According to a new study, a massive comet impact did not lead to the end of the prehistoric human culture, known as Clovis, in North America 13,000 years ago.
Researchers say that they have gathered evidence that shows that a massive comet never impacted near the site of the Clovis society, which was located in what is now known as New Mexico.
The research was led by professor Andrew Scott of the Department of Earth Sciences at Royal Holloway, who says:
“The theory has reached zombie status. Whenever we are able to show flaws and think it is dead, it reappears with new, equally unsatisfactory, arguments. Hopefully new versions of the theory will be more carefully examined before they are published.”
The Clovis culture is widely seen as one of the oldest cultures in North America, and was once thought to be the ancestors of all the indigenous cultures of North and South America. Current research, however, suggests otherwise. Soon after forming (less than 600 years), the society disappeared, which led to speculation that a major event must have quickly killed off large portions of the society.
Scott said that the research failed to find evidence of an appropriately sized impact crater from that time period, and noted that there is no evidence of any unambiguously "shocked" materials, which is a sign that often accompanies asteroid or comet impacts. Furthermore, proposed fragmentation an explosion mechanisms "do not conserve energy or momentum", a basic law of physics that must be satisfied for impact-caused climate change to have validity, say the study's authors.
The researchers argue that other explanations must be found for the disappearance of the Clovis people. The researchers did not provide any explanation regarding their disappearance. It is not clear if the researchers will launch another study aimed at following up on additional evidence presented in support of the comet theory.
Results of the study were published recently in the journal Geophysical Monograph Series.