Saber-toothed cats, specifically *Smilodon populator*, faced significant challenges leading up to their extinction. New research analyzing fossilized remains has revealed that these formidable predators suffered from severe inbreeding and skeletal abnormalities, impacting their mobility. The study, which examined over 100 specimens from South America, found evidence of widespread genetic defects, including fused vertebrae and deformed limb bones. These issues likely hindered their ability to hunt effectively, contributing to their decline.

Lead researcher Dr. Camila Espinoza noted that the inbreeding was likely a consequence of small, isolated populations, a common issue for species nearing extinction. The genetic bottlenecks meant that harmful mutations, even those that weren't immediately fatal, could persist and become widespread within the population. The skeletal deformities observed were not isolated incidents but rather a common trait among the analyzed fossils, suggesting a systemic problem.

These findings challenge previous assumptions about the cause of saber-toothed cat extinction, which often focused on competition with other predators or changes in prey availability. Instead, the research points to internal biological factors—specifically, the detrimental effects of inbreeding—as a major contributing cause. The combination of reduced genetic diversity and physical impairments likely made *Smilodon populator* increasingly vulnerable in its environment until it ultimately disappeared around 10,000 years ago.