The mysterious primate appeared in North America 30 million years ago, long after the continent’s native primates went extinct and even before the next major primate influx: humans. This lemur-like species, called Ekgmowechashala, has long puzzled paleontologists. Was it the last survivor of North American primates, or did it migrate from somewhere? So how did it manage to survive in conditions that wiped out the continent’s other primates 4 million years ago?

There’s still a lot we don’t know, but according to a new study, we finally have new clues, including possible evidence of Ekgmowechashala’s origins. Researchers have known about Ekgmowechashala since the 1960s, explains lead author Kathleen Rust, a paleontologist at the University of Kansas. However, our knowledge is based on very few fossil remains, mostly teeth and jaws. Rust notes that these few fossils are “very different,” causing both excitement and disappointment among researchers.

“Due to its unique morphology and representation only in dental remains, its place in the mammalian evolutionary tree has been a subject of debate and debate,” says Rust.

He adds that experts now generally agree that Ekgmovechashala was a primate, but many questions remain. The timing and manner of its emergence in North America, for example, are “quite unusual.”

“It suddenly appears in the fossil record of the Great Plains, 4 million years after all other North American primates went extinct,” says Rast.

The first appearance of primates in the North American fossil record dates back to the beginning of the Eocene epoch, about 56 million years ago, roughly the same time as their appearance in Asia and Europe.

Paleontologist Chris Byrd from the University of Kansas explains that they lived in North America for more than 20 million years. But that changed about 34 million years ago, he says, as the Eocene gave way to the cooler, drier climate of the Oligocene, leading to the extinction of North America’s native primates.

“After a few million years, Ekgmowechashala seems like a stray in a Western movie, but it becomes a flashpoint in a long evolutionary trajectory,” says Bird.

In search of context, researchers reconstructed the Ekgmowechashala family tree, aided by the discovery of an older “sister taxon” from China.

A Chinese fossil named Palaeohodites (meaning ancient wanderer) sheds light on how Ekgmowechashala reached North America, according to a new study. Researchers say he was an immigrant, not a renegade, from the continent’s once-thriving primate community.

“Our analysis refutes the idea that Ekgmowechashala was a primate that lived or survived in North America,” says Rust. “Instead, it was a migratory species that evolved in Asia and migrated to North America, most likely via Beringia, during a surprisingly cool period.”

Byrd was among the scientists who found Ekgmowechashala-like fossils while working in the Nadu Formation in Guangxi, China, in the 1990s. Because these ancient primates were so unique, their importance was immediately obvious, he says.

“When we were working there, we had no idea that we would find an animal closely related to this strange primate from North America, but the moment I held the jaw in my hand and saw it I literally thought, ‘Wow,’ there it is.” says Byrd.

According to him, the palaeocodite fossil resembles the characteristic upper molar of Ecgmovechahal, but further analysis was required. This is where Rust came into being.

“We collected a significant amount of morphological data to build an evolutionary tree using phylogenetic reconstruction software and algorithm,” says Rust.

The resulting family tree “suggests a close evolutionary relationship between the North American Ekgmowechashala and paleowalkers in China,” he adds. “The results of our analysis clearly support this hypothesis.”

Ekgmowechashala likely migrated from Asia to North America via the Bering Land Bridge, one of the routes humans may have used to reach the Americas, about 25 million years after Ekgmowechashala went extinct.

Although Ekgmowechashala and earlier North American primates faced natural climate change, their history may still provide valuable insight into humanity’s modern struggle against self-induced climate change, Rust says.

“It is extremely important to understand how past biota responded to such changes,” he says, noting that “organisms often either adapted by retreating to more hospitable areas with available resources or faced extinction.”

About 34 million years ago, the climate of North America changed too quickly for native primates to adapt. “This highlights the importance of available resources for our non-human primate relatives in times of extreme climate change,” says Rast.

“Understanding this history is not only humbling, it also helps us appreciate the depth and complexity of the dynamic planet we live on,” he adds. “It enables us to understand the complex workings of nature, the power of evolution at the origin of life, and the impact of environmental factors.”