The Queens of bombs they rest regularly during reproduction, probably to avoid an burnout: a study led byUniversity of California (USA) has shown that these founders of colonies take some regular breaksprobably to avoid the exhaustion before the arrival of the workers.
What are bombs and why they are important
As the Zoology Museum of Sapienza University of Rome explainsbombs are insects belonging to the family of Beeand present themselves as showy, big and noisy. I am pollinators of ecological and commercial importance in all regions with a temperate climate.
Speaking of temperatures, the bombs still have a wide distribution, from the arctic regions to those temperate with some species even in tropical areas: this for the capacity of the bombs of adjust the body temperature and keep it constant thanks to an internal “vibration” mechanism that allows them to generate heat, and to a cooling system through irradiation in their abdomen.
Unfortunately, however, climatic crisis, pollution, loss of habitat And intensive agriculture are putting to the test the resistance and adaptation capacity of all pollinating insects. In fact, they are not only the melliphere bees that pay the consequences of this real environmental emergency, even bombs.
In 2021, the Fish and Wildlife Service of the United States had indicated the American bomb (Bombus Pensylvanicus) among the three species that required further studies for admission to List of wild species at risk of extinction.
It was estimated, in fact, that The population of this insect had even decreased by 89% since 2002: if first his presence was in fact attested in 47 of the 48 continental states of the United States, in 2021 he had completely disappeared by at least eight of these (Maine, New Hampshire, Rhode Island, Vermont, Idaho, North Dakota, Oregon, Wyoming); In the state of New York alone, the population was drop by 99%while the regions of Southeast and of the Midwest they saw a decline greater than 50%.
And no, it’s not better now.
Because the queens of the bombs risk burnout and how they defend themselves
In the early stages of the formation of the colony, the queens of the bombs must really think of everything: they are looking for food, cure the prolers in development by heating it with the muscles of the wings, take care of the nest and lay the eggs. It is a high -risk game of balance: without the queen, the colony fails.
Still, the researchers noticed a intriguing rhythm: a gust of eggs followed by several days of apparent inactivity.
I noticed these breaks from the beginning, simply taking daily photos of the nests – says Blanca Peto, main author of the new study – it was not something I expected, and therefore I wanted to know what happened during those breaks
To find out what the breaks triggered, the scholar has monitored more than 100 queens for a period of 45 days In a controlled insectaire, documenting the nesting activity of each queen and carefully observing their distinctive broods, groups of eggs laid in “cups” covered with wax and immersed in pulline heaps.
The first observation was clear: in the whole population, many queens interrupted reproduction for several days, generally after a period of intense egg deposition. And the timing of these breaks seemed to align with the development phases of the existing brood.
To verify it, the researcher added experimentally to the nests brood in different phases, young larvae, more adult larvae and pupa, during the natural break of a queen. The presence of puppets, almost adult insects, pushed the queens to resume the laying of eggs within about 1.5 days. On the contrary, without additional broods, the breaks have stretched on average up to 12.5 days.
This suggests that the queens respond to the signals of their development offspring and consequently program their reproductive efforts.
There is something in the presence of puppets that signals that it is sure or necessary or start producing – explains Peto – it is a dynamic process, not a constant production as it was thought in the past
Eusocial insects, including bombs, present overlapping generations, a cooperative care of the brood and a division of work. Until now it has always been considered that these types of insects reproduce in all stages of development. This study challenges this conventional idea on bombs, whose reproductive behavior is more nuanced and intermittent.
This study has shown that the queen’s reproductive behavior is much more flexible than we thought. This is important because those first days are incredibly vulnerable. If a queen pushes too strong and too quickly, the entire colony may not survive
The study focused in particular on a single native species of the Eastern United States, but the implications could extend to other species of bombs or even other eusocial insects. Even the queens of other species could in fact slow down the rhythm during the foundation phases of the nest. If so, this innate rhythm could be a evolutionary trait Which helps the queens to survive long enough to create a workforce.
Several populations of bombs in North America are in decline, largely due to the loss of habitatexposure to pesticides and climatic stress. Understand the biological needs of the queens, the literal foundation of each colony, can help environmentalists a protect them better.
Even in a laboratory where everything is stable and must not look for food, the queens stop anyway. This tells us that it is not just a response to stress, but something fundamental. They are managing their energy intelligently. Without queens, there is no colony. And without colonies, we lose essential pollinators. These interruptions could be the real reason for the success of the colonies
The work was published on BMC Ecology and Evolution.
Sources: University of California / BMC Ecology and Evolution
