The body of Richard III has been found beneath a parking lot in Leicester, England, according to experts from the University of Leicester. DNA testing was used to match the infamous king with DNA from a descendant of his sister. What’s the shelf life of DNA?

About a month to a million years, theoretically. The decay rate of DNA depends on the conditions of its storage and packaging. Above all, it depends on whether the DNA is exposed to heat, water, sunlight, and oxygen. If a body is left out in the sun and rain, its DNA will be useful for testing for only a few weeks.