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 instance, cockroaches can lay hundreds of eggs but have a lifespan of less than a year. Similarly, mice give birth to dozens of offspring but only live for one or two years. In contrast, humpback whales, which give birth to a single calf every two to three years, can live for many decades.
These examples seem to reflect evolutionary strategies related to energy consumption for rapid reproduction, producing more offspring, or maintaining the life of an individual.
Queen ants can live for over 30 years. (Photo: Wildaboutants).
However, according to scientists, queen ants are an exception to this trend. Specifically, in some species of ants, the queen can live for over 30 years while laying thousands of eggs that hatch into worker ants within the colony. In contrast, non-reproductive female worker ants typically only live for a few months. Yet, under special circumstances for the benefit of the colony, worker ants in some species can become queens and significantly extend their lifespan.
Ecology Professor Laurent Keller at the University of Lausanne (Switzerland) stated: “Most studies on aging have been conducted on organisms with very short lifespans. However, ants present an intriguing subject for studying the aging process, as queen ants and worker ants in a colony often share the same set of genes 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 have pointed out that some queen ants produce a special type of protein that counteracts the aging effects of insulin, allowing them to consume more food to provide the necessary energy for egg-laying without shortening their lifespan.
The researchers indicated that insulin and the biochemical signaling system activated 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 receive and use glucose. Therefore, insulin fundamentally influences the energy available to cells. During this process, insulin also generates free radicals that can cause damage and other oxidative molecules as byproducts of metabolism.
Many researchers suspect this is why calorie-restricted diets that keep insulin levels low seem to extend lifespan in many species.
Insulin has significant implications 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 can live for about 5 years, while worker ants only live for 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 sense the change almost immediately due to the disappearance of the queen’s scent. Subsequently, if any worker ant is victorious in a competition for dominance, it will become a pseudo-queen.
The pseudo-queen not only mimics the behavior of 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 will eat more, its metabolism will change, and insulin levels will rise, triggering ovarian development. However, it is strange that increased insulin signaling would typically shorten lifespan rather than extend it.
Researchers have found that the secret to this phenomenon lies in insulin signaling. When insulin binds to its receptors on the cell surface, it triggers a series of responses within the cell, including two distinct chemical pathways. One pathway activates an enzyme known as MAP kinase, which is crucial for metabolic processes and ovarian development.
Additionally, the other pathway inhibits RNA synthesis, thereby shortening lifespan. However, in ants, the MAP kinase pathway operates while the other pathway does not.
Biologist Claude Desplan stated: “Imp-L2, a type of protein in ants, appears to protect the pathway that allows for 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 investigating whether they can extend the lifespan of this species by using Imp-L2 protein. Furthermore, the team hopes to experiment on mice to discover similar effects.