In preparing the public for a disaster, officials want to make the right call, but they also want to avoid blame. Win McNamee/Getty Images hide caption

itoggle caption Win McNamee/Getty Images

"Can something be called chicken or pork if it was born in a flask and produced in a vat?" asks Michael Spector. "Questions like that have rarely been asked and have never been answered." iStockphoto.com hide caption

itoggle caption iStockphoto.com

The New Madrid earthquakes broke up rock like this section of rock face, which was later filled with sand. This photo, from Mississippi County, Mo., was taken in 1904. M.L. Fuller (Image 336)/USGS hide caption

itoggle caption M.L. Fuller (Image 336)/USGS