1. Chapter 7 Sections 3 & 5 Evolution of Species Branching Trees

2. Why are there so many species of plants and animals? Different environmentsSpecies have evolved to live in particular habitats.

3. Genetic Diversity Organisms within the same species do not all have identical traits. All of the genetic variations make up the “gene pool”

4. How New Species Form:Geographic isolation – when some members of a species get cut off from the others Table Talk: How does the Colorado River affect squirrel species?

5. Quickwrite: Summarize how new species form.

6. How animals become extinct A change occurs in the species environment – Climate change is the leading cause The species is unable to adapt and reproduce Extinct = no members of that species are still alive – Dodo – Tasmanian Tiger – Passenger Pigeon – Dinosaurs

7. Branching Tree DiagramShows probable evolutionary relationships among organisms The base is a common ancestor for all organisms in the diagram Characteristics that appear lower on the tree developed before those higher on the tree

8. TEST YOUR UNDERSTANDING According to this tree, fish are a common ancestor of what other species? Are arachnids (spiders) related to brachiopods?

9. A More Complex Evolutionary Tree! end