Download Title of Lesson Natural Selection – Pepper Moth Game Subject Area

Title of Lesson
Natural Selection – Pepper Moth Game
Subject Area
Genetics
Age or Grade Level
8th
Brief Overview
Show an example of natural selection using an online game
Estimated Time
50 min
Standards/Unit Goals
Learn appropriate vocabulary, Developing models,
Essential Questions
How does the environment of organisms shape how they
look through natural selection
Skill Objective(s)
By end of this lesson, students
will be able to
Use evidence provided by a simulation to complete a
worksheet and better understand the force of natural
selection.
Knowledge Objective(s)
By end of this lesson, students
will know
Be able to define natural selection especially in the case of
pepper moth populations.
Materials Needed
Pepper moth game. Worksheet
Technology Tools Used
MacBook with flash for each student
Useful Vocabulary
Natural Selection
Allele
Population
Pepper Moth
Prerequisite knowledge/skills
Understanding of Heredity and familiar with how evolution
works
Students may confuse common ancestors with species
Anticipated Student
descendance from another species. Such as humans
Preconceptions/Misconceptions
evolving from chimpanzees
Instructional Tips/Strategies
for the Teacher
Lesson Sequence
Engage: Students to be presented with a history of the
Theory of evolution form the ancients to Darwin and finally
to Kettlewell. Trying to emphasize that thinkers from all of
the world had ideas about species and how they came about.
In my PowerPoint I focused on how each group viewed the
natural order of things (Greeks, Chinese, Middle East,
modern understanding). I like to include these different
cultures because my class is so diverse and I think that it
helps them to engage when they see that science is not only
done by old white men. However all this leads to a very old
and very white man, Charles Darwin. I tell the classic story
of his travels and the corroboration of his ideas by Alfred
Wallace. And finally Kettlewell’s experiments on Pepper
Moths (one more white guy).
The important thing to get them to grasp is that evolution is
a long term process in which a species adapts to changing
environmental conditions and can take millions of years.
However how do we know that this happens as a human life
span is only 70 years? Kettlewell’s experiment shows a
vivid and testable environment for natural selection. In short
environmental pollution changed the habitat of nearby forest
from white barked trees into soot covered bark. This change
greatly affected the Pepper moth population which were
primarily white and in a few short years the population of
moths showed a very high percentage of black moths It is
clear the black moths had the advantage and they were
‘selected’ by the environment to breed more frequently than
their white brethren
Explore: The effect of predation and camouflaging of
individual moths was adaptation that we are exploring and
using a simulation on the internet we can have groups of
kids explore natural selection using the pepper moth
example. Have students partner up to play game and record
data for each other to complete worksheet. The simulation
runs two scenarios the first is the unpolluted forest of white
tress and the second is the polluted forest of black trees. The
student using the mouse will ‘hunt’ the moths with a bird by
clicking on the moths to eat them. Although sometimes
gruesome the students soon realized the advantage of moth
coloring to their survival.
Explain: Now using the recorded data from each partners
run the students must make a CER about the effect of
pollution on the population of white moths in the forest. The
students use the data as evidence and have to use the idea of
natural selection in their reasoning.
Resources
Weblinks
Reproducible Materials
References
http://peppermoths.weebly.com/
Assessment
Claim, Evidence, Reasoning to describe natural selection as
it pertains to pepper moths in England
Extensions/Explorations
Graphing, population distributions,
Reflections
The activity was a very good one, even though some
students tried to subvert the system by eating the harder to
see moths. However even their attempts to do this was not
completely effective and these students understood the
system well enough to subvert it so I guess it was less
concerning in that respect. I found that some students were
very interested in the history portion that I presented and I
think that giving the context of science in history can be a
powerful tool for science teachers and can engage students
especially if you give some respect to a culture or person
that they can identify with. Presenting science as an
inclusive and approachable pursuit should help engage
everyone.
Contact Information
Scott Gillard [email protected]