1. Pick up note page and practice worksheet
Bell Work
Pick up note page and practice worksheet
Define the words DIVERGE and CONVERGE

2. TYPES OF EVOLUTION

3. Standards
CLE Explain how evolution contributes to the amount of biodiversity
CLE Explain how genetic variation in a population and changing environmental conditions are associated with adaptation and the emergence of new species.

4. Objectives
Differentiate between coevolution, divergent evolution, convergent evolution and a punctuated equilibrium
Recognize examples of each type of evolution in action

5. Important Vocabulary
Population: all of the same species that live in one area
Species: a group of closely related organisms with similar characteristics that are capable of interbreeding and producing fertile offspring

6. Adaptation vs. Acclimatization
Adaptation - Changes in traits in populations over time
Example: White moth population becoming a black moth population after 5 generations.
Acclimatization – individual organism changes physiologically
Example: growing thicker fur in winter

7. What are the types of evolution?
Natural selection can result in evolution occurring in 4 ways:
Coevolution
Divergent evolution
Convergent evolution
Punctuated equilibrium

8. 1. Coevolution
Coevolution—two species evolve together due to their close relationship. When one evolves, the other evolves too!
Examples: birds and flowers, or predators/prey

9. Coevolution Examples:

10. 2. Divergent Evolution
Divergent evolution—species with same ancestor that live in different environments adapt with increasingly different characteristics until they are no longer the same species
Key Point: DIFFERENT ENVIRONMENTS will lead to differences in which variations of traits are most “fit” (successful)
Example: Finches on the Galapagos Islands evolved into many different species to eat different foods.

11. Adaptive Radiation
an evolutionary pattern in which many species diverge from a single ancestral species

12. Leads to homologous structures

14. Divergent Evolution
Common Ancestor

15. 3. Convergent Evolution
Convergent evolution—species with different ancestors that live in similar environments adapt with increasingly similar characteristics
Key Point: SIMILAR ENVIRONMENTS lead to development of structures with similar functions
Example: Dolphins and sharks have very different internal structures, but both have evolved flippers because they live & compete in the sea.

16. Convergent Evolution
Leads to analogous structures

17. Convergent Evolution Example:

18. DIVERGENT: different environment
COEVOLUTION: predator/prey
CONVERGENT: same environment

19. Punctuated Equilibrium vs. Gradualism
Punctuated Equilibrium: evolution that is marked by isolated episodes of rapid speciation between long periods of little or no change.
Gradualism: speciation that occurred slowly over long periods of time; typically caused by a gradual selection of successful trait

20. Artificial Selection
Natural Selection = environment determines desirable traits
Artificial selection = humans determine desirable traits

21. What is a Phylogenetic Tree?
Shows evolutionary relationship among organisms based on genetic similarities (similar characteristics)
As you go down the tree, you go back in time to a common ancestor
Branching means new characteristics from the emergence of a new species
AKA: Cladograms

22. How do I read Cladograms?
The closer two lines are to each other, the more characteristics they share in common so the more closely related the species
The further away, the more distantly related X X
Which species is the closest related species to species B?
What does point X represent?

23. Reading a Cladogram
Which characteristic do all species share in common?
Which organism is most closely related to a lizard?
Which characteristic does a lizard have that a salamander does not?

24. Practice:
Complete types of evolution practice worksheet