Resources for Teaching and Learning about Evolution1
These Teacher Notes provide:
 Suggestions for Teaching Evolution to Students with Religious Concerns (page 1)
 Natural Selection, including major concepts, common misconceptions and recommended
learning activities (pages 1-5)
 Understanding and Analyzing the Evidence for Evolution, including recommended
learning activities and other resources (pages 5-7)
 Recommended General Resources for Teaching about Evolution (pages 6).
Learning activities that are explicitly aligned with the Next Generation Science Standards 2 are
designated (NGSS).
Suggestions for Teaching Evolution to Students with Religious Concerns
“Defusing Discomfort” (The Science Teacher, February 2017, pages 26-30) describes how to use
a reflective writing assignment to help students with religious scruples feel open to learning the
science of evolution. The author recommends that, before you begin classroom teaching about
evolution, you have students complete a private writing assignment in response to a prompt such
as:
“Before we begin our discussion on evolutionary theory, please reflect on your personal
philosophical or religious views with regards to evolutionary theory. What is the
difference between science and religion?”
These writing assignments are graded based on the thoughtfulness and thoroughness of the
student’s response, not on the student’s opinions.
An alternative approach that emphasizes classroom discussion rather than a private writing
assignment is presented in “Beyond ’Teaching the Facts’: How to Teach Evolution to Religious
Students Who Don’t ‘Believe’” (http://asutechwebs.blogspot.com/2016/05/beyond-teachingfacts-how-to-teach.html).
Natural Selection
Major Concepts
 A typical population of biological organisms produces more offspring than can survive to
reproduce.
 Different individuals in a population have different characteristics; this is variation.
 Fitness is the ability to survive and reproduce.
 A characteristic which is influenced by genes and can be inherited by a parent’s offspring is
called a heritable trait.
 A heritable trait that increases fitness is an adaptation.
 An adaptation tends to become more common in a population. Because the adaptation
increases fitness, individuals with this trait generally produce more offspring. Because the
trait is heritable, offspring generally have the same trait as their parents. Therefore, the
adaptation tends to become more common in the population. This process is called natural
selection.
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By Ingrid Waldron, Department of Biology, University of Pennsylvania, 2018. These Teacher Notes are available with
clickable links at http://serendip.brynmawr.edu/exchange/bioactivities/evolrec
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http://www.nextgenscience.org/ and
http://www.nextgenscience.org/sites/default/files/HS%20LS%20topics%20combined%206.13.13.pdf
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Another way to describe the process of natural selection is as follows. Since (1) individuals
with an adaptation are more likely to survive and reproduce and (2) parents pass their alleles
to their offspring, the allele(s) that result in an adaptation tend to become common in the
population.
Natural selection results in changes in the frequency in a population of an adaptation and the
allele(s) that result in the adaptation. Natural selection does not cause changes in an
individual.
Evolution by natural selection only occurs if there is variation in a heritable trait which
contributes to differences in fitness.
Which characteristics are adaptations depends on which type of environment the population
is in. The same population will evolve differently in different environments.
If an environmental condition changes, an adaptation that increases fitness in the new
environment will become more common in the population. If the change in the
environmental condition is reversed, the effects of natural selection will be reversed.
In biological populations, evolution by natural selection usually occurs slowly over multiple
generations.
Several Common Misconceptions3
 Individual organisms can evolve during a single lifespan.
 Natural selection involves organisms trying to adapt.
 The "needs" of organisms account for the changes in populations over time (goal-directed or
teleological interpretation).
 The fittest organisms in a population are those that are strongest, fastest, and/or largest.
Recommended Learning Activities
To introduce the major concepts and counteract common misconceptions, I recommend
"Evolution by Natural Selection" (http://serendip.brynmawr.edu/sci_edu/waldron/#evolution).
In this minds-on, hands-on activity, students develop their understanding of natural selection by
analyzing specific examples and carrying out a simulation. The questions in the first section
introduce students to the basic process of natural selection, including key concepts and
vocabulary. The second section includes a simulation activity, data analysis, and questions to
deepen students' understanding of natural selection, including the conditions that are required for
natural selection to occur. In the third section, students interpret evidence concerning natural
selection in the peppered moth and answer questions to consolidate a scientifically accurate
understanding of the process of natural selection, including the role of changes in allele
frequency. (NGSS)
To further develop student understanding of natural selection, I recommend that this introductory
activity be followed by “Evolution of Fur Color in Mice – Mutation, Environment and
Natural Selection”
(http://serendip.brynmawr.edu/exchange/bioactivities/NaturalSelectionMice). This analysis and
discussion activity reinforces student understanding of natural selection. Students view a brief
video that presents research findings concerning the roles of mutation and natural selection in the
evolution of fur color in rock pocket mice. Multiple-choice questions in the video and analysis
and discussion questions in the Student Handout guide students to a better understanding of
mutation, environment, and natural selection. Students learn how the same trait can evolve
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Most of these misconceptions are excerpted from Misconceptions about evolution, available at
http://evolution.berkeley.edu/evolibrary/misconceptions_teacherfaq.php
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independently in different populations and how analysis at multiple levels from the molecular to
the ecological contributes to a better understanding of evolution by natural selection. (NGSS)
This recommended sequence of two learning activities will help students meet the following
specific standards from Next Generation Science Standards.4
 Students will gain understanding of two Disciplinary Core Ideas:
o LS4.B Natural Selection. "Natural selection occurs only if there is both (1) variation in
the genetic information between organisms in the population and (2) variation in the
expression of that genetic information – that is, trait variation – that leads to differences
in performance among individuals. The traits that positively affect survival are more
likely to be reproduced, and thus are more common in the population."
o LS4.C Adaptation. "Natural selection leads to adaptation, that is, to a population
dominated by organisms that are anatomically, behaviorally, and physiologically well
suited to survive and reproduce in a specific environment. That is, the differential
survival and reproduction of organisms in a population that have an advantageous
heritable trait leads to an increase in the proportion of individuals in future generations
that have the trait and to a decrease in the proportion of individuals that do not.
Adaptation also means that the distribution of traits in a population can change when
conditions change."
 Students will engage in several Scientific Practices:
o Developing and Using Models: “Develop and/or use a model (including mathematical
and computational) to generate data to support explanations, predict phenomena, analyze
systems, and/or solve problems.”
o Analyzing and Interpreting Data: “Evaluate the impact of new data on a working
explanation and/or model of a proposed process or system.”
o Constructing Explanations and Designing Solutions: “Apply scientific ideas, principles,
and/or evidence to provide an explanation of phenomena and solve design problems,
taking into account possible unanticipated effects. Apply scientific reasoning, theory,
and/or models to link evidence to the claims to assess the extent to which the reasoning
and data support the explanation or conclusion.”
 These activities provide the opportunity to discuss the Crosscutting Concepts:
o Cause and effect: Mechanism and explanation – “In grades 9-12, students understand that
empirical evidence is required to differentiate between cause and correlation and to make
claims about specific causes and effects. They suggest cause and effect relationships to
explain and predict behaviors in complex natural and designed systems. They also
propose causal relationships by examining what is known about smaller scale
mechanisms within the system.”
o Systems and System Models – Students can “use models and simulations to predict the
behavior of a system, and recognize that these predictions have limited precision and
reliability due to the assumptions and approximations inherent in the models.”
o Stability and Change – “Students understand much of science deals with constructing
explanations of how things change and how they remain stable. They quantify and model
changes in systems …”
o Scale, Proportion and Quantity – “students understand the significance of a phenomenon
is dependent on the scale, proportion, and quantity at which it occurs. They recognize
patterns observable at one scale may not be observable or exist at other scales…”
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Next Generation Science Standards
(http://www.nextgenscience.org/sites/default/files/HS%20LS%20topics%20combined%206.13.13.pdf)
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These activities help to prepare students for the Performance Expectations5:
o HS-LS4-2, "Construct an explanation based on evidence that the process of evolution
primarily results from four factors: (1) the potential for a species to increase in number,
(2) the heritable genetic variation of individuals in a species due to mutation and sexual
reproduction, (3) competition for limited resources, and (4) the proliferation of those
organisms that are better able to survive and reproduce in the environment."
o HS-LS4-3, "Apply concepts of statistics and probability to support explanations that
organisms with an advantageous heritable trait tend to increase in proportion to
organisms lacking this trait."
o HS-LS4-4, "Construct an explanation based on evidence for how natural selection leads
to adaptation of populations."
Additional Recommended Learning Activities
“The Making of the Fittest: Got Lactase? The Co-Evolution of Genes and Culture”
(http://www.hhmi.org/biointeractive/making-fittest-got-lactase-co-evolution-genes-and-culture).
This includes a video about natural selection for lactase persistence and student activities,
including “Lactase Persistence: Evidence for Selection” and “Lactose Intolerance: Fact or
Fiction”. (The video is also available in Spanish.)
"Selection and the Blond Beach Mouse"
(http://sciencecases.lib.buffalo.edu/cs/collection/detail.asp?case_id=791&id=791). This case
study engages students in understanding the adaptive value of blond fur for deer mice that live in
sandy beach areas, as well as the molecular genetic mechanisms that result in blond fur. This
PowerPoint presentation incorporates multiple questions for students, including questions related
to the distinction between proximate and ultimate causes, a challenge to plan an experiment, and
questions to analyze the results of a related published experiment. For a typical high school class,
I recommend using Part I and the simplified version of Part II, and omitting Part III.
A more extensive sequence of activities for teaching students about natural selection is proposed
in "Making Sense of Natural Selection" (The Science Teacher 80 (6): 43-49, 2013) (NGSS). For
example, to familiarize students with variation in natural populations, you can use "Natural
Selection and Variation in Birds"
(http://csip.cornell.edu/Curriculum_Resources/CSIP/Ardia/default.html).
Student understanding of natural selection can be enhanced by having them apply their
understanding to analysis of additional phenomena, as presented in the following activities:
 "Using Molecular and Evolutionary Biology to Understand HIV/AIDS and Treatment"
(http://serendip.brynmawr.edu/exchange/bioactivities/HIV ) (NGSS)
 "The Origin of Species: The Beak of the Finch" a 16-minute video
(http://www.hhmi.org/biointeractive/origin-species-beak-finch) together with the
classroom activity, "Evolution in Action: Graphing and Statistics"
(http://www.hhmi.org/biointeractive/evolution-action-data-analysis) (The video can also
serve as an introduction to discussion of speciation.)
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these activities are designed for high school students, but they can be used with middle school students to help
them prepare for the Performance Expectations, MS-LS4-4, "Construct an explanation based on evidence that
describes how genetic variations of traits in a population increase some individuals' probability of surviving and
reproducing in a specific environment." and MS-LS4-6, "Use mathematical representations to support explanations
of how natural selection may lead to increases and decreases of specific traits in populations over time."
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You may also want to show the video, “Malaria and Sickle Cell Anemia”
(https://www.youtube.com/watch?v=Zsbhvl2nVNE). This video describes the research that led
to our understanding of how natural selection resulted in relatively high frequencies of the sickle
cell allele in some populations exposed to malaria.
“Evolution and Adaptations” (http://serendip.brynmawr.edu/exchange/bioactivities/evoadapt) is
an analysis and discussion activity for students who have a basic understanding of natural
selection. In common experience, the term "adapting" usually refers to changes during an
organism's lifetime. In contrast, evolutionary biologists use the term "adaptation" to refer to a
heritable trait that increases fitness. To help students reconcile these different concepts, this
activity introduces the concept of phenotypic plasticity (the ability of an organism to adapt to
different environments within its lifetime). Questions guide students in analyzing how the
balance between the advantages and disadvantages of a characteristic (e.g. an animal’s color) can
vary in different circumstances, how phenotypic plasticity can be a heritable trait that can
optimize fitness in a variable environment, and how natural selection can influence the amount
of phenotypic plasticity in a population. (NGSS)
Understanding and Analyzing the Evidence for Evolution
How could complex eyes have evolved?
(http://serendip.brynmawr.edu/exchange/bioactivities/evoleye) is an analysis and discussion. In
this activity, students analyze evidence from comparative anatomy, mathematical modeling, and
molecular biology. This evidence suggests a likely sequence of steps in the evolution of the
human eye and the octopus eye. General concepts used to interpret this evidence include natural
selection, fitness, and the difference between homology (similarity due to common descent) and
analogy (similarity due to convergent evolution). Optional additional questions presented in
these Teacher Notes can be used to discuss additional topics such as the contributions to
evolution of gene duplication and mutations in the regulatory DNA sequences that control gene
expression. (NGSS)
All in the Family (http://www.pbs.org/wgbh/evolution/change/family/ ) is a very useful online
activity to help students understand the importance of homology and similarities in development
for establishing phylogenetic relationships.
A Whale of a Tale? The Evidence for the Evolution of Whales
(http://sciencecases.lib.buffalo.edu/cs/collection/detail.asp?case_id=814&id=814) is a
PowerPoint with embedded questions. First, students study an array of whale fossils to learn how
evolution is properly viewed as a branching, relationship-based process. They learn how
scientists seek to reconstruct past relationships and study transitional features. Students then
learn that evidence for macroevolution relies on several lines of independent evidence from
fossils, comparative anatomy, embryology, genetics, and paleoecology.
Evolution in a Ring (http://www.actionbioscience.org/evolution/lessons/irwinlessons.pdf )
provides evidence and activities for students to analyze a salamander ring species in the Pacific
Coast region of the US. This activity will help students understand the process of speciation.
Cells within cells: An extraordinary claim with extraordinary evidence
(http://undsci.berkeley.edu/article/endosymbiosis_01) provides an informative review and
analysis of research on the hypothesis that mitochondria and plastids are evolutionarily
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descended from endosymbiotic bacteria. This reading can be used with the discussion activity
shown on the last page of this overview of Resources for Teaching and Learning about
Evolution.
Teaching about Evolution and the Nature of Science
(http://www.nap.edu/download.php?record_id=5787# ) is a helpful resource for learning about
the types of evidence that support our understanding of evolution, with relevant teaching
activities.
Recommended General Resources for Teaching about Evolution
Understanding Evolution (http://evolution.berkeley.edu/) provides an introduction, teaching
materials and resource library. One useful resource for planning your teaching is a compilation
of misconceptions about evolution and responses to these misconceptions
(http://evolution.berkeley.edu/evolibrary/misconceptions_faq.php). (Another useful compilation
of misconceptions and responses is available at http://www.talkorigins.org/faqs/faqmisconceptions.html.)
Evolution (http://www.pbs.org/wgbh/evolution) provides information about many important
aspects of evolution and a variety of resources for teachers and students.
HHMI BioInteractive (http://www.hhmi.org/biointeractive/evolution-collection) has many
resources for teaching evolution. For example, The Making of the Fittest
(http://www.hhmi.org/biointeractive/shortfilms/) has several short films (including The Making
of the Fittest: The Birth and Death of Genes, The Making of the Fittest: Natural Selection in
Humans) with accompanying classroom activities.
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Cells within cells: An extraordinary claim with extraordinary evidence
Read at least pages 1, 3, 6-8, 11, and 13 of "Cells within cells: An extraordinary claim with
extraordinary evidence" (http://undsci.berkeley.edu/article/endosymbiosis_01).
Questions
1. Summarize the evidence that supports the hypothesis that endosymbiosis was the process
responsible for the evolutionary origin of mitochondria and plastids (e.g. chloroplasts).
2. Why did it take such a long time for the hypothesis of endosymbiosis to gain widespread
acceptance?
3. How does this example illustrate the following general principles?
 Two important sources of scientific progress are technological advances that provide new
ways of investigating research questions and conceptual advances that provide new ways
of understanding and asking questions about natural phenomena.
 Scientists may oppose new hypotheses for reasons that are not entirely rational,
particularly reluctance to change or replace a hypothesis that their previous research has
supported.
 For scientific hypotheses, we often are not sure if the hypothesis is true or false. Instead,
scientists have a little, some, or considerable uncertainty about the validity of many
hypotheses.
4. Use this information to make this diagram of the scientific method more accurate and realistic.
(Figure from http://static.ddmcdn.com/gif/scientific-method-17.jpg)
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