1. Chapter 6 Section 2 Evidence of Evolution

2. Does natural selection occur today? YES! Cockroaches in a building…

3. Interpreting the Evidence Fossils Patterns of early development Similar body structures

4. Fossils Fossils Organisms that lived in past were different from organisms alive today Similarities in Early Development Similarities in Early Development How are these organisms similar?

5. Similarities in Body Structure Similarities in Body Structure Scientists began to compare body structures of living species to look for clues about evolution Body structure: how its bones are arranged Fish, amphibians, reptiles, birds, and mammals all have similar structures…. VERTEBRATE

6. Homologous Structures similar body structures that related species have inherited from a common ancestor

8. Inferring Species Relationships Scientists are now able to use more than just fossils, embryos, and body structures to determine how species are related… TODAY… TODAY… DNA Protein Structure Fossils Early Development Body Structures

9. Similarities in DNA Recently, scientists have begun to compare the genes of different species The more similar the DNA sequence, the more closely related the species are elephants and elephant shrews…

10. Combining Evidence Evidence from DNA and protein structure have confirmed conclusions Dog Wolf Scientists do sometimes change their hypothesis about species relationships…

11. Branching Tree A diagram that show how scientists think different groups of organisms are related

12. How Do New Species Form? When a group of individuals remains isolated from the rest of its species long enough to evolve different traits River, Volcano, Mountain Range