1. Evidence for Evolution Notes
February 16, 2019

2. Evolution Recap
All of the changes that have occurred in living things since the beginning of life on Earth

3. History of the Earth Earth forms 1st PROKARYOTES 1st EUKARYOTES
4.5 bya
Earth forms
3.5 bya
1st PROKARYOTES
2.1 bya
1st EUKARYOTES

4. MULTICELLULAR ORGANISMS!
700 million years ago…
MULTICELLULAR ORGANISMS!

5. Three important points…
Evolution occurs over MANY generations
Evolution occurs within POPULATIONS (NOT individuals)
Evolution involves genetic changes in a SPECIES
(Members of a species interbreed to produce healthy, fertile offspring)

6. I. Evidence for Evolution

7. A. Fossils 1.Provides TRANSITIONAL LINKS between species
Archaeopteryx:
links reptiles and birds
Therapsids:
mammal-like reptiles

8. NOTE: similar structure, but NOT always function!
B. Anatomical Evidence
Homologous Structures: structures that are similar because they were inherited from a COMMON ANCESTOR
NOTE: similar structure, but NOT always function!

9. B. Anatomical Evidence (cont.)
Analogous Structures: similar in function, but NOT inherited from a common ancestor
NOTE: similar FUNCTION, but not STRUCTURE

10. B. Anatomical Evidence (cont.)
Vestigial Structures: a body structure that has no function in a present day organism but was probably useful to an ancestor

11. C. Embryology Which one is human?
Development of embryos suggests a common ancestor

12. D. Biochemical Evidence
Almost all living things use the same biochemical molecules
DNA, Protein, ATP
Vast diversity came about by only slight differences in the same genes
The more closely “related” the organisms are, the more similar their DNA

13. E. Biogeographical Evidence
When we study the distribution of plants and animals on the planet, we notice:
Animals evolved differently in each of the biogeographical regions
We see evidence that as the continents drifted, organisms were separated and evolved.

14. F. Other Evidence
Mimicry and Camouflage
Antibiotic Resistance