Speciation

Question 1

Speciation

Answer 1

The process where a group of individuals within a population become reproductively isolated to their larger population forming a new species

Question 2

Species

Answer 2

a group of organisms that interbreed under natural conditions and are reproductively isolated from other species.

Question 3

pre-zygotic RIMs

Answer 3

Geographic
Ecological
behavioural
gametic
mechanical
temporal

Question 4

post zygotic RIMs

Answer 4

hybrid breakdown, inviability and sterility.

Question 5

polyploidy

Answer 5

Where an organism has more than two sets of chromosomes in its somatic cells (>2n).

Question 6

Autopolyploidy

Answer 6

Homologous chromosomes do not separate during meiosis, leading to diploid number of chromosomes present in the gametes

Question 7

Allopolyploidy

Answer 7

The process where two different species produce an infertile hybrid. chromosome doubling can lead to new (instant) species

Question 8

Deme

Answer 8

A subset of a population where there is limited gene flow with members of the larger population

Question 9

Cline

Answer 9

The gradual change of characteristics between neighbouring populations related to the change in biotic and abiotic factors in a given range.

Question 10

Genetic Flow

Answer 10

the transfer of genetic material from one population to another usually by migration

Question 11

Genetic Drift

Answer 11

the process of change in genetic composition of a population due to chance or random events

Question 12

Population bottleneck

Answer 12

A sharp reduction in the size of the population due to environmental events or human activities

Question 13

founder effect

Answer 13

A small number of individuals emigrate from a population or become geographically isolated from their original population

Question 14

divergent evolution

Answer 14

when two species diverge from a common ancestor and develop different characteristics.

Question 15

homologous structures

Answer 15

structures that have similar evolutionary history but have developed to suit different functions

Question 16

convergent evolution

Answer 16

The proc two different species evolve similar characteristics due to facing similar selction pressures.

Question 17

analogous structures

Answer 17

Various structures in different species that have the same function but have evolved differently. They do not share a common ancestor

Question 18

co-evolution

Answer 18

Changes in one species lead to reciprocal changes in another. They evolve together as they exert different selection pressures on each other.

Question 19

gradualism

Answer 19

The process of evolution through the accumulation of many small changes at a regular rate over a very long period of time

Question 20

punctuated equilibrium

Answer 20

evolution through periods of stasis punctuated by sudden change in species due to sudden changes in the environment

Question 21

Adaptive radiation

Answer 21

The rapid formation of multiple new species diverging from a common ancestor to occupy newly available and different niches.

Question 22

Natural Selection

Answer 22

The process whereby organisms better adapted to their environment tend to survive and produce more offspring

Question 23

Disruptive selection

Answer 23

The outcome of natural selection against the phenotypic median favouring variants at opposite extremes of the trait

Question 24

Directional selection

Answer 24

The outcome of natural selection against one extreme of a trait, shifting the phenotypic median to the other extreme.

Question 25

Stabilising selection

Answer 25

The outcome of natural selection selecting against the two extremes of a trait and favours the phenotypic median.

Question 26

vestigial structures

Answer 26

An unused feature that is a historical remnant of a structure that served a purpose in the organism’s ancestor.

Question 27

allopatric speciation

Answer 27

species evolving due to a geographic barrier.

Question 28

sympatric speciation

Answer 28

When populations form a new species within the same geographical area as the parent species.

Question 29

cladogenesis

Answer 29

Evolution that results in the splitting of a lineage where the parent species splits into at least two species.