The world’s first confirmed dog-fox hybrid has been found in the Brazilian wilderness.
The animal was hit by a car in the area of Vacaria in 2021 and taken to a veterinary hospital for treatment but staff were unable to conclude whether it was a fox or dog they were taking care of.
Up until now, there has been anecdotal evidence but never scientific proof that it could happen because of the difference between the two species.
Unusual physical characteristics, including some dog-like and some fox-like traits, piqued the interest of scientists from local universities who subsequently analysed her genes.
A recently published study revealed the animal’s mother was a pampas fox and her father a domestic dog of an unknown breed. It is the first recorded instance of a fox and dog breeding, experts believe.
It has the same build as a medium-sized dog, large, pointy ears, a long snout with a jet black nose and bulging brown eyes set into a thick, wiry black-brown coat with specks of white and grey throughout.
The young wild canid was given the names “graxorra” and “dogxim” by carers and researchers.
Academics also dubbed the animal “dogxim” as a merger of “dog” and “xim” from graxaim-do-campo.
The dogxim looked like both dog and fox, and also behaved in a strange way akin to both, the team noted. It refused food and ate live rodents; barked like a dog but had a thick, dark coat similar to the fox; and was wary of people but warmed to them over time.
“She was an amazing animal, really a hybrid between a pampas fox and a dog,” Flávia Ferrari, a conservationist that worked with the animal during her recovery, told The Telegraph. “It was not as docile as a dog, but it also lacked the aggressiveness expected of a wild canid when handled.
“She had a shy and cautious personality, generally preferring to stay away from people. Over the time she was hospitalised for treatment, I believe she started to feel safer.”
Genetic makeup
The animal was neutered as part of her treatment so scientists do not know if she would have been able to reproduce, but believe it would have been possible.
Scientists looked at the dogxim’s genes and found 76 chromosomes. Only one canid, the maned wolf, has this amount of chromosomes and it looks so different to the newly-discovered Brazilian animal that the scientists ruled it out.
A dog has 78 chromosomes and a pampas fox 74 and hybridisation of the two would produce 76 chromosomes. No other interspecies could produce the dogxim’s karyotype, the team says.
Mitochondrial DNA, which is passed down maternally in the cell’s energy-making capsules, revealed fox heritage. However, elsewhere in the genome were clear stretches of dog-like DNA.
“In our study we recorded the first case of hybridisation between one species of wild canid and the domestic dog,” study first author Bruna Elenara Szynwelski, a PhD student in genetics and molecular biology at Universidade Federal do Rio Grande do Sul.
“But, different to cases of hybridisation studied in North America, Europe, and Africa, this hybridisation occurred between species from the distinct genera: lycalopex and canis.”
Dr Rafael Kretschmer, a cytogeneticist who ran the genetic analysis, said: “She is not a new species; she is a hybrid individual between two different species: pampas fox and domestic dog.
“We consider her to be unique because it was the first case of hybridisation between pampas fox and domestic dog and the first case of hybridisation between dogs and wild canids in South America.”
The animal was cared for at the veterinary hospital of the Universidade Federal do Rio Grande do Sul, where she recovered fully and was then transferred to a conservation centre called Mantenedouro São Braz in Santa Maria city.
Hybrids have been seen before of domestic dogs and other wild species including coyotes, wolves and dingos.
The movement of the rare animal was organised by the region’s government. She died this year of unknown causes.