“The field of macroevolution embraces the excitement of seeking an understanding of the breadth of life” -Levinton

Taxonomic-based definition

1. “Evolution above the species level”2. Between species evolution (as opposed to

within species, which is microevolution)

Splitting vs. Budding

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Change in bothdescendants

Change in onedescendant

Bottleneck Effect

• Extreme form of Genetic Drift.• Entire population goes through this.

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Founders Effect

Extreme form of Genetic Drift

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Founders Effect

BONOBO DISTRIBUTION

What is Macroevolution? Macroevolutionary Questions:

• Big Question 1: How do we establish evolutionary relationships among taxa?

Specific:Who are humans’ closest relatives?

www.bushorchimp.com

Why are there still chimps?

• Science does not say we descended from modern chimps

• Does say humans and modern chimps descended from a common ancestor

• The common ancestor probably had some characteristics of both species.

Macroevolutionary QuestionsBig Question 2. What processes/factors

regulate the rates of evolutionary change?

Specific:Do mice evolve faster thanelephants?

Macroevolutionary Questions:

Specific:Why did dinosaurs become extinct?

Big Question 3: What environmental changes regulated the timing of evolutionary radiations and extinctions?

Macroevolutionary QuestionsBig Question 4. Do extinctions affect the

evolution of other groups?

Specific: Did the Extinction of dinosaursallow the radiation ofMammals?

Macroevolutionary Questions• Big Question 5 – What ecological processes

regulate diversity?

Specific: Did ecology contributeto the “Cambrian explosion”?