Biodiversity is the variety of all living things on Earth, from tiny bacteria and protozoa to flowering plants, ants, birds, fishes and elephants. Biodiversity provides the building blocks for ecosystems to provide food, clean air and water, habitat, genetic resources and multiple other natural benefits to all life.
It’s important to remember that biodiversity is a dynamic, not static, process. Scientists are racing to identify and catalog species before they go extinct. The rate of species extinctions has ebbed and flowed over the long history of life on Earth, but five major mass extinction events have already occurred.
Maintaining biodiversity is essential for our health and well-being. Scientists have linked the spread of infectious diseases with changes to biodiversity, and many medical advances—including antibiotics, vaccines and hormone therapies—have come from studying species in their natural environment.
In addition, biodiverse ecosystems are more resilient to environmental change. Forests, peatlands, grasslands, coral reefs and mangroves act as carbon sinks, storing the vast majority of Earth’s carbon. Without these critical ecosystems, climate change will be much more difficult to manage.
Biodiversity is also necessary to protect our food supply. Different species of plants and animals interact in complex ways that support ecosystem stability and the provision of food, medicine, shelter, clothing and fuel. For example, disease-resistant plants may provide protection from harmful microbes, and the interaction of predators with prey helps control populations. Finally, the diverse genetic makeup of species ensures that some individuals will carry resistance to emerging pathogens or disasters like floods or droughts.