In 2021, a mysterious animal was involved in a car accident on the streets of Brazil and was sent to an animal hospital. The reason why it is said to be mysterious is that the staff at the time could not determine what kind of animal it was. It looked like a dog and a fox. Judging from the appearance, it has the characteristics of both, with large and pointed ears, thick fur, and a slender nose.
It's the one that girls hold in their hands
Judging from its behavioral performance, it is very alert but not afraid of people. It allows people to touch itself and likes to eat live animals, such as rodents.
He is as active as a dog, likes to play with toys, and barks like a dog, but moves like a fox.
In order to determine what this mysterious creature is, scientists conducted genetic testing on it, and the results showed thatThis is a canine fox, that is, the offspring of a dog and a fox. Its mother is a Pampas fox and its father is a domestic dog.
This is the first certified dog-fox in Brazil and the first recognized dog-fox hybrid in the world, named "dogxim".
It is a pity that this dog has died now. What is even more regrettable is that,Scientists believe this is a fertile female offspring.
As soon as the news came out, foreign netizens couldn’t sit still:
"Breakthrough of reproductive isolation?"
"It's all fake. Are people so easy to deceive nowadays?"
"I wonder how it died."
"The cause of death is unknown? I think it might be caused by the experiment!"
All current comments mainly point to two aspects. One is questioning why the dog fox died. Did it die because of human experiments? Another questions whether reproductive isolation has really been broken.
As for the first question, I can’t answer it yet, but we can talk about the authenticity of the dog fox and how it came about.
Can dogs and foxes produce offspring?
It is well known that reproductive isolation exists between different species.
Reproductive isolation is generally based on physical isolation. Take the same species as an example. Two populations are forced to separate without any communication. In different environments, the two populations evolve and develop independently, and genetic differences will gradually appear.
When the genetic differences become larger and larger, the two populations will become reproductively isolated.
Australian Cattle Dog and Dingo Descendants
For two closely related species, the main factors for reproductive isolation are appearance, preferences, behavior, mating and courtship methods, etc.
To put it simply, if two birds with similar looks have a very special call (caused by genes), then the two parties may dislike each other because of their different calls, and they will not be able to see each other in the eye.
For species that are distantly related, reproductive isolation is even more obvious. In addition to the differences in life details mentioned above,The biggest difference may be the number of chromosomes.
Generally speaking, it is impossible for dogs and foxes to produce offspring. They are both members of the Canidae family, foxes belong to the genus Vulpes, and dogs belong to the genus Canis. They belong to the same family but different genera.
Most foxes have 50 chromosomes, while dogs have 78 chromosomes. The two are very different. It is impossible for gametes to combine and produce offspring.
If we follow the above statement, does it mean that the dog fox is fake?
No, the dog fox in the report is real.
Scientists tested this canine fox and found that it had 76 chromosomes. From this, it was deduced that its parents should be a fox with 74 chromosomes and a dog with 78 chromosomes, a Pampas fox and a domestic dog.
The Pampas fox is different from what we call foxes. Its other name is river fox, which belongs to the genus Pseudovus in the family Canidae.
It can be seen from this classification thatThe river fox is not a fox in the true sense. In comparison, it is more closely related to dogs on the genetic map. This is the main reason why they can combine to produce offspring.
So how do river foxes and domestic dogs produce the next generation?
The number of chromosomes in river fox cells is 74, and the number of chromosomes in dog cells is 78. The gametes produced by both sides are 37 and 39 respectively. When the two fuse, a dog fox with 76 is produced.
But reality is far from that simple. The combination of gametes from different species also needs to consider the compatibility of the gametes. There are still great differences between different species, and it is extremely rare for them to successfully fuse and grow up normally.
Take horses and donkeys, for example. Although both belong to the genus Equus, the probability of producing horses and mules is also very low. It takes many times over a long period of time to produce offspring.
After coupling, even if a mule is born, it does not mean that they have broken through reproductive isolation.
Because the main factors for breaking through reproductive isolation are: natural environment and fertile offspring. Mules are almost entirely produced with human help and are almost sterile.
It’s so difficult to find the same genus in the same family, let alone river foxes and dogs in the same family but different genus.
The offspring of a jackal and a dog in Russia
at last
In general, it is almost impossible for different species to produce the next generation of fertile individuals.
If we only talk about the ability to produce the next generation, then it is only possible if the genetic relationship is very close. In terms of probability, the probability of producing offspring from a hybrid of the same family and the same genus is definitely higher than that of the same family and different genus.
Just like a wolf and a dog, the probability of producing offspring after combining is definitely much higher than that of a wolf and a fox!
But nature is very magical, and it is not absolute. It will always create individual unimaginable "arts of art".
For example, a hybrid monkey was previously discovered in Borneo, which is believed to be the descendant of proboscis monkeys and silver leaf monkeys. They are two species in the same family and different genera. The most important thing is that this monkey was observed to have given birth to offspring.