1. Unit Title/Grade Level
Natural Selection
9th/10th Grade
2. What do you want students to understand?
What are the fundamental understandings?
Life on Earth today is very unlike life on Earth in
the distant past because environmental pressures have "selected"
population members most fit to the changing environment.
What are the essential questions?
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Why is life on Earth so different now than when
dinosaurs lived?
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If the environment changes dramatically, what might
assure human survival?
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As we create human survival advantages, how does this
impact the survival advantage of other species?
What should students know?
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Tremendous variety exists among species members.
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Species have unlimited capacities to reproduce, but
resources in a habitat are limited.
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Some members of a species are more able to compete
for limited resources, therefore have a greater chance of survival and
reproduction.
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Those species members who survive to reproduce pass
on genes for favorable traits in that environment.
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As the environment changes, different genetic traits
may be more favorable for survival.
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What should students be able to do?
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Ask questions
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Develop models
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Conduct experiments
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Communicate understandings/results
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Analyze/interpret data
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Design solutions to problems
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Use technology and mathematics to investigate
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3. With which national content standards do
the understandings align?
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Life Science: Biological Evolution
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Unifying Concepts and Processes: Evolution and
Equilibrium
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Science as Inquiry: Abilities necessary to do
Scientific Inquiry
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Information Literacy/Technology Standards:
Access information; evaluate information; use information accurately &
creatively; participate effectively as groups to generate information.
4. What are the relevance and significance
of these fundamental understandings?
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Evolution is a major theory that accounts for the
relatedness of organisms, the diversity of life on Earth, and the role that
life has in terms of impacting the planet's physical environment. These are
central concepts in biological science.
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Since evolution is such a controversial subject it is
an ongoing part of the lay person's dialogue. It is therefore important that
students understand evolution as a theory.
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While students often understand that there is genetic
diversity among members of a species, they struggle more to understand
selection. Many people interpret evolutionary selection as Lamarkian rather
than selection among species members for inherent genetic traits that favor
survival. This requires thorough investigation of the concepts and opportunity
for students to dialogue to unearth their misconceptions.
5. What is the context for this learning?
(Prior and future understandings as well as developmental appropriateness)
Prior to this unit, students should have an
understanding of the genetic basis of diversity (through mutation and
recombination). This lays the foundation for the exploration of diversity among
members of a species. After this unit, the teacher could choose to explore the
evidence of evolution. If this is the theory, how do we know it is valid?
6. Assessment - How will you know that the
students have learned?
What summative performance assessment will be
used to determine understanding?
Given a scenario, students will apply their
understandings of natural selection to determine whether natural selection has
occurred in the description. Students will be given the option of a variety of
verbal or written performances.
What formative assessments will be used during
the unit of study to assure that students develop the knowledge and skills
required to reach understanding?
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Other performances:
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Written, oral or visual products in response to
prompts:
Given pictures of various environments in which
segments of a population are placed (isolated), students will identify which
members (with given variations) will have selective advantage and describe what
might happen given enough time in isolation.
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Student exhibits or models:
Student models of population dynamics will be assessed
against a rubric
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Student self-assessments, logs, and peer reviews:
Learning logs to record information and internalize
concepts related to natural selection
7. What are the components
(lessons/modules) of your unit and how will each component contribute to the
learning of all students?
Consider the appropriate sequence to provide
inquiry-based learning opportunities.
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Variation Everywhere: In this
activity cooperative groups select a human trait and measure that trait across
the classroom. They will determine a way in which to represent their data
graphically, and, based on that graphic representation, derive a statement
about the trait to share with the class. As each cooperative group shares their
findings, class members will use double entry journals to record findings (note
taking) and to look at similarities among the groups' findings (note making).
Finally, a whole-class discussion will focus on 1) variation among a variety of
species and 2) advantages/disadvantages of variation among members of a
species.
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Population Pressure: Students are
asked to briefly put their understandings of variation within a species
"on the back burner" as they explore population growth. They are
presented with a variety of population curves from various species. Their task
is to develop a model that explains the population cycles. They then test their
model by designing and conducting an experiment with selected species. Students
share their models with two other teams and select the model (or merger of
models) they think best explains population dynamics and submits to the teacher
(assessment). Whole class discussion of submitted models consolidates classroom
understandings of population dynamics.
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Expanding the Model: Students are
asked to add the concept of variation among members of a species to this model.
They are asked to predict how variety impacts survivorship in this model. They
then test the model through a series of traditional classroom activities on
adaptive advantage. They use these activities to test the feasibility of their
model. The "labels" of competitive advantage and natural selection
are layered into the models.
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Question of the Future: Students
develop a product that describes how their model would predict future
generations of this species. How would "competitive advantage" and
"natural selection" influence the gene pool? They are given a choice
of product: poem, mind map, skit or video commercial. In addition, students
will complete a reading assignment that overviews these concepts and discuss
their reading in small groups. In these small groups, they will summarize what
they know and questions they still have. As a whole class, their knowledge and
questions will be discussed.
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Problem of Environment: Students
will be posed with a problem. They will create a creature designed to best
survive and reproduce in a given environment. Each group will be given a
different environment. Students record in their double entry journals the
reasons for their creature design (note taking). Then groups will switch
environments and check survival advantage. As they move their creature from
environment to environment, they record their findings in their double entry
journals (note taking). Students will then be asked to individually make sense
of their findings (note making) and submit their journal responses to the
teacher. As a group, they expand their model to include their understandings
from the entire unit, and they resubmit their model to the teacher.
Adapted from work by Grant Wiggins and Jay McTighe
Copyright © 1997-2003
Career Connection to Teaching with Technology
USDOE Technology Innovation Challenge Grant
Marshall Ransom, Project Manager
All rights reserved.
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