When humans first trekked from Asia to North America, perhaps as long as 25,000 years ago, the continent was gripped by ice sheets and glaciers. Those hardy immigrants probably traveled by boat or along the shore, where finding food and shelter would have been easier. The trouble for archaeologists is that as the ice melted, the seas rose and covered any traces of this early migration. Now marine geologists and archaeologists are hunting for underwater clues in the Gulf of Mexico.
This morning, a research expedition steamed out of the Port of Galveston, Texas, for the Flower Garden Banks National Marine Sanctuary, about 180 kilometers off the coast of Texas and Louisiana. Led by Robert Ballard, president of the Institute for Exploration at Mystic Aquarium in Mystic, Connecticut, and Kevin McBride of the Mashantucket Pequot Museum and Research Center in Connecticut, the expedition consists of a 44-meter-long Navy research submarine, two ships, and a remotely operated vehicle (ROV).
The submarine and ROV will survey the bottom of the reef, 120 meters deep, which is thought to have been the location of the shoreline some 20,000 years ago. The reef is built atop large reserves of salt, and Ballard says it's possible that Native Americans would have mined it from caves or tunnels. "We're confident something is out there; we just need to see if we can find it," Ballard said at a press conference yesterday. The research isn't all archaeology; scuba divers from one of the research vessels will also observe conch, parrotfish, and manta rays on the shallow reefs.
"It's a worthwhile endeavor," says archaeologist Michael Walters of Texas A&M University in College Station. "The Gulf Coast is a logical place to look for submerged sites." But David Meltzer, an archaeologist at Southern Methodist University in Dallas, Texas, says that the salt deposits wouldn't have been his first target. Rather, Meltzer says that there is certainly a submerged site, about 13,000 years old, from which spearheads wash onto McFaddin Beach, Texas. "You'd probably have much better chance" of finding artifacts there, he says. As for older signs of human presence, Meltzer adds, the place to go is the Pacific Northwest, where the immigrants first arrived.