Recently, researchers have decoded the secret that allows queen ants to live significantly longer than worker ants.
According to researchers, in nature, species that reproduce in large numbers tend to have shorter lifespans, while those that reproduce less often tend to live longer. For example, cockroaches can lay hundreds of eggs yet live less than a year. Similarly, mice can give birth to dozens of offspring but typically live only one or two years. In contrast, humpback whales, which give birth to one calf every two to three years, can live for decades.
These examples seem to reflect evolutionary strategies and energy consumption aimed at either rapid reproduction and producing more individuals or maintaining the life of a single organism.
Queen ants can live over 30 years. (Photo: Wildaboutants).
However, scientists note that queen ants are an exception to this rule. Specifically, in some ant species, queen ants can live for over 30 years while laying thousands of eggs that hatch into worker ants in the colony. Conversely, worker ants, which are non-reproductive females, typically live for only a few months. Yet, in special circumstances, for the benefit of the colony, worker ants in some species can transform into queen ants and significantly extend their lifespan.
Professor Laurent Keller, an ecologist at the University of Lausanne in Switzerland, stated: “Most studies on aging have been conducted on organisms with very short lifespans. However, ants are an attractive subject for studying the aging process, as queen ants and worker ants in a colony often share the same genetic makeup but differ greatly in lifespan.”
What enables queen ants to have such a long lifespan? Recent research has revealed important details that contribute to the longevity of ants, particularly queen ants.
The secret to queen ants’ longevity
In the journal Science, researchers at New York University point out that some queen ants produce a special type of protein that counteracts the aging effects of insulin, allowing them to consume ample food to generate the energy needed for egg-laying without shortening their lifespan.
Researchers have identified that insulin and the biochemical signaling system triggered by ants are key regulators of the aging process. In fact, insulin is a hormone secreted by the pancreas that affects how cells in the body process and utilize glucose. Therefore, insulin fundamentally influences the energy available to cells. During this process, insulin also generates free radicals that can be harmful, as well as other oxidative molecules that are byproducts of metabolism.
Many researchers suspect this is why calorie-restricted diets that maintain low insulin levels seem to extend lifespans in various species.
Insulin holds significant meaning for ants. Specifically, biologists Claude Desplan and Danny Reinberg at New York University noted that evolution has rearranged some components of the insulin signaling pathway in ants. This may explain why queen ants live longer.
The hormone of queen ants helps them live longer. (Photo: Clint Penick).
These biologists have also studied the Indian jumping ant (scientific name: Harpegnathos saltator). In this species, queen ants live about 5 years, while worker ants live only about 7 months.
However, in this species, the difference in lifespan is not stable. If a queen ant dies or is removed from the colony, the worker ants can detect the change almost immediately, as the scent of the queen disappears. Subsequently, if any worker ant challenges for dominance in a power struggle, it can become a pseudo-queen.
The pseudo-queen not only behaves like a “queen” but also develops ovaries and can even lay eggs, extending its lifespan to 3-4 years.
When a worker ant becomes a pseudo-queen, it eats more, altering its metabolism and increasing insulin levels, which triggers ovarian development. However, oddly enough, this increased insulin signaling would typically shorten lifespan rather than extend it.
Researchers discovered that the secret lies in the insulin signaling. Specifically, when insulin binds to its receptor on the cell surface, it initiates a series of responses within the cell, including two distinct chemical pathways. One pathway activates an enzyme called MAP kinase, which is crucial for metabolism and ovarian development.
Moreover, the other pathway inhibits RNA synthesis and leads to a shortened lifespan. However, in ants, the MAP kinase pathway is active, while the other pathway is not.
Biologist Claude Desplan stated: “Imp-L2, a type of protein in ants, appears to protect the pathway that facilitates metabolism while inhibiting the pathway that leads to aging.”
Since conducting genetic experiments on fruit flies is easier than on ants, this research team is exploring whether they can extend the lifespan of fruit flies using Imp-L2 protein. Additionally, the team hopes to conduct experiments on mice to uncover similar effects.
