Homotherium (Homotherium latidens)

Order: Carnivora

Family: Felidae

Homotherium latidens, perhaps one of the most well known of the saber-toothed cats, belonged to a group of lion-sized saber-toothed cats that lived around 3 million years ago and are believed to have gone extinct about 500,000 years ago. Believed to have evolved from a species of Machairodus cats, the genus Homotherium shows extreme specialization and distinctive skeletal features.

Homotherium latidens and related species were very successful and widely distributed. Although widely known, Homotherium fossils are mostly fragmentary material found throughout Europe and Asia. Specimens have also been found in Africa, where they are referred to as Homotherium ethiopicum and Homotherium hadarensis, and even in North America, where they are referred to as Homotherium serum (serum meaning 'late'). In Europe, An extraordinary skeleton is known from the fossil deposits of Senéze, France. Fossil remains in North America are rare but widely distributed and are usually represented by a few isolated bones and teeth. An exceptional articulated skeleton was found in a Texas cave along with the remains of at least 30 individuals of all ages. The milk teeth of more than 70 young mammoths were found in the same deposit and indicates that the North American Homotherium may have developed a specialized predation.

Homotherium would have had a unique appearance and been distinguishable from other cat species. Their skeletal structure has many peculiar attributes when compared and contrasted with those of living cats and other extinct species as well. In comparison to its ancestor, the Machairodus, Homotherium possessed a shortened lumbar region and elongated radius.The forelimbs were much longer in proportion to their hind limbs. Such proportions are suggestive of a reduced ability to jump and leap. This characteristic is unique to the Homotherium, giving it a sloping back reminiscent of that seen in hyenas. The sloping back is even more apparent in the North American specimens referred to as Homotherium serum. It has been suggested that Homotherium latidens fell into an intermediate position between pantherine cats and hyenas.

Color patterning and markings are impossible to know from fossil evidence alone. Their markings and patterning were probably as varied as their habitats and may have differed according to the individual environments in which they were living and hunting. Those living in colder climate would have had thicker coats to comb at the cold weather and could have been patterned to blend into the snow as seen in snow leopards. Woodland varieties may have possessed some form of stripes or spots to help conceal them when hunting prey, and those living on open plains may have had a more drab appearance allowing them to blend into their grassy domain.

Several different species based on differences in body sizes and the size and curvature of the canines have been proposed. Such species include Homotherium nestianus, Homotherium sainzelli, Homotherium crenatidens, Homotherium nihowanensis, and Homotherium ultimum, all of which may represent individuals of the same species, Homotherium latidens.

The life-style and social habits of Homotherium are a matter of speculation and interpretation. Its morphology is suggestive of something unique among the saber-toothed cats. The cats possessed long powerful limbs that would have allowed them to travel over long distances. Examination of the forelimbs indicates they may have been very capable of chasing down and grappling with large prey. Based on its anatomical similarities to hyenas, Homotherium may have been an active scavenger as well as a predator much in the same way as seen in hyenas.

As all the other saber-toothed cats before and after them, Homotherium eventually succumbed to extinction. Causes of their extinction are unknown and cannot be associated with a single event. It is likely that new and less specialized cat predators may have come on the scene and simply outcompeted with Homotherium in their habitat. A change in fauna may have also resulted in their demise. Homotherium may have evolved and adapted to specific prey animals, as suggested by their distinct morphology. It's possible that a change or reduction in Homotherium cats' usual prey mayhave caused stress upon their populations. The highly specialized form and behavior of Homotherium could have rendered them incapable of adapting to rapidly changing conditions.