Researchers from the National Geographic Society/Waitt Fund Grant have found an unusual “Marshal Plan for ants” where victors and vanquished cooperate after wars. To say that this finding was unexpected is putting it mildly. The ant species involved is a particularly aggressive type of ant, the African Acacia ant Crematogaster mimosae. These ants are famous for their painful stings and the ability to drive away elephants by stinging them inside their trunks.
Most of the wars are territorial, competing for resources. These are deadly serious wars, and they are all about survival. These tree dwelling ants make large nests, and protect the trees against predators. The problem with that is that the mathematics of one tree and two ant colonies naturally leads to conflict.
The much-bitten researchers, Kathleen P. Rudolph and Jay P. McEntee, discovered that after a war, even the winners were in bad shape. The usual high casualties mean that they can’t defend the tree properly. That, in turn, means that the colony can’t really function effectively. It seems that a series of chemical signals may be responsible for stopping the wars, and may somehow contribute to the peace process.
The solution is simple, elegant, and entirely unexpected. The victorious ants actually recruit their former enemies and work together. The two colonies cooperate, with both queens still alive. The losing colony, which is obviously in even worse shape, has everything to gain from this arrangement. It’s a good solution, it works, and both colonies survive.
One of the fascinating things about this finding is that the evolutionary logic is so good — “Don’t make a disaster worse.” I remember many years ago seeing a documentary in which a column of army ants encountered a column of leafcutter ants. The leafcutters, which are big ants, and almost as numerous as the army ants, would be hard targets in anyone’s language.
The researchers were interested to find that the ants apparently didn’t want to fight each other, and that the only casualty was one ant that tried to start a fight, which was promptly killed. The expected major battle never happened. (The documentary, of course, was totally ignored, and I can’t even find it on YouTube.)
It’s quite possible that highly evolved creatures like ants have built-in conflict resolution. Many ants, in fact, mimic human behaviour in tribal warfare, sizing each other up and displaying, before actually entering into a fight. If the odds don’t look good, the ants won’t fight.
Note — it has to be said that this more peaceful approach isn’t a universal rule. Many ant species are extremely aggressive, notably fire ants, and the famous slave-raiding ants. Some types of ants have evolved for war to the point where they can no longer feed themselves, and use captured slaves to physically feed them instead. Fire ants simply exterminate all other ants and take over their territories. Obviously, the genetic programming and adaptions of ant species have a lot to do with this type of behaviour.
The interoperation of colonies, however, raises another question — how super colonies evolved. Could it be, for example, that cooperation between ants led to the creation of super colonies? The classic ant colony has only one queen; super colonies have multiple queens. Generally speaking, in the traditional format, dominant queens wipe out their competitors. In super colonies, multiple queens are very good evolutionary move — the colony is virtually immortal, as long as the queens survive.
It’s not quite as strange an idea as it might seem — Apparently the ants take on the same odours and even bacteria, so that the former enemies eventually have the same chemical signatures as nest mates.
The findings in this study also raise a particularly important point about conflict in general, according to researchers:
Sorting out these processes could contribute to our understanding of an intriguing aspect of physical conflict — that animal combatants become more similar biologically through combat.
The human expression for this is “You become your enemy,” meaning that you adapt to the behaviour of your opponent. In practical terms, this also means that you acquire the abilities to offset the advantages of your opponent.
Taken to its logical extreme, remove the advantages and disadvantages which promote conflict, and cooperation replaces conflict. Can you think of another species which might benefit from this approach?
