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Updated: Jul 19, 2026
06:41
Assessment of Social Interaction Behaviors
Published on: February 25, 2011
Assessing behavior in extinct animals: was Smilodon social?
Sherman McCall1, Virginia Naples, Larry Martin
1Cellular Pathology and Genetics, Armed Forces Institute of Pathology, Washington, D.C., USA. mccall@afip.osd.mil
Brain, Behavior and Evolution
|April 17, 2003
Summary
Smilodon fatalis, a saber-tooth cat, was likely not social. Evidence suggests they could heal injuries independently and their brain size and tar pit presence do not support social behavior.
Area of Science:
- Paleontology
- Paleobiology
- Animal Behavior
Background:
- Fossil evidence of partially healed injuries in Smilodon fatalis from Rancho La Brea.
- Previous interpretations suggested social behavior in Smilodon fatalis due to these injuries.
Purpose of the Study:
- To rebut the assertion that Smilodon fatalis was a social species.
- To present alternative explanations for fossil evidence attributed to social behavior.
Main Methods:
- Analysis of Smilodon fatalis's physiological capabilities for healing.
- Evaluation of dehydration and starvation as limiting factors for injured animals.
- Comparative analysis of Smilodon fatalis abundance with social and non-social species in the La Brea tar pits.
- Assessment of cranial capacity in relation to sociality.
Main Results:
- Smilodon fatalis possessed metabolic reserves enabling rapid healing without feeding.
- Dehydration, rather than starvation, posed a greater threat, necessitating mobility.
- The presence of Smilodon fatalis in tar pits indicates locomotion.
- The relatively small brain size of Smilodon fatalis is inconsistent with complex social structures.
- Abundance of non-social Golden Eagles (Aquila chrysaetus) rivals Smilodon, while highly social wolves (Canis lupus) and coyotes (Canis latrans) are rare.
Conclusions:
- The available evidence does not support the hypothesis of social behavior in Smilodon fatalis.
- Fossil injuries can be explained by individual survival mechanisms and environmental factors, not necessarily social support.
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