1. Happy Tuesday!
Lets do a Quickwrite
1. List the 5 requirements for Natural Selection to occur.

2. Over production
Variation
Struggle to survive
Survival of fittest
Populations evolve

3. Evidence Supporting Evolution
Even Very Good Friends Hiccup
Embryonic, Vestigial, Genetics, Fossils, Homologous structures

4. 1. Embryonic Similarites
The same groups of cells develop in the same order and in similar patterns in all vertebrates.
The more alike the embryo stages are, the more closely related the organisms are thought to be.
Examples: Turtles, chickens, rabbits, and humans all appear similar as embryos!

5. 1. Embryonic Similarities

6. 2. Vestigial Structures
Structures in organisms left over from ancestors that have no known functions.
Examples:
Leg bones in skinks
Appendix in humans
Tailbone in humans

7. Legless Skink

8. 3. Comparative Anatomy
The study of the structures of different organisms

9. Homologous Structures
Anatomy that is similar in structure and origin
Not always similar in function
This shows an evolutionary relationship
Examples: Fore-limbs of whales, birds, cats, and humans have similar bone structures

10. Homologous Structures

11. Analogous Structures
Structures that perform the same function but have different anatomy
This shows NO EVOLUTIONARY RELATIONSHIP
Example: The wings of birds and butterflies

12. Analogous Structures

13. 4. Fossil Record
Shows extinct species that have similar structures to those alive today
Includes hundreds of transitional fossils that demonstrate intermediate stages in evolution
Examples
Giant armadillos and sloths
Cephalopods

14. Giant Armadillo and Sloth

15. How did this whole thing happen?
Pangea
The idea that our earth was once one huge planet that split apart and became the 7 continents we know today.

16. 5. Genetic Similarities (Biochemical Homology)
Related organisms have closely related DNA sequences and amino acid sequences
This comparison tends to be more reliable than anatomical studies
Examples: Human and chimpanzee DNA are 98% similar

17. Genetic Similarities