“Almost science fiction”: first animal seen to clone members of another species

A species of ant living in southern Europe is the first animal known to produce descent of another species. According to scientists, it seemed like a joke or something out of science fiction, but “it was really, really, really big.”

The queens of iberica produce cloned males Of a completely different species, breaking with the known rules of reproductive biology and suggesting that it may be necessary to rethink the limits that define the species.

The workers of the colonies of this species, Harvest of Ibericus, are all hybrid, and the queens need to mate with males of a distant speciesa Harvesting aid to keep the colony functional.

However, in a new one, published last week in the magazine Naturethe researchers found that some populations of M. Ibericus live in zones where there are no colonies of M. structor nearby.

“This was very, very abnormal. It was almost a paradox,” he told The Evolutionary Biologist Jonathan Romiguier, from the University of Montpellier, co -author of the study.

The team initially thought that it was a failure to collect samplesbut eventually identified 69 regions with this standard. “We were forced to face the facts and try to understand If there was something special In the colonies of Messor Ibericus, ”said Romiguier.

When trying to solve this puzzle, the team found that the queens of M. Ibericus also lay eggs that give rise to males M. structorthese are those who fertilize the workers.

This is the first time that an animal is observed from a given species capable of produce offspring of another species as part of your normal life cycle.

“At first, It was almost a joke inside the team”, Said Romiguier.“ But as the results emerged, it was no longer a joke and began to be a serious hypothesis”.

Conjugated, all these results show that the queens of M. Ibericus They are clone males of M. structorwithout transmitting any DNA nuclear yours. According to Romiguier, the next step is to identify the exact mechanism that allows this cloning and find out when maternal DNA is eliminated.

The ants are Eusocial insectsthat is, they live in colonies that function as Cooperative Super-Organismscompounds mostly by sterile females, the workers, and for a small number of reproductive females: the queens.

Males exist only to fertilize the queens During the bridal flight and die shortly after. Queens mate only once in their lifetime and store the sperm of this meeting in a special organ, then using it to lay eggs that can Originate queens, workers or males.

However, when the queens of M. Ibericus mate with males of their own species, can only produce new queens.

It is thought that this happens due the “selfish” genes of the queensin which the DNA of the males of M. Ibericus guarantees its survival throughout generations by forcing the larvae to become fertile queens rather than sterile workers-a phenomenon known as “real fraud.”

To avoid this, the queens need to use male sperm M. structor to generate the workers. This is why the existence of isolated and healthy colonies of M. Ibericus It looked like a real puzzle.

To try to find answers, the researchers analyzed 132 males of 26 colonies of Marcus Ibericus, to check if there were males of M. structor gifts.

They found that 58 had their body covered with hair and 74 were totally smooth. A genetic analysis of the nuclear genome of some of these males revealed that specimens hairy were M. Ibericus And the plain M. structor.

But This, by itself, did not prove that the queens were eggs of males of two different species; There could be some hidden queens of M. structor to produce these males.

Therefore, the team analyzed the Mitochondrial DNA (transmitted only by the mother) of 24 of these males of M. structor and found that vineyard of the same mother that the males of M. Ibericus of the same colony.

“It was this detail that made me think: ‘Maybe we are facing something, really, even big ‘“, These Romiguier.

Then the team isolated 16 queens in the laboratory and genetically analyzed the newly posted eggs; 9% of these eggs contained males of M. structor. Then they accompanied a weekly, for 18 months, a queen who was directly observed to produce males of the two species.

Denis Fournierevolutionary biologist and ecologist at the Brussels Free University, Belgium, who did not participate in the study, says that when he first heard her, the discovery It seemed “almost science fiction”.

“It is jaw -dropping! Most of us learn that the boundaries between species are firm, and here we have a system where ants regularly surpass them as part of their normal life, ”he told Live Science.

The team gave this new reproductive system the name of “Xenoparidade” – which means” birth of a different species. “

Romiguier said that it is not yet known for sure When this system emerged in the Iberian-certificate ants, but somewhere had happened among the evolutionary separation of M. Ibericus e M. structorabout 5 million years ago.

“Now that we know that such a system is possible, it is exciting to think that old and enigmatic data can suddenly begin to make sense in the light of this discovery,” concluded Fournier.

Eventually, the surprising discovery can even lead scientists to have to redefine what is a species.