1. Evolution & Biological Classification
TSW Identify & describe the selective forces that “drive” evolution
TSW Describe natural selection & its role in evolution

2. 2 Goals for ALL living things
Survive and reproduce
All behaviors/morphology/physiology are geared or “adapted” to meet these goals

3. Where do we “Get” these traits?
Nature: We are born with these-genetic make-up coded in our DNA from our parents to distant ancestors
Nurture: We are taught directly or indirectly by our environment & our experiences

4. How do we know that organisms have evolved?
Look at fossils for comparative anatomy
Look at biochemistry for comparative processes
Look at molecular biology for DNA sequences

5. Evolution
The process by which the genetic compositions of POPULATIONS of organisms change over time
Evolution does NOT happen to INDIVIDUALS

6. Genetic Mutation
The raw material of evolution which is acted on by natural selection

7. Natural Selection
Process explaining why organisms that possess variations (mutations) that are best suited to the environment will be most likely to survive and reproduce

8. 4 Premises of Natural Selection
All organisms produce more offspring than can possibly survive to reproduce
There is a great deal of variation in traits among individuals in natural populations, many of which can be inherited

9. 4 Premises of Natural Selection
3. Resources (food, light, space) are limited, therefore, there must be competition
4. Individuals with traits better suited to their environment survive to reproduce more of their kind

10. Traits
Not all traits are good, some are just “along for the ride” because they are “linked” to beneficial traits
Some are neutral- they don’t carry an advantage or a disadvantage…they are just there