"The answers to extinction, survival and evolution are right here in the dirt," says University of Cincinnati Quaternary science researcher Ken Tankersley, associate professor of anthropology and geology. "And we are continually surprised by what we find."
While many scientists focus on species' extinction wherever there has been rapid and profound climate change, Tankersley looks closely at why certain species survived.
For many years he has invited students and faculty from archeology and geology, and representatives from the Cincinnati Museum Center and Kentucky State Parks to participate in an in-the-field investigation at a rich paleontological and archeological site not too far from UC's campus.
Through scores of scientific data extracted from fossilized vegetation and the bones and teeth of animals and humans, Tankersley has been able to trace periods of dramatic climate change, what animals roamed the Earth during those epochs and how they survived. And his most recent evidence reveals when humans came on the scene and how they helped change the environment in Big Bone Lick, Kentucky.
"What we found is that deforestation efforts over 5,000 years ago by humans significantly modified the environment to the degree that the erosion began filling in the Ohio River Valley, killing off much of the essential plant life," says Tankersley. "At that point animals had to either move, evolve or they simply died off."
[...]
To effectively date the plant and animal specimens, Tankersley's students examined radiocarbon and optically stimulated luminescence (OSL) ages. Dating much of the material to 5,000 years ago using OSL procedures, Tankersley was shocked to find the evidence for human activity and a new anthropological time period now called the Anthropocene - when humans became the most powerful, natural force.
"So much of science is serendipitous," claims Tankersley. "What the students discovered serendipitously, by dating these deposits, was that humans came in and broke the sod.
Deeper into the sediment, Tankersley found that humans had dug pits into the ground to process animal skins to wear as clothing. Based on ethnographic French literature, the Native Americans had put piles of rocks inside the pits along with hickory nuts, then they used hot rocks to boil the water. The oily, greasy meat of the hickory nut would float to the top and the non-edible remains like the shell and hull would sink to the bottom.
"They would skim it off and drink the water, as it was very nutritious," says Tankersley. "When they were finished, they would grab the softened deerskin and leave the rocks and nutshells behind, which is what we found."
To protect their hickory-nut trees from squirrels and other animals, Tankersley found evidence for human deforestation, where large areas of trees were cleared to create separate hickory-tree orchards, protecting them from animal invasion. That deforestation and degradation resulted in substantial erosion of the uplands, which caused the overbank and backwater flooding of the Ohio Valley area.
The changing vegetation, as a result of this deforestation also contributed to the demise, adaptation or evolution of several species.
Furthermore, Tankersley and his students uncovered evidence for animals being hunted by humans during this same period. Looking closely at the hash marks in animal bones, there was strong clues that humans had greatly contributed to the extinction of some of the species in BBL like the larger bison.
Consequently, through deforestation and arboriculture behavior, and the hunting and extinction of many species of animals, Tankersley found clear evidence that humans indeed contributed to the changing landscape even as far back as 5,000 years ago.
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This is NOT the only case where PreColumbian inhabitants of the Americas made radical changes to their environment. Neglecting the Overkill Hypothesis for the 6th Mass Extinction, the Mississippian Mound Builder Culture including Cahokia, extensively cleared the Mississippi River valley of forest and it only came back when the die-off of Native Americans took place due to European diseases. Likewise, the Mayans brought their own demise in the Classic Period by largely clearing the Yucatan of forest! Then there's the extensive farmlands and cleared areas of the Amazon River Basin for the civilizations which were there prior to the same die off as what killed off the NorAm Mound Builers. The Amazon is far, far from pristine. The Americas were actually in the same devastated state as the rest of the world, a disaster ecology created by the arrival of humanity.
There has been NO CASE of humanity living in harmony with nature.
Its a myth, folks.
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