speciation and genetic drift

Question 1

speciation

Answer 1

development of a new species from an existing species when populations of the same species become reproductivey isolated
changes in allele frquency can cause changes in phenotype which means they cant succesfully interbreed

Question 2

allopatric speciation

Answer 2

1. geographical isolation
2. live in different conditions
3. different selection pressures
4. different changes in allele frequencies could occur
5. leads to differences in gene pool causing changes in phenotype frequencies
6. eventually wont be able to successfully interbreed to produce fertile offspring - reproductively isolated

Question 3

sympatric speciation

Answer 3

1. random mutations within a population

2. members can no longer successfully interbreed

Question 4

changes in phenotypes that can prevent individuals from breeding successfully

Answer 4

1. seasonal - different flowering or mating seasons / become sexually active different times of year
2. mechanical - changes in genitalia
3. behavioural - courtship rituals that arent attractive to main population

Question 5

genetic drift ( a type of evolution)

Answer 5

1. chance rather than environmental fators dictate which individuals survive breed and pass on alleles
2. usually has a greater effect in small populations where chance has a greater influence
   larger populations any chance variations even out across whole population

Question 6

what works together to drive evolution

Answer 6

natural selection and genetic drift

Question 7

what is responsible for great diversity in organisms

Answer 7

speciation and evolutionary change