Anthropogenic environmental change is by no means the only threat environmental managers should worry about: soil erosion, water shortages, global pollution, biodiversity loss, genetic engineering accidents and biological, chemical and nuclear weapons are but a few of the possible threats. There is a need for governments and citizens to be more aware of, and to treat seriously, the many natural threats which are currently largely ignored: large volcanic eruptions, megatsunamis, strikes by near-Earth bodies (meteorites, asteroids, comets and other heavenly bodies), geomagnetic changes, natural climate changes, extreme weather events, and many others.