Machairodus (Machairodus giganteus)

Order: Carnivora

Family: Felidae

Machairodus giganteus, perhaps the largest species known within the genus Machairodus, was a large lion-sized saber-toothed cat with elongated upper canines and cheek teeth efficiently adapted for slicing meat. The animal is known mostly from a variety of fragmentary fossils found through Europe and Asia, with the best-preserved skulls coming from China. Once believed to represent two separate species, one existing in Europe and the other in Asia, the fossils were later united by the Swiss paleontologist Gérard de Beaumont to represent a single species. Members of the genus Machairodus are believed to have first appeared in Eurasia some 15 million years ago and may have gone extinct as recently as 2 million years ago.

The various species of Machairodus show an evolution over time toward more extreme specialization as seen in the genus Homotherium. Machairodus giganteus is believed to be one of the more evolved members of the group possessing the traits that distinguish the Machairodus genus from other cats. Such features include more flattened canines, blade-like cheek teeth, a reduced coronoid process of the mandible (the region on the jaw in which the temporalis muscles attached to produce biting power) and an enlarged mastoid process.

In profile the Machairodus giganteus may have been reminiscent of other cat species but would have possessed a distinctly longer and narrower head. Viewed from the front, a longer muzzle and smaller eyes would have been more apparent in the living animal. Coloration and marking are indeterminable, but one can assume that Machairodus giganteus would have possessed some form of facial markings for recognition and communication within their species and possibly some form of spots or stripes to help conceal them while hunting prey. Other distinguishable traits such as a mane or beard may also have been present in the males to act as visual messages to females or to warn off rival males. Males probably fought violently over territory and mating rights. The sheer size of Machairodus giganteus may have been enough to discourage other predators and probably allowed it to reign at the top of the food chain within their habitat.

Social behavior is also indeterminable but may have paralleled that in modern feline species. Machairodus giganteus is associated with faunas typical of an open plain environment and may have had a life-style similar to that of a modern lion. Machairodus giganteus could have hunted in large packs or in small groups, maybe mating pairs. Large packs would have been beneficial in bringing down the large prey but would have meant more mouths to feed requiring more time pursuing prey. The array of prey animals available varied in size from creatures larger than buffalo such as large giraffids to medium-sized fast-running antelope. Cooperative hunting would have been more advantageous in capturing both large and small prey, using more muscle to take down the large prey and possibly using more successful ambush tactics for the small prey.

Males and females were sexually distinguishable from one another in their size, the male being larger than the female. As the name "Machairodus giganteus" implies, examination of skulls and limb bones indicates that the male members of the species sometimes reached very great sizes. This sexual dimorphic trait is a noticeable characteristic of the Machairodus species. Machairodus giganteus may have been a roaring cat and, as in living cat species, would have been noisy during mating. Litters may have consisted of 3 or 4 cubs and would have been cared for and taught to survive by their mother much in the same way as modern lions and tigers do.