Original Article: https://blog.theanimalrescuesite.greatergood.com/dog-fox-dogxim/

In 2021, an injured animal was brought to an animal rehabilitation center in southern Brazil. At first glance, it appeared to be a dog.

As veterinarians delved deeper into its behavior and genetic makeup, they uncovered an astonishing secret — it was the world’s first known dog-fox hybrid, aptly named ‘Dogxim.’

The Bizarre Encounter

While Dogxim barked like a dog, it sported long, fox-like ears and exhibited behaviors more akin to the Pampas fox, National Geographic reported. Even more perplexing, it refused typical dog food, instead opting for a diet of rats.

This enigmatic creature piqued the curiosity of caretakers, leading them to suspect it might be a hybrid—a blend of domestic dog and a local wild canid.

A Hybrid Species Unveiled

To confirm their suspicions, the caretakers sought the expertise of geneticists Thales Renato Ochotorena de Freitas and Rafael Kretschmer from the Universidade Federal do Rio Grande do Sul. Their study confirmed what was previously unimaginable—the animal was indeed the world’s first documented fox-dog hybrid, Dogxim. This revelation astonished experts in animal genetics and fascinated the global community.

“For us biologists and veterinarians, it is normal to look at all animals differently. We’re trained to look for what’s common and what’s different when we look at an animal. And that’s what happened,” researcher Cristina Araujo Matzenbacher told Newsweek. “She had eyes resembling a domestic dog, and long ears resembling a pampas fox, although she had a dark coat and barked like a dog.”

An Extraordinary Genetic Puzzle

The genetic puzzle began to unravel as scientists examined Dogxim’s chromosomes. As Science Alert reports, she possessed a total of 76 chromosomes, a significant clue. The maned wolf, the only canid in the region with 76 chromosomes, was ruled out as a potential parent due to differences in appearance and behavior. Further analysis revealed that while a domestic dog has 39 chromosomes and a Pampas fox has 37, Dogxim’s 76 chromosomes suggested hybridization. Mitochondrial DNA testing confirmed her mother was a Pampas fox, while nuclear DNA showcased a blend of dog and Pampas fox genetics.

“So far, we have no scientific evidence that there are other hybrids in this region. However, we suspect that this case we have described is not the only one,” Bruna Szynwelski told Newsweek. “Once biologist Herbert Hasse Junior observed two animals with an unusual phenotype in nature in 2019, it is likely that one of these animals was the female hybrid that was run over in 2021, and the other animal was never seen again.”

How did Dogxim’s Unique Hybridization Come to Be?

Environmental changes could have played a pivotal role, as the grassy plains of southern Brazil, home to Pampas foxes, have been drastically reduced over recent years. Human activities, such as cattle ranching and housing, led to the overlap of domestic dogs and Pampas foxes, increasing the opportunities for mating. The practice of abandoning dogs in natural areas also contributed to this phenomenon.

Implications for Wildlife Conservation

While hybridization is typically rare and unlikely to establish new populations, it raises concerns from a wildlife conservation perspective. The existence of hybrids like Dogxim could affect native fox populations, potentially introducing diseases and genetic weaknesses. The hybrid’s distinct appearance and adaptation challenges in natural habitats pose further threats to survival.

Dogxim’s Legacy

Dogxim sadly passed away in 2023. Her existence, though perhaps a singular occurrence, raises critical questions about the impact of hybridization on wildlife conservation. As reported by The Conversation, researchers believe that studying the consequences of hybridization on genetics, ecology, and behavior is essential to enhance the conservation of species in the face of environmental disturbances.

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Source: The Animal Rescue Site Blog