Archive for the ‘Pleistocene Mammals’ Category

1 Thing I Knew and 2 I Didn’t

March 19, 2020

I’ve learned a couple things this past week in my search for blog fodder.  A new study presented evidence saber-toothed cats fought each other.  This is not at all surprising–I always just assumed this was true.  All extant large mammals battle each other in intraspecific conflict over mates or territory.  Of course, saber-toothed tigers were no different.  However, scientists found actual evidence–2 Smilodon populator skulls found in Argentina (1 by an amateur and 1 by a professional paleontologist) have punctures in them that exactly match the canine of another saber-tooth cat.  Smilodon populator was a huge species of saber-tooth, reaching 750 pounds in weight, that lived in eastern South America until about 11,000 years ago.  It was closely related to the more widespread Smilodon fatalis which ranged throughout most of North America and western South America until the end of the Pleistocene.  Previous studies have suggested Smilodon biting pressure was weak compared to most other species of cats, but apparently it wasn’t that weak…they were capable of puncturing bone.  The same kinds of injuries occur in extant species of cats.  Undoubtedly, most of these wounds are fatal, and the canine of a Smilodon was so long it definitely caused a fatal bite because it penetrated well into the brain.

saber-toothed cat skulls

Saber-toothed cats sometimes died during intraspecific fights.

I was watching a nature show on National Geographic wild entitled Wild Portugal and learned there were wolves still living in Portugal.  This, I did not know.  There is a population of 2000 wolves living in northeastern Spain and northern Portugal, and they are protected, though farmers try to kill them when they can get away with it.  The wolves take an heavy toll on the local sheep.  Some consider them beneficial because they control populations of wild boar.  They also hunt feral horses and deer.  Genetic evidence suggests the Iberian wolf has been isolated from other European wolves since before the Last Glacial Maximum when the populations were separated by a glacier.

Iberian wolf.

I also didn’t know there was a feral population of cats in Madagascar that already evolved to twice the size of a regular house cat.  Arab traders brought cats to Madagascar about 1000 years ago, and they went wild.  The evolution in size is an adaptation for hunting lemurs–a regular part of their diet along with rodents, snakes, and birds.  They outcompete a native predator, the fossa–a distant relative of the mongoose.

Image result for feral cats in madagascar

Feral cat in Madagascar.  They are twice the size of a regular house cat.

Reference:

Chimento, N; et. al.

“Evidence of Intraspecific Agonistic Interaction in Smilodon populator (Carnivora, Felidae)”

Comptes Rendus Palenal 18 (4) June 2019

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

February 28, 2020

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.

Image result for tanque loma

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.

Image result for hairless eremotherium laurillardi

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

Nutria (Myocastor coypus) have Invaded Richmond County, Georgia

January 10, 2020

I think I’m the first person to document the presence of nutria in Richmond County, Georgia.  I was driving down Mike Padgett Highway last week and spotted a large road-killed rodent in the suicide lane, and I assumed it was a small beaver.  On the return trip I got a look at the posterior and noticed it did not have the broad naked tail of a beaver, but it was much too large to be a muskrat.  This specimen was at least 24 inches long, not counting the 12 inch tail, while muskrats grow to just 7-12 inches long.  I pondered over what it could be, and it dawned on me that it was a nutria.  I reviewed the description and photos of nutria in Mammals of Georgia by Stan Tekiela and confirmed my identification. His book was published in 2011 and shows the known range of nutria in Georgia then was along the Atlantic coast and the most southern boundary of the state, but apparently they have expanded their range since.

Image result for nutria nursing while swimming

I have no doubt that I saw a road-killed nutria in Richmond County, Georgia.

I considered taking a photo of the specimen as proof, but it seemed ridiculous to go back and risk getting run over by a car in order to photograph a dead rodent.  Though the traffic is not normally bad at this location, the carcass was in the middle of the suicide lane around a curve in the road.  The specimen was located about half a mile from the nearest water source (Spirit Creek, a tributary of the Savannah River).  Perhaps it was traveling across land to a different stream in search of an unrelated mate.

This species has been expanding its range north through the Savannah and probably other River drainages in Georgia.  They are well adapted for aquatic life and breed fast.  A nutria can produce 4 litters a year of up to 11 kits.  A nutria’s tits are angled to its side, so the kits can nurse with their noses above water while the mother swims.  Their population can explode.

Nutrias are native to South America.  Fur farmers have introduced nutria around the world–the U.K., France, Italy, Russia, and most notably Louisiana.  Fur farmers invariably go bankrupt, and the nutria escape to the wild.  Nutria feed upon the bulbous stem of aquatic plants, often killing them.  This causes erosion when the plant dies and the roots rot away.  To prevent damaged wetlands, some people advocate eating nutria meat, and 1 company even makes dog food from the meat.  Reportedly, it tastes like a cross between turkey and pork.  Cold winters may also contribute to a range reduction, but in Richmond County, we haven’t experienced a severe winter since 2012/2013.

Nutria fossils have been found at 6 sites in South America, dating from the early-late Pleistocene.  Their closest living relative is the painted tree rat ( Callistomys pictus ), an endangered species found in the disappearing Atlantic rain forests of Brazil.

Image result for painted tree rats

Endangered painted tree rat, the nutria’s closest living relative.  They must have diverged from a common ancestor many millions of years ago–1 is arboreal and the other is aquatic.

As far as I know, I am also the only person to document the presence of star-nosed mole in Richmond County.  See: https://markgelbart.wordpress.com/2016/12/02/the-strange-little-star-nosed-mole-condylura-cristata/

Leopardus amnicola and More Additional Specimens of Cenozoic Fauna from South Carolina

November 9, 2019

The Florida Museum of Natural History just published an exciting new bulletin.  The paper describes every Cenozoic fossil specimen found in South Carolina and examined by scientists for the last 17 years–since the late Al Sanders published  Additions to the Pleistocene Mammal Faunas of South Carolina, North Carolina, and Georgia. A link to this new bulletin is at the bottom of this blog entry.

Several new specimens of Pleistocene age are notable.  Fossil hunters found the partial tooth of an extinct species of margay cat ( Leopardus amnicola) from the Ashley River phosphate beds–a first for the state of South Carolina.  A close relative of this species ( L. weidii  ) still occurs in tropical Central and South America.   L. amnicola remains have been found at 12 sites in Florida, 3 in Mississippi, 2 in Georgia, and 1 in Alabama.  Apparently, it was a widespread species occupying forests of southeastern North America.  It likely became extinct during the Last Glacial Maximum when environmental conditions changed to more open landscapes.

A margay cat.  An extinct relative of this species formerly occurred across southeastern North America. 

The most remarkable find was the limb bone (a tibia) of a pseudo-cheetah found on Edisto Beach. Scientists tentatively assiged it to  Miracinonyx ? trumani–a species previously unknown east of the Mississippi.  However, assignment was based on the age (late Pleistocene).   M. inexpectus, a species of pseudo-cheetah common from the Pliocene-mid Pleistocene, is rarely, if uncertainly known from the late Pleistocene.  I’m not convinced the limb belonged to a pseud-cheetah.  Pleistocene cougars ( Puma concolor) grew larger than modern day cougars, and I don’t believe scientists can discern with certainty the difference between pseudo-cheetahs and cougars without examining a skull or teeth.  Pseudo-cheetahs grew larger than cougars, but large Pleistocene cougars overlapped in size with small pseudo-cheetahs.  I covered this topic on a previous blog entry.  (See: https://markgelbart.wordpress.com/2018/05/28/an-anatomical-comparison-between-the-extinct-north-american-cheetahs-miracynonyx-sp-and-the-late-pleistocene-holocene-cougar-puma-concolor/ ) Edisto Beach abounds with subfossil remains of big cats including saber-tooths, giant lions, jaguars, cougars, bobcats, and now possibly pseudo-cheetahs.

More bones of helmeted musk-ox, caribou, and walrus have been found in South Carolina over the past 17 years.  Most people think of these species as beasts of the far north, so it’s curious to realized how far south they occurred before man disrupted the ecosystem.

caribou, Bob Stevens, US Fish and Wildlife Service

Caribou ranged into the middle-south during cooler climate phases.

This is the first paper I’ve read that identified giant beavers from the mid-south as  Casteroides dilophidus.   Recently, paleontologists recognized that extinct giant beavers of the mid-west ( C. ohioensis) were not the same species as giant beavers from the southeast.

Giant Beaver Size Comparison

There were 2 species of giant beavers. C. ohioensis and C. dilophidus.

Several other first specimens found in South Carolina are interesting enough to note here.  The remains of the giant armadillo (Holmesina floridanus) were discovered in Clapp Creek, Williamsburg County.  It dates to the early Pleistocene.  Imagine a 300 pound armadillo.  There is also the first record of a Pleistocene coyote (Canis latrans) from in state.  Pre-Pleistocene first South Carolina finds include fossils of the bone-eating dog ( Borophagus hilli), dating to the Miocene, and hell pig (an entelodont), dating to the Oligocene.

The below linked paper really has some nice tables of South Carolina Pleistocene-aged fossil sites and all the species found at each. Although specimens of 13-lined ground squirrels were already known, I was surprised to learn just how common and widespread they were.  This species prefers open habitats and is absent from the region today.  Its presence suggests more prairie habitats during Ice Ages.

Reference:

Albright III, L. et. al.

“Cenozoic Vertebrate Biostratigraphy of South Carolina, USA and Additions to the Fauna”

Bulletin of the Florida Museum of Natural History  57 (2) October 2019

https://www.floridamuseum.ufl.edu/wp-content/uploads/sites/35/2019/10/Vol57No2archival.pdf

 

 

 

 

 

 

 

The Missing Lynx: The Past and Future of Britain’s Lost Mammals by Ross Barnett

October 19, 2019

Ross's book The Missing Lynx.

Ross Barnett’s new book.

Ross Barnett is a British paleontologist who specializes in analyzing DNA from subfossil specimens of extinct species of cats.  I have referenced his work in at least 4 of my blog articles.  He just published a book about some of the megafauna that roamed Great Britain during the Pleistocene.  His book includes chapters about hyenas, saber-tooths, lions, woolly mammoths, woolly rhinos, Irish elk, bison, aurochs, bears, wolves, Eurasian beavers, and lynx.  I’m familiar with this subject matter but was looking forward to learning something new, and I did.  I learned the most from his chapter on the bovids–the aurochs and bison.  I didn’t know the aurochs (the ancestor of modern cattle) was twice the size of a modern cow. Cave paintings show males were black and females were red–this is something I may have known but had forgotten.  Genetically, the European bison, also known as the wisent, is surprisingly different from the American bison, though they are closely related.  Scientists puzzled over this for a long time.  Cave paintings also suggest differences in the wisent’s appearance over time.  Some are long-horned and robust, while others are shorter-horned and skinnier.  Scientists discovered the modern wisent is actually an hybrid between the bison and the aurochs.  Before 50,000 years ago and after 34,000 years ago European bison appeared more bison-like, but between those dates they were more aurochs-like.  This is recorded in cave paintings as well as genetics.  I think this is the most interesting fact I found in this book.

Ross Barnett explains an ingenious technique scientists use with the tiny bits of DNA they extract from very old subfossils. They add an enzyme from a species of bacteria to the tiny bit of DNA they can extract from a subfossil, and this causes a polymerase chain reaction (polymerase is an enzyme that replicates DNA in cells). This increases the amount of DNA they can analyze.  He was able to analyze the DNA from a 30,000 year old subfossil bone of a saber-tooth cat known as Homotherium latidens.  He determined the 2 lineages of saber-tooths (Homotherium and Smilodon) diverged from the rest of the cats about 20 million years ago.  However, Homotherium and Smilodon were not that closely related to each other.  They diverged 18 million years ago.  But Homotheriums from Great Britain were genetically similar to Homotheriums from the Yukon, and he proposes there was just 1 species in this genus during the late Pleistocene.  Saber-tooths sit on the evolutionary tree between cats and hyenas but are closer to the former.

Ross Barnett strongly leans toward the school of thought that thinks man is responsible for the extinction of most of the megafauna.  This is the only explanation that makes sense to me.  He does favor introducing some species of animals back to Great Britain.  The lynx has been extinct on the island since the 7th century AD.  (Something else I learned in this book–there are 2 species of European lynx: the northern and the Iberian.  At times during pre-history their ranges have overlapped but they haven’t interbred.)  He thinks lynx could be re-introduced with few problems.  They don’t attack people, and farmers could be reimbursed for livestock they might lose.  Lynx would help control the overpopulation of deer in Great Britain.  Apparently, there aren’t enough deer hunters in England.

I discovered just 2 errors in this book.  Dr. Barnett writes bison didn’t colonize North America until 130,000 years BP.  Bison bones excavated from the 10 mile bone bed in South Carolina come from sediment estimated to be from 200,000-240,000 years old.  The presence of bison in North America marks the beginning of the Rancholabrean land mammal age which is thought to have begun about 300,000 years ago.  Bison were in North America prior to his stated date.  He is also unaware that a new species of giant beaver has been named.  Dr. Barnett states Casteroides ohioensis lived in North America from Canada to Florida.  However, the species that lived in Florida and perhaps the mid-south was Casteroides dilophidus.

For people interested in Pleistocene mammals this book is a must read.  Every chapter has nice maps, showing the locations of fossil sites where specimens of each species were found.  The research is up to date but the information is passed on to the reader in a style that is very easy for a layman to understand.

 

Genetic Study Suggests Fox Squirrels (Sciurus niger) and Gray Squirrels (S. carolinensis) May Interbreed

September 14, 2019

Naturalists have observed male fox squirrels chasing female gray squirrels.  Male Squirrels chase female squirrels during mating season, and if they catch the opposite sex, it demonstrates their fitness for procreation.  Fox squirrels have never been observed actually mating with gray squirrels, and as far as I can determine, nobody has ever reported an hybrid between the 2 species.  However, a new study suggests they may interbreed or have interbred in the past.

Fox squirrel a coat of many colors

Black fox squirrel.

021

Melanistic fox squirrel I photographed outside Spring Island, South Carolina.  This was before I had the benefit of a telephoto lens.  Click to enlarge.

It is estimated there could be as many as 25,000 black squirrels in the east of England

Melanistic gray squirrel.

The mutation for having a black coat (melanism) arose twice in fox squirrels from 2 different populations–an example of convergent evolution.  Western fox squirrels have 1 allele associated with melanism, while eastern fox squirrels have a different allele associated with melanism.  (An allele is defined as 1 of 2 or more alternative forms of a gene that arose by mutation and are found on the same place in the chromosome.)  Scientists believe the alleles for melanism in fox squirrels arose for different reasons.  The black coat on western fox squirrels helped them stay warm and more active in a region with colder climate.  The black coat on southern fox squirrels helps camouflage them because it makes them harder for hawks to see in a shady canopy.  The allele for melanism in western fox squirrels is exactly the same as found in melanistic gray squirrels.  Statistical models suggest the most likely explanation is interbreeding between fox and gray squirrels, though they can’t rule out 2 other explanations.

The allele for melanism may have originated in the common evolutionary ancestor of both species.  Alternatively, the allele for melanism may have arisen first in gray squirrels and was passed on to fox squirrels.  But the most likely explanation is it arose in fox squirrels and was passed on to gray squirrels during interbreeding.

Melanistic gray squirrels are more common in the northern region of their range because the darker coat keeps them warmer when they are outside during winter.  The authors of this study believe the black coat helped gray squirrels colonize newly deglaciated territory following the end of the last Ice Age when the climate was still quite cold.  They didn’t estimate how long ago fox squirrels passed on the melanistic mutation to gray squirrels.  It seems likely this may have occurred a long time ago when both species had recently split from their common ancestor.

Gray squirrels were introduced to England and have now almost completely displaced native Eurasian red squirrels ( Sciurus vulgaris).  Melanistic gray squirrels are replacing the original population of gray squirrels that outcompeted red squirrels in England.

It’s easy to tell the difference between gray and fox squirrels.  The latter are generally twice the size of the former.  A juvenile fox squirrel may be about the same size as an adult gray squirrel, but it is still easy to identify the correct species.  Gray squirrels generally have a white belly, while fox squirrels are solid-colored on the torso and belly.  Fox squirrels often have masks; gray squirrels almost never do.

Reference:

McRobie, H.; N. Moncrief, and N. Mundy

“Multiple Origins of Melanism in Two Species of North American Tree Squirrels (Sciurus)”

BMC Evolutionary Biology   2019

 

 

17,000 Year Old Cougar Crap Found in Argentina

September 7, 2019

When I was researching cougars for my book about 12 years ago and typed the word into a google search, the page was dominated by information about older women who wanted to have sexual relationships with younger men.  This was an unexpected result.  I wanted to learn more about the big cat,  Puma concolor, not about older women seeking younger men.  I see that has changed since then and there are more balanced results with equal representation between the 2 different definitions.

Image result for cougar

Female cougar and young.  I hypothesize Pleistocene adult cougars were spotted.

Cougars were a common large predator throughout most of North America from about 500,000 years BP, until European colonization.  They apparently share a common ancestry with an extinct species of pseudo-cheetah known as Miracinonyx inexpectus.  The cougars that lived in North America then were an extinct ecomorph that was replaced from a population of cougars originating in eastern South America after the great Pleistocene megafauna extinction.  Recently, a cougar coprolite (fossilized feces) was found inside a rock shelter in Catamarca, Argentina.  This region is mountainous and dry, explaining why it was so well preserved.  Scientists used DNA to identify the turd came from a cougar.  They also found DNA belonging to Toxascaris leonine, a parasitic roundworm.  This is the oldest parasitic DNA ever recorded.  Scientists previously thought this species of roundworm was brought to North America inside the guts of domesticated dogs and cats, but this coprolite dates to 17,000 years BP before domesticated pets were brought to the New World.  The species of cat ancestral to the cougar likely brought this parasitic roundworm across the Bering Land Bridge millions of years ago.

Image result for Toxascaris leonina

Toxascaris leonine.

Cougars often ingest roundworms when they eat rodents.  Ingested eggs hatch in the small intestine, and the worms mate and lay eggs that are then passed in the feces.  Rodents consume the eggs and are in turn eaten by the cats and the lifecycle continues.  Adult worms can reach lengths of 3-7 inches.  This species of roundworm can make cats sick, but not as bad as other species that can cause fatal parasitic infections.  T. cati and T. canis  may travel to an animal’s lungs, causing death.  Most kittens are infested with T. cati  through their mother’s milk.  Most survive and naturally get rid of the parasites.  De-worming medications cure infections too.

Reference:

Petrigh, R.; J. Martries, M. Monding, and M. Fugass

“Ancient Parasitic DNA Reveals Toxascaris leonine Presence in Fossil Pleistocene of North America”

Parasitiology 146 (10) 2019

Saber-tooth Cats (Smilodon fatalis) and Dire Wolves (Canis dirus) Did Not Compete as Much as Previously Thought

August 10, 2019

Image result for Charles Knight classic painting of La Brea tar pits dire wolf

This classic painting of dire wolves contesting a carcass with a saber-tooth may give the wrong impression.  A new study suggests their diets didn’t overlap as much as previously thought.

A new study analyzing the isotopic chemistry of tooth enamel from carnivores excavated from the La Brea Tar Pits determined there was not as much overlap in the diets of saber-toothed cats and dire wolves as previously thought.  An earlier study examined the isotopic chemistry from bone collagen of La Brea carnivores, and the results of that study suggested the big 3 carnivores (saber-tooths, dire wolves, and giant lions– Panthera atrox) competed for the same prey items.  However, bone collagen can decay and become contaminated, altering the accuracy of the results.  Tooth enamel is more durable, and scientists believe it provides more accurate results.  This new study concluded both saber-tooths and giant lions were ambush predators that lived in woodlands or forests and fed upon forest-dwelling herbivores such as deer, tapir, and woodland bison.  Dire wolves and coyotes (Canis latrans) lived in more open environments and chased down horses, camels, and plains bison.  The diet of saber-tooths, giant lions, and Pleistocene cougars (Puma concolor) resulted in mathmatical values of isotopic bone chemistry identical to those of modern cougars.  The diet of coyotes changed over time.  During the Pleistocene coyotes scavenged meat from megafauna.  Following the extinction of the Pleistocene megafauna, coyotes evolved toward a reduced size and fed more on bone, smaller animals, and even fruit.  The diets of timber wolves (Canis lupus) and cougars did not change following the extinction of Pleistocene megafauna.

The results of this study did not surprise me.  Saber-tooths and giant lions were built for ambushing prey in the cover of thick vegetative growth found more in woodlands than grasslands.  So of course it makes sense they preyed upon animals in those environments.

Reference:

Desantis, L; et al

“Causes and Consequences of Pleistocene Megafauna Extinction as Revealed from Ranch La Brea Mammals”

Current Biology 29 (15) 2019

Sicily During the Late Pleistocene

May 19, 2019

Over the past few weeks I read The Sicilian by Mario Puzo, author of the famous Godfather series.  He also wrote the screenplays for The Godfather and Christopher Reeve Superman movies.  His early novels were critically acclaimed but didn’t sell, so a publisher suggested he write a novel that focused on the mafia.  In his earlier novels the mafia played just a small role.  He followed this advice only to see The Godfather rejected 20 times before he finally found a publisher.  The Sicilian is every bit as good, and I’m surprised it hasn’t been adapted for the cinema.  Mario Puzo doesn’t describe the nature of Sicily much in his novel.  He does describe the island as quite arid, and he frequently mentions the “red hawks” soaring in the sky.  As a supplement to enjoying this novel I engaged in a brief study of Sicily’s natural history.

Image result for Milvus milvus

The “red hawks” referred to in his book were probably red kites (Milvus milvus), a threatened species.

Sicily in Italy.svg

Location of Sicily.  

Sea level fluctuations during the Pleistocene led to intermittent land bridges connecting Sicily to mainland Europe and as a consequence Sicilian flora and fauna descend from species arriving from that continent.  The location of the island in the Mediterranean Sea moderated climate, and species that disappeared from most of Europe during severe Ice Ages found refuge on Sicily.  The region is now known for mild wet winters and hot dry summers.  Average annual temperatures were likely slightly cooler during stadials.  Myrtle, oak, and cork trees covered lower elevations, while oak-beech forests occupied higher elevations.  Volcanic mountains and abundant rivers vary the landscape.

Species of large animals living on Sicily during the late Pleistocene included bison, aurochs, horse, fallow deer, red deer, roe deer, wild boar, brown bear, cave lion, hyena, wolf, and giant tortoise.  2 unique species lived on the island then–a dwarf elephant (Palaeoloxodon mnaidriensis) and the dwarf Sicilian hippo (Hippopotamus pentlandi).  The dwarf elephant was closely related to the extant Asian elephant.  It weighed just 3000 pounds, and the species also occurred on the nearby island of Malta.  Both the dwarf elephant and the Sicilian hippo became extinct shortly after man colonized Sicily about 14,000 years ago.

Image result for palaeoloxodon mnaidriensis

Artist’s depiction of P. mnaidriensis along with a few swans.  I don’t believe it is drawn correctly to scale, unless this is the depiction of a juvenile.  Dwarf elephants were small but they weren’t this small.

People gradually eroded the quality and quantity of wildlife on Sicily, and they utterly destroyed the natural ecosystems.  Most of the island was deforested during Roman rule, leading to prolonged droughts, and the last wolves were  exterminated during the 1920s.  Though 150 species of birds live on the island, including flamingoes and several species of eagles, many are endangered.  However, the island is home to Nebrodi Mountains National Park where roe deer, wild boar, hares, Eurasian red squirrels, crested porcupines, wild cats, and foxes still roam.  Small towns founded during the Byzantine Empire are scattered throughout the park, and farmers keep rare breeds of horses and black pigs here.  The oldest chestnut tree in the world (more than 2000 years old) grows on Mt. Etna.

I’m going to read a book about the human history of Sicily next and will write a blog article about it when I’m finished.

Reference:

Bofiglo, L. et. al.

“Bio-chronology of Pleistocene Vertebrate Faunas of Sicily and Correlation of Vertebrate Bearing Deposits with Marine Deposits”

Il Quaternario 16 (1BIS) 2003

 

Pleistocene Microfauna Inherited the Earth

April 8, 2019

The biblical passage “Blessed are the meek: for they shall inherit the earth” always makes me think of the late Pleistocene megafauna extinctions.  The passage is part of Jesus’s sermon on the mount and is found in Matthew 5:5, though for some reason Luke omits it.  Most biblical scholars believe the word meek in this passage means powerless, and it represents the slaves and the small powerless Christian sect within the Roman Empire.  A large segment of the Roman Empire’s population consisted of slaves, and the Christian religion appealed to them because of the concept that their miserable lives might be rewarded in the afterlife, if they believed in Jesus.  Ironically, after the Roman Emperor Constantine made Christianity the official religion of the empire centuries later, Christians no longer acted meek–they oppressed all other religions. The late Pleistocene extinctions make me think of this passage because so many powerful animals such as giant lions, saber-tooths, short-faced bears, dire wolves, mastodons, mammoths, ground sloths, and giant bison all disappeared from the face of the earth; but small animals continued to live and were just as common as they’d always been.  Among them are 2 of the smallest mammals on earth–the southern short-tailed shrew (Blarina carolinensis) and the eastern pipistrelle (Pipistrellus subflavus).

Photo of a short-tailed shrew my cats killed last week.

The southern short-tailed shrew weighs between .5-1 ounce.  They hunt in burrows near the surface but also scurry though more permanent burrows located up to 2 feet underground.  They eat half their own weight in food everyday.  Their diet consists of worms, spiders, centipedes, insects, snails, amphibians, and mice.  During winter they can subsist on fruit, acorns, and fungi.   They are smaller than mice but can subdue them with a venomous bite.  Southern short-tailed shrew specimens have been recorded from at least 23 Pleistocene-aged fossil sites, including the Isle of Hope in southeast Georgia.

Image result for Pipistrellus subflavus

Eastern pipistrelle.

The eastern pipistrelle weighs between .1-.3 ounce and is about the size of a large moth.  Their wingspan reaches a width of only about 2 inches.  They feed upon flying insects.  Both eastern pipistrelles and short-tailed shrews navigate in the dark by using echolocation.  Fossil specimens of this species have been found from at least 19 Pleistocene-aged fossil sites including Ladds in north Georgia.

Of course, not all species that inherited the earth are meek.  Man is a notable exception.