The Earth is composed of many systems, which cycle and interact in both space and time. It is also part of a multitude of systems, nested in larger systems such as the solar system and the universe. Systems are composed of an untold number of interacting parts that follow simple rules; they can and do evolve. For example:

Outlining the geologic history of any region demonstrates the concept of the Earth as a system of systems. Plate tectonics drives the formation of mountains. Subsequent weathering and erosion of the uplifted mountains leads to the formation of deltas in adjacent shallow seas. And with uplifted continents, shorelines change and the distribution of marine communities are altered.

The planet’s systems are intimately connected: the forces of one system affect other systems nested within it. As plates collide, systems that drive plate tectonics are obviously linked to the formation of mountains, but they are ultimately linked to and influence much smaller systems and a wide range of landscape types, not just mountains. Much of the terrain in the Southwestern US is rugged and mountainous, reflective of relatively recent tectonic forces at work. Mountains and plateaus rise and fall; rifts open; and basins form. These forces have also driven movement of Earth’s tectonic plates, such that the Southwestern US sits between 30° and 40° North latitude.

Inland from the Pacific Ocean, the climate is largely arid, producing vast desert landscapes. The interplay of climate, rock, and water has shaped every natural landscape on the planet. Humans and other living things build upon (or tear down) the foundations lain down by these other systems, furthering their interplay.