If you’re interested in the discussion over whether an extraterrestrial impact wiped out the Pleistocene megafauna, check out this balanced review of the debate by David Morrison, senior scientist at the NASA Astrobiology Institute! It’s one of the best and least technical overviews of the “rise and fall” of the hypothesis that a cosmic catastrophe changed the course of North American prehistory that I have ever had the pleasure to read.
Did a Cosmic Impact Kill the Mammoths? Excerpt: “Even without considering the technical issues at stake, there are two clues that something is amiss with the YD [Younger Dryas] impact hypothesis. First is the 2006 book The Cosmic Catastrophes, which formulates the YD hypothesis within the context of castrophist pseudoscience. … Second is the absence of confirming or supporting papers by scientists who were not members of the original team.”
For the rest of the story, go to the Skeptical Inquirer’s webpage: http://www.csicop.org/si/show/did_a_cosmic_impact_kill_the_mammoths/
Brad Lepper
