A new study has revealed that ants can switch between a worker status and a queen-like status by changing a single protein within their brains.

Philadelphia biologists have isolated nerve cells of Harpegnathos saltator, an Indian jumping Ant brain. They got their name because they can leap several inches. 

The experts found that the protein, called Kr-h1, orchestrates ants’ transition from a standard worker, tasked with finding food, and a queen-like ‘gamergate’. 

Gamergates have been described as being ‘queen-like’ even though they aren’t queens. In reality, they are workers who can reproduce even if there is no queen.    

Harpegnathos saltator (sometimes called the Indian jumping ant) is found in India. A worker is pictured here in an aggressive display (open mandibles) aimed at the photographer. Gamergates can reproduce, while workers can't

Harpegnathos saltator, also known as the Indian jumping Ant or Harpegnathos salator is found in India. This is an image of a worker in an aggressive display with open mandibles, aimed at the photographer. While gamergates have the ability to reproduce, workers are not.


Gamergates are worker ants that can reproduce sexually. Gamergates have been described as “queen-like”, even though they aren’t queens.  

Workers in the Indian jumping Ant have the potential for becoming reproductive gamergates. However, this process is hindered when the queen is present. 

After the death of the queen, there is a time of fierce fighting, and then a small number gain reproductive rights. 

These gamergates show dramatic social changes within their colony. 

But, you can reverse these changes and convert a newly formed gamergate back into a worker. 

The study was conducted by biologists at the University of Pennsylvania Perelman School of Medicine and published in the journal Cell.  

Roberto Bonasio, a study author, stated that animal brains can be plastic. This means they are able to change the structure and function of their brains in response to changes in the environment.

‘This process, which also takes place in human brains – think about the changes in behaviour during adolescence – is crucial to survival, but the molecular mechanisms that control it are not fully understood.’  

Workers maintain an ant colony by fighting intruders and finding food, while the queen is responsible for laying eggs. 

H. saltator has the ability to produce reproductive gamergates. However, this is impeded by the queen. 

After the death of the queen, there is a time of fierce fighting. After which, some individuals are granted reproductive rights and can become gamergates. 

The colony’s social behavior changes dramatically during these gamergates 

But, you can reverse these changes and convert a newly formed gamergate back into a worker. 

MailOnline: Professor Bonasio stated that Queens are born as queens. “When they eclose [emerge as an adult from the pupa or as a larva from the egg]They have wings. 

Harpegnathos saltator is pictured here with its prey in Wynaad, India. Any Harpegnathos female, adult worker can be converted into a 'queen-like' gamergate in the absence of the queen

Here is Harpegnathos saltator, pictured together with its prey in Wynaad (India). If the queen is absent, Harpegnathos women can convert into gamergates that look like queens.

“Gamergates” are people born as workers without wings and become queen-like when their social conditions change. 

To avoid petty falls the second time around, ANTS use their memory 

Ants are can learn to avoid danger after just one risky experience, according to a 2020 study. 

The insects can link visual cues with negative experiences and memorise potentially dangerous routes, the team of authors from the University of Toulouse found.   

Experiments revealed that two species of ants from Australia were successfully tested: Melophorus bagoti and Cataglyphisfortis. 

The insects changed their behavior to stay out of a pit during a second attempt at reaching their nest.    

As they approached the trap, some of the ants first stopped to scan their environment, before making a detour around the pit and safely reaching the nest.  

Learn more: Ants can use their past memories to stay out of trouble

Although it is well-known that Harpegnathos adult can change from being a worker to becoming a gamergate has not been explained. 

To learn more, the team developed a method for isolating neurons – nerve cells – from the ants and keeping them in plastic dishes in the lab. 

This allowed researchers to isolate neurons and study how these cells responded to hormones called juvenile hormone (JH3) or ecdysone (20E).

These hormones can be found in different amounts in both gamergates and workers. 

JH3 and JH3 produced different patterns of gene activation within the brains of gamergates and workers, according to researchers. 

Ants that are less dependent on JH3 than those with more 20E will act like workers. But ants who have more JH3 but less 20E behave like gamergates. 

However, the most surprising thing was how both hormones activated Krh1 in nerve cells. 

This protein reduces the gamergate behavior in workers and suppresses it in gamergates.  

In this manner, Kr-h1 protein acts a little like a switch and hormones turn it on/off.  

Shelley Berger from the University of Pennsylvania, said, “This protein regulates various genes in workers, gamergates, and prevents the Ants performing “socially inappropriate behavior.” 

“That’s to say that Kr-h1 must be maintained to preserve the borders between social castes. It also needs to make sure workers keep working while gamergates act like queens.  

The Kr-h1 protein would be eliminated from the ant brains of worker ants. Gamergates will start to behave like workers and worker ants like gamergates.  

Professor Bonasio explained that he had never imagined the protein would silence multiple genes in different castes’ brains. This could, therefore, lead to worker behaviours in gamergates as well as gamergate behavior in workers.  

Graphical abstract from the paper illustrates the process. Left is a worker ant (which finds food and fights invaders); right is a 'queen-like' gamergate (which reproduces). More JH3 and less 20E makes ants act like workers, while less JH3 and more 20E makes ants act like gamergates

This graphic is an abstract of the paper. Left is a worker ant (which finds food and fights invaders); right is a ‘queen-like’ gamergate (which reproduces). While ants are more likely to act as workers if they have less JH3 or 20E, ants with less JH3 will behave as gamergates if there is less of both 20E and JH3.

“We believed that the jobs would be given to multiple factors. Each of these brains only has one.

“The main message here is that at least for ants multiple behaviour patterns are specified in the genome. This means that gene regulation may have an enormous impact on what behavior that organism performs.

“In other words: Dr Jekyll’s and Mr Hyde’s parts are written in the genome. Everyone can take either of these roles depending on the gene switches that are activated or disabled.  

Professor Bonasio suggests that similar proteins may have the same functions in complex brains such as those of humans. 

‘Discovering these proteins might allow us to one day restore plasticity to brains that have lost it – for example, aging brains,’ he said. 

The researchers will continue to study the roles of Krh1 in organisms and how environment influences gene regulation, behaviour, and brain plasticity.  


In 2017, scientists led by Professor Roberto Bonasio genetically engineered ants to lack their sense of smell.

This affected the insects’ ability to communicate, forage or compete to be a queen, as their antennae and brain circuits failed to fully develop. 

The pheromones, which are secreted chemicals that stimulate responses in ants, allow them to communicate with each other. 

These odours can be used to signal readiness for mate, warn of predators approaching, provide a path to food and indicate social status. 

These signals can be received by ants because of the presence of proteins known as odorant receptors in their antennae. Each protein is designed to attach to an odorant chemical. 

An ant’s brain must have both the right odorant receptor and Orco protein. 

They were successful in engineering the genetic deletion of Orco protein. This resulted is ants who could not perform most, if any, of pheromone based social interactions. 

Particularly, they spent most of their time roaming outside of the nest unlike the other nestmates with the modifications. The colony was not able to communicate with them (a behavior called “spacecadet”) and they were incapable of foraging and returning food to their nest.

Mutant females also stopped grooming males as a pre-mating behavior. Our current research focused on Harpegnathos Saltator, an Indian jumping ant. This is unusual among ants species as only the queen has the ability to mate with the next generation. 

Any Harpegnathos female, adult worker can be converted into a ‘queen-like’ gamergate in the absence of the queen. The queen secretes an epheromone which suppresses workers’ ability to mate and lay eggs. 

After winning several antenna duels, the queen can be removed and the more aggressive females will undergo the transition. They then have the opportunity to continue producing progeny which is vital for the survival of the colony. 

According to a 2017 study, Orco was found to be ineffective for females’ ability to process pheromones. This makes them less likely engage in duels.