Global Biodiversity

Global Biodiversity

Biodiversity refers to the variety of living organisms within a given area.


6 - 12+


Biology, Ecology, Geography, Earth Science

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A forest is filled with all kinds of animals, plants and birds. They all live together in the same space. The same is true of the ocean. Fish and plants all live together.

An area can have few or many animals. It also can have few or many kinds of plants. The word "biodiversity" refers to the number of different kinds of living things in one area. The greater the number, the higher the biodiversity.

Biodiversity includes both plants and animals. It is measured by counting the number of species that live in a specific area. Animals or plants of the same type belong to the same species. For example, all dogs belong to the species Canis lupus. People belong to the species Homo sapiens

Importance Of Biodiversity

All species are connected. They depend on each other. Forests are homes for many animals. Animals eat plants. Bees and other bugs carry pollen from one plant to another. Pollen lets plants make new plants.

People are also part of these connections. They depend on many other kinds of living beings. For example, plants help humans by giving off oxygen. Humans need oxygen in order to breathe. Plants also provide food and shade. We use plants like cotton to make clothes. We use wood to make houses.

When biodiversity is low, all species are harmed. The connections that help living things survive get weaker. Sometimes, they are broken completely. When that happens, a species can die out. For example, koalas mainly eat eucalyptus leaves. If eucalyptus trees die out, so will koalas.

Decreasing Biodiversity

In the past hundred years, biodiversity has dropped around the world. Many species are now extinct. They have died out forever.

There are many reasons for this drop in biodiversity. The biggest is that natural habitats are being destroyed. A habitat is an area that is the best place for a certain species to survive. For example, frogs need to live around water. So, ponds are natural habitats for frogs.

Today, fields, forests and swamps are quickly disappearing. People are clearing out land to plant crops or build houses. Forests are cut for wood. Wild plants and animals are losing the places they need to live.

Pollution has also caused a drop in biodiversity. So have fishing and hunting. Another problem is global warming. The planet is getting hotter overall. Global warming is caused by humans when we burn gas and coal. The gases get stuck in the air around Earth. They keep the heat from the sun and make the planet hotter. This is changing many habitats.

Scientists and others are doing what they can to protect biodiversity. Thousands of parks have been set up around the world. They are helping to save plants and animals.

Fast Fact

Species by the Numbers
Scientists have identified about 1.75 million different species. That includes 950,000 species of insects, 270,000 species of plants, 19,000 species of fish, 9,000 species of birds, and 4,000 species of mammals. This is only a small portion of the total number of species on Earth. There are millions more species yet to be discovered and named.

Fast Fact

Medicine from Nature
About 25 percent of the medicines used today are taken from or modeled on chemicals found in plants, animals, or other living things.

Fast Fact

Powerful Pollinators
Bees, birds, and other creatures pollinate 75 percent of the world's major crops. In areas with lots of biodiversity, insects and other creatures pollinate plants naturally. But when biodiversity is reduced, this is impossible. There are not enough insects to pollinate large fields of single crops, so farmers must truck in honeybees to do the job.

California almond farmers need about 1.5 million hives of honeybees to pollinate their crops. That's more than half of all the commercial beehives in the country.

Media Credits

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Melissa McDaniel
Santani Teng
Erin Sprout
Hilary Costa
Hilary Hall
Jeff Hunt
Diane Boudreau
Tara Ramroop
Kim Rutledge
Mary Crooks, National Geographic Society
Tim Gunther
Jeannie Evers, Emdash Editing, Emdash Editing
Kara West
Educator Reviewer
Nancy Wynne
National Geographic Society
Last Updated

October 19, 2023

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