| A | B |
|---|
| Australopithecus | Oldest group of early humans |
| Homohabilis | They made crude, simple tools |
| Homoerectus | First humans to build fires |
| Cromagnon | They had complex tools and were modern-like humans |
| archaeologist | They dig up sites to learn about the past |
| glaciers | Sheets of ice that covered much of the world |
| Ice Age | The times when much of the world was covered with glaciers |
| migrate | To move from one area to another |
| land bridge | Land and ice that connected two continents |
| climate | The usual weather of an area |
| agriculture | The raising of crops and animals |
| nomads | People that move from place to place |
| civilization | People that live in one area. |
| irrigation | Digging trenches for water that could be used for agriculture |
