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The Genetic Basis of Adaptation
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Activity 12: The Genetic Basis of Adaptation
Activity 12: The Genetic Basis of Adaptation
Activity 12: The Genetic Basis of Adaptation
Get
Started

What do you predict is eventually likely to
happen to the population of mice in the
darker environment?
Activity 12: The Genetic Basis of Adaptation
Introduction
Read the introduction.

A biological adaptation, or adaptation,
is an inherited characteristic that favors
the survival or reproduction of an
organism, and is the result of natural
selection.
Activity 12: The Genetic Basis of Adaptation
Challenge

How did a change in the
environment lead to genetic
changes in populations of the
rock pocket mouse?
Activity 12: The Genetic Basis of Adaptation
Procedure

Coat color in rock pocket mice is
determined by a single gene that follows
a dominant—recessive pattern.
Activity 12: The Genetic Basis of Adaptation
Procedure



D – dark-colored coat, dominant allele
d – light-colored coat, recessive allele
Possible genotypes:
◦ DD – homozygous-dominant dark mouse
◦ Dd – heterozygous dark mouse
◦ dd – homozygous-recessive light mouse
Activity 12: The Genetic Basis of Adaptation
Procedure




Student 1: D, d
Student 2: d, d
Student 3: d, d
Student 4: d, d
Activity 12: The Genetic Basis of Adaptation
Procedure
Generation
Number of D
alleles in
parent
mouse
population
Number of d
alleles in
parent
mouse
population
Activity 12: The Genetic Basis of Adaptation
Total
number of
light-colored
offspring
mice
Total
number of
dark-colored
offspring
mice
Procedure
Return to Student Sheet 3.1, “Ideas
about Evolution”
 Add information from this activity or a
previous activity to support whether any
of the statements are correct or
incorrect.
Activity 12: The Genetic Basis of Adaptation
Follow Up


How does the final population of mice
compare to the population you began
with?
Why was genetic diversity important to
the survival of the mice in the dark
environment?
Activity 12: The Genetic Basis of Adaptation
Follow Up


How would a scientist who studies
processes such as natural selection use
models?
Is there anything you would change in the
model we used that would improve its
accuracy?
Activity 12: The Genetic Basis of Adaptation
Follow Up
Analysis 1

Explain how a change in the environment
led to selection for:
◦ a. genetic changes in the population of mice
over several generations.
◦ b. phenotypic changes in the population of
mice over several generations.
Activity 12: The Genetic Basis of Adaptation
Revisit the
Challenge

How did a change in the
environment lead to genetic
changes in populations of the
rock pocket mouse?
Activity 12: The Genetic Basis of Adaptation
Key
Vocabulary







adaptation
allele
biological adaptation
evolution
evolve
gene
genetic diversity
Activity 12: The Genetic Basis of Adaptation