• Directions: • Title pg. 97 “Evolution of Populations”• Divide your page 97 into 10 different boxes. • Number the boxes 1-10

Evolution of Populations

Population- group of organisms of the same species that interbreed

#1

Gene Pool-all the genes (alleles) present within a population

#2

Important!

• Natural selection works on the phenotype, not the genotype!

#3

Allele Frequency (Relative)- the number of times an allele will appear in a gene pool

Total- 6

R- 3 50%

r- 3 50%

rR RR

r r

#4

#4R- 48r- 52

What are the allele

frequencies? “R” has an allele frequency of 48%“r” has an allele

frequency of 52%

What can introduce variation into a population? 1)Mutation2)Gene Shuffling from Independent

Assortment

#5

Genetic Variation is important! Why?! -enables greater survival in a changing environment

#6

Genetic Equilibrium- -When allele frequencies remain the same.-No change, no evolution

#7

Genetic Equilibrium Requirements1)Random mating2) Large population3) No immigration or emigration4)No mutations5) No natural selection

#8

Genetic Drift-Random change in allele frequency due to small populationsNo benefit nor harm

#9

How does Genetic Drift occur?1)Bottleneck Effect: only a few survivors from an original population

contribute their alleles

#10

2) Founder Effect:A subgroup of the population immigrates to and colonizes a new area, changing allele frequencies.

#10

Types of Evolution:

Adaptive RadiationOne species can evolve into many diverse forms