness?

Answer 20

The number of genes we share with others by direct common descent

Question 21

What is the concordance rate?

Answer 21

A statistical expression of the probability that two individuals with shared genes will share a particular trait to the same degree

Question 22

What is a shared environment?

Answer 22

An environment in which its members experience many common features

Question 23

What is a non-shared environment?

Answer 23

An environment in which its members experience different features

Question 24

How are adoption studies conducted?

Answer 24

Adopted people are compared to both their biological and adopted parents
If a trait is inherited genetically then you would expect to see it present in the biological parents and not the adoptive parents

Question 25

How are twin studies conducted?

Answer 25

Trait similarities are compared between monozygotic and dizygotic twins
If a trait is inherited genetically then you would expect the concordance rate for monozygotic twins to be higher than for dizygotic twins
Studies where monozygotic twins are raised apart are even better - they provide stronger evidence that the concordance is not due to the environment

Question 26

What is heritability?

Answer 26

A statistical estimate of the extent to which the variation in a specific phenotypic characteristic within a group of people can be attributed to their differing genes

Question 27

What is the reaction range?

Answer 27

The range of possibilities that a genetic code allows for

Question 28

What determines where in the reaction range an individual’s phenotype lies?

Answer 28

The environment

Question 29

What is evolutionary psychology?

Answer 29

Seeks to explain how evolution shaped modern human behaviour by considering species characteristics more generally
It is interested in the genetic commonalities between people

Question 30

Give two behaviours posed by evolutionary psychology in which genetic fitness does not necessarily refer to the strongest or fastest individual

Answer 30

Kin selection
Reciprocal altruism

Question 31

What is kin selection?

Answer 31

The evolutionary strategy in which behaviours are selected that favour the reproductive success of an organism’s relatives even if at cost to the organism itself

Question 32

What is reciprocal altruism?

Answer 32

The behaviour in an organism that reduces its fitness to survive and reproduce while increasing another organism’s fitness, with the expectation that this favour will later be returned

Question 33

Give some culturally universal characteristics

Answer 33

Infants are born with the ability to acquire any language
New-borns are able to perceive specific stimuli without any experience of them (e.g. facial expressions)
Basic emotions are universally recognised