Unit 5 Evolution. What is Evolution? Evolution: Microevolution Change in a population’s genetic structure over time Change in: alleles/genotype.

Unit 5 EvolutionUnit 5 Evolution

What is Evolution?What is Evolution?Evolution:

MicroevolutionMicroevolutionChange in a population’s genetic

structure over timeChange in: alleles/genotype

Causes of MicroevolutionCauses of Microevolution

Genetic drift: Random changes in frequency of alleles in a population

Gene flow: change of alleles due to migration into or out of a population

Mutation: random change in individual’s genotype

Natural selection: survival of the fittest

Which causes of Which causes of microevolution form microevolution form adaptations?adaptations?

What is an example of human adaptation?

MacroevolutionMacroevolutionMassive change to earth causing:

DNA DNA

What is the purpose of DNA?

Mutations (changes in Mutations (changes in DNA)DNA)How can mutations affect an

individual?

How can mutations affect a population?

Changes in genotypeChanges in genotype

How can the genotype of an individual change?

How can the genotype of a population change?

Change in PhenotypeChange in Phenotype

How can the phenotype of an individual change?

How can the phenotype of a population change?

Variety in Populations Variety in Populations (adaptations)(adaptations)What are adaptations?

How do adaptations form in a population?

Changes in the allele Changes in the allele frequency within the gene frequency within the gene poolpoolWhat is the allele frequency?

How can it be changed in a popultion?

New SpeciesNew Species

How do new species form?

What must they do to survive?

What happens if the species cannot survive?

Charles DarwinCharles Darwin

1. Darwin proposed the theory of natural selection

2. Natural Selection: organisms pass more favorable traits to offspring ensuring survival

1. “Survival of the Fittest”

3. Publish book, “Origin of Species” in 1859

Darwin’s Theories

1. Descent w/ modification: younger fossils are a modification of their ancestors

1. Example:

2. Similar fossils of a species were found in close locations

3. Similar Species share a:

C. Darwin’s TheoriesC. Darwin’s Theories4. Adaptation: trait acquired to

survive changes5. Fitness: ability to pass on favorable

traits to offspring6. Adaptive Advantage: traits that

enable a species to survive better in its environment

Peppered Moths