Long journeys are often seen as a survival advantage, helping animals reach food and escape harsh conditions. A new review of hoofed mammals suggests that the habit may have carried a hidden cost. According to a report from The Wildlife Society ([1]), hoofed mammals that travel every year have experienced higher extinction rates than those that stay in one area over roughly the past 100,000 years.
A pattern that runs against expectations
Many hoofed mammals, known as ungulates, evolved to cover great distances between seasonal ranges. That ability has become harder to use. Over the past few hundred years, habitat loss and human development have sharply increased the obstacles animals face when they try to move.
The new findings show a different side of that story. Species that depended on annual movement appear to have disappeared more often than their settled relatives, even though migration once helped them thrive. The result challenges the idea that roaming is always an advantage.
Reading the evidence from fossils and living relatives
The research was published in PLOS Biology. Because no one can observe extinct animals directly, the team combined fossil evidence with movement data from modern hoofed species. They used that combination to infer how 51 species that vanished during the last 100,000 years most likely behaved.
The comparison was striking. About 80 percent of the extinct species were migratory, while only about 46 percent of today’s ungulates follow seasonal routes. That gap is the core of the study’s argument, although it rests on reconstructions rather than direct observation.
Key points from the study
- Migratory behavior appears in roughly 80 percent of the 51 extinct species studied.
- Only about 46 percent of living ungulates are migratory.
- Behavior was inferred from fossil records and modern movement data, not observed directly.
- The authors describe migration as a possible driver of speciation, a pattern also seen in birds.
Why movement may now carry more risk
The authors argue that migration can leave a species exposed when its environment changes quickly. A route that worked for thousands of years can become unusable once farmland, roads or settlements block the way. Animals that need several distinct habitats in a single year have more places where that disruption can occur.
The researchers put the concern plainly in a press release. “Migration may bias species toward extinction,” they said, pointing to the danger of depending on long movements in a world increasingly shaped by people. The warning is directed at the broader pattern rather than a prediction for any single herd.
The study also raises a question about how species diversify. The authors suggest that migratory behavior may help drive speciation, the process by which new species form. They note that a similar pattern has been observed in birds, which gives the idea some support beyond a single group of animals.
What the findings do not settle
Fossil-based reconstruction has clear limits. Fifty-one species is a useful sample for a long timescale, but it cannot capture every lineage that disappeared, and inferring behavior from remains always involves uncertainty. The study identifies a strong association between migration and extinction risk, yet the precise mechanisms are not fully explained by the available summary.
Those caveats do not weaken the central message. They point to the next questions researchers will need to answer, such as which migration routes are most vulnerable and how modern land use interacts with long-distance movement. For conservation planners, the practical lesson is that keeping seasonal pathways open may matter as much as protecting the places where animals spend their time.
