Research overview: sexual dimorphism and its detection in Smilodon

This overview examines whether Smilodon fatalis showed pronounced size differences between males and females, a question with implications for its social system. Because the La Brea sample is large, researchers have searched its skeletal measurements for the bimodal size distribution expected under strong dimorphism, as seen in some social mammals. Results have been mixed and contentious: some analyses find only modest dimorphism, weaker than in many living cats, while others detect subtle patterns in particular elements. The survey reviews the statistical challenges of inferring sex from fossil bones, how dimorphism relates to mating systems and group structure, and why the low apparent dimorphism of Smilodon complicates straightforward analogies with either solitary or pride-living modern felids.