Zoonotic diseases, illnesses that jump from animals to humans, have caused many of history's major epidemics. As humans continue to encroach on wildlife habitats, scientists have predicted increasing risks. Pathogens appear more likely to spread to human populations in environments with high biodiversity experiencing land-use changes such as deforestation, agriculture or urbanization.
"There are just so many more of us, in every environment," Kate Jones, an ecologist, explained to Scientific American. "We are going into largely undisturbed places and being exposed more and more."