Chapter 15

Darwin’s Theory of Evolution

Student notes

15-1 Homework

• Define each vocabulary word in at least 1 complete sentence.

• Write out all key concepts.

15-1 The Puzzle of Life’s Diversity

Objective:

• Describe the pattern Darwin observed among organisms of the Galapagos Islands

• Who was Charles Darwin?

• What time did he live in and where did he live?

• What was his great contribution to science?

15–1 The Puzzle of Life’s DiversityA. Voyage of the Beagle

Figure 15–1 Darwin’s Voyage

B. Darwin’s Observations1. Patterns of Diversity

2. Living Organisms and Fossils

3. The Galapagos Islands

Pinta IslandIntermediate shell

Pinta

Isabela IslandDome-shaped shell

Hood IslandSaddle-backed shell

HoodFloreana

Santa Fe

Santa Cruz

James

Marchena

Fernandina

Isabela

Tower

Giant Tortoises of the Galápagos Islands

Section 15-1

C. The Journey Home• collection of fossils and species found on

mainland and the islands

• observations of the characteristics similarities and differences

• Was there a common ancestor?

• What did his travels reveal to him?

• What were the differences of species from the mainland verse those found on the island?

15–1 Homework

Answer all question in section assessment on page 372 in at least 3 complete sentences.

15–2 Ideas That Shaped Darwin’s Thinking

Objective:• How did Hutton and Lyell describe geological

change

• Identify how Lamark thought species evolved

• Describe Malthus’s theory of population growth

15–2 Ideas That Shaped Darwin’s Thinking

At Darwin’s time most believed:

*How old is the earth?

*What is the evidence for both theories?

15-2 Homework• Write out all key concepts.

• Define each vocabulary words in at least 1 complete sentence.

A. An Ancient, Changing Earth– Hutton and Lyell helped scientists

1. Hutton’s Theory of Geological Change• 1795 geologist, theory that geological

forces that have shaped earth

2. Darwin received a copy of geologist Charles Lyell’s book

Sea level

Sedimentary rocks form in horizontal layers.

When part of Earth’s crust is compressed, a bend in a rock forms, tilting the rock layers.

As the surface erodes due to water, wind, waves, or glaciers, the older rock surface is exposed.

New sediment is then deposited above the exposed older rock surface.

Movement of Earth’s CrustSection 15-2

Sea level

B. Jean-Baptiste Lamarck preceded Darwin

1. Tendency Toward Perfection

2. Use and Disuse

3. Inheritance of Acquired Traits

4. Evaluating Lamarck’s Theory

When Is a Flipper a Wing?

All living things are related. Some relationships are easy to see— your pet cat may not roar like a lion, but it clearly resembles one.

Other relationships are less obvious.

15–3 Darwin Presents His CaseObjective:• List the events leading to Darwin’s publication

of On the Origin of Species

• Describe how natural variation is used in artificial selection

• Explain how natural selection is related to species’ fitness

• State Darwin’s theory of evolution by natural selection.

15–3 Homework:

• Write out all key concepts.

• Define each vocabulary words in at least one complete sentence.

15–3 Darwin Presents His CaseA. Publication of On the Origin of

Species

B. Natural Variation and Artificial Selection

C. Evolution by Natural Selection

1. The Struggle for Existence

2. Survival of the Fittest

3. Descent With Modification

D. Evidence of Evolution1. The Fossil Record

2. Geographic Distribution of Living Species

3. Homologous Body Structures

4. Similarities in Early Development

1. The Fossil Record

2. Geographic Distribution of Living Species

3. Homologous Body Structures

Turtle Alligator

Bird Mammals

Typical primitive fish

Figure 15–15 Homologous Body Structures

Section 15-3

4. Similarities in Early Development

E. Summary of Darwin’s Theory

Concept MapSection 15-3

includes

Evidence of Evolution

Physical remains of organisms

Common ancestral species

Similar genes Similar genes

which is composed of which indicates which implies which implies

The fossil record

Geographic distribution of living species

Homologous body structures

Similaritiesin early

development

Section 15-3 Homework:

Answer all assessment question on page 386 in at least 3 complete sentences.

Chapter 15 Summary Questions

Homework:Answer all assessment question on page 389 #1-

10 in at least 3 complete sentences.