Life Traces of the Georgia Coast
Revealing the Unseen Lives of Plants and Animals
Publication Year: 2012
Have you ever wondered what left behind those prints and tracks on the seashore, or what made those marks or dug those holes in the dunes? Life Traces of the Georgia Coast is an up-close look at these traces of life and the animals and plants that made them. It tells about the how the tracemakers lived and how they interacted with their environments. This is a book about ichnology (the study of such traces), a wonderful way to learn about the behavior of organisms, living and long extinct. Life Traces presents an overview of the traces left by modern animals and plants in this biologically rich region; shows how life traces relate to the environments, natural history, and behaviors of their tracemakers; and applies that knowledge toward a better understanding of the fossilized traces that ancient life left in the geologic record. Augmented by numerous illustrations of traces made by both ancient and modern organisms, the book shows how ancient trace fossils directly relate to modern traces and tracemakers, among them, insects, grasses, crabs, shorebirds, alligators, and sea turtles. The result is an aesthetically appealing and scientifically accurate book that will serve as both a source book for scientists and for anyone interested in the natural history of the Georgia coast.
Published by: Indiana University Press
Series: Life of the Past
PREFACE AND ACKNOWLEDGMENTS
What if we all woke up tomorrow and discovered that each fossil shell, bone, impression, or other bodily remains of former life from the geologic past had inexplicably vanished overnight from every museum and every layer of rock? How would we know what life-forms existed before us? How did...
1 Introduction to Ichnology of the Georgia Coast
The large clam fell, however improbably, from a great height above the sandy tidal flat. Three fragments of its thick shell lay in front of me: an entire valve and a small part of the other were still connected by a hinge, and the other chunk was nearby. The main part of its fleshy body was now mostly gone, as were several more...
2 History of the Georgia Coast and Its Ichnology
About 55,000 years ago, as the earth warmed and glaciers melted, the barrier island moved across the landscape in synch with the rising sea. Its oceanward side shifted to the west toward the coastal plain, and its resident biota adjusted and adapted to new locales. Laterally adjacent environments began to succeed one another vertically...
3 Tracemaker Habitats and Substrates
I nearly stepped on the snake, mistaking it for a stick on the trail leading into maritime forest. My oversight was understandable, as the trail was cluttered with branches, leaves, and pine needles, and the snake was relatively small, only about 50 cm (20 in) long. It was also stiff and torpid from the cool shade cast by the long shadows...
4 Marginal-Marine and Terrestrial Plants
It was July 2001, and two full days of fieldwork on Sapelo Island had nearly exhausted our small band of five ichnologists and three eager undergraduate assistants, but in a good way. During those days, we had perused two extensive beaches—Nannygoat and Cabretta, both among my favorite beaches in the world—and looked at these and their dunes for invertebrate and vertebrate traces. So far, we...
5 Terrestrial Invertebrates
I was surprised, yet not surprised, to find out I was wrong. This feeling of humility is a common one among scientists, especially natural scientists who go outside to test what they learned indoors, whether this knowledge was gained through books, journal articles, Web sites, hearsay, or Web sites repeating hearsay. The habit of correction becomes even more acute among ichnologists, particularly...
6 Marginal-Marine Invertebrates
No matter how many times I visit the beaches of Sapelo Island, its sediments always hold surprising traces. On this particular morning in June 2008, my wife, Ruth, found the wonder-inducing trace of the day and directed me to it, just before she left to show some of our companions a fresh sea turtle trackway further south on the beach. This was also well before my ichnologic partner in crime...
7 Terrestrial Vertebrates, Part I: Fish, Amphibians, Reptiles
One July morning, on what promised to be another hot day, our merry group of ichnologists walked along Cabretta Beach on Sapelo Island at low tide and stared at the sand, a typical activity for those with our interests. After all, we were keenly interested in the burrows and tracks left by animals in the extensive sand flats of this beach; moreover, we could do it privately, as our footprints were the...
8 Terrestrial Vertebrates, Part II: Birds and Mammals
I could not help but notice the dead body of the opossum (Didelphis virginiana), a dark lump on an otherwise light brown sandy road, as I traveled through Hog Hammock (Sapelo Island) that last morning of July. Squinting through the dusty windshield of a UGA Marine Institute pickup truck, I slowed the vehicle and...
9 Marginal-Marine and Marine Vertebrates
Sea turtle trackways are perhaps the most impressive of marginal-marine vertebrate traces anyone can stumble upon on a Georgia beach, and this one was no exception. But because my wife, Ruth, and I were infrequent visitors to the coast, we had never seen one in all of its glorious three dimensions. Its presence that June morning...
10 Trace Fossils and the Georgia Coast
Yellow Banks Bluff on St. Catherines Island is one of those places where the people who named it limited themselves to pure description and allowed for no flights of fancy. It is indeed a yellowish, banked bluff, forming an outcrop about 4 m (13.1 ft) tall and 600 m (1,970 ft) long, extending much of the length of a beach on the...
11 Future Studies, Future Traces
A self-deprecating realization struck me in the middle of the fall of 2008, as startling as looking in a mirror and suddenly noticing a large, unsightly growth projecting from the side of my head. I had been spending too much time inside lately, devoted largely to teaching classes; grading exams (or, more likely, putting off their grading...