アメリカ最初の住民を潜って探す

無数の考古学の発見により過去がより鮮明になるなか、最初にアメリカ大陸に渡った人類についてはいまだになぞが多くあります。最初の住民は大陸内部に入らず、海岸を伝って伝播したと考えるセオリーが近年有力になりつつあります。もしこの説が正しいならば、現在、当時の遺跡はアメリカ各地で水没していることになります。

今年の７月から８月に掛けてこれらの遺跡の確認、調査を行うプロジェクトが発足されました。Meadowcroft Rockshelterの発掘で有名になったJames Adovasio教授が、アメリカ国立海洋大気庁（ＮＯＡＡ）、フロリダやテキサスの大学と協力をし、調査を行うそうです。最初にエリアの深海の図を立ち上げ、もっとも遺跡発見のポテンシャルの高い部分を水中ロボットなどで探査するそうです。

James Adovasio’s latest archaeological expedition to find the first Americans will require little digging.
Still, the Mercyhurst Archaeological Institute director will have to reach depths of several hundred feet.

Adovasio plans to co-lead a two-week expedition in the Gulf of Mexico at the end of the month to look for evidence of early American Indians along the ancient coast of Florida, now about 300 feet underwater, Mercyhurst College in Erie announced Monday.

“We have these little hints … that there are potentially early sites off the coast of Florida,” said Adovasio, former chairman of the University of Pittsburgh’s anthropology department. “That is what makes this so exciting.”

Adovasio rose to fame three decades ago while excavating the Meadowcroft Rockshelter in Avella in Washington County. Radiocarbon dating showed the creekside outcropping was the site of human campsites as much as 16,000 years ago, five millennia earlier than archaeologists thought.
Before heading inland, paleo-Indians probably hugged the American coastline, congregating around freshwater rivers, Adovasio said. At the time, much of the world’s water was locked up in glaciers, causing ocean levels to be lower and exposing more of the continental shelf.

As the earth warmed and water levels rose, evidence of such settlements fell deeper and deeper below water.

“There is no question in almost all archaeological minds that the earliest examples of North American occupation are underwater,” said Dave Watters, curator and head of anthropology at the Carnegie Museum of Natural History. “There’s been a lot of discussion, but not a lot of research because you can spend a lot of time looking for something and not ever find it.”

Dredging and storms have turned up tantalizing clues — spearheads, bone tools — that such sites are just waiting to be found in the Gulf of Mexico, said C. Andrew Hemmings, a University of Texas at Austin archaeologist who is leading the expedition with Adovasio.

“These were probably very mobile hunter-gatherer folks,” Hemmings said. “So we’re looking for the tools that they made and the refuse of the plants and animals that they ate.”

The team hopes to find a freshwater spring that once was part of the Aucilla River, which flows out of Florida’s panhandle and into the Gulf. Animals would have gathered near the watering hole, making it a good place for people to find food. It is now 120 to 360 feet underwater.

The National Oceanic and Atmospheric Administration gave $100,000 to the project, which Mercyhurst matched. The University of Texas is providing equipment and staff. The University of South Florida is allowing the team to use its 105-foot research boat, Suncoaster.

Frank Cantelas, maritime archaeologist in NOAA’s office of ocean exploration and maritime research, said the project was among the highest-scoring grant proposals.

“It’s an area of underwater archaeology that’s been little-explored,” he said. “That early period of human occupation in North America is not really well understood, so there’s been a lot of emphasis on it in recent years.”

From July 30 to Aug. 12, the 12-member research crew will survey the seabed, first with tools that use sound waves to map the Gulf’s topography and then with a suitcase-sized diving robot fitted with cameras. If something interesting is found in shallower water, scuba divers might be sent to explore it.

But the real work will begin next year, if the team finds enough evidence to convince someone to fund a longer expedition.

“We’re going to work for two continuous weeks, as many hours each day as we possibly can,” Adovasio said. “If we find something, you better believe we’ll go back next year.”

引用元：http://www.pittsburghlive.com/x/pittsburghtrib/news/s_577616.html