Posts Tagged ‘jaguar’

Extinct Subspecies of Pleistocene Jaguars (Panthera onca)

July 12, 2016

The ancestor of the jaguar diverged from ancestral lions and leopards about 8 million years ago.  An extinct species of jaguar (Panthera gombaszoegensis) roamed Eurasia from the early to mid Pleistocene (1.5 million years BP- ~300,000 BP).  This species crossed the Bering Land Bridge over 500,000 years ago and colonized North and South America where it evolved into Panthera onca–the same species still found today from Arizona to Argentina. The jaguar had a much wider range in North America during the late Pleistocene than it does now.  Jaguar bones, dating to this era, have been excavated from sites as far north as Washington state, Oregon, Indiana, West Virginia, and Pennsylvania.  I’ve reviewed the data from these sites in an attempt to determine when jaguars ranged this far north.  I was curious to know if jaguars were able to survive that far north during the coldest climatic phases.  However, these sites are all cave deposits without reliable dating evidence.  Associated faunal remains may be from specimens thousands of years older or younger than the jaguar remains and because climate often fluctuated rapidly during the Pleistocene, they can’t be used as an index for the climatic conditions that occurred when the jaguars lived in the regions.  The ancestor of Panthera onca did negotiate the Bering Land Bridge and Canada to reach its known Pleistocene range.  This region was quite cold even during warmer climate phases, so I believe Pleistocene jaguars were more adaptable to climatic extremes than one might expect.  There’s just not enough evidence to know for sure.

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Both extinct subspecies of Pleistocene jaguars were somewhat larger than present day jaguars.

Pleistocene jaguars were abundant in southeastern North America, rivaling dire wolves (Canis dirus) as the most common large predator in the region then.  Jaguars have been unearthed from at least 18 sites in Florida, 6 sites in Tennessee, 2 sites in Georgia, 1 in South Carolina and another in Alabama.  A jaguar fell into Craighead Caverns in Tennessee and even left paw prints and claw marks in its failed attempt to escape the natural trap.  Complete skeletons of jaguars have been found in other Tennessee caves.  The jaguar that lived in the southeast during the Pleistocene was a distinct subspecies known as Panthera onca augusta.  It was given subspecies status based on its size, averaging 15%-20% larger than the modern jaguar.  Extant jaguars still demonstrate clines (geographical variations in size).  Present day jaguars average larger in the northern and southern limits of their range than they do near the equator.  Larger individuals maintain body heat more efficiently, perhaps explaining the size difference in the cooler parts of their range.  Present day jaguars also grow larger in areas where they can prey on livestock.  So it’s likely the combination of cooler climate and larger prey contributed to the larger size of P. onca augusta during the Pleistocene.

Another extinct subspecies of jaguar lived in South America–P. onca mesembrina.  This population of jaguars also averaged larger than present day jaguars.  A study of P. onca mesembrina genetics determined this clade became extinct in southern Argentina about 12,280 calendar years ago along with other regional megafauna including Darwin’s ground sloth, horse, a llama (Lama gracilis), and a local population of guanacos(Lama guanacoe).  These clades of jaguars and guanacos left no descendents, but other clades of these species recolonized southern Argentina less than 2,000 years later.  The scientists who participated in this study conclude human activities combined with a warming climate phase caused megafauna extinctions here.  Southern beech forests expanded as temperatures and precipitation increased, and the forest encroached on the grasslands.  Herds of grazing animals, forced to migrate greater distances to reach suitable pastures, were more easily ambushed by an increasing human population that now had access to more wild plant foods in the growing forests.  Megafauna survived previous climate changes by altering their patterns of movement throughout the landscape, but some how humans disrupted this during the terminal Pleistocene.

References:

Metcalf, Jessica; et. al.

“Synergistic Role of Climate Warming and Human Occupation in Patagonian Megafaunal Extinctions during the Last Deglaciation”

Science Advances June 2016

Simpson, G.G.

“Discovery of Jaguar Bones and Footprints in a Cave in Tennessee”

American Museum Novitates 1941

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Gran Chaco Megafauna pre-1970 Resembled Pleistocene Fauna of North America

December 14, 2015

The Gran Chaco is a 250,000 square mile eco region encompassing parts of Bolivia, Paraguay, northern Argentina, and southwestern Brazil.  The landscape consists of open palm tree savannah interspersed with thorn scrub on more xeric sites while riverine forests or marshes occur wherever there is water.  The name Chaco derives from the Indian word Chacu, meaning hunting land.  The name suggests various regional Indian tribes regarded the region as a neutral hunting ground, probably because the climate was too arid for productive agriculture.  The region was rich in wildlife, nearly pristine, until 1970 when a major highway was constructed here.  Since then, cattle ranches and irrigated lands have replaced much of the former hunting grounds.

Map of Gran Chaco ecoregion.

Like North America, the Gran Chaco lost its largest but slowest breeding species of megafauna at the end of the Pleistocene.  There were 3 species of elephant-like animals–gompotheres, haplomastodons, and stegomastodons–living here until about 10,000 years ago as well as giant ground sloths, glyptodonts, pampatheres (a plant-eating giant armadillo), liptoterns (a primitive ungulate), horses, and saber-tooths.  However, many of the smaller species of Pleistocene megafauna that became extinct in North America had close relatives still extant in the Gran Chaco region.  The ranges of many of these species no longer overlap with each other because their populations have become fragmented following agricultural development, but an explorer traveling through the region prior to 1970 would have found a fauna very reminiscent of southeastern North America’s during the Pleistocene.  Llamas shared the range with peccaries, 2 species of deer, and tapirs in the Gran Chaco, not unlike the faunal mix of southeastern North America which included 2 species of llama, 2 species of peccary, 3 species of deer, and tapirs.

A remnant population of guanacos, a type of llama, still occurs in the Gran Chaco region.  Guanacos are still common in the Andes Mountains but have been largely extirpated from lowland regions.

The Chacoan peccary (Catagonys wagneri) is a close relative of the extinct flat-headed peccary (Platygonnus compressus), a species formerly common throughout North America.  Scientists only knew the Chacoan peccary from fossil specimens identified in 1930, but then in 1971 western scientists  “discovered” them to be still extant, though the natives were aware of their existence.  This was like discovering an existing population of mammoths.

The Chacoan peccary is closely related to a species of peccary that lived in North America until about 11,000 years ago.  Between 1930-1971 scientists thought they were an extinct Pleistocene species.

There are still many species of edentates in the Gran Chaco.  The edentates were an important component of North America’s fauna during the Pleistocene.  Several species of ground sloths, giant armadillos, pampatheres, and glyptodonts lived in North America then.  The Gran Chaco still hosts 10 species of armadillos, tree sloths, and the giant eater whose raking claws resemble the formidable armament of the extinct giant ground sloths.  The Gran Chaco is likely the center of armadillo evolution.

Giant armadillo

Giant armadillo (Priodontes maximus)

Anteaters are practical. They use their babies to make themselves look bigger and protect themselves.

Giant anteater (Myrmecophaga tridactyla)

Genetic evidence suggests the pampas deer was formerly an abundant species found over a wide area of South America.  Human hunting pressure has greatly fragmented and reduced the population of this species.  Swamp deer live in marshy areas of the Gran Chaco as well.

 

 

 

 

 

 

 

 

 

 

 

Pampas deer (Ozotoceros bezoarticus).  All South American species of deer share a common ancestor with North American white tailed deer.

Two important predators in the Gran Chaco, jaguars and cougars, roamed southeastern North America during the Pleistocene.  The extinction of smaller species of megafauna limited the prey selection of the former, perhaps explaining its recent absence from much of the region.  Studies show the prey items selected by jaguars tend to be larger than those chosen by cougars.

Jaguar and cubs in the Gran Chaco National Park.

The avifauna diversity of the Gran Chaco is astounding as well.  There are over 400 species of birds native to the region, making it one of the richest bird watching sites in the world.  The diversity of wildlife here suggests the region was sparsely populated by humans until very recently.

Big Cats vs. Crocodilians

March 17, 2015

The Mcbrides track cougars (Puma concolor) for the Florida Department of Natural Resources.  Roy Mcbride began tracking Florida panthers in 1972 when there was some doubt over whether this species still existed in state.  (The Florida panther is the same species as the cougar but I prefer using the latter common name.)  A few years ago, the Mcbrides interrupted a cougar feeding upon an alligator it had killed.  They treed the cat and examined the alligator.  Cougars were known to occasionally prey on smaller alligators, but the Mcbrides were surprised at the size of this specimen.  It measured 8 feet, 8 inches–the largest gator ever known to be killed by a cougar.  The cougar had eaten the brisket (chest area) of the gator but was so spooked by the trackers it never returned to the carcass.  The Mcbrides published their discovery in the Southeastern Naturalist.  Below is the 1st page of the 2 page article.

Cats are courageous hunters. Still, it seems unexpected that they would take on such a dangerous choice of prey.  Nevertheless, caimans make up a significant portion of the jaguar’s diet in certain parts of the Amazon jungle.

Jaguar attacks a Yacare Caiman

Jaguar killing caiman.

Leopards and tigers rarely prey on crocodiles, yet they have been recorded slaying them.

Photobucket

This leopard actually dragged the crocodile from the water onto land and killed it.

Youtube video of a tiger killing a crocodile.

A big cat’s strategy for hunting a crocodilian is cunningly effective.  They attack from behind, get a good grip on the reptile, and bite through the braincase, killing it instantly.  They don’t just ambush crocodilians sunning themselves on the riverbank.  The leopard in the above photos dove into the water and yanked the crocodile from its own element.

I wonder if saber-tooths (Smilodon fatalis) ever attacked alligators.  Saber-tooths had a weaker bite force than any species of extant big cat.  Their big canines would have been at risk of breaking, if they tried to bite through an alligator’s skull.  However, they were very powerful and would have been capable of rolling the alligator on its back and slicing through its throat with their fangs.  Jaguars were 1 of the most common large predators in southeastern North America during the Pleistocene and undoubtedly took a toll on alligators here then.

Reference

Mcbride, Roy; and Cougar Mcbride

“Predation of a Large Alligator by a Florida Panther”

Southeastern Naturalist 9 (4) 2010

Extinct Pleistocene Ecomorphs of the Cougar (Puma concolor) and the Timber Wolf (Canis lupus)

April 11, 2014

Genetic evidence suggests all present day cougars found in North America descend from a population of the big cats that lived in northeastern South America 10,000 years ago even though the fossil record shows cougars did live in North America during the late Pleistocene.  Cougar fossils have been found in at least 15 sites in Florida and 2 in Georgia, and they date to between ~130,000 BP- ~12,000 BP.  Yet, cougars that lived in North America during the Pleistocene left no living descendents–apparently they became extinct along with most of the rest of the Pleistocene megafauna.  This seems odd because modern cougars are well adapted to prey on deer and small game that survived the end Pleistocene extinctions, and Pleistocene cougars did not significantly differ morphologically from modern cougars.

The Pleistocene cougar was a large ecomorph.  An ecomorph is defined as a local variety of a species whose appearance is determined by its ecological environment.  Pleistocene cougars averaged 5% larger than modern cougars.  The color of their coat is unknown but it may have been spotted.

Florida Panther & Cub

A Florida panther in captivity.  Cougar kittens are spotted–evidence they evolved from a spotted ancestor.  This particular adult has retained spots.  Pleistocene cougars in North America may have been spotted.  A Florida panther is the same species as a cougar.  It’s now not even regarded as a separate subspecies by most experts.

Rob Klein, the stupid looking asshole on the far right, is the jerk who killed this beautiful animal in Alberta, Canada. (His facial expression is reminicent of those seen on Nazi concentration camp guards during WWII.)  This cougar specimen weighed over 200 pounds.  This unusually large specimen is probably what the average size was for a Pleistocene male cougar.

Even the larger Pleistocene cougars should have been able to survive on white tail deer, a species that increased in numbers when competing megafauna prey species became extinct.  The reason why this cougar ecomorph went extinct is a mystery.  Perhaps this ecomorph was adapted to live in an environment where prey was not scarce, and there may have been a decades long delay before deer populations increased in response to the disappearance of other megafaunal prey species such as horse, llama, and peccary.  Maybe the last surviving Pleistocene carnivores, combined with human hunters, had no other alternate prey and therefore decimated deer populations, so that even this species declined to such low numbers that cougars had too little to eat.  The  cascade effect of losing so many prey species in the environment  almost doomed white tail deer as well because they were one of the few prey species left for predators to feed upon. The disappearance of the cougar from North America suggests a period of time when even white tail deer became scarce.  The genetics study does show that cougars must have been absent from North America for at least 1 breeding generation (about 10 years)  because there’s no evidence the South American founder population ever bred with the North American ecomorphs.  Recolonization of North America by cougars must have been rapid and probably occurred in less than 200 years whenever white tail deer populations rebounded.   Cougar bones have been found in early Holocene-dated archaeological sites–North America was not without cougars for long.

South American cougar populations have greater genetic diversity than those of North America.  There are 5 subspecies of South American cougars compared to just 1 in North America.  (Florida panthers are no longer considered by some to be a different subspecies.)  Florida panthers almost became extinct from inbreeding 20 years ago, but wildlife officials introduced 8 female cougars from Texas, and the population has since tripled.

Genetic studies show a similar history for the jaguar (Panthera onca).  This cat also disappeared from North America and most of South America following the extinction of the Pleistocene megafauna.  It too survived in a refuge located in northeastern South America.  This population eventually recolonized the rest of that continent as well as the southern parts of North America.  Man has probably stymied the further spread of this species.  The last stand refuge shared by cougars and jaguars was probably an area of rain forest uninhabited by man that retained enough game to support a significant population of predators.

The Pleistocene armadillo (Dasypus bellus) has been found to be genetically similar to the modern day 9-banded armadillo (Dasypus novemcinctus).  I hypothesize the modern species is simply a dwarf ecomorph of the larger Pleistocene species.  From a refuge located in South America this dwarf ecomorph has recolonized much of its former range.  This scenario is similar to that of the big cats mentioned above, but it occurred within written historical times. (See https://markgelbart.wordpress.com/2012/08/19/is-the-9-banded-armadillo-dasypus-novemcinctus-a-dwarf-mutation-of-the-pleistocene-species-dasypus-bellus/)

An Alaskan gray wolf.  Modern Alaskan gray wolves are not descended from the wolves that lived here during the Pleistocene.  Those wolves became extinct when the megafauna became extinct.  Instead, modern Alaskan wolves descend from wolves that recolonized the region some time during the Holocene.

The timber wolves living in Alaska during the late Pleistocene were a large ecomorph that also left no living descendents, according to the genetic evidence.  Their anatomical characteristics suggest they were a robust animal well adapted to hunt large now extinct megafauna.  Dire wolves (Canis dirus), common in the rest of North America, never ranged this far north, and the timber wolves living in Alaska then occupied the dire wolf niche.  The Alaskan timber wolf ecomorph became extinct when the Pleistocene megafauna disappeared.  The timber wolves currently living in Alaska descend from wolves that lived elsewhere in North America during the Pleistocene.

Cougars vs. Wolves–the latest updates

The age old war between cougar and wolf has been re-ignited since the latter has been re-introduced to the Rocky Mountains of the United States.  The Teton Cougar Project has recorded 5 cougar kittens killed by wolves.  Meanwhile, a mother cougar killed a yearling wolf and fed it to her kittens.  In Montana cougars have killed 2 adult radio-collared wolves.  In one case they were battling over an elk carcass, and the wolf was left uneaten.  In the other instance the cougar actively hunted, killed, and ate the wolf.

References:

Culver, M. et. al.

“Genomic Ancestry of the American Puma”

Journal of Heredity 2000

Leonard, J.A.; et. al.

“Megafaunal Extinction and Disappearance of Specialized Wolf Ecomorph”

Current Biology 2007

Morgan, Gary; and Kevin Seymour

“Fossil History of the Panther (Puma concolor) and Cheetah-like cat (Miracinonyx inexpectus) in the Florida Pleistocene

Bulletin of the Florida Museum of Natural History 1997

Alexander Von Humboldt’s Journey on the Apure River

September 10, 2013

I wish I could time travel to the Pleistocene and take a boat ride on one of Georgia’s major rivers, such as the Savannah, Altamaha, or Chattahoochee.  I would love to write an account of that experience.    Most people don’t realize how utterly devoid of wildlife the modern world is compared to the time before man decimated nature.  Alexander von Humboldt’s boat ride on the Apure River in 1800 may be the closest real life experience anyone has ever recorded that might be comparable to my wishful journey.  Humboldt traveled throughout the Spanish-claimed colonies of South America between 1799-1804.  For over 50 years after this, he was the sole scientific source of knowledge on the nature of South America.  The Spanish government granted permission to this German scientist to make a scientific expedition through their colonial territories.  This was unusual because the rulers of Spain were influenced by the Catholic Church and didn’t understand the value of science.  Paranoid authorities there assumed foreigners who wanted to travel in their colonies were spies working for enemy governments interested in fomenting revolutions that would result in Spain losing their New World territories. 

The Apure River is located in what today is Venezuela.  At the time of Humboldt’s journey it flowed through one of the more remote regions where few missionary settlements had been established.  The wildlife present then was rich in numbers and diversity.  Many of the same or similar species lived in Georgia during the Pleistocene.  This explains why this part of his journey holds such a fascination for me.

Map of Alexander Humboldt’s scientific expedition from 1799-1804.  This journey provided most of the scientific knowledge in Europe of South America’s natural history for over 50 years because the Spanish and Portuguese governments normally forbade scientific explorations of their colonies.

The Apure River flows through the Apure State in Venezuela.  It empties into the Orinico River.  Alexander Von Humboldt journeyed on this river circa 1800.

Humboldt, and his companion, Bonpland, made the journey with the governor’s brother-in-law, a pilot, and 4 Indian oarsmen.  They used a pirogue made from oxhides stretched over a wooden frame.  The cabin on the boat had a thatched roof.  For food and drink they carried chickens, eggs, cassava, chocolate, oranges, tamarinds, sherry, and brandy.  But the majority of their diet came from animals they hunted including manatees, capybaras, turtles (and their eggs), chacalacas, and currasows–the latter 2 being chicken-like birds.  (Humboldt pronounced manatee as delicious.) They also ate fish both fresh and dried and made into meal.  They used lances more than firearms because the latter often didn’t work in the humid climate.

They suffered from mosquitoes, gnats, and a type of insect that burrowed under their toe and finger nails.  The mosquitoes are so bad in this part of the world that the customary salutation is “How bad were the mosquitoes last night?” instead of “hello” and “goodbye.”  Nevertheless, Humboldt thought the trip was worth the torment just to see all the wildlife.

Humboldt wrote that 4 or 5 caimans, which he referred to as crocodiles, were always in view of the pirogue.  Thick hedges grew alongside the river, interrupted by passages made by peccaries and tapirs that used the same paths daily to access the drinking water.  Neither showed any fear of man.  Both were spotted by Humboldt’s party frequently along with the occasional deer.  Manatees and pink dolphins, known as toninas by the Spanish, swam in the main river channel and in the flooded plains and forests.  Manatees were so abundant that 1 region of the river was called Cano de Manatee.  Clouds of birds flew in the sky, and Humboldt noted the cries of herons, spoonbills, and flamingos were constant.  The presence of pirhanas annoyed Humboldt who wanted to bathe his itchy mosquito bites but feared the vicious “caribe” fish.  When they camped at night, the jungle was alive with the sounds of monkeys, sloths, and jaguars.  Vampire bats fluttered around their camp, and even fed on the blood from Humboldt’s dog.

During the rainy season the Apure River flooded the nearby grasslands turning it into a massive lake.  The floodwaters often rose so fast that horses drowned, attracting caimans and huge flocks of vultures.  Caimans occasionally attacked swimming horses that hadn’t drowned yet.  After the waters receded, some caimans dug holes in the savannahs and hibernated til the floods returned.  One time. Humboldt’s party was startled when a caiman emerged from the ground under a tent where they’d spent the night.  The reptile sprinted through the tent toward the river.  The floods caused some river banks to be covered in sand and silt rather than hedges.  Ten or more caimans often sunned themselves on these beaches.

Herds of 50-60 capybaras could be found everywhere on the Apure.  They were the main food of the surprisingly common jaguars.  Humboldt’s party had numerous encounters with the big cats.  His party saw a very large jaguar that Humboldt said was bigger than any tiger he’d ever seen in a European zoo.  Humboldt said the jaguars here were no danger to man because they had plenty of capybaras to prey upon, though on another river later in his expedition he lost his dog, a mastiff, to a jaguar.  Mastiffs are large dogs, sometimes weighing in excess of 100 lbs.  Nevertheless, 1 particular jaguar viewed it as food.

Capybaras were extremely abundant along the Apure River during Humboldt’s journey, and they helped support very large jaguar and caiman populations.  Two species of capybaras lived along Georgia’s coastal plain rivers during the Pleistocene.

Humboldt walked right by a large jaguar while collecting plants.  It scared the shit out of him, but he walked slowly back to camp, so the jaguar wouldn’t be incited by his flight to attack.  Jaguars were one of the most common large predators in southeastern North America during the Pleistocene.

Humboldt feared that he would become a jaguar’s dinner as he relates in the following account.

I left my companions while they beached the boat and prepared the meal.  I walked along the beach to observe a group of crocodiles asleep in the sun, their tails, covered with broad scaly plates, resting on each other.  Small herons, white as snow, walked on their backs, even on their heads, as if they were tree trunks.  The crocodiles were grey-green, their bodies were half covered in dried mud.  From their color and immobility they looked like bronze statues.  However, my stroll almost cost me my life.  I had been constantly looking towards the river, and then, on seeing a flash of mica in the sand, I also spotted fresh jaguar tracks, easily recognizable by their shape.  The animal had gone off into the jungle, and as I looked in that direction I saw it lying down under the thick foilage of a ceiba, eighty steps away from me.  Never has a tiger seemed so enormous.

There are moments in life when it is useless to call on reason.  I was very scared.  However, I was sufficiently in control of myself to remember what the Indians had advised us to do in such circumstances.  I carried on walking, without breaking into a run or moving my arms, and I thought I noted the wild beast had its eye on a herd of capybaras swimming in the river.  The further away I got the more I quickened my pace.  I was so tempted to turn around and see if  the cat was chasing me!  Luckily, I resisted this impulse, and the tiger remained lying down.  These enormous cats with spotted skins are so well fed in this country well stocked with capybara, peccary, and deer that they rarely attack humans.  I reached the launch panting and told my adventure story to the Indians, who did not give it much importance.”

Reference:

Alexander Von Humboldt: Personal Narrative of a Journey to the Equinoctial Regions of the New Continent

Penguin Books 1995

How Recently did the Jaguar (Panthera onca) Roam Eastern North America?

September 26, 2012

Most people think of the jaguar as a tropical species of cat that lives in deep jungles.  But human persecution is the reason the majority of the world’s remaining population of jaguars lives in remote jungles.  Jaguars can only survive in areas where human density is low.   Ranchers defending their livestock, and people coveting the big cat’s beautiful spotted coat eliminate jaguars from many areas far outside tropical jungles.  The jaguar is probably as adaptable as the Asiatic tiger which ranges into temperate and even boreal forests.  Today, jaguars are known to occur in the deserts of northwest Mexico.  If they can live in jungles and deserts, surely they could adapt to temperate forests as long as suitable prey was available. The Pleistocene fossil record proves that jaguars once ranged over most of North America.  Jaguar fossils have been found as far northwest as Whitman County, Washington and as far northeast as Port Kennedy, Pennsylvania.  Across the southeast jaguar fossils are among the most common of the large carnivores found by fossil collectors.  Along with dire wolves they were probably a dominant predator in the region’s forests for most of the Pleistocene, being more common than the infamous saber-tooth.  So how recently did this dominant predator of the Pleistocene roam North America east of the Mississippi?

Historical range of the jaguar shaded red.  A jaguar was possibly killed 1o miles east of the Mississippi River in 1886. John Lawson wrote that he saw a “tyger” in North Carolina circa 1710.  He knew the difference between a cougar and a jaguar, so I doubt he was mistaken.  The Pleistocene range of the jaguar extended as far north as Washington state and Pennsylvania.  I suspect its Holocene range was also greater than range maps indicate.

I believe Indians gradually overhunted most of the megafauna to extinction between 15,000 BP-~7,000 BP, completely eliminating some species from some regions but haphazardly leaving remnant populations in inadvertent refuges until those too were wiped out.  Jaguars on average take larger prey than cougars, so the decline in megafauna diversity reduced jaguar populations across much of their former range.  Moreover, the Indians directly hunted jaguars for their spotted coat, further reducing their numbers.  Still, there is no ecological reason why jaguars couldn’t have persisted in eastern, particularly southeastern, forests, as long as there was plenty of deer.  In the mid-1960’s a jaguar escaped from captivity and lived in a Florida marsh near Vero Beach for 2 years until a hunter killed the cat.  And deer populations were smaller then than they are today.  Jaguars must have been largely absent from pre-settlement eastern forests because the pre-Columbian population density of Indians was just too high.  However, male jaguars sometimes roam for up to 500 miles.  There was enough wilderness left that a jaguar occasionally could range undetected into the managed woodlands adjacent to Indian towns.  (Indians set fire to the forests regularly to improve habitat for game.) Several artifacts do show that eastern and midwestern Indians did know what jaguars were.

A gorget made out of a conch shell with a jaguar engraving.  This was found in Missouri.

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Jaguar paw prints in a Missouri Cave.  Their age is unknown.

The Missouri conch shell gorget undoubtedly represents a jaguar.  The conch shell, imported from the coast, suggests Indian trade routes from Benton County, Missouri to the sea but, of course, is not proof jaguars lived in Missouri during the time period.  Engraved images of jaguars on 2 bones excavated from a Hopewell burial mound in Ohio date to about 500 AD.  One of the bones was of a human.  They could have been engraved by a person from west of the Mississippi, but perhaps jaguars occasionally wandered into Ohio then.  Two Indian artifacts from Moundsville, Alabama–an effigy pipe and a shell gorget–represent jaguars.  Pottery dating to between 1100 AD-1700 AD found in Florida is engraved with images of a cat.  The engraving is perforated.  The perforations may represent spots, but may also be a design that prevented the pottery from shattering when heated.

John Lawson, an early naturalist explorer (See https://markgelbart.wordpress.com/2012/07/27/john-lawsons-voyage-to-carolina-1700-1711/ ), did write that he saw a “tyger” once.  He never went west of North Carolina, and he knew the difference between a cougar and a jaguar, so I regard this as probable evidence of a jaguar in North Carolina between 1700-1711.  They were rare but present.  Here’s his account:

“Tygers are never met withal in the Settlement; but are more to the Westward, and are not numerous on this Side the Chain of Mountains.  I once saw one, that was larger than a Panther and seem’d to be a very bold Creature.  The Indians that hunt in those Quarters, say, they are seldom met withal.  It seems to differe from the Tyger of Asia and Africa.”

A newspaper article from a June 1886 edition of the Donaldsonville Chief, may be the most recent documented proof of a jaguar east of the Mississippi River.  A big cat had been killing cattle in Ascension Parish, Louisiana which is 10 miles east of the Mississippi River.  Allen Martin and Johnny Walker tracked the big cat down and sicked their dogs on it.  The cat killed 3 of the dogs before one of the hunters “laid it low” with a rifle shot.  They reported that it was 8 feet long and weighed 250 pounds, and they referred to it as an “American tiger,” not a panther.  They were familiar with panthers.  This cat was significantly larger than a panther, or cougar.  The name American tiger was formerly used for jaguar.  Though this probably is an account of a jaguar, curiously there’s no mention of a spotted coat, so it’s not 100% certain.  If it is, this means jaguars persisted in Louisiana 26 years later than those in California which were eliminated there by 1860.  Jaguars continued to range the big thicket region of eastern Texas until about 1902.  An average of 1 was killed annually in south Texas, Arizona, and New Mexico until 1948 when a predator control poisoning program on both sides of the U.S./Mexican border caused their complete extirpation north of the Rio Grande along with Mexican grizzlies and wolves.  Within the last decade jaguars have occasionally ranged into New Mexico, but the xenophobic fence built to keep Mexicans from crossing the border will hinder the jaguar’s return as well.

References:

Daggett, Pierre; and Dale Henry

“The Jaguar in North America”

American Antiquity 39 (3) July 1974

Nowak, Ronald

“A Possible Occurrence of the Jaguar in Louisiana”

The Southwestern Naturalist 17 (4) 1973

See also: https://markgelbart.wordpress.com/2010/07/08/cougars-vs-jaguars/

Jaguar killing a caiman.

Port Kennedy Cave, Pennsylvania

In 1871 workers excavated stone from a limestone fissure they named Port Kennedy Cave, later known as bone cave for all the bones they found.  This cave in near the historic Valley Forge, Pennsylvania.  Cope was the first scientist to identify the fossils found here, but over the past centuries dozens of scientists have studied the specimens because it’s an important Irvingtonian-aged site.  Based on the species of fossils, they’re estimated to be between 1.5 million-300,000 years old which is the Irvingonian Land Mammal Age.  The list of species found here includes Wheatley’s ground sloth, evolutionary ancestor to Jefferson’s ground sloth; Smilodon gracilis which is ancestral to Smilodon fatalis ; the lesser short-faced bear (Arctodus pristinus) ancestral to the giant short-faced bear (Arctodus simus); black bear (Ursus americanus), tapir, peccary, wolverine, skunk, and mastodon.  There were a lot of fossils of smaller animals too, but the excavation at this early date was so clumsy they disintegrated into useless fragments.  Later, groundwater flooded the site, ending the collection of fossils here.  Ehret Magnesium Company dumped asbestos and other debris on the fissure and now it’s buried and lost.  I haven’t been able to determined from information on the web whether recent attempts to relocate the site have been successful.

I mention this site because it’s the northeasternmost known pre-historic occurrence of the jaguar.  Fragmentary remains of a probable jaguar were found in Washington State, making that the northwesternmost locality known of a pre-historic jaguar, but a complete jaguar skeleton dating to 38,600 BP was found in an Oregon cave where a 50,000 year old grizzly skeleton was also found.  That is the oldest grizzly bear fossil known in North America.

Pleistocene Fossil Felid Ratios from the University of Florida Database

January 16, 2012

I followed the same procedure from last week’s study but counted the number of cat fossils in the University of Florida’s Natural History Museum database instead of dog fossils.  I only counted fossils dating from the Rancholabrean Land Mammal Age 300,000 BP-11,000 BP.  The results may be off a little because I was scrolling down while looking at a computer screen.  The results may also be misleading because many specimens may come from just 1 individual.   Nevertheless, I think the data reveals a good estimate of the ratio of species composition during the Pleistocene.

Listed on the University of Florida Museum of Natural History database, I counted 46 jaguar (Panthera onca) specimens, 21 giant panther (Panthera atrox) specimens, 42 saber-tooth (Smilodon fatalis) specimens, 6 scimitar-tooth (Dinobastis serum) specimens, 41 cougar (Puma concolor) specimens, 46 bobcat (Lynx rufus) specimens, 12 river cat (Leopardus amnicola or weidii) specimens and 1 ocelot (Leopardus pardalis) specimen.

The results are similar to those reported by the amateur fossil collectors who post on the fossil forum.  The most significant difference between their reports and database information is abundance of jaguar to saber-tooth abundance.  Amateur fossil collectors claim jaguar fossils are much more common in Florida than saber-tooth, though they do collect the latter and some have found scimitar-tooth specimens as well which are rare in the database.  It may be that the UF database includes a skeleton of a saber-tooth accounting for multiple specimens from 1 individual.

Dire wolves accounted for 64 specimens in my previous study, making them 33% more common, at least in the fossil record than any single species of big cat.  Overall, big cats combined outnumbered dire wolves 156 to 64, making large felines more than twice as common as dire wolves.  Perhaps there was less competition among species of canids, but more among felids.

Pleistocene habitats favorable to various species of big and small cats varied widely.  Mesic oak forests and cypress swamps, which expanded during warm interglacials and interstadials, favored jaguars, river cats, and ocelots.  Jaguars are adabtable enough to live in desertlike brush conditions which were common during cold arid stadials.  Cougars and bobcats thrive in many different types of environments.  The exact environments favored by giant panthers, saber-tooths, and scimitar-tooths is unknown, but it’s likely they were capable of adapting to many different ecotones.

Saber-tooths were evidently one of the most common large carnivores south of the ice sheets in North America.  They were actually no larger than a modern day jaguar.  Saber-tooths never colonized Eurasia, but a distant cousin, the scimitar-tooth had close relatives that did live from the southern tip of Africa to Alaska.  Scimitar-tooths also had longer front legs but these were more slender than those of the saber-tooth.  Their fangs were also smaller and more curved.  In Africa, Asia, and Europe scimitar-tooths became extinct much earlier than saber-tooths did in America.  I suspect they never learned to fear man, explaining their earlier extinction.  I suggest fanged cats didn’t often back down from anything.  Scimitar-tooths probably colonized southeastern North America during stadials when grasslands expanded due to dry climate which in turn caused an increase in the populations of ungulates. 

Giant panthers probably resembled large maneless lions.  True lions did live in Alaska and across Eurasia.  But south of the ice sheets in North America, the common ancestor split into 2 different species–Panthera atrox and Panthera onca.

8 cat 10 Biggest Cats in the History

This image comparing Pleistocene jaguars with modern jaguars may be a slight exaggeration, but jaguars did grow bigger during the Pleistocene because they preyed on larger mammals and had more competition among carnivores.

I’ll write more about the presence of margays and ocelots in Pleistocene Florida in my next blog entry.

Here are some related articles about big cats from my archives.

“Panthera atrox! What Kind of Cat was it?”– https://markgelbart.wordpress.com/2010/07/28/panthera-atrox-what-kind-of-cat-was-it/

“Why did fanged cathttps://markgelbart.wordpress.com/tag/saber-tooth/s have sloping backs and large forelimbs?”–

“Two new studies of saber-tooths.”– https://markgelbart.wordpress.com/2011/07/08/two-new-studies-of-sabertooth-smilodon-fatalis-anatomy/

“Cougars vs. jaguars”–https://markgelbart.wordpress.com/2010/07/08/cougars-vs-jaguars/

When Ice Age Georgia Became Desert-like

November 7, 2011

During the Last Glacial Maximum when much of the world’s water became locked in glacial ice sheets, the climate in southeastern North America was much drier.  Small rivers dried up and larger rivers shrank in size and became braided in pattern so that they were like long chains of disconnected channels.  The exposed river sands blew into eolian dunes like those from this picture of a modern Mojave desert dune.  Ironically, during these cold stadials, as the climate became dry in southeastern North America, precipitation increased in the southwest, so that it was quite lush there.  

Dry climate phases have periodically struck southeastern North America many times over the past 5 million years.  Scientists know little about the paleoecological details of most of these phases because there’s not much available data.  But thanks to one study, they do have a relatively clear understanding of the ecological composition of south central Georgia from 30,000 years BP-25,000 years BP.

Scientists took a 17 foot core of sediment from a peat deposit next to Sandy Run Creek on Warner Robins Air Force Base which is located near Macon, Georgia.  They radio-carbon dated the sample and counted the pollen grains to determine what the environment was like during this time period.  This was a time of glacial expansion and as much of the earth’s water became locked in ice, less moisture in the atmosphere was available as precipitation.  Southeastern North America experienced extended droughts causing the water table to drop.  Water flow on major rivers was greatly reduced creating braided river patterns and this turned the rivers into chains of disconnected channels interspersed with islands and sandbars.  In some cases small rivers completely dried up, exposing great quantities of river borne sand.  Atmospheric conditions caused by the glacier to the north spawned frequent westerly and southwesterly winds that blew this river borne sand across the landscape forming huge eolian sand dunes.

Today, vegetation has taken root and holds down the eolian sand dunes that formerly rolled across Georgia’s landscape during cold arid stadials.  Now, scrub turkey oak and longleaf pine covers the Ohoopee sand dune in Georgia.  The sandy soil is of poor quality and not enough litter accumulates to foster fire, allowing scrub oak to become more common than pine. Photo is from google images.

Photo from google images of the Ohoopee River.  This and other small rivers dried out during cold dry climate phases.  Instead, small pools of water appeared sporadically in the river bed.  The scene would have resembled modern African water holes.

The evidence from the pollen composition of the Sandy Run Creek peat core indicates a much different landscape than occurs anywhere in Georgia today.  While eolian sand dunes rolled to the east of reduced or even completely dried rivers, lightly wooded grasslands predominated over much of the environment.  Here and there were groves of pine with some spruce.  (The species of pine isn’t known, but my educated guess is they were a mixture of northern and southern species, probably shortleaf and white.  The species of spruce was likely the extinct Critchfield’s.) Oaks and other deciduous trees clung to the vicinity of shrinking water holes found along the braided rivers.  Pine composed 39%-75% of the pollen, while oak only made up 12%. Grass and coniferous trees require less water than hardwoods, and are less prone to physical damage from frequent wind, explaining why they were more abundant.  Scientists found no charcoal in the part of the core dating from 30,000 BP-25,500 BP–evidence wild fires were a rarity.  This suggests a thinly vegetated environment where combustible material such as dead wood didn’t accumulate.  Moreover, lightning storms that ignite fires were uncommon.  Charcoal is present in the part of the core dating from 25,500 BP- 25,000 BP, perhaps indicating a weak interstadial with more frequent electrical storms.

Grass-eaters such as mammoths, horses, and bison likely predominated in this kind of environment along with the occasional Harlan’s ground sloth which preferred more open environments than its cousin–Jefferson’s ground sloth.  Badgers, thirteen-lined ground squirrels, and perhaps jackrabbits colonized the region then.  Animals that prefered more forested environments were restricted to riverine woods.  Game accumulated around shrinking water holes and this probably contributed to erosion of riverbanks which in turn added sediment to the formation of eolian dunes.  These congregations of herbivores attracted predators such as dire wolves, jaguars, and saber-tooths.

You can buy this illustration of flat-headed peccaries (Platygonus compressus) from the website engraved on the image.  This kind 0f peccary was probably pretty common during dry climate phases in the south.  They ate tough spiny vegetation such as cactuses.  They lived in large herds that were probably aggressively defensive, much like modern white-lipped peccaries.

Photo of a jaguar in Arizona.  Jaguars inhabit many different types of environments such as deserts and rain forests.  They were adaptable enough to probably have been the most common large cat in southeastern North America during stadials and interstadials.

Photo of a hog-nosed skunk.  Today, this species lives in Mexico and the southwestern United States.  Fossils of hog-nosed skunks have been found in Georgia and Florida.  They must have colonized the region during dry climatic phases.

There’s no sediment in the Sandy Run Creek peat core dating from 25,000 BP-13,000 BP.  Scientists call this an erosional unconformity.  They believe the creek changed coarse or flooded and washed away all the sediment accumulated during this time period.  This is consistent with what we know of the environmental changes that occurred during this time period.  About 16,000 years BP the Boling-Alerod interstadial began.  The Laurentide Glacier rapidly commenced melting, putting more moisture in the atmosphere and precipitation increased.  The water table rose and so did river flow.  Rivers no longer consisted of braided patterns, but instead meandered to an even greater degree than they do today, forming scroll-like sandbars.

Satellite view of a meandering river with scroll bars.  During the Boling-Alerod Interstadial beginning about 16,000 years ago, precipitation increased, causing rivers to meander even more than they do today.  This new river pattern formed frequent scroll bars. a kind of sand bar created when the meander of a river continously shifts and leaves ridges parallel to the meander.

Though sand dunes no longer rolled across the landscape during the interstadial, there’s evidence of considerable sandbar formation.  Scroll bar formation suggests a dry season/wet season climate.  Autumn and early winter were mostly dry and river levels fell, exposing sand bars.  But existing atmospheric factors caused heavy precipitation in late winter, spring, and early summer.  Warm tropical fronts collided with cold parabolic winds originating from the still extant glacier.  This spawned great snow, ice, and rain storms that caused massive floods.  Rivers shifted.  Occasional tropical storms compounded this trend.

The pollen record of the Sandy Run Creek peat core, which picks up again about 13,000 BP, demonstrates a much different environment from that of 25,000 BP.  From 13,000 BP-11,000 BP there was a sudden cooling trend known as the Younger Dryas.  The paleobotanical evidence, however, still shows the influence of the previous interstadial warming trend.  A cool, moist, open oak woodland prevailed in south central Georgia during this time period.  Oak pollen doubled from 12% to 24% while pine pollen declined to just 7%.  Critchfield’s spruce and fir were still present but so were hickory and beech–a clue that temperatures were moderate but remained cooler than those of today.  An increase in charcoal is evidence that vegetation was thicker than it had been in the previous time period because now there was more forest litter available as tinder for fires.  And the frequency of lightning storms, which ignites fires, increased.  A northern species of alder, a type of shrubby birch that no longer occurs in Georgia, commonly grew in abandoned, dry, river meanders.  Grasslands still existed to a greater extent than occurs naturally today but had declined in abundance compared with 25,000 years BP.

Scientists use an interesting method to help determine changes in the density of vegetation over time.  They add exotic pollen to cores of sediment.  In this study of the Sandy Run Creek sediment core, they added a known quantity of eucalyptus–a species which didn’t live in North America during the Pleistocene.  The ratio of eucalyptus to native pollen was high during the time period of 30,000 years BP-25,000 years BP–evidence vegetation density was low.  Conversely, the ratio of introduced eucalyptus pollen was low during the time period between 13,000 years BP-11,000 years BP–evidence the vegetation density was higher.

The change to a more moist wooded environment favored higher populations of mastodon, deer, long-nosed peccary, bears, beavers, tree squirrels, and cottontails.

References:

Lamoreaux, Heidi; George Brook, and John Knox

“Late Pleistocene and Holocene Environments of the Southeastern U.S. from the Stratigraphy and Pollen Content of a Peat Deposit on the Georgia Coastal Plain”

Paleogeography, Paleolimnology, and Paleoecology 2009

Leigh, David

“Late Quaternary Climates and River Channels of the Atlantic Coastal Plain, Southeastern USA”

Geomorphology 2008