Big Cats vs. Crocodilians

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 killing caiman.

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

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)

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.

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

Cougars, House Cats, and Berserkers

Cougars are capable of breeding year round.  This is evidence they evolved from an ancestor that lived in a tropical climate.  Other large mammals living in temperate climates breed in late fall and early winter so they can give birth in spring and early summer when food is more abundant.   Deer and elk fawns and bison calves build a layer of fat during summer that helps them survive harsh winters.  But the same isn’t true for cougars.  Cougars give birth year round, and scientists have found no difference in survival rates among kittens born during different times of the year.  A kitten born during a harsh winter in the Rocky Mountains even has some advantages.  The mother doesn’t have to travel as far to find food because there is an increase in the number of prey animals weakened from starvation.  Animals such as elk and deer also struggle in deep snows, making them easier to kill.  Moreover, bears, a dangerous threat to kittens left alone by hunting mothers, are hibernating and not foraging.  There was no advantage for cougars to evolve the trait of breeding only during certain times of the year. Photo from the December 1994 issue of Natural History Magazine showing a cougar killing a mountain goat. The illustration of the larger cat is an artist’s rendering of the middle Pleistocene cheetah–Miracinonyx inexpectus.  The smaller cat in the picture is a modern day cheetah.  Cougars evolved from the ancestor of the middle Pleistocene cheetah, known as Studer’s cheetah–Miracinonyx studeri.  Studer’s cheetah had characteristics intermediate between a cougar and a cheetah.  It could run faster than a cougar, but was larger, stronger, and more powerfully built than a modern cheetah, and therefore could climb trees and ambush larger prey.  North American cheetahs had retractible claws, a characteristic modern cheetahs lack. Cougars were a common predator in the southeast during the late Pleistocene.  There is plenty of fossil evidence of cougars from Georgia and Florida.  Fossil evidence of cheetahs comes from middle Pleistocene sites in Florida, but by the late Pleistocene American cheetahs were restricted to the western part of the continent. The biggest threat to cougar kittens is adult male cougars.  There is an evolutionary advantage for male cougars that kill cougar kittens.  Male cougars that kill the offspring of other males can then mate with the females that go into heat following the loss of their kittens.  This increases the chance his genes will continue into the future.  A male cougar that covers the most territory, kills the most kittens, and mates the most often is generally the fittest, most capable individual in the area.  Baby-killing appears to be a universal trait among most, if not all, cat species, including the house cat (Felis domestica). Lone Ranger, my favorite cat.  She was the runt of a litter.  She adopted me during the dead of winter about 2.5 years ago.  Despite her small size, she bravely drives off the much larger tom cats who try to kill her kittens.  Nevertheless, she has never successfully protected her kittens from the persistent homicidal males for longer than 6 weeks.  Oddly enough, she willingly mates with the tom cats days after they kill her babies. Currently, two female cats have adopted my yard as their home base.  Hissy-fit was one of a whole slew of cats that I think belonged to a former neighbor two houses from mine.  The underfed, half-feral cats swarmed to my compost pile whenever I threw junk in there they considered edible.  I began to pick favorites from this group and fed them real food.  Eventually, cars, dogs, and disease thinned the number of cats, but Hissy-fit, my least favorite, still lives.  She is not a friendly cat–she hisses at me, and she used to lean away (a hint not to pet her) even as I fed her, though after several years of socialization, she now tolerates being petted.  She rarely makes the meow vocalization, but instead hisses, even when she’s seemingly not angry.  She gave birth to my favorite cat–Lone Ranger, the lone survivor from that litter.  She left Lone Ranger for long periods of time on our front door step one cold December when the kitten was a few weeks old.  I took the time to properly tame her, and the first time I let her play with a ball of yarn, she purred.  Lone Ranger is a gentle, affectionate cat, but she is a slut.  In 2 1/2 years she’s already had 3 litters.  Despite being a runt, she’s always very courageous when defending her kittens from the much larger tom cats that persistently try to kill every kitten in their territory.  When she’s protecting her own kittens, she even drives her own mother from the yard.  Hissy-fit just gave birth to another kitten, and Lone Ranger is helping her defend it.  The two cats worked as a team to defend a single newborn kitten last summer as well but were ultimately unsuccessful.  Tom cats are relentless and merciless. I noticed a peculiarity last year.  Lone Ranger went into heat and mated with a tom cat I suspected of killing and eating her kittens a few days earlier.  Imagine if a human mother would agree to have sex with a man who killed and ate her babies.  It seems unthinkable, bizarre.  Yet, in human history similar scenarios are not that uncommon.   Vikings, aided by a berserker, raiding a village.  Berserkers were psychotically violent  men used as shock troops.  In peacetime they were bullies who challenged rich men to death duels.  After killing the wealthy man they took his land, livestock, and women.  Geneological records show berserkers did leave more descendents than other men.  Humans are not so different from cats afterall. The Vikings were known for their violent culture, but within this society were men who were the most violent of the violent–the creme` de la creme`, so to speak.  These insanely violent men were called berserkers.  Historians suspect they may have been psychopaths or schizoids immune to any semblence of conscience.  Viking kings used them to help intimidate the monasteries and villages they raided and looted.  Berserkers were a great help when they were on a raid, but at home during peaceful intervals they posed a problem.  They often challenged rich men to death duels.  I doubt wealthy men really had a viable way of opting out.  After killing the wealthy man, the berserker confiscated his land, livestock, and women.  The Vikings considered women little more than livestock.  The Viking wives and concubines had no choice but to submit to sex with the psycho who murdered the man they probably loved.  Berserkers were probably indifferent to the fate of babies and toddlers, but I’m sure infanticide did happen.  Berserkers infamously killed people who disturbed their sleep, and crying babies will do that. Incidentally, I don’t think many of the hundreds of google images of berserkers are historically accurate.  They’re always depicted as uber-muscular giants.  I believe berserkers were ordinary looking men.  It doesn’t take much muscle to kill a man with a sword or battle axe.  Instead, it takes ferocity and a lack of inhibition to murder.  The inhibition against killing other human beings is so surprisingly strong, that military experts extimate only 15% of U.S. combat infantrymen fired their rifles during World War II, even when they were being attacked.  The modern military specially trains men to overcome this inhibition, but still only achieve a 90% success rate at getting combat infantrymen to fire their weapons against other human beings in combat. Vikings were not the only culture that approved of killing other men and taking their women.  Many American Indian tribes massacred enemy villages with the exception of breeding-age women which they enslaved.  The Mongols under Ghengis Khan wiped out men and spread their seed among the surviving women to such an extent that today a significant percentage of the population in Eurasia has Mongol ancestry.  Some South Pacific Islanders not only killed their enemies but ate them as well.  Cannibalism most frequently occurs on crowded islands where there is a shortage of big game animals, and the people get tired of eating fish.  Overcrowded environments are also a contributing factor.  Perhaps, if overpopulation of the world approaches that of South Pacific islands, cannibalism might become as common for humans as it is for cats.  Maybe the movie, Soylent Green (based on the book, More Room, More Room) was a prophecy. Reference: McAllister, Peter Manthropology St. Martin’s Press 2009