A theory put forth by a group of 25 geo-scientists suggests that a massive comet exploded over Canada, possibly wiping out both beast and man around 12,900 years ago, and pushing the earth into another ice age.
University of South Carolina archaeologist Dr. Albert Goodyear said the theory may not be such "out-of-this-world" thinking based on his study of ancient stone-tool artifacts he and his team have excavated from the Topper dig site in Allendale, as well as ones found in Georgia, North Carolina and Virginia.
The tools, or fluted spear points, made by flaking and chipping flint, were used for hunting and made by the Clovis people, who lived 13,100 to 12,900 years ago, and from the Redstone people who emerged afterwards. The two points are distinctly different in appearance, with Redstone points more impressively long and steeple-shaped.
"I saw a tremendous drop-off of Redstone points after Clovis," said Goodyear. "When you see such a widespread decline or pattern like that, you really have to wonder whether there is a population decline to go with it."
For every Redstone point, Goodyear says, there are four or five Clovis points. His findings are leading archaeologists from across North America to reexamine their fluted points, and their inventories are yielding similar results: a widespread decline of post-Clovis points that suggests a possible widespread decline of humans.
"What is interesting is that Redstone people came after Clovis people and may have lasted as many centuries as Clovis did, probably even longer, but there are fewer of these Redstone points than Clovis ones," Goodyear said. "That is really odd, because if the Redstone culture simply came right after the Clovis culture you'd expect at least as many Redstone points as Clovis ones. We just don't see that, and the question is why, and what happened to the people who made these tools?"
Archaeologists have long known that the great beasts of the age – the wooly mammoth and mastodon – suddenly disappeared around the same time period (12,900 - 12, 800 years ), but little was known about their demise. It was thought to be the result of over-hunting by Clovis man or climate change associated with a new ice age.
The notion that a comet collided with Earth and caused these events was farfetched until recently, when the group of scientists began looking for evidence of a comet impact, which they call the Younger - Dryas Event. They turned to Goodyear and the pristine Clovis site of Topper.
In 2005, Arizona geophysicist Dr. Allen West and his team traveled to Topper in hopes of finding concentrations of iridium, an extra-terrestrial element found in comets, in the layer of Clovis-era sediment.
"They found iridium and plenty of it," said Goodyear. "The high concentrations were much higher than you would normally see in the background of the earth's crust. That tends to be an indicator of a terrestrial impact from outer space."
The researchers also found high iridium concentrations at six other Clovis sites throughout North America, as well as in and along the rims of the Carolina Bays, the elliptically shaped depressions that are home to an array of flora and fauna along South Carolina's coast.
The Younger- Dryas Event suggests that a large comet exploded above Canada, creating a storm of fiery fragments that rained over North America. The fragments could have easily killed the giant mammals of the day, as well as Clovis man.
"No one has ever had a really good explanation for the disappearance of mammoth and mastodon," Goodyear said. "The archaeological community is waking up to the Younger-Dryas Event. It doesn't prove that these Clovis people were affected by this comet, but it is consistent with the idea that something catastrophic happened to the Clovis people at the same time period."
The comet theory dominated the recent annual meetings of the American Geophysical Union held in Mexico. Goodyear's Clovis-Redstone point study and West's research on the comet were featured at the AGU meetings and by the journal, Nature. The comet will be the subject of documentaries featured on the National Geographic Channel and NOVA television late this fall and in early 2008.
Dr. Al Goodyear, who conducts research through the University of South Carolina's S.C. Institute of Anthropology and Archaeology, began excavating Clovis artifacts along the Savannah River in Allendale County in 1984. In 1998, with the hope of finding evidence of a pre-Clovis culture earlier than the accepted 13,100 years, Goodyear began a concerted digging effort on a site called Topper, located on the property of the Clariant Co.
His efforts paid off. Goodyear unearthed blades made of flint and chert that he believed to be the tools of an ice age culture back some 16,000 years or more. His findings, as well as similar ones yielded at other pre-Clovis sites in North America, sparked great change and debate in the scientific community.
Believing that if Clovis and Redstone people thrived near the banks of the Savannah River, Goodyear thought the area could haven been an ideal location for a more ancient culture. Acting on a hunch in 2004, Goodyear dug even deeper down into the Pleistocene Terrace and found more artifacts of a pre-Clovis type buried in a layer of sediment stained with charcoal deposits. Radio carbon dates of the burnt plant remains yielded dates of 50,000 years, which suggested man was in South Carolina long before the last ice age. Goodyear's finding not only captured international media attention, but it has put the archaeology field in flux, opening scientific minds to the possibility of an even earlier pre-Clovis occupation of the Americas.
Since 2004, Goodyear has continued his Clovis and pre-Clovis excavations at Topper. With support of Clariant Corp. and SCANA, plus numerous individual donors, a massive shelter and viewing deck now sit above the dig site to allow Goodyear and his team of graduate students and community volunteers to dig free from the heat and rain and to protect what may be the most significant early-man dig in America.