3.7.2 and 3.7.3 Populationsand Evolutions may lead to speciation

All alleles of all genes of all individuals in a population at one time

Proportions of an allele within a gene pool

All the individuals of one species in same area at same time that can interbreed to produce fertile offspring

used to calculate allele frequency in a population

Allele frequency of alleles remain same from one gen to next which relies on 5 assumptions being:
- NO SELECTION
- NO MUTATION
- NO MIGRATION
- LARGE POPULATION
- RANDOM MATING

p + q = 1
p = frequency of dominant allele
q = frequency of reccessive allele

p$^2$+2pq +q$^2$ = 1
p$^2$= frequency of dominant genotype
2pq = frequency of hetero genotype
q$^2$= frequency of recessive genotype

Disruptive selection can lead to speciation

Evolution of a new species from an existing one
Occurs when one population splits and becomes reproductively isolated

Allopatric(geographically)
Sympatric(changes in reproductive mechanisms)

Mutation leading to different courtship sequences
Mutation leading to becoming fertile at different times

Change in allele frequency in a population from one generation to the next
The smaller the population the bigger impact a change in allele frequency does.
Evolutions occurs must faster in smaller populations

1)A population with genetic variation live together in an area
2)Habitat is split due to geographical barrier splitting the population into two, preventing them from interbreeding
3) Both groups will suffer different selection pressures leading to different alleles being favoured
4)Over time the allele frequencyand phenotypes of groups will be so different they aren't classified as same species (cant interbreed)