The Importance of Wildlife and the Diversity of Life

Biological diversity is critical to human welfare

What is the diversity of life? Biological diversity, or "biodiversity" for short, refers to the vast variety of wild plants, animals, fungi and microrganisms that live on our planet. Unfortunately, because we lack the vast resources that would be required to exhaustively survey every nook and cranny on the globe, scientists don't know exactly how many species exist beyond the 1.5 million already named and described. Most estimates of the number of species range anywhere between 5 to 30 million.

We also cannot say precisely how quickly we're losing biodiversity. The rate of species extinction most often given by scientists is about 1,000 times the "background rate" of extinctions that would occur without human influence. We do know that both human health and the well-being of our planet depend on biodiversity, and so a shrinking biodiversity has the potential for severe consequences.

Why biological diversity matters

Biodiversity can -- and should -- be thought of as more than a number. It's a pharmacy that provides us with essential medicines, and a supermarket that is the ultimate source of all our food stocks. It's also a library that inspires and informs designers and engineers, and a source of recreation for millions of people who fish, hunt, bird-watch or enjoy nature in other ways.

More than 40,000 species of plants, animals, fungi and microscopic animals are used in some way to benefit humans, according to a study by the American Association for the Advancement of Science. More than a third of our pharmaceuticals originated with wild plants, from common drugs like aspirin to life-saving medicines like Vincristin, which has greatly reduced childhood leukemia deaths. With most wild species not yet tested, more medicinal discoveries await us.

The use of wild plant stocks for human food sources is a subject of ongoing agricultural research. As well as developing new food products for expanding human populations, agricultural scientists turn to wild plants for resistant strains when disease strikes our crops.

Benefits: from household products to technological innovation

Industry also benefits from wild plants and animals. We use glues, lubricants, solvents and perfumes made manufactured from chemicals that originated in nature. Engineers also turn to life forms for inspiration: the Navy funded a study and prototype for a submarine that is modeled on fish movement, and the brain circuits of tiny worms known as nematodes was the model for an electronic robot the Navy developed to detect land mines at sea.

Another crucial component of biodiversity is what scientists call "ecosystem services." Forested watersheds provide clean drinking water. Wetlands filter pollutants, offering a natural water purification service. Trees also reduce pollutants, improving air quality. In a process known as nitrogen fixation, microrganisms that live only on certain plants convert atmospheric nitrogen into the form that is essential for the growth of all living plants and animals.

Other benefits of biodiversity can't be measured in dollars or otherwise quantified. Biological diversity enriches our lives by making the world an immeasurably more beautiful and interesting place to live. When plants and animals vanish, we lose something irreplaceable.

Why are we losing biodiversity?

The major cause of species loss in the U.S. and worldwide is the loss and degradation of habitat. As forests, wetlands, prairies, coastal estuaries and other habitats are converted to residential, commercial or agricultural use and other types of development, wild plants and animals vanish. In addition, many areas known as "hotspots" for their unusually rich biodiversity, such as Florida and Southern California, also have rapidly expanding human populations, which accelerates the loss of biodiversity.

In the U.S. non-native species are the second largest cause of species loss. Hundreds of Hawaii's unique wildlife and plants are being driven to extinction by non-native plants and animals. Other factors are pollution, disease, over-fishing and over-hunting.

The renowned scientist and Harvard Professor E.O. Wilson has studied and written about biodiversity for decades. He tells us: "The worst thing that can happen will happen is not energy depletion, economic collapse, limited nuclear war, or conquest by a totalitarian government.  As terrible as these catastrophes will be for us, they can be repaired within a few generations.  The one process ongoing . . . that will take millions of years to correct is the loss of genetic and species diversity by the destruction of natural habitats.  This is the folly our descendants are least likely to forgive us."

Posted: 04-May-2006; Updated: 04-May-2006