Biology - HOT Science Lab

Teacher
Natural Selection
(Adapted from: District Adopted – Prentice Hall Laboratory Manual)
NGSSS:
SC.912.L.15.13 Describe the conditions required for natural selection, including: overproduction
of offspring, inherited variation, and the struggle to survive, which result in differential
reproductive success. (AA)
Purpose of Lab/Activity:
To explore how the frequencies of three beak phenotypes change over several
generations in a population of birds on an island.
To explore how environmental changes can affect animal populations.
Prerequisites:
Students should be familiar with Darwin‘s Theory of Evolution by natural selection.
Students should be able to describe the process of adaptation and evolution using the
tenets of Darwin.
Students should be able to identify factors that could influence natural selection and give
examples and explanations such as climate overpopulations, mutations, and pollution.
Students understand the concepts of genetic drift, gene flow, mutation, and natural
selection.
Safety:
Be sure students inform you of allergies to nuts or other foods if you will be using that
particular food item.
Take care that students do not injure themselves or others while moving around or using
their utensil ―beaks‖.
Do not consume any food items being used in activity.
Materials (per group):
Plastic spoon, knife, or fork
Self-sealing plastic sandwich bag
Food pieces (candies, unshelled nuts, beans, etc.)
Plastic container for nest (optional)
Procedures: Day of Activity:
Before
activity:
What the teacher will do:
a. Review the rules of the island and survival criteria table or print it out.
b. Discuss the essential question: Can natural selection change the frequency
of traits in a population in only a few generations
c. Set up a particular area for the ―food‖ items and another area for ―nest‖
area.
d. Have students complete the pre-lab activity and answer the following
questions.
e. Study the graph below showing the average beak depth found in the
medium ground finch population over a period of 8 years. In which years
did the medium ground finch population have the largest average beak
Biology HSL Page 73
Curriculum and Instruction