1. Evolution

2. Evolution- change in allele frequency in a population over time (decent with modification)
Population- Group of individuals of a single species that occupy the same general area
Allele- an alternative version of a gene
Gene- a discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA, codes for a protein that leads to a physical characteristic

3. Types of Evolution Microevolution- evolution within a species
Macroevolution- evolution that produces a new species
Origins of life according to evolution

5. Lamarckian Evolution Lamarck’s theory is incorrect 3 concepts
Theory of need
Theory of use and disuse
Theory of inheritance of acquired characteristics

6. Charles Darwin Naturalist on the HMS Beagle Surveying ship
5 year voyage beginning in 1831
Made observations and collected specimens along the way, many from the Galapagos Islands
Returned to England and began to develop his theory of Evolution

7. Galapagos finches that Darwin observed have different beaks based on the food that they eat
Darwin believed the differences in their beaks were due to evolution
He believed the different species of finches adapted to different environments at different times, so they could get the food that was available there
Darwin believed they evolved from a common ancestor

8. Artificial Selection
Species definitely have the ability to change over time to become very different than what they once were

9. Charles Darwin
Published “On the Origin of Species by Means of Natural Selection” in 1859
Published “The Descent of Man” in 1871

10. Evolution by Natural Selection
Mechanism of evolution- evolution is what happens, natural selection is how it happens
Individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to have more offspring than other individuals which leads to the accumulation of favorable traits in a population over generations

11. Evolution by Natural Selection
Traits must be genetically based
Genes must lead to a reproductive advantage
Causes the allele frequency in the population to change
Takes many generations
Remember: favorable traits are based on the environment

12. Survival of the fittest
Somewhat misleading
Does not necessarily mean physical strength
It means better adapted to the current environment

13. What leads to natural selection?
Environmental change- an allele that was once not an advantage becomes an advantage because the environment is different.
Immigration (gene flow)- individuals with more advantageous genes join a population.
Genetic drift- random selection of a gene because of an event that significantly decreases population size and eliminates all or most individuals with a particular gene.
Mutation- altering of the nucleotide sequence can make a gene more advantageous.

14. Microevolution Pests and pesticides
Bacterial resistance to antibiotics
Selection to avoid predation
Microevolution- evolution within a species