Biodiversity > What is Biodiversity?

Healthy ecosystems need a healthy balance of living things. For example, plants need sunlight, rain, and healthy soil full of nutrients. Insects like bees and ants feed on plants. They also help the plants make seeds by bringing pollen from flower to flower. Animals like deer, rabbits, and grasshoppers eat the plants too. And their poop returns nutrients to the soil, making it a healthy place for plants to grow.

But if there were too many hungry animals, they would eat up all the plants! Fortunately, carnivorous animals like snakes, foxes, jaguars, and even some insects keep the plant eaters in check by eating them.

Our world is like a web made up of many strands, all connected together. Break one connection, and the whole web may change!

We get a lot of benefits from species and ecosystems. They:

And biodiversity makes us happy! Who doesn’t feel better after listening to birds sing, going for a walk on the beach, or planting vegetables in a garden? Nature’s diversity makes us write poems, draw pictures, run around, stay healthy, and make new friends!

Huge dinosaurs like T. rex and thousands of other animals were part of a mass extinction about 65 million years ago. There's nothing unusual or unnatural about extinction . It's part of life's history. There have been at least five mass extinctions in the past. Today, we are in another period of mass extinction, mostly because of human activities.

Scientists have identified around 1.75 million species on  Earth . But there are millions still unidentified, and many are disappearing every day. After they’re gone, we will never know what we’ve lost. Did some of the vanished species hold ingredients we could use for medical cures? Did some provide homes or food for other species, which may starve without them? We're only beginning to understand how complicated all living relationships are!

More and more people wanting more and more stuff has a BIG effect on  biodiversity . The human population is growing very fast. We use up valuable resources, like wood and other plants and fish and other animals, faster than they can be replaced.

Habitats  are lost as we take over land for homes, factories, and farms. We overuse pesticides and fertilizers, polluting our rivers, lakes, and oceans. As we move around, we disturb the balance of ecosystems and we introduce  species  from other places. Some, like gypsy moths, kudzu, and zebra mussels, push out native species.

Laws like the Endangered  Species Act in the U.S. protect animals and plants that are in danger of becoming extinct .

Ecosystems are interconnected, so any change in an ecosystem can cause a chain of reactions. But biodiversity can help! An ecosystem with a lot of biodiversity is more resistant to a disturbance, such as a disease or a dramatic event like a fire or an earthquake. If a population of organisms has enough variety, a few individuals might have the right genes to fight a disease. If there are enough different kinds of species present, a few might have the right characteristics to survive in a colder, hotter, wetter, or drier environment. Therefore, scientists and other people work together to restore ecosystems where biodiversity has been lost.

Get involved! You can do a lot to help conserve biodiversity.