Evolution

Question 1

Microevolution

Answer 1

small changes within a species

Question 2

Macroevolution

Answer 2

bigger evolutionary changes that can occur throught repeated microevolution or major environmental changes resulting in new species forming

Question 3

Positive Allele Selection

Answer 3

Positive allele selection promotes the spread of beneficial alleles by favouring a heritable trait that will increase within a population

Question 4

Negative allele selection

Answer 4

hinders the spread of negative alleles by disfavouring a heritable trait which will decrease in a population

Question 5

Gene pool

Answer 5

the total soum of all the alleles of all genes of all individuals in the population

Question 6

Stabilising Selection - what is it and what causes it

Answer 6

Natural selection that maintains consistency of a mean phenotype population while lowering the phenotypic extremes.
Caused by a stable environment over a long period of time.

Question 7

Directional Selection what is it and what causes it

Answer 7

Natural selection that favours one phenotypic extreme causing the allele frequency to shift over time in the direction of that phenotype to establish a new mean - caused by a sudden change in the environment

Question 8

Disruptive selection what is it and what causes it

Answer 8

Natural selection that favours individuals with extreme phenotypes splitting the mean - caused by a rare environmental change such as soil contamination by mining

Question 9

Gene flow

Answer 9

the movement of alleles in and out of a population

Question 10

Genetic Drift

Answer 10

changes in the gene pool and relative frequency of alleles in a small population due to chance

Question 11

Founder Effect

Answer 11

reduced genetic diveristy as a result of a population having descended from a small number of colonising ancenstors

Question 12

Population bottleneck

Answer 12

an event that drastically reduces the size of a population and thus its genetic diversity

Question 13

Divergent evolution

Answer 13

The process whereby groups from the same common ancestor evolve and accumulate differences, resulting in the formation of new species - galapogas finch

Question 14

Parallel evolution

Answer 14

independent evolution of similar traits in species that once shared a common ancestor despite geographical isolation - Australian marsupials and placental mammals

Question 15

Convergent Evolution

Answer 15

the independent development of similarities between species as a result of similar selection pressures and ecological roles - shark and dolphin

Question 16

Coevolution

Answer 16

when two or more species affect each other’s evolution - prey adapting to predator which in turn adapt to prey

Question 17

Speciation

Answer 17

devolpment of new species formed due to evolution

Question 18

Allopatric speciation

Answer 18

when two populations of the same species become isolated from each other due to geographic barriers

Question 19

Sympatric Speciation

Answer 19

When populations of a species become reproductively isolated from each other while they share the same habitat - rare

Question 20

Parapatric speciation

Answer 20

when two subpopulations of a species evolve reproductive isolation with each other due to habitat differences within the population range - reduced gene flow but not total isolation