The type of ecosystem that primarily dominates the higher elevations of the Rockies is Tundra.

Tundra is typically found above the tree line in mountainous regions, including the Rocky Mountains, where conditions are too extreme for most trees to survive. At higher elevations, the climate becomes harsher with colder temperatures, shorter growing seasons, and increased wind exposure. This leads to the development of tundra ecosystems characterized by low-growing vegetation such as mosses, lichens, and small shrubs. Tundra is typically found above the tree line in mountainous regions, including the Rocky Mountains, where conditions are too extreme for most trees to survive.