WLHS / Biology / Monson

Name Date Per

READING GUIDE: 16.3 - Darwin Presents His Case (p. 460-464)

Evolution by Natural Selection

1) What does the phrase “the struggle for existence” mean?

2) a. Define ADAPTATION:

b. Give 3 examples:

3) Define FITNESS:

4) In the phrase “survival of the fittest”, what does survival mean in evolutionary terms?

5) Why do organisms with greater fitness generally leave more offspring than organisms that are less fit?

6) Natural selection is a mechanism for evolution. TRUE or FALSE (circle one).

7) Complete the following explanation of natural selection (see p. 463): Natural selection occurs in any situation in which more individuals are born than can survive ( ) and there is natural heritable variation ( and ), and there is variable fitness among individuals ( ).

8) Give at least 2 reasons why the following statement is NOT true: “The goal of natural selection is to produce perfect organisms.”

a.

b.

Common Descent

9) What is “descent with modification”?

10) How did Hutton’s and Lyell’s ideas contribute to Darwin’s theory?

READING GUIDE: 16.4 – Evidence of Evolution (p. 465-473)

Biogeography

1) Define BIOGEOGRAPHY:

2) Why do distantly related species in very different places sometimes share similar traits?

The Age of Earth and Fossils

3) What were 2 potential difficulties for Darwin’s theory?

a. b.

4) According to radioactive dating, about how old is the Earth?

Comparing Anatomy and Embryology

5) How do homologous structures explain the use of the same basic structure over and over for different purposes?

6) Define the following terms:

a. ANALOGOUS STRUCTURES:

b. VESTIGIAL STRUCTURES:

7) Do you think the shell of a clam and the shell of a lobster are homologous or analogous? Explain your answer.

8) Match the structure with the correct term. Terms can be used more than once

Answer / Structures / Terms
Bat wing and mouse arm / A. Homologous structure
Reptile foot and bird foot / B. Analogous structure
Dolphin fin and fish tail / C. Vestigial structure
Eyes on a blind cave fish
Snake tongue and dog nose

9) TRUE or FALSE (circle one). In vertebrates, the same groups of embryonic cells develop in the same order and in similar patterns to produce many homologous tissues and organs.

Genetics and Molecular Biology

10) How do DNA and RNA provide molecular evidence for evolution?

11) a. What are Hox genes?

b. In vertebrates, what do Hox genes control?

c. What happens when a small change is made in the gene?

Testing Natural Selection

12) What organisms have been used to test Darwin’s theories?

13) Examine Figure 16.17 (page 472).

a. How does comparing the finches’ beaks to tools help you understand how different beak shapes can help finches?

b. Explain why you think each species of finch eats different foods.

14) What hypothesis have the Grants been testing?

15) How do the Grants’ data show that genetic variation is important in the survival of a species?