Scientists are not literally resurrecting Smilodon, the iconic saber-toothed cat that vanished roughly 10,000 years ago, but a handful of research groups are seriously exploring whether its genetic blueprint could be used to engineer a living approximation. The effort sits at the intersection of ancient DNA recovery, gene-editing technology, and a growing school of conservation thought called trophic rewilding, which argues that restoring lost apex predators can repair ecosystems that have been unraveling since the Pleistocene. Whether the saber-tooth is actually a realistic candidate for this treatment is a different question from whether the science is interesting, and the answer to the second is a resounding yes.
What Scientists Have Actually Recovered So Far
The genetic story of Smilodon starts with fossils pulled from asphalt. Back in 1992, researchers developed a method to extract preserved cellular DNA from 14,000-year-old bones of Smilodon fatalis found at Rancho La Brea in Los Angeles. They managed to clone and sequence two distinct gene segments, one mitochondrial and one nuclear, from three individual specimens.1PubMed. Molecular phylogenetic inference from saber-toothed cat fossils of Rancho La Brea That was a proof of concept, but it gave researchers only tiny fragments of a vast genome.
More recently, a team used an African lion genome as a reference and mapped a draft nuclear genome of a single Smilodon populator individual, dated to about 13,182 years ago, to roughly 0.7x average genome-wide coverage. They combined whole-genome capture, using baits made from modern lion DNA, with exome capture based on annotated lion genes.2PubMed Central. A genomic exploration of the early evolution of extant cats and their sabre-toothed relatives The result is the oldest palaeogenome ever recovered from South America, a region where heat and humidity usually destroy ancient DNA. Separately, partial mitochondrial genomes have been assembled from one Smilodon populator sample and three Homotherium samples, including the only known Late Pleistocene Homotherium specimen from Eurasia.3Current Biology. Evolutionary History of Saber-Toothed Cats Based on Ancient Mitogenomics
None of this amounts to a complete genome. A 0.7x coverage draft is full of gaps, and you need far more than a rough sketch to reconstruct an organism. But it is enough to start identifying which genes were unique to saber-toothed cats, which ones they shared with modern big cats, and, critically, how far apart those lineages really are.
The Deep Divergence Problem
Here is where the saber-tooth project gets genuinely hard. Smilodon and modern cats are not close cousins. The genomic data put the divergence between Smilodon and Homotherium at about 20.65 million years ago, and the split between the saber-toothed lineage (Machairodontinae) and the lineage that includes all living cats (Felinae) is at least as deep.2PubMed Central. A genomic exploration of the early evolution of extant cats and their sabre-toothed relatives The analysis also confirmed no detectable gene flow between Smilodon and contemporary cat species, meaning these lineages did not interbreed during the millions of years they coexisted.
To put that 20-million-year gap in perspective, the divergence between humans and their closest great ape relatives is only about 6 to 7 million years. The genetic distance between a lion and Smilodon is roughly three times larger than the distance between you and a chimpanzee. That matters because the leading de-extinction strategy involves editing the genome of a closely related living species to make it resemble the extinct one. The closer the relative, the fewer edits are needed. For the woolly mammoth, whose closest living relative is the Asian elephant (diverged about 5 to 6 million years ago), the task is already considered enormous. For Smilodon, the task is staggeringly larger.
How De-extinction Is Supposed to Work
The general approach for de-extinction involves taking the genome of an extant species and modifying it according to available genetic information from the extinct species. You need the extinct animal’s genetic material, one or more appropriate living relatives as both a genetic template and a surrogate for reproduction, and the ability to edit cells and bring them to term. The process typically relies on somatic cell genome editing.4PubMed Central. Emerging trends in genome editing of wild animals
For Smilodon, the theoretical plan would involve taking cells from a modern big cat, probably a lion given that lions were used as the reference genome, and using CRISPR or similar tools to swap in key Smilodon genes one by one. The edited cells would then need to be turned into embryos and implanted in a surrogate mother. We know from existing work that cats can be cloned: researchers have produced second-generation cloned cats using somatic cell nuclear transfer, showing that cloned cats can themselves serve as donor animals for further cloning.5PubMed Central. Production of second-generation cloned cats by somatic cell nuclear transfer But cloning a domestic cat and engineering a functional approximation of a 200-kilogram Pleistocene predator are problems of completely different scales.
The cloning efficiency in those cat studies was low, with about 20 to 26 percent of surrogate mothers delivering any offspring at all, and many kittens were stillborn or died shortly after birth.5PubMed Central. Production of second-generation cloned cats by somatic cell nuclear transfer Scaling that up to a wild felid whose genome has been substantially edited adds layers of difficulty that nobody has solved yet for any species, let alone one separated from its surrogate by 20 million years of evolution.
Why Bother in the First Place
The motivation is not nostalgia. It is rooted in a conservation framework called trophic rewilding, which uses species introductions to restore top-down ecological interactions. The logic goes like this: large predators regulate herbivore populations, which in turn shapes vegetation, which in turn influences everything from soil carbon to water cycles. When those predators vanish, the whole cascade breaks down, a process researchers call trophic downgrading. Trophic rewilding tries to reverse that by reintroducing predators, or suitable ecological stand-ins, to ecosystems that lost them.6PubMed Central. Science for a wilder Anthropocene: Synthesis and future directions for trophic rewilding research
There is evidence that saber-toothed cats filled exactly this kind of keystone role. Fossil sites show that homotherine sabertooths hunted and consumed animals ranging from peccaries to juvenile mammoths, making them apex predators whose hunting and feeding behaviors influenced prey demographics and the resources available to other scavengers and predators in the Pleistocene food web.7Scientific Reports. Sabertooth carcass consumption behavior and the dynamics of Pleistocene large carnivoran guilds The disappearance of these animals left ecological vacancies that no surviving predator fully fills.
The rewilding argument does not require resurrecting an exact genetic replica of Smilodon. What matters is functional equivalence: an animal that occupies the same ecological niche, hunts similar prey, and exerts similar pressure on the landscape. A genetically edited big cat that behaved like a large ambush predator and occupied the same trophic position could, in theory, deliver the same ecological benefits. Whether that is a realistic goal or a thought experiment dressed up as science is the real debate.
What Actually Killed Smilodon
Understanding why an animal went extinct matters enormously if you are thinking about bringing it back. If the original cause of extinction is still present, reintroduction is pointless. The question of what killed saber-toothed cats has been studied using dental microwear texture analysis on La Brea fossils, which tracks how much an animal was crunching bone and other tough tissues (a sign of desperation and food scarcity).
The findings are interesting: comparing older deposits (around 30,000 to 35,000 years ago) to younger ones (around 11,500 years ago), researchers found little evidence that declining prey resources drove Smilodon to extinction. Carcass utilization did not increase over time, and if anything it slightly decreased in the American lion (Panthera atrox), another large predator that went extinct at the same time. The data are not consistent with the idea that human hunters caused extinction by competing for prey or reducing prey populations at La Brea.8PLOS ONE. Implications of Diet for the Extinction of Saber-Toothed Cats and American Lions
This complicates the standard narrative that human overhunting of megafauna indirectly doomed the big predators. The cause of Smilodon’s extinction was likely a combination of factors, including rapid climate shifts at the end of the Pleistocene, habitat changes, and the disappearance of the broader megafaunal community it depended on. For de-extinction advocates, this is somewhat encouraging: it means the threat was not a permanent environmental condition but a cascade of events that has since stabilized. For skeptics, it is a reminder that the Pleistocene ecosystems saber-tooths evolved in no longer exist.
An Animal Built Differently Than Anything Alive
One underappreciated challenge is that Smilodon was not just a big cat with long teeth. Its entire anatomy was structured around a hunting strategy unlike anything in the modern cat family. Studies reconstructing its bite mechanics found that Smilodon fatalis produced bite forces of roughly 1,284 newtons at the canine and about 4,671 newtons at the carnassial (the slicing tooth further back in the jaw).9PubMed Central. Myological and osteological approaches to gape and bite force reconstruction in Smilodon fatalis Those numbers are comparable not to lions or tigers but to jaguars, which are much smaller animals. The canine bite force was actually slightly lower than a jaguar’s, while the carnassial force was higher.
This means Smilodon did not kill the way modern big cats do. Lions suffocate their prey with a sustained throat clamp. Smilodon appears to have killed with slashing canine bites powered partly by its massive neck and forelimb muscles rather than jaw muscles alone. Its skull, jaw joints, and post-cranial skeleton all coordinated in ways that have no parallel among living cats. Recreating those saber teeth through gene editing would be meaningless without also recreating the skull geometry, the musculature, the neurological wiring for the hunting behavior, and the skeletal proportions that made the whole system work. That is not a handful of gene edits. It is an entirely different body plan.
The Population Problem
Even if you could create a single living Smilodon proxy, you would need a population of them for the project to have any conservation meaning. And this is where population genetics creates a nearly intractable bottleneck. When species pass through severe population crashes, they lose genetic diversity and accumulate harmful mutations, a cycle that reduces fitness and can trap a population in an extinction spiral even after its numbers recover.10Journal of Heredity. De-extinction technology and its application to conservation
A de-extincted species starts from the most extreme bottleneck possible: a population of essentially zero, rebuilt from a single genome template. Conservation geneticists have laid out the challenge directly. To give translocated populations of de-extincted animals any real chance of surviving beyond the first few generations in the wild, you would need to create sufficiently large, genetically diverse populations that can adapt to changing environments.11Functional Ecology. Maximising evolutionary potential in functional proxies for extinct species: a conservation genetic perspective on de‐extinction With only one sequenced Smilodon genome and no way to sample genetic variation across the species’ former range, building that diversity from scratch would require genetic engineering on a scale that does not yet exist.
The genetic bottlenecks stack up in sequence: first the limited ancient DNA that survived, then the narrow template used for editing, then the small founding population in captivity, and finally the translocation to the wild. Each stage strips away adaptive potential. For a species that needs to hunt, avoid disease, thermoregulate, and navigate complex social behaviors, the genetic poverty of a de-extincted population is not a minor obstacle. It is arguably the single biggest biological barrier to any de-extinction project reaching ecological relevance.
Where Would You Put It
Habitat suitability is a challenge for any large predator reintroduction, even with species that still exist. Research on reintroducing wolves to parts of western Colorado found that while roughly 56 percent of the study area contained ecologically suitable habitat, much of that area also overlapped with high human-conflict risk.12ScienceDirect / Elsevier. Defining ecological and socially suitable habitat for the reintroduction of an apex predator For a predator like Smilodon, which probably weighed two to three times as much as a wolf and hunted much larger prey, the habitat requirements would be even more demanding. You would need vast expanses of land with large ungulate populations, minimal livestock presence, and communities willing to coexist with an apex predator of a kind no living person has ever seen.
Smilodon’s original range covered most of the Americas, from the tar pits of Los Angeles to the grasslands of Argentina. Almost none of that range still looks the way it did during the Pleistocene. The megafaunal prey base, including ground sloths, horses (before their North American extinction), camels, and juvenile proboscideans, is gone. A saber-tooth proxy would need to hunt modern prey species like deer, elk, or bison, using a killing strategy that evolved for a different set of animals entirely. Whether those hunting behaviors could even develop in an animal raised in captivity, without cultural transmission from experienced adults, is an open question that applies to all large carnivore de-extinction proposals.
Legal Gray Zones
If a saber-tooth proxy were created, what would it legally be? Existing conservation law was not designed for de-extincted organisms, and legal scholars have flagged two core problems. First, the taxonomic definitions and species-classification methods used by conservation frameworks would be challenged by an animal that does not fit neatly into any recognized species. Second, it is unclear whether laws like the Endangered Species Act in the United States or equivalent frameworks in the European Union would extend protections to a de-extincted organism, or whether it would fall into a regulatory gap as neither a protected wild species nor an ordinary domestic animal.13Journal of Environmental Law. De-Extinction, Regulation and Nature Conservation
This is not a hypothetical worry for the distant future. The woolly mammoth de-extinction project led by Colossal Biosciences has already raised similar questions, and no jurisdiction has resolved them. A saber-tooth proxy could end up classified as a genetically modified organism (subject to biosafety regulation), an exotic pet (subject to state-level wildlife laws), or a novel wild animal (potentially subject to conservation protections). The legal ambiguity could delay or block any release into the wild, even if the biology were somehow solved. It could also create perverse incentives: if a de-extincted predator has no legal protection, there would be nothing stopping someone from killing it.
What Saber-Tooth Research Actually Contributes Right Now
The honest assessment is that a living, breathing Smilodon proxy is not arriving anytime soon, and most of the researchers involved in ancient DNA and paleo-genomics know this. The more immediate scientific payoff is in understanding felid evolution, developing better ancient DNA recovery techniques, and refining gene-editing methods that could be applied to conservation problems that are solvable today. Sequencing Smilodon’s genome has already revealed that sabertooth lineages diverged far earlier than previously thought, forcing revisions to the cat family tree and showing that the fossil genus Pseudaelurus, long considered ancestral to both saber-tooths and modern cats, includes species younger than the lineages they supposedly gave rise to.2PubMed Central. A genomic exploration of the early evolution of extant cats and their sabre-toothed relatives
Technologies developed for de-extinction could also help living endangered cats. Cloning, gene editing, and reproductive technologies pioneered in the context of de-extinction are directly applicable to genetic rescue of species on the brink, like the cheetah, which has infamously low genetic diversity, or the Iberian lynx, which passed through a population bottleneck of fewer than 100 individuals. De-extinction research functions partly as a technology incubator for mainstream conservation, even if the flagship species it promotes are unlikely to walk the Earth again. The saber-tooth draws public attention and research funding; the tools built along the way may end up saving species that still have a chance.