Ant colonies are often cited as the model for social co-operation, with individuals working together for the benefit of the colony, rather than for selfish promotion of their own individual genes. But that isn’t the case claim researchers from the University of Leeds and the University of Copenhagen.

It seems that ants can be as sneaky as humans, since Dr. Bill Hughes and Professor Jacobus Boomsma have found evidence that certain ants are able to cheat the system, ensuring that their offspring become reproductive queens rather than sterile workers.

It had been thought that a larvae’s chance of becoming queen was purely a matter of luck, but the researchers have found that it largely depends upon who its father was – A handful of breeding males pass on a genetic advantage that give their offspring a much better chance of growing up into a queen, instead of being condemned to the life of a worker.

Dr Hughes explained:

The accepted theory was that queens were produced solely by nurture: certain larvae were fed certain foods to prompt their development into queens and all larvae could have that opportunity, but we carried out DNA fingerprinting on five colonies of leaf-cutting ants and discovered that the offspring of some fathers are more likely to become queens than others.

These ants have a ‘royal’ gene or genes, giving them an unfair advantage and enabling them to cheat many of their altruistic sisters out of their chance to become a queen themselves.

The mechanism by which male ants are able to pass on an unfair advantage to their offspring remains unclear, but researchers believe they must limit themselves intentionally, because these ‘royal’ genetic lines were always rare in each colony.

If too many larvae grew into queens, it could upset the balance of the colony, reducing its survival prospects. Additionally, the imbalance would be noticed by the “commoner” workers, who might then kill the surplus.

Queen leaf-cutter ants have multiple matings and are able to store the sperm throughout their lives. It is thought that males who pass on the “royal gene” to their offspring, mate with lots of females but provide only a small quantity of sperm each time. This way they have many offspring, but spread throughout several colonies.

Dr Hughes added:

The most likely explanation has to be that the ants are deliberately taking steps to avoid detection. If there were too many of one genetic line developing into queens in a single colony, the other ants would notice and might take action against them. So we think the males with these royal genes have evolved to somehow spread their offspring around more colonies and so escape detection. The rarity of the royal lines is actually an evolutionary strategy by the cheats to escape suppression by the altruistic masses that they exploit.

Dr Hughes and Professor Jacobus Boomsma said the royal gene discovery, published in the journal Proceedings of the National Academy of Sciences, debunks the notion of unadulterated egalitarian cooperation within ant colonies.

When studying social insects like ants and bees, it’s often the cooperative aspect of their society that first stands out

However, when you look more deeply, you can see there is conflict and cheating – and obviously human society is also a prime example of this. It was thought that ants were an exception, but our genetic analysis has shown that their society is also rife with corruption – and it’s royal corruption at that.

You might also enjoy reading:-

• Four Types of ‘Love’
• Male dominance no guarantee of genetic success
• New theory in Evolutionary Biology: Flexibility beats Fitness
• The lost tribes
• Sexuality could be genetically wired into the brain

Posted by Jonathan in Biology, Sociobiology

No Comments »