Friday, January 16th, 2014
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Finish worksheet from class
I have checked 3 homeworks including today
◦ Creating a dichotomous key
◦ Taxonomy web
◦ Today’s HW
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Do Now
◦ Take out homework
1. What biome is Tennessee in?
2. How do you know?
3. What is the ultimate goal for all living organisms?
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SWBAT describe natural selection by using
Darwin’s 5 key points.
Essential Question
 How and why do populations change over
time?
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Natural Selection
◦ Process by which individuals that are better adapted
to their environment to survive and reproduce more
successfully than less well adapted individuals.
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Over many generations, heritable, adaptable
characteristics become more common in a
population. This process is called natural
selection
There are variations within species.
Variations are when individuals of the same
species are different from others in some of
their traits.
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English naturalist
Best known for contributions to evolutionary
theory
5 points
1.
2.
3.
4.
5.
Populations have variation
Some variations are favorable
More offspring are produced than survive
Those that survive have favorable traits
A population will change over time
Apply Darwin’s 5 points to both
statements
1. The picture to the right shows
3 fully grown Giraffes. The
longer necks are selected and
passed on to future generations.
1.
2.
3.
4.
5.
Populations have variation
Some variations are favorable
More offspring are produced than survive
Those that survive have favorable traits
A population will change over time
1. Populations have variation
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Long necks vs. Short necks
2. Some variations are favorable
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Long necks are favorable because they can get more
food
3. More offspring are produced than survive
4. Those that survive have favorable traits
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The long necks will survive more often
5. A population will change over time
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Over time, the average length of the Giraffes neck
will increase because it is a favorable trait
The Canadian Lynx and the Arctic Hare have a
predator-prey relationship. The average
speed of both species has increased over a
long period of time.
1.
2.
3.
4.
5.
Populations have variation
Some variations are favorable
More offspring are produced than survive
Those that survive have favorable traits
A population will change over time
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Please work independently
You have 10-15 minutes
Be prepared to go over it and share
How and why do populations change over
time?
During a storm, several butterfly eating birds
were blown to a distant island. The island,
which previously had no birds, was filled with
butterflies of all colors. 5 years later, all of
the butterflies were either green or brown.
1. What is the process called when certain
populations are better adapted and the
others will not survive?
2. What are Darwin’s 5 key points and how
does this scenario apply to the 5 points?
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