The levels of ecological organization, from smallest to largest, are typically arranged as follows:
- Individual - A single organism of a particular species.
- Population - A group of individuals of the same species living in a specific area.
- Community - All the different populations of various species that live in the same area and interact with each other.
- Ecosystem - A community along with its physical environment (including abiotic factors like soil, water, and climate).
- Biome - A larger geographical region that encompasses multiple ecosystems with similar climate and characteristics.
- Biosphere - The global sum of all ecosystems; the zone of life on Earth, encompassing all living organisms and their relationships with the environment.
So the order from smallest to largest is: Individual → Population → Community → Ecosystem → Biome → Biosphere.