Croc Ancestor 'Carolina Butcher' Ruled Before Dinos

A reconstruction of the "Carolina Butcher," Carnufex carolinensis.


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Crocodiles Just Wanna Have Fun: Photos

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Crocodiles are fun-loving, finds a new study on the toothsome predators. Since play is associated with intelligence, the findings, published in the latest issue of the journal Animal Behavior and Cognition, suggest that crocodiles are smarter and much more social than previously thought. They also appear to have a romantic side. Author Vladimir Dinets of the University of Tennessee, Knoxville, believes that croc "courtship might involve elements of play that are often difficult to recognize as such. I observed and photographed a pair of adult Cuban crocodiles at Zoo Miami (shown here) performing a particularly unusual behavior at the time of courtship: the female would get on the back of the larger male, and he would give her a few rides around the pool." Dinets has also seen young crocodiles enjoying piggyback rides offered by larger adults. Video: Fossil Find Reveals Ancient 900-Pound Crocodile

Vladimir Dinets

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Dinets has studied crocodiles for over a decade, during which time he has long-suspected that they play -- and enjoy it. For the new paper, he compiled his own observations of crocodiles playing. He added these to other published and unpublished reports. The survey found crocodiles engage in all three main types of play known in the animal kingdom: locomotor play, play with objects and social play. While such activities offer benefits, such as forging social connections and facilitating learning, the immediate reward is pure pleasure. Prior research conducted by renowned animal behaviorist Jonathon Balcombe concluded that crocodiles do feel pleasure. The feelings arise via the release of happiness-promoting chemicals like the neurotransmitter dopamine. This sunning croc appears to be feeling no pain. Trio of Huge Crocs Ruled Europe's Jurassic Waters

Judd Patterson, National Park Service

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Crocodiles are incredibly strong and toothy predators, so most other animals -- including humans -- can serve as prey for them. Crocodiles, however, have been seen playing with other animals, according to Dinets. Crocs have even forged long-term bonds with species that they might otherwise eat. Most Amazing Animal Friendships: Photos

Adam Jones, Wikimedia Commons

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Like dogs, crocodiles will sometimes play with their food. For example, they may spend time investigating bones, chewing on them, and tossing them around, long after the meat on them has been gnawed off.

Ad Meskens, Wikimedia Commons

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Alligators enjoy playtime too, Dinets discovered. He spotted this American alligator resting after a "bout of play with a stream of water" at the Saint Augustine Alligator Farm Zoo Park in Florida. As for a human standing under a shower, the falling water likely offered a nice massage on the alligator's body.

Vladimir Dinets

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Dinets has seen crocodiles playing with flowers on several occasions. He snapped a Cuban crocodile at Zoo Miami in Florida (left) playing with Bougainvillea flowers. He also photographed a West African dwarf crocodile playing with the same type of flower at Madras Crocodile Bank in Tamil Nadu, India. It could be that the color and texture of this particular flower is somehow appealing to crocodiles. Spring Flowers on Display: Photos

Vladimir Dinets

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Prior research conducted by Gordon Burghardt at the University of Tennessee, Knoxville, found that crocodiles are more likely to play under certain circumstances. "The behavior is initiated when the animal is adequately fed, healthy, relaxed, and free from stress, such as predator threat, harsh microclimate, (and) social instability, or intense competing systems, such as feeding mating (and) predator avoidance," Burghardt wrote. It could be that most, if not all, social animals enjoy some form of play. The conditions described by Burghardt could apply to humans, dogs, cats, birds and countless other species that only play when they are free from stress and predators.

David Tribble, Wikimedia Commons

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Food provides its own reward, but crocodiles seem to enjoy food games too. This individual, for example, lunges toward a hotdog skewered on a twig. The behavior is probably comparable to a dog or cat eagerly chasing after a yummy treat. Crocodiles like toys too, according to Dinets. "Hundreds of thousands of crocodilians are now kept in captivity in zoos, commercial farms and breeding centers set up for endangered species," he said. "Providing them with toys and other opportunities for play makes them happier and healthier."

James DeMers, Pixabay

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Crocodiles are among the oldest animals on earth, since their ancestors were around at least 200 million years ago. Modern crocodiles date back to around 80 million years ago. These ultimate survivors used to exist around—and eat—non-avian dinosaurs, which they have clearly since outlived. So long as their habitats offered comforts and food, crocodiles were probably enjoying playtime for tens of millions of years before the first humans even appeared.

Mark Witton, University of Portsmouth

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While close encounters with crocodiles are not advised, Dinets said that there are rare cases where crocodiles have bonded so strongly with people that they have become playmates for years. The crocodile shown in this image has had regular human contact, and therefore does not seem to mind the close proximity of people, one of which is nearly sitting on the croc. Dinets described an instance where a man rescued a crocodile that had been shot in the head. The croc recovered and did not seem to forget the kindness of his human savior. Dinets said, "The croc would swim with his human friend, try to startle him by suddenly pretending to attack him or by sneaking up on him from behind, and accept being caressed, hugged, rotated in the water and kissed on the snout." He added that the two played happily together every day until the crocodile died 20 years later.

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An enormous crocodile ancestor with blade-like teeth walked on two legs and was at the very top of North America's food chain 231 million years ago, according to a new study.

Named "Carolina Butcher" ( Carnufex carolinensis ), the newly discovered toothy beast reveals that predecessors of today's crocodiles -- crocodylomorphs -- were top predators in North America prior to the reign of dinosaurs.

Carolina Butcher, described in the latest issue of the journal Scientific Reports, lived up to its horror movie-style name.

Think modern crocodiles are terrifying? How about a 16-foot-long, nearly half a ton sort-of-crocodile that was so tough it even outlasted the mass extinction of 60 million years ago. Laci has more details on this beast from the land of the lost.

" Carnufex lived in what is now North Carolina around the time the supercontinent Pangea was breaking apart," lead author Lindsay Zanno told Discovery News. "The skull of Carnufex is slender and long-snouted with dozens of blade-like teeth. For all practical purposes, this was an animal skillfully adapted for slicing flesh from the bones of its victims."

Zanno is an assistant research professor at North Carolina State University and director of the Paleontology & Geology Research Laboratory at the North Carolina Museum of Natural Sciences. She and her colleagues recovered the remains of Carolina Butcher from the Pekin Formation in Chatham County, North Carolina. When the crocodylomorph was alive during the beginning of the Late Triassic, this area was a wet and warm equatorial region.

The researchers created a detailed 3-D model of Carolina Butcher's skull using a high-resolution surface scanner to digitize each unearthed fossil from what's left of the animal's head. This high tech model and the croc's other remains suggest that the carnivore was at least 9 feet tall. Because its forelimbs were so short compared to its skull, the researchers suspect that the carnivore walked on two legs a/la T. rex .

The scientists don't yet have hard evidence -- such as stomach contents or unique bite marks on other animal fossils -- indicating what Carolina Butcher hunted. Based on other known animals from this area at the time, however, the scientists believe likely prey candidates were aetosaurs (armored reptiles) and dicynodonts (large-bodied early relatives of mammals). These animals themselves were formidable.

Carolina Butcher was not the only meat-eater around, either.

"The Triassic was a bit of an ecological Twilight Zone: too few plant eaters and an over abundance of predators meant that the hunters often became the hunted," Zanno said.