1. Chapter 16.4 (Pgs. 465-473): Evidence of Evolution

2. Biogeography
Is the study of where organisms live, now and historically
Patterns in distribution of living and fossil species can show evolutionary patterns
Two patterns:
Closely related but different species live in slightly different habitats
Distantly related but similar species live in similar habitats around the world

4. Age of the Earth
Was proposed by geologists to be much older than 6000 yrs old
In 1860s, radioactivity was discovered
Used to determine age of rocks and fossils
Is 4.5 billion years old
This provided enough time for evolutionary change to occur

5. Fossils Show the record of extinct species
Show how intermediate forms connect extinct and living species

7. Anatomy and Physiology

8. Anatomy and Physiology
Can show relationships to a common ancestor
Homologous Structures
Are similar structures
Can be used for different functions
Come from a common ancestor
Analogous Structures
Are used for the same function
Are found in unrelated organisms

9. Homologous structures show how closely related organisms are

10. Anatomy and Physiology
Vestigial Structures
Are inherited from ancestors
Have lost most of their function
Embryology
Similar patterns of development show that organisms are related to a common ancestor

13. Genetics and Molecular Biology
Common Genetic Code
DNA is universal among all organisms, which indicates a common ancestor
Homologous Molecules
Enzymes, hormones, and other important molecules are similar between organisms, which indicates a common ancestor

15. Testing Natural Selection
Has been shown in Galapagos finches
They gave beaks with different sizes and shapes
Changes in the food supply creates selection pressure on beak size
Only larger seeds are available during a drought, and only birds with larger beaks can eat them
Birds with smaller beaks starve during a drought