| A | B |
| Glaciers | Huge sheets of frozen ice. |
| Ice Age | Period when Earth was covered with ice |
| Beringia | Land bridge that connected North America to Asia |
| Mammoth | Large elephant like animal that existed during the ice age |
| Maize | type of corn |
| Mound Builders | Tribe that built religious mounds, lived in the lower Mississippi river valley |
| Irrigation | Way to bring water to an area that does not normally have water |
| Civilization | complex society with govenment, religion, and education |
| Archeologist | One who studies ancient civilizations |
| Mayan | Created a calendar and the number zero |
| Anasazi | Tribe that lived near the four corners regions |
| States making up the four corners | Colorado, Arizona, New Mexico, and Utah |
| Specialize | Enabled the early tribes to start trading cities |
| Salt | Helped to preserve food. |