Evidence for Evolution (PowerPoint) Northeast 2011

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Group 2: Evolution
Fordham University:
Rose Carlson
Evon Hekkala
Gerard Iwantsch
Yale University:
Tiffany Tsang
Andy Phillips
Facilitators: Marvin O’Neal III and Carl Hashimoto
Evolution teaching tidbit
1
1
2
2
3
Who? How many?
Introductory biology for majors (freshmen). 60-75 students.
Background?
Co-requisites of chemistry and calculus.
Some understanding/knowledge of nomenclature from high school
biology (expected to vary among students).
Framework of Teachable Unit (Evidence for evolution)
1-2 hours of class time
Core Terminologies, Concepts, History
Teaching Tidbit
Concluding
Remarks
Framework
Learning Goals for the teaching unit :
In this unit, students will:
1. Understand that variation exists within a population.
2. Understand the concept of selection.
3. Understand that organisms evolve over multiple
generations (i.e. time).
4. Be able to evaluate evidence for evolution.
5. Dispel the misconception that individuals evolve.
GOAL: Understand that natural selection acts on
existing variation in a population.
Learning Objectives:
1. Be able to construct a concept map using the
terms evolution, variation, time, selection, and
reproduction.
2. Be able to identify and then describe the
steps that one would take to domesticate a
wild species.
Do Individuals Evolve?
Use your clickers to choose
one answer:
A = Yes
B = No
The idea that an individual changes in response
to natural selection is a common misconception
in evolutionary biology.
short-necked
individual
Lamarck
stretches its neck
and passes this
change on to its
offspring
long-necked
individuals
lots of time
The idea that an individual changes in response
to natural selection is a common misconception
in evolutionary biology.
short-necked
individual
stretches its neck
and passes this
change on to its
offspring
long-necked
individuals
lots of time
Lamarck
lots of time
natural selection
favors longer
necks
Darwin
original population showing
variation in neck length
descendent
population with,
on average,
longer necks
How did we get a Maltese from a wolf?
Trivial Pursuit factoid: this only took about 15000 years…
Artificial selection
intentional breeding (by humans) of animals or
plants for certain traits.
Artificial selection: wolves to many breeds of dogs.
wolf ancestor
Artificial selection: Brassica to broccoli.
Activity (5 minutes)
• Construct a concept map with a partner using
the following terms: time, evolution,
reproduction, variation, and selection.
Remember how to draw a concept map?
One possible concept map…
selection
on
variation
+/-
reproduction
evolution/
Δ variation
time
Domestication
a process by which a population of organisms
becomes
adapted to the captive environment,
occurring over generations
artificial selection is the selective force in domestication
Which of these images is an example
of domestication? (Use your clickers to
select one answer).
A.
B.
C.
D.
From wild foxes to domesticated foxes
in 30 generations flat!
• Describe how the Russian scientists domesticated
the foxes.
THINK (for 1 minute)
From wild foxes to domesticated foxes
in 30 generations flat!
• Describe how the Russian scientists domesticated
the foxes.
THINK (for 1 minute)
PAIR, and SHARE
REVIEW: the key elements required
for domestication.
• A population with existing (heritable) variation
• A human-induced selective force
• Multiple generations (i.e. time)
Natural vs. artificial selection
• The two types of selection are similar.
• However, artificial selection works much more
quickly because the selective forces are
stronger and the changes tend to be
directional
Homework:
Based on today’s material, think
about which features of a species
might make it easier or more
difficult to domesticate.
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