Chapter 2 - Principles

Question 1

Natural Selection

Answer 1

The prime mover of evolutionary
change. The name given by Darwin to what is today considered to be differential gene replication. May more loosely be described as differential reproductive success of different phenotypes.

Question 2

Reproduction success hypothesis

Answer 2

The notion that evolutionary
‘improvements’ to members of a species counteracting changes in members of other species, which may for example be parasites of that species, lead members of the first species
back to where they started

Question 3

Heritable variation

Answer 3

individuals within a population tend to differ from each other in ways that are passed
on to their offspring

Question 4

Fitness

Answer 4

A measure of the number of offspring produced, or, in the view of some evolutionists,
the proportion of genes passed on to future generations

Question 5

Genes

Answer 5

The fundamental unit of heredity; a section of DNA that codes for one polypeptide. Since
proteins are made up of polypeptides then we can say that genes code for proteins.

Question 6

Chromosomes

Answer 6

A string of genes found in a cell’s
nucleus.

Question 7

Genotype

Answer 7

The genetic constitution of an organism encoded in the nucleus of each cell of the body.

Question 8

Phenotype

Answer 8

Individual characteristics resulting from environmental interaction of an organism’s
genotype

Question 9

Mutation

Answer 9

A random inherited change in genetic material

Question 10

DNA

Answer 10

deoxyribonucleic acid) The chemical of which genes are composed. Physically it is a
giant double helix molecule

Question 11

Heritability of characteristics

Answer 11

The extent to which variation in a trait is due to genetic rather than environmental components.

Question 12

Genome-wide association studies

Answer 12

A method used in genetics research which scans the entire genome in a large sample in order to identify specific
genetics variations

Question 13

Behavioural epigenetics

Answer 13

A sub-discipline of behavioural genetics which is devoted to the way in which environmental cues affect the activation of genes involved in difference between people in their behaviour

Question 14

Group selection

Answer 14

The notion that natural selection
occurs at the level of the group

Question 15

Individual selection

Answer 15

The notion that natural
selection occurs at the level of the individual

Question 16

Gene selection

Answer 16

The notion that natural selection
occurs at the level of the gene

Question 17

Altruism

Answer 17

Self-sacrificing behaviour. To an
evolutionary psychologist true altruism involves behaviour that promotes the inclusive fitness of
another at a cost to oneself

Question 18

The selfish gene

Answer 18

Genes are considered selfish since alleles in the past which affected bodies to promote
copies of themselves at the expense of others are the ones that are with us today. the gene which is most ‘selfish’ may in theory be immortal via copies of itself that it leaves. So selfish in this context merely means affecting the organism to make one’s own replication
likely with no purposive state intended

Question 19

Locus

Answer 19

A gene for a particular characteristic occurs at a specific point on the chromosome

Question 20

Alleles

Answer 20

a locus is home to more than one alternative form of a
gene; when this occurs the alternate forms a

Question 21

Heritability

Answer 21

The estimation of the extent to which we are able to breed for a characteristic

Question 22

Genetic Drift

Answer 22

The process of changes in gene
frequencies in a population due to chance

Question 23

Gene flow

Answer 23

When animals move from one population to another they may, by chance, have a genetic makeup different from the new population. If the new makeup confers an advantage in the new local environment then the population can alter quite rapidly

Question 24

Inclusive Fitness

Answer 24

A measure of the proportion
of an individual’s genes passing on to future generations directly via offspring and indirectly
via other relatives

Question 25

Multilevel selection theory

Answer 25

The hypothesis that natural selection acts at the level of the group in addition to acting at the level of the gene/individual. Associated with David Sloan Wilson and Elliot Sober

Question 26

Reciprocal Altruism

Answer 26

The process of reciprocating acts of self-sacrificing behaviour between two individuals such that both ultimately gain because the benefits outweigh the costs for each (often termed ‘direct reciprocation’ simply ‘reciprocation’ today). First proposed by Robert Trivers in 1971. Note that ‘indirect reciprocity’ involved a third party providing the benefit to the recipient

Question 27

Direct and Indirect Reciprocity

Answer 27

‘direct’ because the recipient of the ‘altruism’ later repays the initial actor indirect reciprocity, whereby third parties may provide benefits due to a person’s reputation for ‘altruistic’ behaviour

Question 28

Cost signalling theory

Answer 28

The situation whereby an individual sends out signals of desirable characteristics that are too costly to fake.