Therefore, it would tend to hold more credibility. Social theories based on bone breakage were based on theory alone. When one considers the merits of these two conflicting theories, one has to examine the behaviors and condition of modern animals, especially when making such general statements.
If one considers what happens to modern animals when they are hurt, the non-social theory would have more support. Dehydration would be the most critical factor in death after an injury. However, one flaw in this theory is that they gave no comparison of evidence to support their supposition that the animals could live on their body mass while healing. There is simply not enough known about the metabolism of the smilodon to make such as suggestion. Overall, the theories of McCall, Naples, and Martin hold more credibility than the social theories, save for the one exception.
Genetics and DNA
Several researchers were able to extract and clone DNA from the fossil bones of three different smilodons from the tar pits. They found that the smilodon is related to 15 known modern species including 9 species of cat and 6 non-feline species. This confirmed the theories that smilodon was distinct from the saber toothed cat that appeared during the Miocene period (Janczewsi and associates). The most important result that came from this study was that we now know it is possible to clone DNA and obtain valuable information.
Examining the fine structures on the large maxillary tells us that the tooth had the capability of providing sensory information to the brain (Riviere and Wheeler). Martin, Bariarz, Naples, and Hearst discussed the emergence of a new species found in Florida that had a different tooth shape than other saber-toothed cats. The canines of smilodons were different. Many of the cats in North America are known as the longer dirk-tooth. That is two finely serrated canines. These cats had short legs that were built for power rather than speed. Other cats had shorter scimitar-shaped canines and longer legs for speed. The new species found in Florida has the scimitar-tooth as well as the short limbs of the dirk-tooth cat (Slaughter, 486-492).
As far as body mass is concerned, three different species were examined (Christiansen and Harris). Based on variables from the skeletons of modern cats it was found that'd. gracilis is more comparable to the size of a modern jaguar. S fatalis was found to be somewhere close to the frame of a Siberian tiger. S. populator was larger and heavier than any living cat. Some exceptionally large specimens of S. populator have been recovered. According to the authors previous estimates were low due to a lack of data.
How the Smilodon Attacked
Rosie and Winters consulted with personnel from Rancho La Brea and the Idaho Museum of Natural History regarding many aspects of the smilodon. When one examines the plant matter found on herbivores it paints a picture of what smilodon's world would have been like. The area was a plain with patches of sagebrush, buckwheat, oak and pine. According to the authors, this would have made an excellent hiding place for the smilodon to stalk its prey.
When stalking its prey, the smilodon often injured itself and pulled soft tissues. The scars of these tissues bear the scars of these injuries. According to Rosie and Winters, the most common position for the body of a smilodon to be in when it attacked was feet forward in a lunge. This would suggest that smilodon would spring onto its prey. This theory was derived from data obtained by counting the number and location of injuries in the fossil record. It might be noted that when one compared the injuries of smilodon to canine species, there were fewer injuries from being kicked in the head. This would indicate that canine species attacked by lunging at the throat or hind quarters, whereas the smilodon landed on top of the animal's back and tried to bowl it over.
According to Rose and Winter, the smilodon's tooth was suited more for ripping a belly than sinking deep into the back. In this article William Akersten, former Rancho La Brea curator, this is similar to the manner in which a komodo dragon attacks. He explains that the saber-teeth are more suited for a forward and backward motion. Animals that attacked by biting the neck would need to be able to go side to side. There are surprisingly few broken saber teeth found. This injury was apparently rare. If the smilodon would have attacked and tried to bite the neck, one would expect to see many more broken teeth as they hit the harder bones of the bigger animal.
Ayonge (1059-1067) examined the molars and wear patterns and compared them to wear patterns on modern animals such as canids and other felids. They found that the wear patterns of S. fatalis were not consistent with the canine teeth of six large carnivores including leopard, panther, cheetah, African lion, spotted hyaena, Crocuta; African wild dog, Lycaon pictus; and Canis lupus. They concluded from this evidence that the diet and killing pattern differed significantly from those of modern animals. They too support theory that smilodon did not come into contact with bone while killing or feeding.
Prevosti and Vizcaino, calculated the biomass of herbivores in South America and found an imbalance that was not present in North America. They found that in South America herbivores far outnumbered large predators. There was a significant lack of large predators in the areas. Smilodon populator was one of the key predators in the area. Populator was one of few predators that would be able to hunt larger herbivores. This study inferred that body mass was an important factor in the number and types of species present in an area.
Robert Feranec found that large carnivores tended to have a preference for their prey according to the diet of the herbivore. Feranec found that one could predict the animal's preferred diet by examining stable carbon and oxygen isotopes on the enamel of the sabre-tooth. He found that some preferred predominantly C3 plants, while others preferred only C4 plants. Feranec found that it took S. Fatalis approximately 18 months to reach full maturity. By comparing these growth rates to modern tigers and lions Feranec was able to extrapolate that'd. fatalis preferred the diet consisted of primarily herbivores that ate C3 plants.
As one can see, there are many different ways to interpret the evidence found at sites such and the California tar pits. Early works were largely theoretically based, particularly those regarding social behavior. However, technological advances have made rapid advances in the data that is being collected from these species. We can learn much from the animals that were hurt and the clues about their fate.
One must remember that human beings were around as the saber-tooth tiger was beginning to die out. Humans painted the large cat on cave walls. One of the approaches that was not found in the literature was an examination of the social habits that were painted on cave walls. Did ancient hominids paint the smilodon in social groups or did they paint them as single hunters? It would be interesting to see if the pictures from early many match the new data that is being put forth by the academic community on the tar pits.
There is even evidence that the smilodon and other large carnivores may have been at least partially responsible for the ability to modern man to move into Europe. Recent findings in Spain, Italy, Georgia and China indicate that human beings arrived in Eurasia much earlier than was first suspected (Basel). According to this author, an examination oldowan tools, indicates that early humans may have feasted on the scraps left by large carnivores such as the smilodon. Humans may owe their ability to move onto the European continent to the scraps of carnivores.
There are many different ways to approach the problems and mysteries associated with the smilodon. However, there are certain patterns beginning to emerge. For instance, we now have to consider the theory that smilodon was hunting alone in the tar pits. This was not even considered to be a possibility in the past. New research is beginning to change our stereotypical view of the smilodon and their habits.
The only thing that can be said for certain is that these large-toothed predatory creatures played a major role in the shaping of the Pleistocene landscape. They controlled the herbivore population so that they would not overrun the habitat. The smilodon plays many of the same roles in the environment that modern predators play. The smilodon was an important predator and new methods for studying them will continue to change our view of them in the near and distant future.
Anyonge, W. Microwear on Canines and Killing Behavior in Large Carnivores: Saber
Function in Smilodon fatalis. Journal of Mammalogy, (Nov., 1996), Vol. 77, No. 4 pp. 1059-1067.