At Least 1 Species of Giant Ground Sloth (Eremotherium laurillardi) Lived in Groups

Some scientists have long suspected at least 1 species of giant ground sloth lived in groups.  The bones of Eremotherium laurillardi are often found in intergenerational assemblages, and there is a large degree of sexual dimorphism within the species.  Animals with large males and small females or vice-versa tend to live in social groups.  Lions are an example of this.  However, most of the sites where mixed-age assemblages of E. laurillardi occur were difficult to interpret–scientists were unable to determine whether the collection of bones came from a simultaneous die-off or accumulated over a long period of time.  But a site in southwestern Ecuador known as Tanque Loma does contain bones of E. laurillardi that clearly resulted from a simultaneous die-off.

Photo of the Tanque Loma excavation from the below reference.

Scientists excavated 575 specimens of E. laurillardi from at least 22 individuals at the Tanque Loma site.  They found less than 100 bones of other species including  gompothere (a type of mastodon), glossotherium (a smaller species of ground sloth), pampathere (a very large armadillo), horse, and deer in the same genus as white tail deer.  The bones of E. laurillardi come from individuals of different ages and sexes, suggesting it was a social group. Sloth coprolites and stomach contents were found as well, but the plant remains have not been identified or if they have the results have not been published yet.  Tanque Loma was a temporary marshy pond that apparently dried up during dry seasons, then periodically refilled during rainy season.  This region of Ecuador was a tropical grassland during the Last Glacial Maximum, similar to modern day East Africa.  The remains are estimated to be between 18,000-23,000 years old, but the conditions of this site make radiocarbon dating less reliable.  Humidity and the presence of tar interfere with accurate radio-carbon dating.  It was not a tar pit trap because the tar seeped into the deposit after the animals had been dead for a long time.  The bones were preserved when they were quickly buried in a low oxygen environment.

Replica skeleton of Eremotherium laurillardi mounted at a museum on Skidaway Island.  They were common along the Georgia coast during interglacials.  They reached 20 feet in length and weighed over 4 tons.  They may have been hairless like elephants and unlike other ground sloths.

The authors of this study believe this group of sloths died when the marsh shrank and the sloths fouled the water with a concentration of their own fecal matter.  The high nitrogen input may have caused a toxic algal bloom that poisoned the group, the members of which died within a few weeks.  Large mammal die-offs like this occur in East Africa today, especially among hippos when they are congregated around shrinking water holes.

E. laurillardi ranged into Florida and coastal Georgia during warm interglacials, but they disappeared from the region at least 30,000 years ago.  They were not as well adapted to temperate climates as Harlan’s ground sloth and Jefferson’s ground sloth (which occurred in Alaska).  These latter 2 species had furry coats and dug deep burrows.  Eremotherium may have been hairless and may not have dug deep burrows.  The temperate species of ground sloths didn’t become extinct in North America until men wiped them out.

Reference:

Lindsay, Emily; et. al.

“A Monodominant Late-Pleistocene Megafauna Locality from Santo-Elena, Ecuador: Insight on the Biology and Behavior of Giant Ground Sloths”

Paleogeography, Paleoclimatology, Paleoecology 544 April 2020

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The Red River Raft

I came across this remarkable phenomenon while re-reading America as Seen by Its First Explorers by John Bakeless. About 900 years ago, a flood washed a bend of land and all the trees on it into the Red River.  (The red clay substrate makes the water red, hence the name.) The trees and sediment caused a logjam and subsequent floods kept washing more and more debris into it so that by 1830 the logjam, known as the Red River Raft, was an incredible 165 miles long.  The sediment was so deep trees, bushes, bamboo, and grass sprouted on the logjam.  Forests of cypress, cedar, cottonwood, willow, sycamore, oak, and persimmon grew over the river, and many pioneers didn’t even realize they were passing over a river when they crossed it. Some of the trees were 10 inches in diameter. The logjam forced the river to shift positions, often leaving behind fertile soil where the Caddo Indians planted crops.  The impenetrable thickets and unnavigable river protected the Caddo Indians from European settlers and kept them isolated from other hostile tribes.  The logjam created 5 major lakes as well, and these attracted huge flocks of waterfowl.  Natural channels wove their way through the logjam, but it was impossible to travel through it by boat.

Map of the Red River and some of its tributaries.

Photo of part of the Red River Raft after it reformed during the 1870s.

Henry Shreve (the city of Shreveport was named after him) began dismantling the Red River Raft during the 1830s.  He used a giant winch on a steam boat to remove logs from the bottom up and he dug channels through the raft itself.  He successfully cleared the Red River Raft but warned that it could reform, and a few decades later it did.  Eugene Woodruff dismantled the reformed raft during 1873, but this increased water flow through the Mississippi River and flooded parts of Louisiana.  The Army Corps of Engineers was forced to build the Old River Control Structure to prevent disastrous flooding downstream.

Boat with winches used to clear trees from the Red River Raft.

Log jams over 100 miles long must have occurred sporadically during the Pleistocene, providing unique habitat for land and aquatic flora and fauna.

The 57 Year Old Fire in Centralia, Pennsylvania

A month after I was born, the town fathers (or maybe they should be known as the village idiots) of Centralia, Pennsylvania thought it would be a good idea to burn the county landfill.  This garbage dump was located next to a coal strip mine in operation since 1935.  The fire ignited an underground coal seam, and it is still burning 57 years later.  3 major attempts to extinguish the fire failed.  Authorities estimate the fire will keep burning for another 250 years, and it will continue to release mercury, sulfur dioxide, nitrogen oxides, particulates, heavy metals, carbon monoxide, and carbon dioxide–all the poisons found in coal.  Heat from the underground fire buckles streets and kills trees.

Location of Centralia, Pennsylvania.

Aerial view of Centralia–abandoned homes and dead brown trees.

This road is destroyed and smoke sometimes comes through the cracks.  These photos and more can be found within this Business Insider article.  https://www.businessinsider.com/photos-of-abandoned-centralia-pa-2012-5#centralia-is-a-borough-in-the-northeastern-mountains-of-pennsylvania-in-2002-the-us-postal-service-revoked-the-towns-zip-code-17927-1

The town of 1,492 people became quite uninhabitable. During 1984 Congress allocated $42 million to relocate the residents, and the population today is 5.  I tried to determine if wildlife has moved into the area since the people left (like what happened at Chernobyl and the Korean demilitarized zone), but I can’t find anything about it.  For sure this ghost town is an example of the folly of man and in stark contrast to the blog article I wrote last week describing the travels of a man who visited Pennsylvania when it was still mostly a beautiful wilderness.

 

Thomas Ashe’s Journey through Pennsylvania and Down the Ohio and Mississippi Rivers during 1806

An Englishman by the name of Thomas Ashe visited the United States during 1806 and wrote about his experience in a book that was published during 1808 and is available for free online (See: https://books.google.com/books?id=Qz8VAAAAYAAJ&pg=PA44&lpg=PA44&dq=Thomas+Ashe+journey+through+pennsylvania&source=bl&ots=c2zVsqVifo&sig=ACfU3U2hyAJ1LaSWy_ztMUG0zi5t-bKWVw&hl=en&ppis=_c&sa=X&ved=2ahUKEwjHopfxsY3nAhVNeKwKHXSeDR4Q6AEwCXoECAcQAQ#v=onepage&q=Thomas%20Ashe%20journey%20through%20pennsylvania&f=false ).  His account of the natural history, people, and early American towns fascinates me.

He began his journey in eastern Pennsylvania and traveled over some mountains.  One night, darkness overcame him before he could reach the next settlement, and he was forced to stop on the trail because he was afraid he or his horse might walk off a cliff.  Animals kept him awake all night.  First, a bobcat noisily toyed and killed an opossum next to his camp.  Then whip-or-wills, owls, and wolves serenaded him.

Ashe was already too late to see live bison, though all of the overland trails followed former bison migration routes.  He talked to 1 old-timer who told him that he made the mistake of building his log cabin on a bison trail.  When the bison came through, they rubbed themselves on his cabin and eventually pushed all the logs apart and destroyed it.  The next year he killed more than 600 and when the rest of the herd saw the carnage they never returned to the area.  Deer and elk were still abundant in some areas Ashe visited but not all.  Bear were so common that a bear skin rug sold for $1.  Ashe shot and killed a bear for no reason, though he instantly regretted it.  Wild hogs roamed the forest for acorns and roots.  Settlers didn’t want them near their cabins because they attracted predators.

Ashe bought a 40 foot long Kentucky boat complete with roof, chimney, and chicken coop; and he brought along 2 servants and a dog.  He boated down the Ohio and Mississippi Rivers and explored some tributaries.  Occasionally, he anchored his boat and took some overland forays.  In Louisiana he bought some ducks and put them in his chicken coop, but a large alligator stopped the boat, seized the chicken coop in its jaws, carried it to shore, smashed it, and ate the ducks.  Ashe claims the alligator was 20 feet long, but I’m sure that was an overestimate.  He killed another “20 foot long” alligator with 3 shots and kept 2 juveniles as pets to take back to England.

A Kentucky boat.  They had flat bottoms.  Snags and rapids made boat travel difficult during the 19th century.

Ashe saw 30 species of snakes and over 180 species of birds.  The richest forest he saw was near Dayton, Ohio–it consisted of sugar maple, sycamore, mulberry, oaks, walnut, butternut, aspen, basswood, ironwood, ash, sweetgum, chestnut, hickory, cherry, horse chestnut, honey locust, magnolia, elm, crabapple, sassafras, pawpaw, plum, crabapple, dogwood, grape, and wild cotton.  Past Dayton were a chain of beautiful prairies with geraniums and passion flowers.  The topsoil in some areas he visited was an astonishing 30 feet deep.  The soil was too rich for wheat, causing it to grow tall and make little seed.  Settlers told him they had to grow corn 7 years in a row on a plot before it was exhausted enough to produce a wheat harvest.  Ashe also came across salt springs which attracted game, and places where petroleum flowed near the surface.  People then didn’t know the future value of this resource and thought it might be medicinal.

At this early date developers had yet to level or bury Indian mounds and abandoned villages.  Ashe was critical of the locals for pilfering through old Indian gravesites and mounds, yet he did it too.  At 1 site he went through hundreds of graves searching for gold.  All he found was fools gold.  He explored a cave in Indiana that sported hieroglyphics.  These possibly represented Pleistocene mammals–elephant (mammoth or mastodon?), wild boar (peccary?), and sloth. I’ve never found a report of this in the scientific literature.  Ashe got lost in the cave and fired his gun, so his companions could locate him.  This aroused all the owls and bats in the cave.  The cave was the former haunt of a gang that robbed and killed hundreds of river travelers.  It was also the site of a battle between Indians and settlers, resulting in hundreds of deaths as well, and there were piles of human and animal skeletons all about.  Ashe did find fossil bones at several sites, including a mammoth tusk.  1 site was known as “bone valley.”

It’s interesting to read Ashe describe modern day large cities the way they were during their infancy.  Pittsburgh was a town of 400 houses, 2000 people, and 40 stores where beef sold for 3 cents a pound.  Most residents were Irish.  Wheeling, Virginia (now West Virginia) had 250 homes along with saw mills and flour mills.  St. Louis was a town of Cajuns where the women worked, the children played, and the men performed music all day.  Every house had a band with a guitar player, fiddler, and lead singer.

Earliest known painting of Pittsburgh, circa 1804.  

When Ashe traveled through the wilderness between towns there was usually an inn within a day’s journey.  An inn meant a log cabin where cornbread, bacon, and whiskey were served–not necessarily in that order.  Lodging was 25 cents a night and meals were the same.  Back then, a dollar was a coin and to make change the dollar was literally cut into quarters, dimes, and nickels.  The culture in some of the frontier towns was rough.  In Wheeling the entire town closed up shop for the rest of the day when there was an horse race or cock fight.  Fighting between men was popular too.  Ashe witnessed 2 men fighting in a “rough and tumble” bout.  They were given a choice of fighting with rules but they chose “rough and tumble” which meant anything goes.  While a crowd of people bet on the outcome, the 2 men fought a brutal battle, and the smaller more skillful man “won” by permanently blinding the larger man.  He suffered an ear completely torn off.  At a bar in town later that night 2 naked black men played banjos while people drank, gambled, and danced.  The noise was so loud Ashe couldn’t hear the banjos.  Towns settled by Irish were mostly like this.  Towns settled by transplanted New Englanders were more orderly and the town fathers outlawed gambling, fighting, and horse racing.

The first cabin Ashe stopped at on his journey served passenger pigeon, cornbread, and coffee made from burned wild peas.  He ate wild game often when traveling through the wilderness.  For example he shot 12 ducks, 1 turkey, and a deer in 1 afternoon.  Boating down the river gave him constant access to a variety of fish including catfish, bass, bream, sturgeon, shad, pickerel, and paddlefish.  He visited a French settlement at Gallipolis where 1 man produced 400 gallons of peach brandy per year for barter.  He shared a feast with them, and his biscuits were the first wheat flour they’d had in months.  They gave him cornbread, cheese, milk, and fruit.  The kids at Gallipolis kept an array of pets–piebald and albino deer, Carolina parakeets, blue jays, wood ducks, woodchucks, opossums, and even a bear.  Some of these doubled as a food source.  One meal Ashe enjoyed was turtle steaks.  During this meal he was serenaded by a flock of Carolina parakeets–what a forlorn nature scene.  Ashe met a man on the road in Kentucky and followed him to his home.  His wife served hot toddies, bacon, squirrel soup, and hominy.  Though the man had been away from home for months, Ashe noted he showed absolutely no affection for his wife or children and didn’t even talk to them.  Divorce wasn’t much of an option then.

In Louisiana at a fort on Chickasaw bluff Ashe was honored with a supper of fish, squirrel, venison, bear, fruit, and pecans.  They served wine made from local grapes, and many of the men ended up literally sleeping  under the table, but Ashe made it back to his boat about 2 am, nearly breaking his neck climbing down the bluff.  Nevertheless, this was a welcome diversion of civilization because most of this region until he arrived at New Orleans consisted of uninhabited forests, canebrakes, and bayous.

Reference:

Ashe, Thomas

Travels in America Performed in 1806

William Savage Company 1808