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I have a special treat today. I am pleased to announce our first guest post on paleoaerie. John Svendsen found a set of puma fossils when he was in high school. Today, he shares with us what he has learned about them since that time.
“Masters of stealth, they seldom step from the shadows.”
For many years people have reported sightings of mountain lions and pumas in Arkansas yet the Arkansas Game and Fish Commission has repeatedly disputed such claims. Rather the AGFC believes that any such sightings are simply of feral mountain lions released from captivity that should be shot on sight. Why would the AFGC deny the obvious – that living, breeding mountain lions can be found in the state? As noted by Bryan Hendricks (2009), if the AGFC acknowledges the presence of a sustainable population of wild mountain lions in Arkansas, then it will be compelled to draft a management plan to assure their survival. That means the agency will have to devote money and manpower to compile a population estimate, and then hold meetings to get public input for management options. By virtue of the mountain lions endangered status, a management plan would likely seek to increase or maintain its population – obviously, deer and turkey hunters and livestock farmers would feel at risk having this predator protected by law and would seek litigation or legislation to assure that they can continue to kill mountain lions on sight.
Fortunately there was a time tens of thousands of years ago when mountain lions roamed the state without fear of man. This ancient pre-historic cat roamed the hills and savanna of North America for millions of years in the company of dire wolves, saber-tooth tigers, giant sloths, peccaries and cave bears. Just as these mammals became extinct so did the mountain lion and by the late Pleistocene (approximately 10-12,000 years ago) no mountain lions survived in North America. Fortunately a few mountain lions from South America migrated northward and reestablished living populations throughout much of North America. The mountain lions we see today in Arkansas are the ancestors of this small migrating band from South America.
The mountain lion, known scientifically as Puma concolor, occupies a vast range of ecological zones as diverse as desert, tropical rain forest and alpine steppes (Kurten, 1976). Cats such as P. concolor are poorly represented in the fossil record and taxonomic research on felids is somewhat incomplete. Much of what is known about their evolutionary history is based on mitochondrial DNA analysis and still there are substantial confidence intervals in suggested dates and lots of room for error (Culver et. al, 2000). We do know however that pumas come from a very long line of evolution with episodic bursts of development and diversification that can be traced 40 to 60 million years ago through the late Tertiary period.
These prehistoric creatures are large cats with powerful bodies. Males can weigh 250lbs. (103 kg) with a length of 4.5 feet and a 3 foot tail. It is the second largest cat in the Americas, after the Jaguar, and it is the fourth heaviest cat in the world, after the Tiger, Lion, and Jaguar. It is a solitary cat and rarely is seen in the presence of other cats except during breeding and the raising of a litter. It is an apex predator and is specialized for the task: binocular vision, acute sense of smell and sight, retractable claws, strong canine teeth and masseters, and powerful forearms and legs allowing it to leap 40 feet, jump 15 feet high and pounce from a height of 5-story building. Few animals are capable of outrunning, alluding or surviving a puma attack — fortunately they prey chiefly on the weak and injured and thus strengthen the gene pool of those on which they prey.
Puma fossils are rare in the fossil record of Arkansas and have only been identified from: Conard Fissure and Svendsen Cave (see Figure 1). Conard Fissure is a geologic feature in Northern Arkansas where a deposit of Pleistocene fossils were discovered in 1903 when Waldo Conard was searching through fissures and crevices on his land in search of lead. In one of these fissures he found a “bone mine” with thousands of bones preserved in limestone – thirty-seven genera and fifty one species, of which nearly half are extinct. The original excavation of the fissure was performed by Barnum Brown, the initial discoverer of Tyranosaurus rex, and yielded an assortment of small animals and rodents but also larger mammals including peccary, deer, bear, wolves and foxes. This entombment of a wonderful assemblage of mammal is accounted for by the fact that the fissure long remained open and was inhabited in the late Irvingtonian (240,000-300,000 years BP) by many carnivorous animals.
Svendsen Cave yielded the remains of a puma following its discovery in 1974 by two young spelunkers, John Svendsen and Ola Eriksson who were still in high school at the time (Pluckette, 1975). The cave is developed in dolomitic limestone of the Everton Formation and contains over a mile of mapped passage and three stream systems. The skeletal remains were encased in a travertine ledge only 500 feet from the entrance of the cave (see Figure 3) but passage to the remains included a low strenuous crawl and squeeze, a siphon and two climbs. The puma is presumed to have entered the cave from an entrance now unknown and may have been washed to the depositional site.
Svendsen Cave proved to be a marvelous find as the remains were chiefly intact and materials that were recovered included: partial skull with teeth, partial left mandible with teeth, left humerus, scapula, ribs, and vertebrae (see Figures 4-6). No exact date can be assigned to the Svendsen puma albeit antiquity is evident given mode of occurrence and lack of metastable materials in the skeletal remains. At the depositional site, the bone-bearing travertine is undergoing dissolution and the sediments are being removed by a nearby stream. Thus a climatic regimen of less than the present level of precipitation which allowed formation of the travertine ledge is indicated for the cave area during deposition of the puma (Pluckette, 1975). Given the dimensions of the dentition, mandible and humerus obtained from the site a dating of the Middle Pleistocene, Ionian stage (781 to 126 thousand years ago), is presumed albeit the fossils could be much older.
P. concolor is still a resident of Arkansas. In most of North America P. concolor is currently classified as an endangered species and protected, whereas in Arkansas it is currently legal to shoot and kill P. concolor upon sight as the Arkansas Game and Fish Commission has declared, “All cougars (mountain lions) in Arkansas are considered to be escaped pets or the feral progeny of escaped pets and hence it is legal to kill such animals.” The future of this magnificent big cat lies at the mercy of people who must preserve its natural environment and allow it free passage.
Brown, B. 1908. The Conrad Fissure, a Pleistocene bone deposit in northern Arkansas; with descriptions of two new genera and twenty new species of mammals. Am. Mus. Nat. Hist. Mem. 9: 155-208.
Hendricks, B. 2009. “Arkansas sportsman: AGFC not lying just avoiding furball over big cats.” Arkansas Democrat-Gazette. Feb. 8, 2009.
Johnson, W.E., Eizirik, E., Pecon-Slattery, J., Murphy, W.J., Antunes, A., Teeling, E. and O’Brien, S. J. 2006. The Late Miocene radiation of modern Felidae: A genetic assessment. Science 311:73-77
Kurten, B. 1965. The Pleistocene felidae of Florida. Bull. Florida State Mus. 9(6): 215-273.
Kurten, B. 1976. Fossil Puma (Mammalia: Felidae) in North America. Netherlands Journ. of Zoo. 2694): 502-534.
O’Brian, S. J., and Johnson, W. E. 2005. Big Cat Genomics. Ann. Rev. Genomics Hum. Genet. 6: 409-29
Pluckette, W. L. 1975. An occurrence of the Puma, Felis concolor, from Svendsen Cave, Marion County, Arkansas. Ark. Acad. Of Sciences, Vol. 29, p. 52-53.
Turner, A. 1997. The Big Cats and Their Fossil Relatives: an Illustrated Guide to Their Evolution and Natural History. New York: Columbia University Press.
Young, S.P. and Goldman, E.A. 1946. The puma, mysterious American cat. Am. Wildlife Inst. 358 p.
On Monday I posted a picture of a tooth from an animal that is a famous California resident, although is not generally considered an Arkansan. Were you able to figure it out?
The tooth is a canine from a Smilodon, the saber-toothed tiger (although not actually related to tigers). Smilodon fossils have been found in a few caves in the Ozarks of northern Arkansas, most notably Hurricane River Cave and the Conard Fissure (the Conard Fissure was excavated by Barnum Brown for the American Museum of Natural History, who also did a lot of famous dinosaur digs for them in the Rockies) . Originally, they were described as having come from two different species of Smilodon: S. fatalis and S. floridensis. Smilodon fatalis, sometimes called S. californicus, is well-known from the La Brea Tar Pits in California, although has been found throughout much of North America and Pacific coastal areas of South America. Smilodon floridensis was known primarily from, unsurprisingly, Florida and neighboring states. However, these days most researchers view them all as the same species, so just Smilodon fatalis. There are two other recognized species. Smilodon populator lived in South America and was bigger, with a few hundred more pounds on S. fatalis. Smilodon gracilis was half the size of S. fatalis and lived earlier than either of the other species, and is considered by some to be ancestral to them.
Smilodon fatalis is the quintessential Ice Age predator. It appeared about 2.5 million years ago and only died out about 10-13,000 years ago, so it may have been possible that Smilodon preyed upon early humans, at least along the Pacific coastal areas. It was a big, burly cat weighing up to 600 lbs. with heavily muscled forelimbs. Of course, it is best-known for its 7” long, serrated canines, thus the name Smilodon, meaning “carving knife tooth”. Smilodons were part of a group known as Machairodontinae, a subfamily within Felidae known as the “dirk-toothed cats.” These long teeth necessitated a jaw that could swing extraordinarily wide. Smilodon was specialized for killing large prey, such as bison, horses, and young mammoths and mastodons. Much debate has centered on how it dispatched its prey, with depictions of a Smilodon burying its canines in the skull or eviscerating its prey. However, more recent studies have indicated the canines were too fragile to withstand such treatment or couldn’t get a sufficient bite to properly tear into the abdomen. It is thought instead that Smilodon used its powerful forelimbs to stun and restrain the prey until it could bring its canines into play with its powerful neck muscles to slash the throat and cut the major arteries, causing the animal to bleed out quickly. They were not fast runners, preferring to attack from ambush, staying hidden within the vegetation of the forests and bushlands it preferred to live in.
Youngsteadt J.O., 1980: A saber toothed cat smilodon floridanus from hurricane river cave northwest arkansas usa. Nss Bulletin: 8-14
B. Brown, The Conard Fissure, A Pleistocene Bone Deposit in Northern Arkansas…,Memoirs of the American Museum of Natural History, Vol IX, Part IV, February 1908.