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

TYPES OF EVOLUTION

Standards CLE 3210.5.5 Explain how evolution contributes to the amount of biodiversity CLE 3210.5.3 Explain how genetic variation in a population and changing environmental conditions are associated with adaptation and the emergence of new species.

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

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

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

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

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

Coevolution Examples:

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.

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

Leads to homologous structures

Divergent Evolution Common Ancestor

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.

Convergent Evolution Leads to analogous structures

Convergent Evolution Example:

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

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

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

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

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?

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?

Practice: Complete types of evolution practice worksheet