How Our Health Depends on Biodiversity
Posted February 9, 2011
These days, when the Endangered Species Act is chronically underfunded, under attack by Congress, and some of our most charismatic species, such as wolves, are hanging by a legislative thread, it’s good to be reminded just how important it is to preserve the diversity of life not just for its own sake but for ours.
If you want a quick primer on all the entirely self-interested reasons we should be profoundly disturbed by the wave of extinctions now washing across the globe, look no further than the booklet How Our Health Depends on Biodiversity. Written by Harvard Medical School physicians Eric Chivian and Aaron Bernstein, the pamphlet summarizes their book Sustaining Life. Here are the authors pointing out all the medical discoveries we owe to our fellow creatures:
Some compounds from plants that have been particularly important for human medicine include: morphine from the Opium Poppy (Papaver somniferum), aspirin from the White Willow Tree (Salix alba vulgaris), and the anticoagulant coumadin from spoiled sweet clover (Melilotus species). Tropical plants such as the Madagascar, or Rosy, Periwinkle (Catharanthus roseus) have yielded vinblastine (which has revolutionized the treatment of Hodgkin’s lymphoma,
turning a disease that was once uniformly fatal into one that can now be totally cured in many patients) and vincristine (which has done the same for acute
Medicines from animals include: the ACE inhibitors (which are among the most effective medicines known for treating high blood pressure) from the Pit Viper (Bothrops jararaca), and AZT (azidothymidine) used in the treatment of HIV-AIDS, patterned after compounds made by the marine sponge Cryptotethya crypta. Microbes have given us nearly all of our antibiotics such as penicillin, as well as the cholesterol lowering statins, and rapamycin (also called sirolimus), which is used to coat arterial stents, so that the cells lining the arteries opened by the stents do not divide and re-clog them.
What other medicines disappear as animals and plants around the globe continue to go extinct? This is no idle question, nor one limited to obscure and tiny organisms. As Chivian and Bernstein point out when they discuss the polar bear:
Polar Bears don’t urinate during the several months of hibernation and yet
don’t become ill. If we cannot rid our bodies of urinary wastes for several days,
we die. If we understood how hibernating bears did this, we might be able to develop better treatments for kidney failure, that each year, in the U.S. alone, kills more than 87,000 people and costs the U.S. economy more than $35 billion. More than 1 million people around the world with kidney failure are now kept alive by renal dialysis, a number that is expected to double in the next decade.
Polar Bears become massively obese prior to entering their dens and yet do
not develop Type II diabetes, as we humans tend to do when we become obese. More than 20 million people in the U.S. today have obesity-related Type II diabetes, some 7% of the population, and a quarter of a million people die from this disease each year. It is also increasing rapidly in many other countries, with some 250 million people affected worldwide.
If we lose Polar Bears in the wild, we may lose with them the secrets they hold for our being able to treat, and possibly even prevent, osteoporosis, kidney failure, and obesity-related Type II diabetes, three human diseases that kill millions each year and cause enormous human suffering.