The value of biodiversity is unknown, but we must conserve it

The value of biodiversity is unknown, but we must conserve it
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As 2017 draws to a close, many of us are exhausted by our burgeoning list of worries — nuclear war, terrorism, disease, poverty, inequality, disasters, human suffering. Concerns about the environment, let alone biodiversity loss, can seem comparatively minor, distant, or without urgency. Or so suggested by policy actions over the last year.

We have withdrawn from the Paris Accord, dismantled environmental regulations, opened the Arctic National Wildlife Refuge to oil exploration and extraction, shrunk public lands, and tried to gut the Endangered Species.

Such actions are emboldened by narratives from a vocal minority that fail to fully recognize interdependencies between human and non-human well-being. Instead, they acknowledge the need to protect only those species of clear and direct benefit to us. As summed up in one recent op-ed, “conservation is needed for ourselves and only ourselves.”


Why do we need to conserve biodiversity? A National Research Council report described three general reasons that individuals favor biodiversity conservation: (1) biodiversity is beneficial and useful to us, (2)”biodiversity adds beauty, pleasure, and enjoyment to our lives, and (3) non-human species have a right to exist and we are morally obliged to protect them. Each reason has merit and support, though the latter two are clearly shaped by individual experience, perspective, and ethics.

The first reason — we need it – is most often the focus of debate. Most concede that we do need certain species for food, medicines, or other products, but biodiversity writ large is not necessarily important. This position is conceptually attractive and emotionally comfortable. So for the sake of argument, let’s accept that we should only worry about conserving species upon which we depend.

Which species? Good question. The ones we know we need?

Here is the catch — we don’t know all of the species that are important to us. We don’t even know all of the species on the planet; only a small fraction of the millions to trillions of species on Earth have been described.

Human health and well-being depend upon “biological resources”, or the genes, species, and ecosystems that directly, indirectly, or potentially are used by humans. As such, a wide range of industries, including horticulture, agriculture, pharmaceuticals, cosmetics, forestry, and fisheries, explore and exploit biodiversity for social and economic value — something called bioprospecting.

The payoffs from bioprospecting are enormous and pervade nearly every aspect of our lives. Your health may depend upon one of 50 percent of top-selling prescription drugs originally developed from wild species or one 50,000 described medicinal plants, of which over two-thirds are still harvested from the wild. You can see the benefits of biodiversity on your dinner plate too. Biodiversity is the raw material for developing new or improved crop varieties, such as plants that are resistant to disease, drought, or increasing temperatures.

Use of genetic diversity between 1930-1980 allowed two-to-fourfold increases in U.S. yields of important crops like rice, barley, soybean, wheat, cotton, maize, tomato, and potato. And don’t forget that crops often depend upon other species, such as pollinators that support reproduction or microorganisms that improve soil fertility.

Even if we could name the hundreds of thousands of species from which we directly benefit, we do not, and cannot, know which species may be of future value, nor can we know the vast network of species that maintain the ecosystems upon which our “valuable species” depend. Is it wise to deny the existence of yet-undiscovered benefits?

Would we have had the foresight to conserve the fungus Penicillium notatum before Sir Alexander Fleming discovered its antibiotic properties in the 1920s? Probably not. Yet penicillin is one of the most effective life-saving drugs in the world and is estimated to have saved 200 million lives.

What about the Pacific yew, a “trash tree” that was routinely discarded by foresters? Fortunately we discovered that the yew contains taxol, a compound that kills cancer cells and is the basis for the best-selling cancer drug ever manufactured. The Pacific yew wasn’t important until it was.

The words of Donald Rumsfeld seem oddly appropriate here, “There are known knowns; there are things we know we know. We also know there are known unknowns. That is to say, there are things that we know we do not know. But there are also unknown unknowns — the ones we don’t know we don’t know.”

The value of biodiversity is not an unknown unknown; it is a known,unknown. We know that we cannot know all the ways biodiversity can benefit us. That is precisely why the need to conserve biodiversity is a known, known.

Amanda Rodewald is the Garvin professor and director of conservation science at the Cornell Lab of Ornithology, faculty in the Department of Natural Resources at Cornell University, faculty fellow at Cornell University's Atkinson Center for a Sustainable Future, and Public Voices fellow. Views expressed in her column are hers alone and do not represent those of these institutions.