1. Animal Behavior (Ethology) and Evolution
Unit 8
Animal Behavior (Ethology) and Evolution

2. Day 3
Evidence of Evolution

3. Evolution
Change in a population over time

4. Evolution theories Lamark- use and disuse
The more a structure is used, the bigger and better it gets
Structures not used, decrease and disappear
These traits (acquired characteristics) that develop during life are passed to offspring but not through genes

6. Evolution theories Darwin- Father of Evolution
Origin of Species- book that discussed the theory of natural selection
“Survival of the Fittest”- organism best suited to the environment will survive and reproduce and pass traits to the next generation

7. Natural selection
Organisms most fit to environment survive and reproduce passing these adaptations to the next generation
Ex: Runt of the litter is the least likely to survive
Ex: Peppered Moth of England
Color was white until the industrial revolution left light bark trees dark. Species mutated to the dark colored moth due to camouflage

8. Natural selection Variation: Caused by sexual reproduction
Occurs within a population when it needs to adapt to environment
Caused by gene shuffling during fertilization and crossing over or when a positive mutation occurs
Over-reproduction: more offspring are produced in each generation than can survive
Competition: Due to individuals living in the same area and having the same niche (job)

9. Evidence of Evolution Fossils
Old layers in lower rock layers, new fossils in upper rock layers
Fossils tell that fewer organisms were on Earth in earlier eras and that they were less complex

10. fossils Form in sedimentary rock
Imprints, molds, casts, petrified fossils
Relative age of fossils can be determined from the layer of rock the fossil is in
Old fossils in bottom layers and young in upper layers
Absolute age- radioactive isotopes, carbon 14, half life

12. Evidence of evolution Comparative Anatomy
Vestigial structures- have no function
Ex: Appendix, pelvis of a whale
Homologous Structures- looks the same but have different functions
Ex: bones in the hand and flippers
Analogous structures- look different but have the same function
Ex: wings of a bird and insect

14. Evidence of evolution Embryology- study of embryos
Compare embryos of different species at different stages of development
More alike, more related

16. Evidence of evolution Biochemical comparison
#1 thing scientists use to group/ classify based on evolutionary relationships
Compare organisms proteins and their DNA
Only 1% difference in the DNA or a chimp and a human