There are approximately 15000 species of ants, but the slave making phenomenon has been recorded in approximately fifty. Slave making simply refers to a queen building an army of ants by capturing or adopting ants in their pupa or larval stages. Mostly happens when warm so that pheromones can evaporate quickly. Moreover, rainy and overcast weather make the pheromones ineffective, yet it is the way ants communicate. The species by which this phenomenon has been observed is in the genus Formicoxenini. Others include Myrmoxenus ravouxi and T. unifasciatus. Slave making ants can either colonizes its own species or different species and it can be for a short while or forever. Those that are colonized for a short while can survive when free, but those that are facultative perish because they are totally dependent on the queen.
Slave making ants are parasites that seize other ants to grow their workforce. There are two types of slave, slave workers and parasite workers. Slave workers perform tasks for the new colony as if they were part of it originally. Parasite workers are tasked with bringing in more slaves by raiding other colonies. Slave making ants only make slaves from specific colonies. However, they can get slaves from other colonies, which is typical for social animals, such as ants. The slaves can be permanent, therefore depend on the slave masters their whole loves, or temporary where they only become salves for a short period of time.
An example of a slave maker ant is the Formica sanguinea. To start a colony, it invades a foreign nest and kills the queen. Most of the time. It invades a new nest if it is paralyzed. After the queen is dead, it makes the colony tend to her young. Afterwards, the workers will be set free to raid other nests. The raid is carried out so that pupa and larvae is brought from those nests to the slave maker’s nests. Due to the fact that ants learn their environment the first few days after hatching, the raided pupae will be born and become part of the new colony. They are then forced to become workers for the F. sanguinea. The raids are important for a slave making ant because not only do they provide labor, they also provide food. In case an ant dies during a raid, it is carried back to the nest where it can be eaten later. Raids usually take place when there is no rain because they reduce the effectiveness of pheromones, which is an important way by which ants communicate. The pheromones are very important, because the chemical released from the Dafour gland is used to kill an opposer. During a raid, the slaves and worker slaves’ fight and then they both transport pupae and larva top the queen’s nest. Depending on the species, the attacked nest can either flee or fight. In the species Proformica, they flee, due to the fact that they always lose fights.
The reproduction behavior is typical of other ants whereby there is a nuptial flight then the female invades a nest. In other cases, the female ant sends out mating signals to appeal to males. After mating, they immediately start looking for nests to take over. In one nest, only one species can be found in a Polyergus nest. This is different from other slave makers such as those of the genus Formica whereby two or three species can be found in the same nest working as slaves. How diverse a nest ends up0 is depdendent on the behavior of the queen or the choice slave ants kmake when raiding new nests. The Polyergus queen can either get a nest through adoption or budding. Adoption is whereby a female ant raids a nest and kills the queen. Afterwards, it adopts the ants in that colony to make them her workers. Budding is whereby a queen invades a nest with her colony and is accepted by the host colony as their new leader. After its eggs hatch, the new ants form part of its colony, making it bigger. The females who are hatched are tasked with increasing the number of the colony through reproduction.
The fertilized female mostly searches for a nest with pupae and this is done during the end of the summer when most ants are almost hatching. This is a strategic move, because she either drives way or kills all adult ants in that colony and takes over. After that, she waits patiently for the eggs to hatch. After that, she will have a colony, the ones she found there and the ones she will give birth to. After the eggs of the new colony hatch, they adapt to the smell of their environment. In this case, the queen ant will release chemicals that will indicate that she is in charge, hence, the ants will go on their businesses serving her, because they will think she is their queen. After she has a colony, she relaxes, and lays eggs because she will have an army to tend to her young. During a raiding party, the slave ants go together with the host ants. It is an effective strategy because if some of the host ants decide to split during the raid, they will be forced back into slavery by the slave ants. It is a way of ensuring that the colony stays as strong and big as possible. During the attack, slave ants use chemicals as a way of confusing host ants. Ants have a way of recognizing members of their colony, and it is through the hydrocarbons present on the cuticle. Raiding ants release formic acid which confuses the raided colony into fighting amongst themselves. Fatalities are few, because the fight seldom lasts long. However, if the host ants put up a resistance for a long time, there might be many fatalities.
However, slaves can overturn the tables and take over. All the slave ants do it stop tending to the young or bringing in food. As a result, the young ants die, reducing the number in the colony thereby weakening the queen. In other occasions, slave ants start a war and kill then young. Actually, most young ones raised by slaves die, compared to those that are raised free of captivity. A challenge they face is destroying the slave maker’s colony without touching their own colony. They do so via pheromones on their skins, and once the slave maker’s colony is done away with, it is easy to take over the nest. However, this is only possible if the ants were not born already colonized-it only works for raided ants. If they break free, ants that were colonized before they were hatched are more likely to die than those who were born in their own nests before they were raided. Actually, a research in the amazon showed that colonized ants starved to death after they were freed, even though food was presented to them in plenty. Revolt is an evolutionary feature, since the ants cannot reproduce after they are raided, therefore, even if they go free they aren’t of much importance. However, it can be said that it is purely instinctual to seek freedom. The struggle can last a while and causalities are man but in most cases, only the young die, and the nest becomes populated with raided ants and that is how they take over.
In conclusion slave making ants are a rare phenomenon in the ant kingdom. Factually, amongst the 15,000 known species of ants, it has been observed in only 50 species. They are an interesting bunch, because they make slaves out of other ants. They manipulate pupae before it is born, and if it is not enough, they raid foreign colonies and bring in pupae and larvae to join the army. It all starts with a wingless virgin queen who becomes fertilized. She then invades and kills the queen of a colony. She then feeds on the pheromones of the dead queen so as to mask her’s with then host queen’s pheromones. When the eggs hatch, the ants will think she is their queen and as a result, they work for her. To increase the numbers, she sends out raid parties to bring in larvae and pupae from other colonies. However, the slave ants can revolt by failing to feed the young ones or ousting an all-out guerrilla war.
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