The Page-Ladson Site in Northwest Florida

During the late Pleistocene sea level contracted because much of earth’s atmosphere was locked in glacial ice.  The land area of what today is Florida doubled in size, and shorelines extended 50-100 miles west into the Gulf of Mexico.  The water table fell and many present day small rivers did not yet exist.  Instead, the land was pockmarked with many spring-fed ponds that attracted herds of megafauna and other wildlife.  The basal chemistry of these waters preserved bones and organic matter, and later when water tables rose, the Aucilla River began flowing and it covered these ponds with sediment.  The Aucilla River flows over 4 known Pleistocene pond sites–Page-Ladson, Latvis-Simpson, Sloth Hole, and Little River Quarry.  These sites contain deep layers of mastodon dung deposits.  Bones and artifacts are often mixed with the ancient piles of turds, and tracks are also visible where mastodons stepped on their own shit.  Scientists studied the dung and identified the plants mastodons ate.  Their favorite foods in Florida were cypress and buttonbush twigs and cones, but they also fed heavily on aquatic plants, oak leaves and acorns, and fruit including persimmon, plum, crabapple, grape, pokeberry, and wild squash.  At Latvis-Simpson a female mastodon skeleton with a fetus was excavated from a dung deposit.  Other dung deposits contain stone and ivory tools made by humans.

Location of the Aucilla River. This river didn’t exist until about ~13,000 years ago.  It cuts through the site of spring-fed ponds that attracted megafauna, and eventually humans for thousands of years.

A mastodon tusk.  Cut marks on a mastodon tusk found at Page-Ladson suggests humans butchered it for a fatty chunk of meat.

 

 

 

 

 

 

 

Radiocarbon dating of dung deposits at the Latvis-Simpson site indicated the oldest layer goes back to 32,000 BP.  The Page-Ladson site is not as old, but deposits there show man overlapped with megafauna as early as 14,550 years ago, predating the Clovis era.  The list of species remains found at the Page-Ladson site (just some of the fauna that overlapped with man) includes 2 species of gar, 2 species of pickerel, 5 species of catfish, 2 species of suckerfish, 7 species of bream, largemouth bass, black crappie, 3 species of frog, amphiuma, siren, Fowler’s toad, snapping turtle, an extinct subspecies of box turtle, gopher tortoise, an extinct species of giant tortoise, rattlesnake, alligator, great blue heron, pied-billed grebe, cormorant, Canada goose, duck, bald eagle, an extinct species of eagle, California condor, an extinct species of stork, red-shouldered hawk, red-tailed hawk, mourning dove, opossum, beautiful armadillo, pampathere, Jefferson’s ground sloth, Harlan’s ground sloth, raccoon, black bear, river otter, margay cat, bobcat, dire wolf, domestic dog, fox squirrel, beaver, muskrat, Florida muskrat, porcupine, capybara, mastodon, mammoth, bison, large-headed llama, stout-legged llama, white-tailed deer, long-nosed peccary, flat-headed peccary, horse, and tapir.  Remains of the extinct Florida spectacled bear have been collected from other Aucilla River sites, and large carnivores such as saber-tooths and jaguars left remains throughout much of the state’s other fossil sites.  Mastodon remains outnumber mammoth remains by a ratio of 4 to 1 at Aucilla River sites.  The former preferred aquatic wooded habitats, while the latter liked grassy open plains.  Remains thought to be of domestic dog may actually be coyote bones because the 2 species are difficult to distinguish from just skeletal remains.

My Georgia Before People blog was in part inspired by information gathered by the scientists who excavated the Aucilla River fossil sites.  So of course, I must highlight a new study of the Page-Ladson site.  Radio-carbon dates of organic material associated with human artifacts have long yielded dates in excess of 14,000 calendar years.  Many archaeologists dismissed these dates…they assumed error in the dating.  This new study was exhaustive–the scientists took 71 radiocarbon dates using the most modern methods–and they determined humans began frequenting the pond 14,550 years ago.  They confirmed that a mastodon tusk found here showed clear evidence of human butchery.  There are 2 additional examples of human butchering megafauna from Aucilla River sites.  Humans likely used these water sources opportunistically to specifically hunt big mammals.

The study also looked at sporormiella volumes.  Sporormiella is a fungus that grows on dung, and it can be used as a proxy for megafauna abundance.  Sporormiella volume spiked 13,700 years ago but then declined, and apparently the local megafauna became extirpated from the region by 12,600 years ago. This is within the accepted terminal extinction dates for Pleistocene megafauna.  Sporormiella volume briefly increased again about 10,000 years ago.  Researchers attribute this to a temporary migration of bison into the region, though this is based on the assumption that other species of megafauna were extinct by then.  I don’t agree with this assumption and believe local populations of now extinct Pleistocene megafauna persisted until the early Holocene but at levels so low they are difficult to detect in the fossil record.

The sporormiella spike at 13,700 is about 800 years after the first appearance of man in the region.  The entrance of man is also associated with an increase in charcoal from man made fires, and I might add, a change in climate to more frequent lightning storms.  I propose anthropogenic fires improved habitat for megafauna leading to an initial increase in megafauna populations.  But man eventually hunted these species to extinction.  As Gary Haynes proposes, the long term drought that occurred during the Younger Dryas cold snap likely concentrated megafauna around dwindling water sources, making them more vulnerable to human overhunting.

References:

Halligan, Jessi; et. al.

“Pre-Clovis Occupation 14,450 Years Ago at the Page-Ladson Site, Florida and the Peopling of America”

Science Advances May 2016

http://advances.sciencemag.org/content/2/5/e1600375

Webb, David (editor)

The First Floridians and the Last Mastodons: the Page-Ladson Site in the Aucilla River

Springer 2006

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The Saltville Fossil Site in Virginia

A dense forest of white pine, spruce, fir, and oak  grew in the Saltville River Valley 17,000 years ago.  There were also some alder swamps and wet sedge meadows, but unlike in the regions to the south and west of this locality, there were no prairies or open woodlands.  The Saltville River Valley is located in southwestern Virginia and during the last Ice Age, this area was much colder than the region located immediately to the south.  The oceanic Gulf Stream that carries tropically-warmed water north as far as the Canadian coast today, instead only went as far north as the Virginia/North Carolina border during the Ice Age.  This meant dry land temperatures in what is now Virginia were as much as 10-15 degrees Fahrenheight  cooler on average than those about 50 miles  further south.  Consequently, the environment in the middle Atlantic States decisively differed from most of southeastern North America.

Location of the Saltville River Valley.

Saltville, Virginia is located in a beautiful valley.  A large lake, known as Lake Totten, covered much of the valley from ~13,500 BP-~8,500 BP.  Salt mining operations have upset the hydrology here, and today as much as 20% of the valley is underwater. 

The Ice Age began waning about 15,500 years ago.  The Laurentide Glacier slowly receded, and the melting ice increased the flow of water into the Saltville River.  Sediment carried by the increased flow formed a mud dam in the Saltville Valley gap, causing the water to backflow and create Lake Totten.  The outflow was captured by another river.  Many of the species of large mammals that lived in North America then were attracted to the abundant salt springs in the area.  The individuals that happened to die during periods of increased sediment flow were buried by mud and preserved for fossil enthusiasts and scientists to find thousands of years later.

An assortment of fossils found at Saltville.  The animals were buried by mud carried by river surges resulting from melting glacial ice to the north.  Paleontologists have to pump out groundwater from their excavation sites here.  Salt mining operations have caused much of the land to flood.

The Saltville fossil site is the most southerly known location where specimens of woolly mammoth (Mammuthus primigenius) have been excavated.  Specimens of Columbian mammoth (Mammuthus columbi) have been excavated here too, showing the 2 species co-existed in some locations.   The 2 species of mammoth have also been found together at a site in South Dakota.  Columbian mammoths ranged much farther south than woolies, having occupied territory as far south as what today is Florida.  Other megafauna species recovered at Saltville include mastodon, Jefferson’s ground sloth, woodland musk-ox, bison, stag-moose (Cervalces scotti), caribou, white tail deer, horse, and giant short-faced bear (Arctodus simus).   Scientists have yet to publish their findings on the smaller species of animals discovered in the fossil deposits.

Puncture mark on a mammoth heal bone made by a giant short-faced bear’s canine.

Gnaw marks on an ankle bone, probably made by a dire wolf.

A mammoth heel bone excavated from this site has a puncture mark that matches the canine of a giant short-faced bear.  This species of bruin is thought to have specialized in kleptoscavenging.  (See: https://markgelbart.wordpress.com/2012/12/10/bearzilla-the-biggest-bear-in-history/) The ankle bone of the same animal was gnawed on by a canid, probably a dire wolf.

A study of the bone chemistry of fossil herbivores from this site had an unexpected result.  All the herbivores living in this region then ate C-3 (carbon 3) vegetation–trees, shrubs, and some herbs.  Even species such as mammoths, bison, and horses that predominately subsisted on C-4 vegetation (grass) elsewhere were restricted to a diet of twigs, leaves, bark, and herbs here.  This is considered evidence that prairies were absent from this particular region during this time period.  The authors of this study admit their findings weren’t sufficient evidence to make any conclusions about megafauna extinctions.  Yet, they suggested competition between grazers and browsers for the same resources may have caused megafaunal extinctions.  I disagree with this conjecture.  Instead, I think their findings are strong evidence against climate change as a cause of megafaunal extinctions because the study shows these animals were not picky eaters and could adapt well to changing environmental conditions.

Humans apparently killed, butchered, cooked, and ate a mastodon at Saltville 17,000 years ago.  Archaeologists found cut marks on a mastodon’s bones as well as congealed grease that could only be the result of cooking.  They also found heat-cracked rocks used in the cooking process.  Pre-Clovis artifacts found associated with the mastodon bones include 2 sandstone knives, a chert blade made out of rock transported from some distance away, and flakes (debitage) from tool-making.  The site was occupied 3 times prior to the Clovis era.  The most recent pre-Clovis horizon dates to about 15,000 years ago and includes a midden containing hundreds of shells from giant floater clams.  This species of freshwater mussel grows to 10 inches long and used to be abundant in North American waters before modern day pollution and river damming.

Giant floater clam (Pyganodon grandis).  I’ve never eaten a freshwater mussel, but they smell like delicious oysters.

Saltville is not a new site.  Thomas Jefferson knew about fossils found here.  Scientists have been excavating fossils off and on here for over 200 years.  A team from East Tennessee State completed the most recent excavation this year.  They visited local amateur fossil collectors to examine their specimens, and they are surveying caves in the nearby mountains in the hopes of finding more fossils to help piece together the regional late Pleistocene ecology.  We haven’t heard the last about this site.

References:

France, Christine; et. al.

“Carbon and Nitrogen Isotopic Analysis of Pleistocene Mammals from the Saltville Quarry (Virginia USA): Implications for Trophic Relationships”

Paleogeography, Paleoclimatology, Paleoecology 249 2007

Schubert, Blaine; and Steven Wallace

“Late Pleistocene Giant Short-Faced Bears, Mammoths, and Large Carcass Scavenging in the Saltville Valley of Virginia, USA”

Boreas 38 (3) August 2009

The Coats-Hines Pre-Clovis Site in Williamson County, Tennessee

Workers constructing the 13th hole of the Crockett Springs Golf Course in 1977 unearthed mastodon bones.  Paleontologists took note of the discovery and 17 years later when they learned lots adjacent to the golf course were going to be transmogrified into residential housing, they surveyed a nearby drainage ditch and found another partial mastodon skeleton along with fossils of horse, deer, a canid, muskrat, turkey, painted turtle, and frog.  This time they also discovered evidence that attracted archaeologists–10 stone tools and 24 lithic flakes.  The tools included a bifacial knife and hide scrapers made from local Fort Payne chert.  Moreover, there were butcher marks on the mastodon backbone, suggesting these ancient Americans removed the proboscidean’s tenderloin.  The apparently butchered mastodon bone yielded radiocarbon dates translated to ~14,000 calender years BP.  Archaeologists regard this as the pre-Clovis era.

Williamson County, Tennessee. 

Photo of the Nashville Golf and Country Club which was formerly known as the Crockett Springs Golf Course.  I couldn’t find a photo of the 13th hole where the mastodon bones were found.  I don’t know which hole this is.

A 3rd survey of the drainage ditch in 2005 found parts of yet another mastodon, and a few years later in this generous spot they found fragmentary evidence of a large Pleistocene mammal, but it was in such poor condition, it couldn’t be identified.  Underneath this, they recovered a Pleistocene-aged deer antler.  In 2010 the owners of the new house built next to the drainage ditch gave permission to the archaeologists to dig a deep trench in their backyard.  Here, the archaeologists found 1582 fragmented bones of mastodon, deer, turkey, turtle, and frog along with 11 more human made artifacts all located 10 feet below the surface of the yard.

Mastodon bones found in trench.

Mastodons roaming future golf course.

The home owners were nice enough to let archaeologists dig this deep trench in their backyard.  I had a trench like this dug in my backyard a few months ago.  Unfortunately, they didn’t find any fossils.  They were replacing the drainage line for my septic tank.  Cost me $5,000.

Geologists think the Coates-Hines site was an intermittent pond that existed between 22,000 BP-12,000 BP.  A stream periodically became blocked, creating the pond, then on occasion it drained.  I propose beavers were the agent that blocked the stream.  Every so often, predators would kill all the beavers in this locality, and the dam would fall into disuse and break down.  A new population of beavers would recolonize the site, and the cycle would begin anew.  About 12,000 years ago, rain washed soil down the adjacent hillside and buried the old pond site and stream with colluvial sediment.

The ancient beaver pond provided an ideal location for a Paleo-Indian base camp.  The ancient Americans opportunistically ambushed big game that browsed aquatic plants, but they also had easy access to muskrats, turtles, fish, frogs, and edible plants such as cattails.  All the species of fossil animals found at this site are notably edible.

Reference:

Wolf, Aaron; Jesse Tune, and John Broster

“Excavations and Dating of Late Pleistocene and Paleoindian Deposits at the Coats-Hines Site, Williamson County, Tennessee”

Tennessee Archaeology 5 (2) Fall 2011

http://csfa.tamu.edu/cfsa-publications/Tune-TA5-2011.pdf

A Probable Pre-Clovis Bison Butcher Site in Washington

Archaelogists believe they’ve found evidence of a bison butchered by humans 14,000 calender years ago.  In 2003 workers digging a pond on Orcas Island, which is adjacent to Vancouver Island in the Pacific Northwest, uncovered a complete skull of an extinct bison (Bison antiquus) along with 97 bones from the same animal–the most complete specimen ever found.  One of the workers kept it in a box in his toolshed until 2005 when he finally turned it over to Stephen Kenady, a local archaeologist. 

Map of Orcas Island.  These islands used to be part of the mainland during the Ice Age when the ocean receded due to an increase in glacial ice.  Many fossils of Pleistocene mammals have been discovered in the region, including other bison fossils, giant ground sloth, and giant short-faced bears.  Low acid bogs are abundant here, explaining the abundance of fossils.  The Paisley Cave pre-Clovis site, where 14,000 year old human coprolites were discovered, is also nearby.

Upon examination of the bones, Dr. Kenady, Randall Shalk, and Robert Mierendorf determined the animal had been butchered by humans.  The taphonomy of the bones–green fractures and cleaver-chopped bone–strongly matched those of other known butchered bones from Clovis and post-Clovis archaeological sites.    Bones from the best edible cuts were missing–another clue.  And the bones weren’t scratched as if they’d been water transported which would be an explanation for how they could resemble being butchered.  The scientists believe the animal either was killed by humans or died naturally on a frozen pond in winter.  During spring the ice melted, and the bison sank to the bottom of the pond to become buried under mud when the body of water silted over and became a low acid bog.

Skull of Bison antiquus.  This species of bison had horns intermediate in size between extant modern bison (Bison bison) and the also extinct long-horned bison (Bison latifrons).  From google images.

Photo I took of a long-horned bison housed at the Georgia College Museum in Milledgeville.  This fossil was found at Clark Quarry near Brunswick and is the only complete skull ever found in the state of this species.

Photo I found of long-horned bison horns from google images.  I added this one because I like the size comparison with the person in the picture.

The modern bison is smaller than both Pleistocene bison species.  Bison antiquus was on average 25% larger, meaning they grew to 7 and 1/2 feet tall and 2400 pounds.  Bison latifrons was even larger.  There are a number of possible reasons why Pleistocene bison grew larger.  The Pleistocene environment may have been a richer foraging environment, and they needed to grow larger to battle large carnivores such as giant panthers, saber-tooths, and dire wolves.  The smaller size of the modern bison may be an adaptation enabling them to run longer distances to avoid human hunters.  The evolution of a smaller size may mean they reach sexual maturity and can breed faster to keep up with the toll of human hunting.  The extinction of large carnivores, and the ascent of human populations likely shaped this evolution to a smaller size.

Both species occurred in Georgia, and they overlapped geographically and temporally.  Bison latifrons may have been a lowland swamp species much like African water buffalo; Bison antiquus may have been an upland species, preferring hilly dry regions.  It saddens me that today there are no wild bison left in the southeast.

Reference:

Lepper, Bradley

“Pre-Clovis Butchers of Bison antiquus”

Mammoth Trumpet 26 (3) July 2011

See also from my June 2010 archives–“Were there three species of bovine roaming the southeast during the Pleistocene?”

The Paisley Cave Pre-Clovis Site

For this week’s blog entry I’m going to step away from southeastern North America and discuss a fascinating site in south central Oregon.  The Paisley Cave site collectively includes 8 different caves and rock shelters created when waves from an ancient Pleistocene Lake (Lake Chewaucan) eroded hollows into the upland bedrock about 17,000 years ago.  By 14,500 years ago weather patterns changed, becoming drier, and the lake receded away from the caves for a distance of about a mile.  But the climate here was still wetter than that of today, and the environment consisted of conifer woodland, meadow, and lakeside marsh; unlike the sagebrush desert which is now the primary type of ecotone at this location.  The caves were ideal shelters for Paleo-Indians, and the surrounding area provided abundant rock (obsidian) for tool-making, and a plentiful supply of big game, small game, waterfowl, fish, and edible wild plant foods.

Most of the caves contain evidence of early Holocene (~9,000o BP)occupation–charcoal from human-lit fires, basketry, and interesting tools such as wooden pegs and sagebrush rope.  But a cave known as Cave number 5 yielded evidence of pre-Clovis material including obsidian projectile points, debitage (the leftover flakes from stone tool processing), and scrapers, all associated with bones of megafauna–a camel ankle bone, the jaw bone of an extinct goat (Harrington’s Mountain goat? Oreamnos harringtoni), bison bones, and two long bones that looked like they were broken for the marrow.  There is one spot in this cave that’s been interpeted as a possible hearth, a  “a bowl-shaped depression with a rock lined base,” where a burned horse bone was discovered.  Moreover, very old processed grass fiber and muscle sinew were found in the cave.  Most importantly, however, was the fossilized human feces carbon dated to 14,290 calender years BP which predates the Clovis era (13,200-12,500 BP).

DNA testing of the feces indicates these people descended from Siberians, meaning they were Asiatic, like native Americans.  An analysis of their fecal content showed they ate bison, dog, squirrel, bird, fish, wild sunflower seeds, and grass.

The Topper site near Allendale, South Carolina (which I visited a couple of years ago) yields tools in soils dating to before Clovis also.

Archaeologists and crew excavating the pre-Clovis trench at the Topper Site in Allendale, South Carolina.  The people there were very nice to me when I visited two years ago.

Tools found in the Aucilla River in Florida also date to slightly before the Clovis era.  I theorize small bands of humans began crossing Beringia and migrating across North America before the LGM (28,000-15,000 BP) when glaciers would’ve blocked their passage.  The reason evidence is lacking is because they were so few in number and so scattered they left little proof.

References:

Pinson, Ariane

“Paisley Caves: What’s the scoop on the poop?”

Mammoth Trumpet 23 (4)  October 2010

www.uoregon.edu/-ftrock/paisley_caves_description.php