Ancient migration between wild horse populations in America and Asia show how ecosystems adapt to survive cataclysmic change — strategies that modern forms of conservation may unintentionally hinder.
That’s the argument of a new study in Science published on Thursday as part of an initiative that blends Western and Indigenous traditions of science in an effort to find new solutions for a natural world in dramatic flux.
Their main conclusion: When the going gets tough, tough ecosystems get going — carried along by keystone species like horses, whose willingness to explore new terrain and interbreed with other horse populations has spread their DNA from Alaska to Western Europe.
This kind of motion is integral to the survival of complex life on Earth, the study argues — and it’s something that conservation needs to better emphasize.
“Today, we live in a world where the boundaries and obstacles created by mankind do not serve the majority of life,” wrote Jane Stelkia, an Okanagan elder and co-author of the paper.
“It is time that humans help life find the openings and points to cross and move safely,” Stelkia added.
Thursday’s paper is the second offering from a broader collaboration that first bore fruit in a groundbreaking 2023 paper, also in Science, that found that Native Americans had kept and cared for horses for generations — at least — earlier than historians had once believed.
The findings released this week relied on the work of dozens of scientists and traditional elders from Siberia, the Great Plains and Northwestern Canada to assemble the largest ever genetic database of Ice Age horse fossils.
That expanded by 30 times the number of sequenced Ice Age horse genomes known to science from two to more than 60.
The genetic information in those bones revealed a lost “Arctic highway” that once linked the grasslands of North America and Eurasia, lead author Ludovic Orlando of the Center for Anthropobiology and Genomics of Toulouse told The Hill.
Genes from Alaskan horses in specimens found in Spain “cannot just emerge by chance in both continents,” Orlando said. “They must have been shared by horses migrating along and actually having kids with local [horse] populations — not as a one-off event, but a number of times.”
This ancient highway repeatedly opened and closed as the ice sheets expanded and retreated — and the land bridge between Asia and the Americas was exposed and submerged — between 50,000 and 13,000 years ago.
In that period, Orlando noted, there were just two separate lineages of humans — our line and the Neanderthals.
But at that same time, the team’s research revealed dozens of lineages of horses, some so different that scientists had once thought of them as different species — but which recent genetic evidence shows would have been similar enough to interbreed, and did so.
That ancient migration and hybridization helped horses to survive across an enormous range into the modern day, the scientists found — the kind of movement that modern political borders, and 20th-century notions of conservation, increasingly block with fences.
“The Western frame is: You buy a piece of property, if you’re lucky, you stay there — and then if the tornado comes, well, it sure sucks to be you,” Running Horse said. “In the past life moved, right? You’re not falling in the ocean, you know?” she said. You just know the threat is coming, and you move.”
The paper is part of a broad reevaluation of the relationship between Western and Indigenous modes of science — with science defined as systems that use observation, experimentation and deductive reasoning and peer review to develop working theories of how the universe operates.
The difference between these perspectives presents both significant challenges and opportunities, Orlando said: The Lakota “have a radically different way of doing science” that can often make cross-cultural discussions “almost impossible.”
But after years of collaboration, Orlando said, he has come to realize that entwined in those systems are powerful perspectives that Western science is only now coming to appreciate: “a number of concepts I might never come to in my life, that are now available to me, or to anybody, or a toolbox that is unlocked — a radically different way of doing science.”
These differences creep in at the very root. Western science, Orlando noted, is built on order and separation. Western scientists focus on objectivity, and separation from their subject, a tendency that extends to their ordering systems.
The organizing principle of classical Western biology, for example, is the individual species, or — heading up the chain of Linnaean classification — the genus, order or kingdom. (Even the idea of an atomic unit, taken from chemistry, reflects this unconscious bias.)
That idea, both Orlando and Running Horse said, carries over into Western ecology in the idea of habitats as tied to specific geographic ranges — seen in the fixed boundaries of national parks, which tend to be islands surrounded by vast swaths of private land — and concerns about saving individual species.
In this context, for example, it makes sense to worry about polar bear-grizzly hybrids outcompeting polar bears; to bring back extinct species like the dire wolf; or to shoot “invasive” elk.
But this perspective, Running Horse said, is very different from the Lakota approach, in which the core unit of organization is not the individual but the ecosystem.
In that perspective, rather than focusing on individuals, biology becomes about a network of relationships from the smallest scale (the microbiome within the gut of an individual animal) up to the broadest web of organisms a given species interacts with.
In practical terms, Running Horse said, what that means is that to Lakota scientists, the hybridization of polar and grizzly bears is an adaptive strategy — the seal-eating cousins coming south to rejoin their salmon-eating brethren.
Reintroducing dire wolves becomes next to impossible, because the whole network of dire wolf relationships — from the now-extinct microbes in their guts to the species they preyed on and the carrion-eaters that ate their bodies — are now gone.
And invasive species are simply doing what life always does to adapt to changing conditions: moving, and helping ecosystems move along with them — an idea that echoes a 2024 paper in Science that found large introduced herbivores like feral pigs and donkeys might actually be beneficial to landscapes.
This focus on relationships, Running Horse said, helps us see that those ancient migrating family groups of horses also helped “move other forms of life around.”
As the horses moved, for example, they ate seeds, many of which pass through their guts to land, in piles of fertilizer on the other side — sprouting new plants. Specialized insects lay their eggs in the drying horse manure, which are preyed on by birds, which spread fruit seeds in their own droppings. Predators like wolves followed the herds as well, along with their own companion species — from microbes to crows.
The great horse highway, sporadically broken by ice sheets and rising seas, ultimately collapsed 12,000 years ago as the climate warmed. In the northwest of what became America, bogs and boreal forests replaced the dry plains and steppe, fed upon and spread by large grazers like wapiti, moose and elk — who lived on, and helped create, the forests that now define the region.
Today, things are shifting again. As the climate heats up, wet forests across the Americas are increasingly riven by fires, which are changing the composition of trees — and which may be bringing back the grasslands from Alberta to the Amazon, creating new opportunities for grazers like horses and buffalo.
For a world facing the upheaval of climate change, Running Horse said, the practical response is to facilitate adaptive movement across a changing landscape: “the creation of corridors that would allow life to move — together — as needed.”
But she made a more philosophical point, too. Faced with radical change, “it is tempting to look back to the past and say that we need to ‘go back,’” she said.
But in her tradition, “we understand that the true gift we can bring to life is to deal with what is, and bring to it what is needed.”
In that paradigm, Running Horse said, research into horse migration offered a model for navigating a more chaotic future — a scenario she compared to the experience of getting lost on horseback in the dark, in the middle of a thunderstorm.
In that scenario, she said, the smart rider stops struggling and takes refuge in trust. “You put your arms around the neck of the horse, and the horse goes right where you need to be.”
