Via Miller-McCune: Keeping More Species Around May Dilute Disease Threat
Biodiversity provides humanity with many benefits, including clean air and water, climate stability and renewable natural resources.
But a groundbreaking experimental study has shown that species diversity is good for something else: It protects people from dangerous zoonotic (animal-borne) diseases.
Scientists investigating an outbreak of hantavirus among farmers in Panama's Azuero Peninsula discovered the disease was harbored in two particular rodent species that thrived in areas where tropical forest had recently been cleared for cattle pasture.
In their experiment, researchers mimicked human-caused habitat degradation by removing all the native rodent species from selected plots of land at the forest-pastureland interface except for the two hantavirus-linked species, the pygmy rice rat and the cane rat. Without competition from other species, their numbers exploded — and more of the rodents became infected with hantavirus [...]The idea that greater biodiversity might reduce disease transmission originated with British ecologist Charles Elton, who noticed that a greater diversity of plant species was accompanied by a lower rate of disease, according to Richard S. Ostfeld, a participant in the Panama study. [...]
Ostfeld says that the study has deep policy implications. "Biodiversity loss is probably at least as important as climate change in terms of overall impacts on human society," he said.
If biodiversity loss can be directly tied to an increase in human, plant and animal disease, it becomes a concrete factor to be taken into account when human development threatens natural habitat, he said.
"The next step is to try to change policy so that biodiversity loss is reduced."
A study on Panamanian rats and hantavirus suggests another and less obvious benefit to biodiversity — it may diminish the threat humans face from zoonotic diseases by diluting the reservoir of animals carrying pathogens. wikipedia.org