the authenticity-bestowing room when credibility proclamations are awarded. Some insiders question whether salvage archaeologists are qualified to criticize academic papers and if non-scientific but mainstream magazines should be writing about archaeological issues. Maybe they are correct.
I had a few reservations about the field; my archaeologist friends instilled in me a healthy skepticism, particularly about the specialized study of First Americans; they acknowledged that setting up two hypotheses as if the truth of one negates the truth of another is a persistent problem of archaeological intellectual life and noted that sample sizes tend to be small and correlation does not explain causation. Nonetheless, tough thinkers surround the profession and I wondered if this dialogue could benefit from an outside interpretive voice.
Underneath, I may have also sensed a bit of resentment (primed by my Montana experience of mainstream archaeology’s dismissal of the Anzick Clovis burial and scientists’ subsequent shifty scramble for the child’s skeletal remains) at the injustice that the larger story, the story of all our people—our American Creation Myth—was patrolled and constrained by an academia whose own literature was frequently composed with a territorial imperative. Yet the field encompassed the landscape of legends, quartered in our childhood dreams of fossil giants and arrowheads. Technical scholarship sometimes swallows the best of this adventure: Could a naturalist’s take on the archaeological material liberate this tale?
I read up on the subject, consuming volumes of material trying to sate my curiosity with the lives of these ice-age pioneers; the depth and range of the controversies surrounding this field of early American archaeology, along with the vehemence and niggling with which these academic wars are waged, astounded me, fascinated me. The richness of the material leapt off the driest scholarly page. Although many strive for the juice of modern discovery, the dozen or so most recent books on the topic, seemed insular (written by archaeologists with other archaeologists in mind) and devoid of the older vitality that lies at the heart of this incredibly journey.
Paradoxically, this is a tough tale to be told by an insider. Given the paltry stack of hard evidence, there’s too much academic territory at stake.
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In 2007, I applied for and received a Guggenheim Fellowship. I spent the next two years reading related scholarly papers; it’s interdisciplinary—archaeology, paleontology, genetics, linguistics, glaciology—but finite and accessible to an informed researcher, such as myself with a dusty degree in geology, graduate study in anthropology, a background in archaeology and the natural sciences. I also talked with a few primary researchers in the field. I can see why this tale is hard to bring to life but, after another year of following stories in the press, and a 2011 Fellowship from the Lannan Foundation, I thought I’d give it a shot.
Why write a book about a journey that took place many thousands of years before any written record, especially during a time when the world seems on fire? After all, these days are the most dangerous times we have seen in the history of the earth. Beyond the agony of modern wars, disease, economics, genocide, torture and starvation, the planet itself and its support systems are in peril. We are experiencing the largest rates of plant and animal extinction on record, rivaling the massive extinctions of the Cretaceous that knocked off the dinosaurs. All around the globe, the air is poisoned and the oceans over-fished. Climate change threatens all species, including humans. Global warming is not a passing phenomenon. It will be there at the end of the day and at the end of our lives. Revisiting an ancient puzzle that unfolded 13,000 to 15,000 years ago might be a waste of time and energy. So, again, why go back and track the odyssey of these bold first Americans?
Human adaptation to climate change is the common underlying theme. However thin the threads of evidence illuminating adaptation to ice-age global warming, I wanted to follow them to some speculative conclusion, even if it merely adds up to a wild guess. Direct comparisons between the two periods of climate change are impossible, rendered unproductive by an unmistakable lack of hard evidence. But the older journey is a great adventure, closer to mythology than science. Life in the Pleistocene is our original emergence story. Our own American Odysseus was out there fighting off ice-age sabertooths and bears with his spear while pursuing mammoth and other giant beasts.
In this spirit, I thought a good adventure story, occasionally with constructive parallelism, might spur us to open our hearts to the undeniable truth that we are again devouring more of the earth’s resources than she has to spare. The book is also a celebration of the North American continent: An exhilarating tale—less prophesy than parable—spun along the lines of exploration in a brand new world beset by the storms of change. The hub of this story reveals adaptation by people coping with extreme climate change, the driving force of our evolution. Tracing the movement of the first people of the Americas’ is ultimately an optimistic trip full of fun and excitement—a message of hope and courage we all could embrace.
| A note on dating and carbon-14Whenever possible, I avoid using radiocarbon dates in this book. Of course, carbon-14 dating is the bread and butter of archaeology, which is ultimately rooted not in the amazing technology of accelerator mass spectrometry but the care and accuracy with which the carbon sample and its provenance are reported. For an outsider to question a particular radiocarbon date might be tantamount to calling the scientist a liar. Archaeology has a colorful history of great big liars (from Piltdown to Sandia) but I leave it to other archaeologists to state reservations about radiocarbon (and other methods) dates from key locations.Briefly, the isotope carbon-14 (C14) is absorbed by plants from the air and moves on into animals until the organism dies. C14 then slowly reverts to N14. Half of it is gone in 5,730 years; another half of that, 25%, decays after 11,460 years and so on. The usefulness of radiocarbon dating fades rapidly for objects older than 45,000 years old. Dates are stated in years before present (BP) with “present” defined as 1950. A range of potential error, plus or minus in years, is provided with each analyzed sample. Calibration of radiocarbon dates to calendar years is neither linear nor especially logical; variation of cosmic particle bombardment from the sun and relative amounts of CO2 stored in the ocean or air all play hell with recalibration. Tree ring chronology provides about twelve thousand years of comparison.I have arbitrarily tacked on a couple thousand years to radiocarbon dates for the period of 15,000 to 12,000 years ago in order to discuss the time of the Great Adventure: Thus the radiocarbon date, 11,000 C-14 yr BP+/- 75 becomes a rough 13,000 years ago, in this case less than a hundred years off the true recalibrated date. For the purposes of telling my story, that’s generally close enough. On occasion, radiocarbon dates are necessary to pin down the precise timing of the opening of the ice-free corridor or the brief panoramic window of Clovis. When you see an exception to rounded-off dates in this book, such as 13,300 or 12,900 years ago, that means the data is translated from the radiocarbon calendar and has been cited several times in peer-reviewed literature. I’d like to attempt to keep it simple. |
| Here is a sample of some rounded off dates that appear several times in the text:30,000 years ago: Marks about the earliest date humans could have appeared in North America. The evidence? Not much: A single site in the Siberian Arctic and inferences from genetic and linguistic studies on extant populations.15,000 to 27,000 years ago: A very cold time of advancing glaciers. By about 20,000 years ago the ice sheets were at their maximum, closing off all routes from Alaska to lower North America. The great megafauna still roamed the ice-free far north but there is no record of humans in the Arctic during this period.13,000 to 15,000 years ago: Very rough dates that denote the time of the so-called pre-Clovis people. It was a time of global warming and rising seas. The archaeological data indicates a couple sites around 14,000 years ago in northeastern Siberia and, about 700 years later, several more along the tributaries of the upper Yukon River in Alaska. South of the ice, a number of credible pre-Clovis dates come from the United States and South America.12,800 to 13,100 years ago: This is the time of Clovis, which probably begins several hundred years earlier than 13,000 years ago, by which date the culture, marked by its iconic projectile point, was full blown and spread across the southern half of the continent. There’s lots of archaeology to pin these dates down. About 12,800 years ago, the warming period is interrupted by a cold snap. The American megafauna, which might have been in decline for a few hundred years, suddenly goes extinct, and Clovis disappears from the archaeological record. |
Chapter 2