1. Chapter 1 Section 1 The Earliest Americans

2. Focus Question:  How did Early Civilizations develop in the Americas?  The Land Bridge Theory  Other Theories  How did Early Civilizations develop in the Americas?  The Land Bridge Theory  Other Theories

3. The Land Bridge Theory  Between 10,000 and 100,000 years ago, much of the world was covered by glaciers.  A glacier is a thick sheet of ice.  As more of the world’s water froze, the level of the oceans dropped.  Areas that were covered with shallow water became dry land.  One of these areas stretched between Siberia and Alaska.  It became a bridge of land many miles wide.  The area now lies under a narrow waterway called the Bering Strait.  Between 10,000 and 100,000 years ago, much of the world was covered by glaciers.  A glacier is a thick sheet of ice.  As more of the world’s water froze, the level of the oceans dropped.  Areas that were covered with shallow water became dry land.  One of these areas stretched between Siberia and Alaska.  It became a bridge of land many miles wide.  The area now lies under a narrow waterway called the Bering Strait.

4. Other Theories  Not everyone agrees with the land- bridge theory.  Some scientists think that people may first have crossed the arctic waters by boat and traveled south along the Pacific coast.  This idea is known as the coastal- route theory.  Not everyone agrees with the land- bridge theory.  Some scientists think that people may first have crossed the arctic waters by boat and traveled south along the Pacific coast.  This idea is known as the coastal- route theory.

5. Learning to Farm  For centuries, early humans could fill their most of their needs by hunting.  Over time, large animals began to disappear.  Deprived of their food, hunters had to find a new source of food and change their way of life.  Hunters became gatherers, traveling from place to place in search of plants and small game.  For centuries, early humans could fill their most of their needs by hunting.  Over time, large animals began to disappear.  Deprived of their food, hunters had to find a new source of food and change their way of life.  Hunters became gatherers, traveling from place to place in search of plants and small game.

6. Gatherers Become Farmers  About 8000 years ago, gatherers in Mexico, began growing food plants such as squash and lima beans.  The discovering of farming transformed peoples’ lives.  Families did not have to wander in search of food.  In dry areas, farmers developed a system of irrigation.  Irrigation is a way to channel water from a river or stream to water crops.  About 8000 years ago, gatherers in Mexico, began growing food plants such as squash and lima beans.  The discovering of farming transformed peoples’ lives.  Families did not have to wander in search of food.  In dry areas, farmers developed a system of irrigation.  Irrigation is a way to channel water from a river or stream to water crops.

7. Farming continued…  Farmers also learned to raise animals such as cattle, pigs,and llamas.  Once Native Americans had more food, or a surplus (extra) of food, they could trade with each other.  Some farming communities grew into cities.  The cities became centers of government and religious life.  Farmers also learned to raise animals such as cattle, pigs,and llamas.  Once Native Americans had more food, or a surplus (extra) of food, they could trade with each other.  Some farming communities grew into cities.  The cities became centers of government and religious life.

8. Three Civilizations  Mayas  Aztecs  Incas  Mayas  Aztecs  Incas

9. Mayas  Between A.D. 250 and A.D. 900, the Mayas built cities in what is now Mexico and Central America.  Their cities included large public plazas with pyramids, temples, ball courts, and palaces.  Between A.D. 250 and A.D. 900, the Mayas built cities in what is now Mexico and Central America.  Their cities included large public plazas with pyramids, temples, ball courts, and palaces.

10. Mayan Accomplishments  The Mayas developed arts, a system of government and a written language.  Using the stars and from their study of the heavens, created the most accurate calendar known until modern times.  Disease or overpopulation may have caused their decline, but Mayan language still forms the root of more than 20 languages of Central America.  The Mayas developed arts, a system of government and a written language.  Using the stars and from their study of the heavens, created the most accurate calendar known until modern times.  Disease or overpopulation may have caused their decline, but Mayan language still forms the root of more than 20 languages of Central America.

11. Aztecs  As the Mayan civilization declined, a new one was on the rise.  The Aztecs built a great capital city, Tenochtitlan, on the site of present- day Mexico City.  It was built on a series of islands in a large lake.  The city was connected to the mainland by stone roadways.  As the Mayan civilization declined, a new one was on the rise.  The Aztecs built a great capital city, Tenochtitlan, on the site of present- day Mexico City.  It was built on a series of islands in a large lake.  The city was connected to the mainland by stone roadways.

12. Aztec Accomplishments  Farmers raised crops on floating platforms.  More than 200,000 people lived or resided in Tenochtitlan at its height, making it perhaps the largest city in the world at that time.  The center of the city was a sacred place with dozens of temples that honored the Aztec gods.  Aztecs depended on the good will of the gods in everyday life.  Farmers raised crops on floating platforms.  More than 200,000 people lived or resided in Tenochtitlan at its height, making it perhaps the largest city in the world at that time.  The center of the city was a sacred place with dozens of temples that honored the Aztec gods.  Aztecs depended on the good will of the gods in everyday life.

13. Human Sacrifice  The Aztecs believed in human sacrifice.  The Aztecs were effective but harsh rulers.  Conquered tribes were forced to send treasure, food, and prisoners to the Aztec capital.  The Aztecs also forced the people they conquered to pay high taxes.  Resentful subjects would eventually turn on the Aztecs when the empire was weak.  The Aztecs believed in human sacrifice.  The Aztecs were effective but harsh rulers.  Conquered tribes were forced to send treasure, food, and prisoners to the Aztec capital.  The Aztecs also forced the people they conquered to pay high taxes.  Resentful subjects would eventually turn on the Aztecs when the empire was weak.

14. Incas  In the 1400, the largest empire was in South America.  This huge empire stretched down the coast of South America along the Andes, across the Atacama desert, and reached the Amazon Rain Forest.  At the center of the empire was the Inca capital, Cuzco.  Cuzco was connected to other cities by a great network of roads.  It was called the finest road to be seen in the world.  In the 1400, the largest empire was in South America.  This huge empire stretched down the coast of South America along the Andes, across the Atacama desert, and reached the Amazon Rain Forest.  At the center of the empire was the Inca capital, Cuzco.  Cuzco was connected to other cities by a great network of roads.  It was called the finest road to be seen in the world.

15. Incas Accomplishments  The Incas constructed buildings of huge stones carefully shaped to fit together.  Their engineers built walls to hold soil in their fields, canals to carry water, and bridges over deep canyons.  The Incas produced fine weavings and metalwork.  Inca rulers wore gold and silver jewelry, and their palaces contained plates of gold.  The Incas constructed buildings of huge stones carefully shaped to fit together.  Their engineers built walls to hold soil in their fields, canals to carry water, and bridges over deep canyons.  The Incas produced fine weavings and metalwork.  Inca rulers wore gold and silver jewelry, and their palaces contained plates of gold.