Ant queens 'clone' males from different species, shattering biological norms

Nature's Rulebook Torn Asunder: Ants Revolutionize Reproduction

In a groundbreaking discovery that challenges our fundamental understanding of life itself, French scientists have unveiled a reproductive strategy in Iberian ants that is nothing short of astonishing. Researchers from the University of Montpellier observed that the queens of the Iberian harvester ant, Messor ibericus, engage in a behavior previously thought impossible: they not only mate with males of their own species but also with a completely different type of ant – the steppe harvester ant, Messor structor.

A Cross-Species Alliance for Survival

This remarkable interspecies affair is not a fleeting encounter. The Messor ibericus queens meticulously store and clone the sperm from their Messor structor partners. The resulting offspring are not simply hybrids; they are a complex blend, inheriting genes from the steppe ants while retaining the mitochondrial DNA of Messor ibericus. This intricate genetic tapestry is woven despite the fact that these two ant species diverged an astonishing 5 million years ago and do not naturally share the same geographic territories. It’s a biological paradox that has left scientists buzzing with excitement.

The Ultimate Domestication?

The implications of this discovery are profound. For the Messor ibericus queens, this reliance on Messor structor males is not just about genetic diversity; it's about survival and the perpetuation of their colony. These queens depend entirely on the steppe harvester ants for their workforce. This situation has been likened by the researchers to a form of domestication, a process usually associated with humans selectively breeding animals. As the lead researchers poignantly stated: “Living organisms are generally expected to produce offspring of their own kind. In this work, we report that this rule is broken by Messor ibericus ants, whose females have given birth to individuals of two different species. Messor ibericus queens strictly depend on Messor structor males, which is a well-differentiated, non-sister species. As far as we know, females cloning representatives of another species have not been observed before.”

A Calculated Biological Strategy

The scientific community is grappling with how this unprecedented strategy came to be. One key factor, according to the study, might be that Messor ibericus queens exclusively produce female offspring when mating with their own species. This limitation might have paved the way for this extraordinary cross-species adaptation. By raising cloned male offspring from Messor structor, the queens effectively secure their colony's labor force and, perhaps more critically, ensure a supply of mating partners for future generations of Messor ibericus queens. It’s a calculated gamble that appears to be paying off handsomely for the species.

Beyond Species Boundaries: Cloning on a New Scale

While instances of ants cloning males from their own species' sperm have been documented, this study reveals a phenomenon that shatters the perceived boundaries of species. “On an intraspecific level, several cases of male cloning by ants from the sperm of their own species have been noted. In this case, our results indicate that this phenomenon extends beyond interspecific barriers,” the researchers noted. They further elaborated, suggesting that these cloned Messor structor males should be characterized as a domesticated line. “While they meet all the criteria for domestication, the relationship we describe is closer and more complex than the most striking examples known to date.” This research, published in the prestigious journal Nature, rewrites the textbooks on ant reproduction and opens up thrilling new avenues for understanding the evolution of life itself.