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201619Mar14:38

Saber-​toothed cats hunted on the South Amer­i­can plains

Infor­ma­tion
pub­lished 19 March 2016 | mod­i­fied 19 March 2016
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Saber-toothed cat (Smilodon populator)Uni­ver­sity of Tübin­gen researchers refute the­ory that saber-​toothed cats were for­est dwellers.

Like the lion which today lives in the African savan­nah, the saber-​toothed cat (Smilodon pop­u­la­tor), inhab­ited the open, dry coun­try found in South Amer­ica dur­ing the ice age, accord­ing to Pro­fes­sor Hervé Bocherens of the Senck­en­berg Cen­ter for Human Evo­lu­tion and Palaeoen­vi­ron­ment at the Uni­ver­sity of Tübin­gen. The results of his lat­est study have been pub­lished online on 24 Feb­ru­ary in the jour­nal Palaeo­geog­ra­phy, Palaeo­cli­ma­tol­ogy, Palaeoe­col­ogy. To find out more about the eat­ing habits of what was then South America’s biggest cat, Bocherens and his team exam­ined the bones of saber-​toothed cats which lived in Argentina’s Pam­pas region in the period 25,00010,000 B.C.

It may be that these preda­tors [saber-​toothed cats], too, hunted together in groups.
Hervé Bocherens, lead author, Senck­en­berg Research Cen­tre for Human Evo­lu­tion and Pale­oen­vi­ron­ment, Uni­ver­sity of Tübin­gen, Ger­many »

“Up to now, palaeon­tol­o­gists assumed that a preda­tor weigh­ing up to 400 kilo­grams and with bone struc­ture sim­i­lar to that of a forest-​dwelling cat would have hunted in wood­lands,” says Hervé Bocherens. It was thought that would make it eas­ier for the ani­mals – with their canines up to 30 cen­time­tres long – to find hid­ing places from which to attack their prey. But Bocherens’ study points to a dif­fer­ent con­clu­sion. He com­pared col­la­gen sam­ples from the bones of var­i­ous ice age preda­tors – includ­ing the saber-​toothed cat, the jaguar (Pan­thera onca), and a species of wild dog (Pro­to­cyon) – with those of their likely prey. The car­bon and nitro­gen iso­topes he found there enabled him to draw con­clu­sions about the kind of envi­ron­ment the ani­mals lived in.

Saber-toothed cat prey speciesThe prey (green) of ice age preda­tors (red).
Graphic: Bocherens/​Uni­ver­sity of Tübin­gen.
The saber-​toothed cats didn’t eat ani­mals which were native to thickly wooded coun­try. Their main prey species seems to have been a camel-​like, steppe-​dwelling ungu­late known to sci­en­tists as Macrauche­nia, and two species of giant sloth (Megath­erium and Lestodon) — who, unlike their sur­viv­ing rel­a­tives, lived on the ground and could grow to sev­eral tonnes in weight. There could be a fur­ther par­al­lel with today’s African lions; the bones of sev­eral indi­vid­ual saber-​toothed cats were found together and con­tained sim­i­lar iso­topes, Bocherens says – “It may be that these preda­tors, too, hunted together in groups.”

The saber-​toothed cat (Smilodon) evolved in North Amer­ica and spread to South Amer­ica with the for­ma­tion of a sta­ble land bridge between the two con­ti­nents some three mil­lion years ago. It appears that the saber-​toothed cats’ fiercest com­peti­tors were not other big cats. The study indi­cates that the jaguar pre­ferred smaller prey, such as rodents and species of horse. But the ice age dog (Pro­to­cyon) seems to have shared the saber-​tooths’ culi­nary taste.

Many types of megafauna died out at the end of the ice age, includ­ing the saber-​toothed cat. Researchers debate the pos­si­ble influ­ence of cli­mate change and human activ­ity on the extinc­tions. The Tübin­gen researchers believe that a more humid cli­mate could have led to increased foresta­tion of the steppe — reduc­ing the saber-​toothed cats’ hunt­ing grounds and ulti­mately caus­ing them to die out.

(Source: Uni­ver­sität Tübin­gen press release, 17.03.2016)


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Tiger map” (CC BY 2.5) by Sander­son et al., 2006.

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