On the side of a remote road in southern Brazil, in 2021, someone hit an animal with their car. A sad story, but not an uncommon one—except in this case, the creature survived. And no one knew what it was.
“What a strange hybrid beast!” tweeted Professor Roland Kays, director of the Biodiversity Lab at the North Carolina Museum of Natural Sciences, two years later. By that time, a scientific article had already been published revealing the identity of the mysterious animal—and the answer surprised even the researchers themselves.
Because it wasn’t a dog. And it wasn’t a real fox either. It was Dogxim—an extraordinary hybrid between a domestic dog and a pampas fox (Lycalopex gymnocercus), a South American fox-like canid that doesn’t belong to the “true” fox genus but to a separate genus within the dog family.
Two animals not only from different species, but from two entirely separate evolutionary genera, separated by 6.7 million years of evolution.
Her name, Dogxim, is a combination of the words Dog and Graxaim—the Portuguese name for the pampas fox. She looked like a creature engineered by mistake: A fox’s tail, sharp ears, a slender body but also dark fur, canine eyes, and semi-domesticated mannerisms.
The confusion only deepened when they observed her behavior. She barked like a dog but refused to eat dog food. She hunted mice, climbed shrubs, and at the same time played with toys and let people pet her.
“At times she allowed contact, even petting,” biologist Flavia Ferrari, who cared for her after she was found, told The Telegraph, “and sometimes she actually played with toys.”
To understand what they were dealing with, the researchers began with a basic test: A chromosome count. Dogxim had 76 chromosomes—right between the number of chromosomes in a domestic dog (78) and that of a pampas fox (74). But it wasn’t just the number—the shape, arrangement, and appearance of the chromosomes also reflected the genetic fusion between the two distinct animals.
In-depth DNA testing showed that her mitochondrial DNA (passed only from the mother) belonged to the pampas fox, while her nuclear DNA (from both parents) was a clear mix between fox and dog. “This was the first time evidence of a successful hybrid between two different genera in the dog family was found,” explained Dr. Rafael Kretschmer, a geneticist from the Federal University of Pelotas who participated in the research.
How could such a thing even happen?
In nature, animals almost always reproduce with members of their own species. Hybrids between species are rare—and between genera? Almost impossible.
Genetics usually don’t match: The chromosomes “don’t speak the same language,” and the result may be sterile, sick, or simply unfit for any environment.
But when humans enter the picture, everything changes. Pampas foxes live in areas that in recent years have been transformed into settlements, roads, and farmland—alongside abandoned or stray dogs. “Abandoning dogs is a criminal offense in Brazil, but it happens frequently,” explained Bruna Zanolzski, one of the researchers. The proximity between dogs and foxes, against the backdrop of environmental destruction and urbanization, likely led to the unusual encounter—and to Dogxim.
The end, for now, is a sad one. Dogxim died in 2023 of unknown causes, and it’s likely she didn’t have time to reproduce. She may remain a one-time case—but then again, maybe not. As nature is increasingly pushed to the margins and the boundaries between species blur, new questions arise: Will more hybrids like her appear in the future?
“This discovery suggests that even though these animals diverged nearly seven million years ago, they are still capable of producing viable offspring,” the researchers wrote.
If so, perhaps Dogxim wasn’t the end—but the beginning of something new, strange, and perhaps inevitable.