What Is Biodiversity?

Contributor: Jay Gregorio. Lesson ID: 13357

The earth is full of life! The number of known animal and plant species is still growing. Take a peek at these diverse species on a massive scale and discover how humans interact with them!


Earth Science, Life Science

learning style
Auditory, Visual
personality style
Grade Level
Middle School (6-8), High School (9-12)
Lesson Type
Dig Deeper

Lesson Plan - Get It!

Audio: Image - Button Play
Image - Lession Started Image - Button Start

Biodiversity is such a big word.

  • What could it mean?

Think about what you ate for breakfast this morning.

  • Did you have cereal? Or maybe eggs?

Ask a classmate or a friend what they had for breakfast.

  • Was it the same thing you had?

breakfast foods

Whatever you ate, it came from the earth. The eggs were from hens. The cereal probably came from corn or wheat. If you had orange juice, it came from oranges. Maybe you even had sausage from a pig!

All the raw materials needed to support our basic needs comes from the environment in which we live. The fact that there are so many options is an important part of biodiversity.

Keep reading to discover more!

What Is Biodiversity?

In 1985, the term biodiversity was coined from a contraction of biological diversity, which means a variety of life forms.

Biodiversity encompasses many aspects of life, starting with genetic makeup to the interactions happening in the ecosystem. Although that makes it a complex field, it is not a difficult concept to understand.

Some people assume that biodiversity is about species that are starting to decline or be extinct. That is not true. Biodiversity covers all plants, animals, humans, and even those organisms we know little about such as microbes, fungi, and invertebrates.

Explore the meaning of biodiversity as you watch What is Biodiversity? from WWF International:

Image - Video

How Diverse Is Life on Earth?

By now, you probably know that all living organisms are sorted into seven classifications.

The final classification is species; however, there are can be a lot of distinct species! For example, there are between approximately 9,000 and 10,000 species of birds!


Each species has its own unique characteristics and genes. This is true of all living things.

  • So, how many species are there on Earth?

This sounds like a simple question, but it is difficult to answer. That is because it is hard to count species that are microscopic or live in difficult-to-reach areas like the deep sea.

In fact, some scientists believe it is impossible to compile a list of all species because some go extinct before they are even discovered.

The most recent data estimates that there could be around 5.3 million to 1 trillion species on Earth.

Why Is Biodiversity Important?

It supports a healthy ecosystem.

A healthy ecosystem relies on food chains and food webs. Without predator-and-prey relationships, animals starve and become extinct.

If a food supply disappears, only those species that manage to relocate and find a new food supply will thrive. The others will continue to decline in number until they are gone, forever.

It provides the basic needs of humans.

Food, medicine, and shelter are among the basic needs of humans to survive.

Our dependence on plants and animals as food keeps us healthy and alive. We create shelter out of lumber and steel. We even turn to nature in our effort to understand and prevent diseases.

It facilitates the recycling of nature.

The role of microorganisms should not be overlooked.

By breaking down all dead organic matter, they recycle the nutrients back into nature for other living organisms to use.

To learn more about why biodiversity is a necessary part of life, you can read What Is Biodiversity?, from the American Museum of Natural History, or watch Why is biodiversity so important? - Kim Preshoff, from TED-Ed:

Image - Video

As the human ecosystem continues to rise, more habits are lost, resulting in the extinction of species with nowhere to go.

While many species go extinct -- some before we even discover them -- others are able to develop new ways to survive.

Keep going in the Got It? section to evaluate what you have learned.

Image - Button Next