Download Objective 1

Standard 5
Big Question / Overarching Concept
What causes biological diversity?
—- Evolutionary Process
Objective 1
What is the mechanism by which evolution occurs?
---Natural Selection
Instructional Episode
Understanding Natural Selection: The concept of Fitness – Activity is attached.
Core Objectives
Relate principles of evolution to biological diversity.
 effects of environment on natural selection
 genetic variability and adaptation
 Reproductive isolation and speciation
 Selective breeding (artificial selection), Natural Selection - Agriculture
Crosscutting Concepts
Cause and Effect and Patterns
Students study the cause and effect of environment on evolution.
Students study Patterns of change over time due to natural selection
Science Practices
Analyzing and Interpreting data –
Obtaining, Evaluating and Communicating Information
Students will interpret charts and graphs that relate environmental
change to Evolution.
Students a provided with a variety of charts and graphs and have them
Interpret them first by themselves on a sheet of paper, then they
discuss their ideas with students at their table, then we share ideas as a
class.
Assessment
Group or individual presentation showing biological diversity and
explaining how evolution leads to biological diversity. Explanation must
match their pictures of biological diversity. For example, of picture of
different birds should be matched with an explanation of evolution of
birds.
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Objective 2
How do scientists know that evolution occurs?
Instructional Episode
What do these things have in common? Give each group pictures
and have them decide what the commonalities are.
Ex. Homologous structures pictures, Embryology pictures, Fossil
pictures with living organisms, molecular pictures with similar DNA
sequences
Core Objectives
Evidence that populations change over time
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fossils and geological records
Anatomical structures (homologous, vestigial)
molecular - mutation, recombination (sexual reproduction), DNA,
Crosscutting concepts
Scale and proportion, quantity as we discuss fossils, the geological
records and molecular evidence
Structure and function of anatomical structures
Science Practices
Mathematical and/or Computational Thinking – Hardy Weinberg
activity – adapted from AP Labs
Literacy strategies
*Read, research and discuss multiple perspectives on evolution. Look for similarities
and differences.
*Read and discuss the historical development of evolutionary process.
* Distinguish between observation and inference in making interpretations related to
evolution.
*Review a scientific article - Pay attention to research methods used to gather evidence
that documents the evolution of a species.
Assessment(s), formal or informal
Final paper typed addressing how do scientists know that evolution
occurs?
Objective 3
Question
What is a taxonomist and how does he do his job? – a guy that does your taxes? – a
guy that stuffs dead things?
----He classifies and organizes things based evolutionary relationships.
Instructional Episode
How do you organize your closet?
Hand each group a bucket of organisms and have them figure out ways to organize
them. I know some teachers do this with candy but I prefer to use real organisms.
that I have collected throughout my teaching experience. I have a variety of items
like spiders in bottles, plant parts, slides, mushrooms, odds and ends, sometimes I
throw in pictures of items. I do this at the beginning of this chapter before students
have learned about todays system.
Then, I tell students that all of these items have a common ancestor. They must
create a “family tree” and fill In any missing pieces with their inference on what the
missing pieces may look like.
I have thought about letting students utilize the computer lab or library to research
there “missing links” and see if they really exist. But I have not done this yet.
Core Objectives
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Classify organism based on their evolutionary Relationships
Skills – Use a classification key
Justify changes in classification schemes
Cross Cutting Concepts
Patterns, structure and function, stability and change.
Students look for evolutionary patterns based on the structure and function of the
organisms.
Students look for stability (and instability) in current evolutionary models. They
look at how those evolutionary models have changed and make predictions on how
they are yet to change based on organisms that are yet to be discovered.
Science Practices
Asking questions and defining problems.
Analyzing and evaluating data
Constructing explanations or solutions
Assessment
Students make informed, educational predictions on what we have yet to discover
and how this will change our classification scheme. They must support
Any well written and viable prediction gets added to the “class prediction book.”
These predictions must be typed, well thought out and supported.
Or
Tree of life web project
http://tolweb.org/tree/home.pages/treehouses.html
With Objective 1
Understanding Natural Selection The concept of Fitness
Step #1: Problematizing Fitness
Adapted from Evolution by Natural Selection
http://serendip.brynmawr.edu/sci_edu/waldron/pdf/NaturalSelectionProtocol.pdf.
Adapted from the University of California, Los Angeles Life Sciences 1 Demonstration Manual
Copyright 2005 by Jennifer Doherty and Dr. Ingrid Waldron, Department of Biology, University of Pennsylvania
Below are descriptions of four male African lions. Examine the data and
record your thinking about which lion biologists would consider the “fittest”.
Be prepared to explain your thinking about which is the “fittest” lion.
Name
Age at death
# of cubs
fathered
# of cubs
surviving to
adulthood
Size (length)
Other
information
George
13 years
Dwayne
16 years
Spot
12 years
Tyrone
10 years
19
25
20
20
15
14
14
19
9 feet
A fire burned
Spot’s home
territory, and he
moved his family
group to a new
area.
9 feet
10 feet
8.5 feet
George drove away
Dwayne had
more male lions
the most
trying to take over
lionesses in
his family group
his family
than the other
group.
males did.
Tyrone’s
family group
included four
lionesses.
Write down your thinking –
Sacramento Area Science Project [email protected] 1
Use the Talking Sticks Protocol to have a group conversation about which lion
is fittest.
Talking Sticks
Each person places his or her pencil/pen in the center of the group.
• Take turns making a comment about the reading by picking up your “talking stick”
and making your comment while you hold it.
• Once you are finished with your comment, set your “talking stick” in front of you
and you are not allowed to comment again until all the other group members have
had a turn (group members may pass their turn with the “talking stick”).
• After everyone in the group has had a chance to comment, repeat the process. ------------------------------------Step #2: Reading and processing information about the Fitness Concept Summary
Protocol
1. In each group, one person is chosen to keep the group on-task and all
participating.
2. Read one paragraph silently (leader makes sure all group members know
where paragraphs start and end). Each person reads silently to themselves
3.
4.
5.
6.
7.
and only when all in the group are finished with the paragraph under
consideration does the group progress to the next step.
Group discusses the content of the paragraph. All group members should
contribute.
Group comes to consensus about main idea(s).
Talk about how to write the main idea(s).
Each group member writes down the main idea(s).
Repeat steps 2 – 6 for each paragraph of the reading.
•
Evolution by Natural Selection (adapted from Biology, Miller and Levine, 2007)
Through observation Charles Darwin recognized in nature a process that operates
in a manner similar to the way artificial selection worked on farms. Darwin called
this process natural selection and explained its action in terms of several important
observations.
Darwin observed that wild animals and plants showed variations just as
domesticated animals and plants did. His field notebooks were filled with records of
height, weight, claw size, tail length, and other characteristics among members of
the same species. Darwin did not understand the reasons for these variations, but he
realized that many of them were inherited.
Darwin observed that high birthrates and a shortage of life's necessities forced
organisms into a constant “struggle for existence”, both against the environment and
against each other. Plant stems grow tall in search of sunlight; plant roots go deep in
the soil in search of water and nutrients. Animals compete for food and space in
which to build nests and raise young. But who among all the contenders wins the
struggle for existence?
Darwin knew that each individual differs from all the other members of that species.
Sometimes the differences are easy to observe; sometimes differences are subtle.
Individuals who characteristics are well suited to the environment survive.
Individuals whose characteristics are not well suited to the environment either die
or leave fewer offspring. This principle called Darwin called survival of the fittest.
Fitness: to survive and reproduce
Darwin was also impressed by the many different ways in which organisms survive
and produce offspring. He noted that most animals and plants have body parts and
behaviors that do certain things very well. The physical traits and behaviors that
enable organisms to survive and reproduce in their environment give them what
Darwin called fitness.
Darwin argued that fitness arises through a process called adaptation. Successful
adaptations enable organisms to become better suited to their environment, better
able to survive and reproduce. Darwin also used the word adaptation to describe
any inherited characteristic that increases an animal’s or plant’s fitness for survival.
Thus, the long neck and legs of a giraffe are adaptations that permit giraffes to feed
on leaves of trees. With these adaptations, giraffes can eat leaves too high for most
grazing animals to reach and thus are better able to survive and reproduce passing,
their genes on to their young.
Each time an organism reproduces, it passes copies of its genes to its offspring.
Thus, we can define evolutionary fitness as the success an organism has in passing
on its genes to the next generation. And we can define an adaptation as any
genetically controlled characteristic of an organism that increases its fitness.
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Step #3: Applying the Fitness Concept
Review the original data on the lions in light of what you learned from the dialogues
you’ve had and the reading.
Writing Prompt:
You are a wildlife biologist working in Africa. Another biologist makes the statement
that “George was the largest lion, so he had the best chance of fighting off enemies.
George must have the most evolutionary fitness.” Write a letter to your colleague
either agreeing or disagreeing with him. In your letter make sure you support your
position with evidence from the data, from text sources, and from your own
thinking.
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With objective 2
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