"And it may be supposed to result in the greatest changes to the human beings who are the inhabitants of the world at the time. ... And animals, as we know, survive with difficulty great and serious changes of many different kinds when they come upon them at once. ... Hence there necessarily occurs a great destruction of them, which extends also to-the life of man; few survivors of the race are left, and those who remain become the subjects of several novel and remarkable phenomena ...." -- Plato, philosopher, The Statesman, 360 B.C.
"Our research indicates that the entire Great Lakes region (and beyond) was subjected to particle bombardment and a catastrophic nuclear irradiation ...." -- Richard B. Firestone, chemist, March 2001
Firestone, R.B., and Topping, W., Terrestrial Evidence of a Nuclear Catastrophe in Paleoindian Times, The Mammoth Trumpet, Volume 16, Number 2, Pages 9-16, Mar 2001
The enormous energy released by the catastrophe at 12,500 yr B.P. could have heated the atmosphere to over 1000°C over Michigan, and the neutron flux at more northern locations would have melted considerable glacial ice. Radiation effects on plants and animals exposed to the cosmic rays would have been lethal, comparable to being irradiated in a 5-megawatt reactor more than 100 seconds.
The overall pattern of the catastrophe matches the pattern of mass extinction before Holocene times. The Western Hemisphere was more affected than the Eastern, North America more than South America, and eastern North America more than western North America. Extinction in the Great Lakes area was more rapid and pronounced than elsewhere. Larger animals were more affected than smaller ones, a pattern that conforms to the expectation that radiation exposure affects large bodies more than smaller ones. Sharp fluctuations of 14 C in the Icelandic marine sediments at each geomagnetic excursion are interesting; because global carbon deposits in the ocean sediments at a rate of only about 0.0005 percent a year, a sudden increase in sediment 14 C may reflect the rapid die-off of organisms that incorporated radiocarbon shortly after bombardment.
Massive radiation would be expected to cause major mutations in plant life. Maize probably evolved by macro-mutation at that time [except that it's 80,000 years old], and plant domestication of possibly mutated forms appears worldwide after the Late Glacial period. For example, there was a rapid transition from wild to domesticated grains in the Near East after the catastrophe. ...
Much of what we assume about the Paleoindian period and the peopling of the Americas has been inferred from conventional radiocarbon chronology, which often conflicts with archaeological evidence. This work mandates that conventional radio-carbon dates be reinterpreted in light of hard terrestrial evidence of exposure of the radiocarbon samples to a cosmological catastrophe that affected vast areas of North America and beyond. A nuclear catastrophe can reset a group of unrelated artifacts to a common younger date, creating gaps and false episodes in the fossil record.