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Online Course for Teachers: Teaching Evolution

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SESSION 4

SESSION 4: What Are the Processes for Evolution?

Elaborate Part D: Coevolution

Over time, the evolution of a given species in a habitat is affected by the evolution of other species that it interacts with in that habitat.

Image of E.O. Wilson.

For further information on this phenomenon, known as coevolution, listen to the Evolution Show Four interview with E.O. Wilson, about the world of microbes.

E.O. Wilson:
The World of Microbes

Listen with:
QuickTime | RealPlayer

Then review the Evolution Show Four video segment "Ancient Farmers of the Amazon" and consider these questions:

• 

What are the four organisms involved in this system?

• 

What are the selective pressures operating on each organism in this example?

• 

How do you think natural selection has influenced the adaptations in each organism?

• 

What are some other examples of coevolution in nature?

 Image of a leafcutter ant.

Ancient Farmers
of the Amazon

View in:
QuickTime | RealPlayer

Screen grab of the Coral Reef Connections Web activity showing an underwater scene.

The Great Barrier Reef of Australia is a maze of small islands with some 3,000 individual reefs that support an incredible variety of species: 500 species of seaweeds and corals, 1,500 fish species, 4,000 mollusc species, and 240 bird species. Dive into the Coral Reef Connections Web activity to explore other examples of coevolution and the significance of biodiversity.

Now think about:

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What are some examples of coevolution in the coral reefs?

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How does evolution create biodiversity?

• 

What is the evolutionary significance of biodiversity?

Coral Reef Connections
(Flash)
Low-Bandwidth Version

Next: Evaluate Part A: Revisit Natural Selection

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