Queen ant makes males of another species for daughters to mate with

Some of the eggs laid by the ant of Iberian beams contain males of another species, the manufacturer’s harvesting anthill – and these men father of all workers in the colony.

“This statement really seems, really crazy, as impossible,” explains Jonathan Romiguier at the University of Montpellier in France. And yet, he discovered, it’s true.

Romiguier has become intrigued by Iberian harvest ants (Messor Ibericus) When he discovered that all workers Mr. Ibericus The nests were hybrids, with about half of their DNA corresponding to that of the harvester ant (Strutor Messor).

The most likely explanation, it seems, was that M. ibericus The queens mined with M. structure males. This kind of thing occurs in certain other ants of ants. No one knows why, but there are two competing explanations that seem to be most likely. One is that the hybrids of closely related species benefit when the genes of each species compensate some of the defects of others, a concept known as hybrid vigor.

Another possibility is that it could solve a particular problem M. ibericus Share with another kind of harvester ant: each time M. ibericus The queens mate with M. ibericus The males, all their offspring become queens. This may be due to a genetic oddity which ensures its own inheritance but which is devastating for the colony, which needs workers to survive. Breeding with another species can be a way to get around this.

However, M. ibericus The colonies occur in many regions of the Mediterranean region where there is no M. structure Colonies, including on the island of Sicily. However, Romiguier and his colleagues found a few strange hair M. structure men M. ibericus nests. So where did they come from?

The genetic analysis of strange males has provided a confusing index. A very little DNA which is inherited only from the mother, the mitochondrial DNA, in these structure The males were the only song to which clearly belonged M. ibericusrevealing that their mother was a M. ibericus queen.

This suggests that an egg of a M. ibericus The queen may contain a male of another species. To test this idea, Romiguier brought dozens of M. ibericus colonies in his laboratory. “It was very difficult, because in laboratory conditions, it is almost impossible to have men,” he says. “We had something like 50 colonies and watched them for two years without a single man was born. Then we were lucky.”

With three M. structure Males born in the laboratory, the evidence was undoubtedly: M. ibericus The queens produced males of the two species. The only possible explanation for this seems to be that the queen ants clone the M. structure Sperm males stored in a specialized organ called Spermatheca. Resulting eggs are almost entirely devoid of M. ibericus DNA, with the exception of mitochondrial DNA, which is absent from sperm.

This also explains where M. structure The sperm comes from: by producing two species of men, the queen ensures that her daughters who become themselves can mate with men of the two species. They use Mr. Ibericus cum to make new queens, while M. structure sperm is used to produce hybrid workers and new M. structure males.

There are some examples of other animals – including certain ants, clams and stick insects – where the eggs of a female are diverted by the sperm of a male of another species, which eliminates the DNA of the egg and the force to produce an unrelated individual. However, this only benefits men. This is the only known case of males and women of different species that depend on each other to reproduce.

“THE M. ibericus The queens absolutely need their clonal men. Otherwise, they cannot have workers, ”explains Romiguier. And the clonal Mr. Strctor Men need M. ibericus The queens reproduce and the hybrid workers to survive – there is no evidence that they are accompanied by their own species.

Although the results seem almost incredible, they convinced other experts. “The authors did a very rigorous study of the ants in question,” explains Nathan Lo at the University of Sydney. “Their results strongly support their conclusions.”

He suspects that because clonal males never mix genes with other lines, they gradually accumulate bad genetic changes which they cannot get rid of. “So, at some point, the line can start to deteriorate, especially since the environments change.”

Romiguier applies that this particular situation could possibly collapse. But as much as it seems that these M. ibericus women and M. structure The males may have painted themselves in an evolutionary corner with their dangerous affair, for the moment, their appointment seems to be a success-they have spread throughout the Mediterranean region, in large areas where M. structure The colonies have never succeeded.

Safari insect and ecosystems: Sri Lanka

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