Teatown member Margaret Lloyd recently reminded me, “It is all about the connections!” She should know, it was Margaret’s uncle, John Storer, who in his 1953 book The Web of Life made the case for how all living things from bacteria to people fit into a pattern of life that depend upon each other and the physical world around them for their existence. Yet, more than 50 years after the book’s publication, most people still don’t get it: people are connected to the physical and natural systems that makes life on Earth possible. We are intimately linked to all nature’s species and our summed actions matter by affecting the whole.
Environmental educators in recent decades answered the question of why biodiversity is important to humans by discussing quality of life issues like scenic beauty and outdoor recreation. Since the 1970’s, conservation biologists similarly focused on creating new parks for our enjoyment and saving charismatic endangered species like Bald Eagles and Florida Manatees. These are certainly worthy endeavors, but in recent years a shift has occurred among scientists and a few policy analysts as to why we should value other species and protect them.
Scientists now understand that biodiversity is key to human well-being for its role in ecosystems and its essential links to human health. An ecosystem is a network of biodiversity and non-living elements that interact to produce benefits essential for the on-going workings of the system. These benefits are called “ecosystem services.” Earth consists of a mosaic of ecosystems – e.g. forests, grasslands, wetlands, streams, estuaries, and oceans – whose services provide materials and processes that sustain life. Ecosystem services can be divided into four categories: provisioning services, regulating services, supporting services, and cultural services. It is these services that enable our communities and economies to prosper, and provide the foundation for our well-being.
Ecosystem Services (adapted from Chivian, E. and Bernstein, A. 2008. Sustaining Life: How Human Health Depends on Biodiversity. Oxford University Press, New York).
The economic value of ecosystem services is greatly underappreciate. A 2008 study commissioned by the European Union concluded that the global economy is losing more money from the disappearance of forests than from the banking crisis. The annual cost of forest loss is between $2 trillion and $5 trillion! This calculation comes from adding the value of forest services such as providing clean water, preventing soil erosion, and absorbing carbon dioxide. The point is that as forests decline nature stops providing services, and the human economy either has to provide them at great cost or do without.
In the last two decades, ecologists and physicians working together have discovered a strong relationship between healthy ecosystems and healthy people. Especially important are recent discoveries that reveal how biodiversity helps moderate or prevent infectious disease outbreaks. Lyme’s Disease, for example, is reduced in areas that have a high diversity of small mammals. This association is called the “biodiversity dilution effect” – as the disease causing organism is diluting by being spread among a diversity of small mammal species. It also is worth remembering that many medicines come from nature, and that biomedical research depends on many kinds of animals and microbes, a number of which regrettably are threatened with extinction.
The take home lesson is that it is clear that our health and human well-being depends on biodiversity and functioning ecosystems. Do you know of other connections between biodiversity and human well-being? If so, post a comment!