What is life?
Why is there life on Earth, but not on any other planets in the solar system (as far as we know…). Life on Earth occurs in a bewildering array of forms – plants, animals, fungi, protists, and bacteria, which together compose Earth’s biosphere. The biosphere is connected to the Earth System through biogeochemical cycles.
Explore the links in this section to learn more about the stuff life is made of, genetics, the diversity of living things, how they coexist in ecosystems and evolve over time, and how life survives in extreme environments.