David Quammen talks about scary new emerging diseases such as Ebola, SARS, bird flu, AIDS and where they emerge from - wildlife. Most are caused by viruses. The phenomenon when such a virus passes from wild animals into people is called spillover. Two factors account for the increasing risk of spillovers that may lead to pandemics: disruption (of diverse ecosystems) and connectivity (of the global human population).

This talk was given at a TEDx event using the TED conference format but independently organized by a local community. Learn more at http://ted.com/tedx