The iconic saber-toothed tigers didn’t vanish in a single catastrophic event—they slowly starved to death as their prey disappeared over millions of years.

Research published in the Journal of Evolutionary Biology reveals that the decline of these fearsome predators began long before the end-ice age megafauna extinctions, driven by a gradual reduction in available prey that made their specialized hunting strategy unsustainable.

Saber-toothed cats of the genus Smilodon devouring their prey. A loss of diversity occurred due to fewer herbivores to prey on, which led to extinction

The study challenges the popular notion that saber-toothed cats died out suddenly 11,000 years ago alongside mammoths and giant ground sloths. Instead, it shows a pattern of extinction spanning millions of years, each coinciding with periods when large herbivores became scarce.

A 20-Million-Year Evolutionary Detective Story

Researchers at the State University of Campinas in Brazil analyzed fossil databases, body size estimates, and climate data spanning 20 million years across North America and Eurasia. This comprehensive approach allowed them to trace how predator-prey relationships influenced the rise and fall of these specialized hunters.

João Nascimento, who led the research during his PhD studies, discovered that the extinction pattern began much earlier than previously thought: “Throughout the group’s history, there have been several different species of saber-toothed cats. Our study shows that the extinctions of some of them, throughout the group’s history, generally occurred at times when prey diversity was lower.”

The analysis revealed that saber-toothed cats reached their peak diversity around 8 million years ago, with eight species coexisting. Their numbers remained stable until about 6 million years ago, when diversity began declining and eventually stabilized at five species before their final extinction.

The Price of Specialization

Saber-toothed cats evolved extraordinary elongated canines—sometimes over 7 inches long—that made them supremely effective at killing large prey. However, this specialization became their downfall when climate changes altered the landscape and prey availability.

Key findings from the research include:

• Climate-driven habitat loss: Increasing aridity expanded grasslands while reducing forests, favoring small grazers over large browsers
• Prey switching difficulties: Specialized anatomy prevented adaptation to smaller, more agile prey
• Timing correlation: Most saber-tooth extinctions occurred when prey richness reached its lowest point for each species
• Geographic patterns: North American extinctions showed strongest correlation with declining horse family (Equidae) diversity

The research demonstrates how evolutionary specialization can become an evolutionary trap when environmental conditions change rapidly.

A Tale of Two Evolutionary Pressures

In a companion study published in Evolution, the same research team examined the flip side of this predator-prey relationship by studying antilocaprids—relatives of modern pronghorn antelope. These herbivores once dominated North American landscapes with dozens of species but now survive as a single species.

The antilocaprid decline reveals how increasing predator diversity can drive prey extinctions. The emergence of new felid species, including the American cheetah adapted for high-speed pursuit, placed unprecedented pressure on these herbivores. This predation pressure may explain why modern pronghorns evolved to become among the fastest land animals in North America.

Mathias Pires, who supervised the research, emphasizes the broader significance: “The great contribution of this set of studies is precisely to present the idea that the interaction between predators and prey can have an effect on large evolutionary patterns. This had been debated for decades, but there was no really robust set of results to support this hypothesis.”

Lessons for Modern Conservation

The research provides crucial insights for understanding current extinction patterns. By analyzing how predator-prey relationships shaped evolutionary history, scientists can better predict how modern ecosystems might respond to ongoing environmental changes.

The study was made possible by extensive fossil databases from North America and Eurasia, which include detailed information about body size, diet, and temporal distribution. These freely available online resources allowed researchers to estimate when species emerged and went extinct, as well as which animals coexisted and interacted during the same periods.

The findings reveal a cyclical pattern: environmental changes reduce prey availability, which increases predator extinction risk, which in turn affects future prey evolution. This dynamic continues to play out today as human activities drive habitat loss and species extinctions.

Pires concludes with a sobering warning: “We’re showing how an increase in predators can reduce the availability of prey, which in turn reduces the abundance of predators, and how this can manifest on an evolutionary scale. It’s a warning about how we may be altering the future with the extinctions we’re causing now.”

The research demonstrates that even apex predators aren’t immune to the consequences of environmental change. The mighty saber-toothed cats, despite their fearsome reputation and evolutionary success over millions of years, ultimately couldn’t escape the fundamental ecological truth that predators depend entirely on their prey’s survival.