Task 3

Question 1

Reproductive success

Answer 1

The passing of genes on to the next generation in a way that they can too pass on those genes. This is not solely the number of offspring produced by an individual, but also, as Ronald Fisher outlined in 1915, the probable reproductive success of those offspring, making mate choice (a form of sexual selection) an important factor in this success

Question 2

Fitness of alleles

Answer 2

Quantitative representation of natural and sexual selection within evolutionary biology, can eb defined with respect to either a genotype or a phenotype

Question 3

Adaptive evolutionary change

Answer 3

Evolutionary changes that are adaptive to the given environment. Such changes increase survival and / or reproduction and are produced by natural selection

Question 4

Components of natural selection

Answer 4

Heritability, variation and competition.

Question 5

Purifying selection

Answer 5

Selective removal of alleles that are deleterious. This can result in stabilizing selection through the purging of deleterious variations that arise.

Question 6

Stabilizing selection

Answer 6

Type of natural selection in which the population mean stabilizes on a particular non-extreme trait value.

Question 7

Directional selection

Answer 7

Mode of natural selection in which an extreme phenotype is favoured over other phenotypes, causing the allele frequency to shift over time in the direction of that phenotype.

Question 8

Disruptive selection

Answer 8

Also called diversifying selection, describes changes in population genetics in which extreme values for a trait are favoured over intermediate values. In this case, the variance of the trait increases, and the population is divided into two distinct groups.

Question 9

Mutation-selection balance

Answer 9

Equilibrium in the number of deleterious alleles in a population that occurs when the rate at which deleterious alleles are created by mutation equals the rate at which deleterious alleles are eliminated by selection.

Question 10

Heterozygote advantage

Answer 10

Case in which the heterozygous genotype has a higher relative fitness than either the homozygous dominant or homozygous recessive genotype, often due to overdominance (single locus)

Question 11

Negative frequency-dependent selection

Answer 11

Fitness of a phenotype decreases as it becomes more common. The trait is only advantageous as long as it is the minority

Question 12

Force of mutation

Answer 12

For polygenic characteristics, the effective strength of mutation is proportional to the number of genes involved. Genetic variation will persist if the force of mutation is strengthened or that of selection weakened.

Question 13

Inconsistent selection

Answer 13

The environment changes fast over a short period of time so the selection that begun must be reversed

Question 14

Sexuallity antagonistic selection

Answer 14

The optimal phenotype for a male is not the same optimum for a female.

Question 15

Adaptationist stance

Answer 15

If some feature or behaviour is commonly found in a type of organism, then it is probably an efficient design solution to some problem that that organism has faced. If it were not, then the alleles building that feature would have been out-competed by alternatives that built a different feature

Question 16

Phenotypic gambit

Answer 16

The strategy of forming adaptationist hypothesis directly about the phenotype without needing to know what the genetic or developmental mechanisms that produce the phenotype are (validity of this can not be taken for granted).

Question 17

Ultimate explanation

Answer 17

Explanation of how that particular design increased ancestral fitness, ultimate explanation of a characteristic that increased compared to others

Question 18

Proximate explanation

Answer 18

Account of the genetical or developmental mechanisms that led to the formation of that characteristic in individual organisms (e.g. different genes, proteins etc.)

Question 19

Time lags

Answer 19

Period of time between one event and another

Question 20

Phenotypic plasticity

Answer 20

Ability of one genotype to produce more than one phenotype when exposed to different environments

Question 21

Genetic correlation

Answer 21

Estimate of the additive genetic effect that is shared between our pair of traits. For example, self-reported mood and physiological reactivity could both be heritable, but their genetic correlation can tell you if they are likely to share the same genes

Question 22

Shape of the adaptive landscape

Answer 22

Used to visualize the relationship between genotypes and reproductive success

Question 23

Optimality modelling

Answer 23

Tool used to evaluate the costs and benefits of different organismal features, traits, and characteristics, including behaviour, in the natural world. This evaluation allows researchers to make predictions about an organism’s optimal behaviour or other aspects of its phenotype.

Question 24

Sexual dimorphism

Answer 24

Condition where the two sexes of the same species exhibit different characteristics beyond the differences in their sexual organs.

Question 25

Sexual selection

Answer 25

Natural selection on the ability to gain mates

Question 26

Intrasexual selection

Answer 26

Selection on the ability to compete with rivals from the same sex

Question 27

Intersexual selection

Answer 27

Selection on the ability to attract members of the opposite sex

Question 28

Bateman’s principle

Answer 28

The principle that males gain more reproductive success from each additional mating partner than females do

Question 29

Intrasexual competition

Answer 29

The competition between 2 individuals of the same sex

Question 30

Sexy son hypothesis

Answer 30

Proposed by Ronald Fisher in 1930, states that a female’s ideal mate choice among potential mates is one whose genes will produce male offspring with the best chance of reproductive success.

Question 31

Good genes hypothesis

Answer 31

Explanation which suggests that the traits females choose when selecting a mate are honest indicators of the male’s ability to pass on genes that will increase the survival or reproductive success of her offspring

Question 32

Extra-pair mating

Answer 32

Mating behaviour n socially monogamous species

Question 33

Biological adaptations

Answer 33

Attribute that helps a creature to survive and reproduce, become better suited or fit to an environment as an historical end product of the process of evolution

Question 34

Hitch-hiking traits / genetic hitchhiking

Answer 34

an allele changes frequency not because it itself is under natural selection, but because it is near another gene that is undergoing a selective sweep and that is on the same DNA chain.

Question 35

Trade-off traits

Answer 35

Arises when two traits have opposite effects on fitness but are genetically correlated with each other

Question 36

Local resource competition

Answer 36

Relatives compete with one another since the local resources are limited

Question 37

Local resource enhancement

Answer 37

occurs when relatives help one another instead of competing with one another in LRC

Question 38

Sex-role reversal

Answer 38

When males do all the post-fertilization care the cost asymmetry between the sexes is reversed (i.e. the males are choosier; Females will be larger/ more ornamented etc.)

Question 39

Nomological networks

Answer 39

Representation of the concepts (constructs) of interest in a study, their observable manifestations, and the interrelationships among and between these.

Question 40

Absolute fitness

Answer 40

How many genes contribute to the gene pool of the next generation

Question 41

Relative fitness

Answer 41

The contribution an individual makes to the gene pool of the next generation, relative to the other contributions of other individuals