| Era | Time
Millions of Yrs Ago Began — Ended |
Major Geological Events | Major Biological Events | Canadian Landforms Created |
| Precambrian
(earliest life) |
4600 570 |
– volcanoes erupted, many cycles of mountain building and erosion | – 1st single-celled organisms
– 1st multi-celled organisms |
– Canadian Shield formed |
|
Paleozoic (ancient life) |
570 245 | – periods when large parts of North America were covered by shallow seas | – 1st insects
– Age of Amphibians and Fish – large swamps – 1st plants & animals appear on land |
– Appalachian Mountains formed |
|
Mesozoic (middle life) |
245 66 | – shallow seas in interior of North America at times | – Age of Reptiles (dinosaurs)
– 1st flowering plants – 1st birds and mammals |
– Formation of Rocky Mountains begins
– Innuitian Mountains formed |
|
Cenozoic (recent life) |
66 present | – ice sheets covered much of North America
– continents take on present shape |
– human beings develop
– Age of Mammals – modern forms of life evolved |
– Formation of Rocky Mountains completed |
