Ecology Facts

Ecology [ē-'kä-lə-jē]

The study of the relationship between living and non-living things and their environment.

What is Ecology?

European ground squirrel standing in the field. Wildlife scene from nature

Ecology is the study of how living (biotic) and nonliving (abiotic) parts of the environment interact with and depend on each other. Guess you could say it's the study of life on Earth!

If you break the word ecology down, 'eco' means house, and 'logos' means to study. So, essentially we are studying about our house in the biggest sense, which is Planet Earth!

Everything is Connected!

Zebra on grassland in Africa

When scientists study the ecology of certain areas, they call those areas ecosystems. Together, the living (biotic) and nonliving (abiotic) features in an area are called an ecosystem.

The biotic, or living, things in an environment include plants, animals (this includes people), bacteria, fungi, and all other living things. The abiotic or nonliving parts of the environment include things like sunlight, the soil, the atmosphere, climate, nutrients, and water.

An ecosystem can be small, like a puddle in your backyard, with only a few organisms interacting with each other. Or it may be large, like a forest, with lots of organisms interacting. Ecologists are scientists who study the interactions within ecosystems.

The populations (groups) of specific plants and animals that live together in an ecosystem make up a community. Each species occupies a certain role or “niche” in the community. A species niche includes how a plant or animal uses living and nonliving resources. No two species in a community have exactly the same niche.

Energy and the Food Web

Photo of dry grass

One of the major activities of life in an ecosystem is finding energy. All living things in an ecosystem need energy to survive. The cycle of organisms eating and being eaten is one way that parts of the environment interact with each other. The main source of energy for life on Earth comes from the sun. Plants use light energy from the sun to make food. Organisms that use the sun to produce food are called producers. Algae, grass, trees, and vegetables are all producers.

Little fox in Taiga forest. Wild animal.

Organisms that get energy by eating other organisms are called consumers. Consumers must eat producers or other consumers for their energy. This transfer of energy creates a food chain. There are four different kinds of consumers in an ecosystem:

Most consumers and decomposers get energy from more than one kind of food. Overlapping food chains create food webs.

Web of Life

An ecosystem is a complex system with many parts, both living (biotic) and nonliving (abiotic). All parts of the system are important! If one part of the system is removed, lots of other parts can be affected.

Diagram of the food web

Just imagine a car — if you didn't fill it with oil, it would still run, but not for long! An ecosystem with a part of it missing may continue for a while but in time would start falling apart. All of the parts of the ecosystem work together.

Natural Cycles and Biomes

All ecosystems depend on natural cycles. The main cycles in an ecosystem include the water cycle, the nitrogen cycle, and the carbon cycle.

Diagrams of the water cycle, the nitrogen cycle, and the carbon cycle

There are different kinds of ecosystems. Wherever you live, you are part of a large ecosystem called a biome. Biomes cover huge areas and are characterized by their climate and the types of animals and plants that are found there.

Diagram of the different biomes on Earth

The mainland-based biome types are deserts, forests, grasslands, and tundra. View a map of the world's biomes.

Constant Change

Lightning strike on the dark cloudy sky

Ecosystems are constantly changing. Houses, shopping malls, and people often replace grasslands and forests. Earthquakes, lightning, and floods can also change ecosystems. Some changes to an ecosystem — like a species becoming extinct — may be hard to see, while others — like forest fires or volcanoes — are easier to see and understand. The study of ecology helps us understand these processes.