“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”?
