Dorylus (Dorylus gribodoi), commonly referred to as driver ants, safari ants or siafu are a large insect genus belonging to the family of the army ants. This is one of the many insect species in Uganda, also found in other parts of East Africa, Central Africa, as well as tropical Asia. These insects are capable of stinging as a defensive mechanism, although they rely more on their strong shearing jaws and pincer-like mandibles, sharp enough to sever through skin.
Dorylus derives its ‘siafu’ name from the Swahili language and this is used in various Bantu languages, although with some little modification, to refer to the driver ant. The Baganda for example, call it ‘nsanafu’, a term quite similar to siafu.
Dorylus, like several ant communities, are very social and do not just exist as one but rather, live in large colonies of about 20 million insects and on some occasions, the number can even rise to 22 million. Each colony consists of a queen ant, workers, soldiers and drones (which only visit the colony during the mating season). Dorylus queens are very fertile and for this, they hold a world record of laying millions of eggs in just a month. On the other hand, most of the workers and soldiers are sterile females.
Although similar to army ants, drivers are relatively bigger with the queen being approximately two inches long while the workers are an eighth of an inch.
Driver ants are blind and thus communicate through ‘pheromones’ –where they secrete or excrete a chemical factor that triggers a social response in members of the same species. Pheromones vary from alarm, sex (courtship), food trails, and others.
The colonies are mobile (pastoral) as they temporarily nest in a location for about two to three weeks, building small anthills for habitats. Soon after that, they embark on another trek in search for food. For this reason, they are called safari ants to imply that they are always travelling. During their journeys, they form long lines and move in thousands as a way of defending themselves from enemies. Even in their nests, they form a protective shield; call it a fort, by linking together their bodies. This way, they protect themselves from any possible foes.
Driver ants are so aggressive and have exceedingly painful bites to which a number on animals fall victim, including humans too. It is the responsibility of the soldiers to provide a secure way for workers during the course of movement.
Driver ants are predators, feeding on other animals: small mammals, worms and many other invertebrates. As earlier mentioned, they possess exceptionally strong mandibles that enable them to rip and as a result, weaken their prey.
In traditional societies, where there is no access to modern medical facilities, the mandibles of these driver ants are used as makeshift surgical staples that can hold a wound together until it cures naturally. Also, they have been recognized for controlling pests as these comprise part of their diet.
Dorylus prefer to live in rainforests where their prey is in abundant supply, and can particularly be found nesting under logs, piles of leaves, anthills and other objects.
However, the ants have also been noted to be very dangerous to humans, just like they are to other animals. Their bites can inflict a lot of pain and in large numbers; they can even lead to deaths. This is especially in settlements that have been established in areas close to the ants’ range.
Driver ants are important to both the ecosystem and individuals but can also tend to be extremely hazardous. This implies that individuals have to be cautious when finding places to settle lest they encroach on the ants’ space and resultantly fall victim to them.
By Enid Karen Nabumati