1.9 Land Bridge Theory of Migration
AMS 2013-2014
Aim: How did the first people arrive in North America?
Objectives: Students will be able to understand the effects of the ice age on the levels of
the oceans waters, identify the Bering Strait, and understand that a land bridge between
Asia and North America existed at the Bering Strait.
Procedure:
Students will complete the Do Now and share out their answers.
News Flash Game: To introduce the unit before any reading takes place create the
following challenge game. With students in small groups of cooperative teams, produce
the following story using a world map to trace your tale.
A time long ago, on this continent (point to Asia), a group of people who followed their
food, such as bison and mammoths, roamed the area. As the people continued their
daily search for food they were slowly lead to this point (point to the Bering Strait). As
they continued to follow their food they found themselves here (point to North American
side of Bering Strait). As these people continued to follow their food they eventually
scattered themselves throughout North America. Now, here is the challenge -- you can
see that there is no land between these two continents, yet animals and people crossed
here. Your job is to tell me how the people got across, or what they walked on to get to
North America.
As the teams begin solving the challenge write the first news flash on the board,
then continue to supply news flashes until the teams can secretly report the
correct answer.
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News Flash: The animals had no boats and most people walked.
News Flash: The weather turned very cold.
News Flash: An Ice Age occurred.
News Flash: As ice bergs grew oceans shrank.
News Flash: The animals and people walked on bare ground.
Students will infer as to how they believe the first people arrived in North America.
Afterwards, there is a more clear explanation as to the effect of the ice Age and how it
enabled for people to travel to places they otherwise would not have gone.
Students can use the remainder of the period to complete the work. At the end of the
period, students can share out their answers.
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Migrate (verb) – to move from one area to another.
Ex #1): Many birds migrate south during winter, in order to keep warm and be in a place
that has enough food.
Write your own sentence using the word migrate. Make sure you use it in a way that
shows your understand the meaning of migrate.
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Nomad (noun): someone who moves from place to place; usually do in the direction of
a food supply (such as animals; or a place where certain food grows).
Ex #2): The group of nomads were running very low on food. They had to travel very far
to find some, but they finally did. They stayed where the food was for one week, and
then they moved on to find another spot.
Write your own sentence using the word nomad. Make sure you use it in a way that
shows your understand the meaning of migrate.
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Thinking Back: In our first unit for North America, we have studied:
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The Olmec
The Aztec
The Mayans
Native American Americans
1) How do you think all of these people got to North America? Where did they come
from originally? Why would they decide to settle where they did, in North America?
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Name: ______________________________________________Date______________
Where Did the First Americans Come From?
Take notes as you listen!
Newsflash #1: _______________________________________________
Newsflash #2: _______________________________________________
Newsflash #3: _______________________________________________
Newsflash #4: _______________________________________________
Newsflash #5: _______________________________________________
2) Based on the newsflashes, how do you think the nomads reach North America?
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The Land Bridge
During an Ice Age, when the
world is colder, more of the world's
water freezes into ice. So less water is
in the oceans than before. This makes
the level of the oceans lower, like the
water in your bath is lower if you let
some out.
Because the ocean level is lower,
more of the land sticks out, like your
knees in the bath.
In some places, this makes islands
where before the land had been
underwater.
In other places, this makes a long
bridge of land that connects two
different continents. During the last Ice
Age, about 12000 BC, there was a land
bridge between East Asia and North
America, leading
from Siberia to Alaska, and most
archaeologists think that some people
and dogs crossed over this land bridge and began to live in North America at
that time.
These probably weren't the first people to come from Central Asia to
North and South America - the first people may have come in an earlier Ice Age,
or they may have come by boat.
3) In your own words, how were the first people able to arrive in North America? What made this
possible? Also, why did they come?
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4) Think About It: Suppose that the land bridge that joined Asia and North America had
joined North America and Africa. How would North America and its early history be
changed because of the land bridge?
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5) Think About it Some More!: Imagine that people never crossed the land bridge during
the last Ice Age. Suppose they stayed where they were originally from and never came
to North America. Who do you think would have been the first people do arrive here?
Why would they come here? Where do you think they would have been from?
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