"This was the stage when humans gradually shifted from hunting large mammals like mastodon and caribou to fishing, gathering and agriculture," said anthropologist John O'Shea. "But because most of the places in this area that prehistoric people lived are now under water, we don't have good evidence of this important shift itself– just clues from before and after the change.
"One of the enduring questions is the way the land went under water. Many people think it must have been a violent event, but finding this large wood object just sitting on the bottom wedged between a few boulders suggests that the inundation happened quickly but rather gently. And this in turn suggests that we'll find more intact evidence of human activity in the area."
With support from the National Science Foundation (NSF) and the National Oceanic and Atmospheric Administration (NOAA), O'Shea and U-M colleague Guy Meadows began exploring the area in the middle of modern Lake Huron several years ago. In 2009 they reported finding a series of stone features that they believe were "drive lanes" used by ancient PaleoIndian hunters to funnel caribou to slaughter, a technique still used today by the Inuit. These drive lanes were located on the Alpena-Amberley Ridge, a land connection across the middle of modern Lake Huron that linked northern Michigan with central Ontario during the low-water periods of the Pleistocene and early Holocene ages.
Since that discovery, O'Shea and Meadow have worked on identifying human campsites, which are typically located away from hunting areas. Piloting their 25-foot boat, the S/V Blue Traveler, about 40-60 miles out into Lake Huron from Alpena, Michigan, the researchers first spotted the ancient wood object using a small hand-deployed remote operated vehicle (ROV) equipped with a video camera. Then a team of divers – including O'Shea – went down about 100 feet to retrieve it.
Initially stored in a PVC tube filled with lake water, the specimen's age has now been fixed using carbon dating. It is currently undergoing more detailed analyses to determine whether there has been human modification, which visual examination suggests. "The first thing you notice is that it appears to have been shaped with a rounded base and a pointed tip," O'Shea said. "There's also a bevel on one side that looks unnatural, like it had to have been created. It looks like it might have been used as a tent pole or a pole to hang meat."
In addition to the wood specimen, the U-M researchers have collected many other samples from the bottom of the lake that they hope will provide clues about the environment before it was submerged by the rising lake water. Some of the samples are now being analyzed at U-M, while others are being analyzed by a Canadian expert on submerged site reconstruction and microdebitage – the examination of flakes of stone that are less than one millimeter in diameter, produced in large quantities when stone tools were made.
So far, according to O'Shea, quantities of pine pollen and charcoal have been found. "Slowly, the environmental picture is filling in," he said. "There was a marsh close by this site. It seems we're narrowing in on people, but of course forest fires could have created the charcoal as well as cooking fires. So we need to wait for the analyses to be sure about what we've got here."
O'Shea and colleagues will also need to wait for calmer weather before they can resume their search for evidence of human life under the great lake.
This research was carried out in collaboration with NOAA's Thunder Bay National Marine Sanctuary and with the Great Lakes Division of the U.S. Navy's Sea Cadets Corp, both based in Alpena, Michigan.
O'Shea is a professor of anthropology at the U-M College of Literature, Science, and the Arts (LSA) and Curator of Great Lakes Archaeology at the U-M Museum of Anthropology. Meadows is a professor of physical oceanography at the U-M College of Engineering.
Diane Swanbrow | EurekAlert!
GPM sees deadly tornadic storms moving through US Southeast
01.12.2016 | NASA/Goddard Space Flight Center
Cyclic change within magma reservoirs significantly affects the explosivity of volcanic eruptions
30.11.2016 | Johannes Gutenberg-Universität Mainz
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy