Monday, 7 September, 2015
The termite mound has to be one of the most impressive constructions in nature. Few other animals make such imposing creations and none that are as small as the termite make something so big. Termites move an astonishing quarter of a metric ton of dirt to build these five metre high constructions and will keep moving that much each year to maintain it. The mound building termites collectively weigh about15 kilograms (and number roughly 2 million), which makes their efforts even more impressive.
The first thing we need to clear up is what the mounds actually are. Most people imagine them as being akin to an apartment block, with all the termites having little homes in there. The truth is that it is closer to an air conditioning unit than a habitation. See the thing is that termites are very sensitive creatures and need to live in very exact conditions. The mound is actually used to control the heat and humidity in the underground nest that is below the mound. Forget each termite having a little apartment with great views, the mound is made up of a complex network of vents that ensure that the underground nest stays the same temperature and humidity all year round no matter how much the outside conditions change. The design is a marvel. Oh, and they use a crazy fungus during construction that acts as an antibiotic, ensuring that they are protected from most diseases.
So the mound is a design and construction marvel. Many scientists have wondered exactly how the termite does it. Sure they have the numbers but even still, they are tiny and they are individually not the brightest, so how on earth do they create such incredible structures? It turns out that they use something that is called ‘swarm logic’ to build the mound. Each termite knows a number of basic rules, something that tells them ‘place dirt on left when x amount of dirt is on right’ or ‘a thousand termites follow this path and then the next thousand go this way’ and so on. They do not have the entire mound as a blueprint in their individual brains but rather have the rules that will enable a mound to be built. Scientists have used computer programs to simulate these rules and have found that they work. It means that while there are no foremen they are still able to construct these amazing structures.
One last aspect of interest is how they communicate with each other as this is a vital component of swarm logic. How do they know that a thousand termites have gone down one path? Well, termites use pheromones to communicate with each other. These are scent chemicals that enable them to convey messages in a way that is very useful for building the mound. As the termites move around they lay pheromones and they are able to detect concentrations, so that they know when a thousand termites have been down one path.
Posted in termites