Life and Nomadic Cycles of Army Ants
Army Ants reproductive life cycle starts with the queen of the colony laying a sexual or asexual crop of eggs. When the queen lays her eggs, she marks the beginning of the beginning of the stationary phase. These eggs are carefully taken care of by young worker ants since the development of the eggs is very delicate. The workers move each of the eggs to the middle of the bivouac where they remain until they hatch. After the eggs hatch, the new larvae are now the brood of the colony and the hatching of the eggs signals the start of the nomadic nights for the colony. This nomadic condition is induced to support the need for a high fat diet needed for the brood to properly develop. The worker ants now take care of the new brood as they would with the eggs, but the new brood also requires food. These larvae require a lot of care since are unable to move because they lack legs and have a small mouth that is incapable of chewing food. To feed the brood the worker ants must chew the food themselves and then regurgitate it so they can feed the brood by mouth to mouth; this method of feeding is called trophallaxis. Adult ants also use this method to share food amongst themselves, click here to find out more about the nutrition of an ant. In addition, workers will moderate the temperature for the brood by taking them to different parts of the bivouac at different times of the day to favor development. After the larva grow to maturity and transition into pupae they begin to undergo a metamorphosis into adult ants. At this point the ants transition back to the colonies stationary condition, the queen lays another batch of eggs, and the cocoons containing pupae are in are moved to the outer edges of the bivouac to metamorphose. Once the metamorphosis is complete and the ants begin to eclose, emerge from their cocoons, the new adults help other members within their cocoons emerge as well. As the new members are emerging the new eggs begin to hatch into larvae and the nomadic condition is begun again. Check out another organism with a complex life cycle the fungus Amanita phalloides (The death cap).
Most broods are produced by queen ants through parthenogenesis, the development of eggs without fertilization, is typically what the queen ant does when laying eggs for the next generation of ants. The offspring of these asexual broods consist purely of females because the genetic material required for a male is not in her body. These females from the asexual brood will all mature into new workers for the colony. However, sexual broods are laid from time to time when the queen is inseminated by a male of another colony. When this happens the queen lays a brood with both male and female offspring. To ensure the queen has the ability to produce more sexual broods in the absence of another male the queen is able to store the sperm from the previous male in a special organ. The new generation typically contains approximately 1500 males out of the typical 80,000 offspring which grow up quite differently from the other females. These males are much more developed than their female counterparts and each male larvae may consume up to 50 times more food than their females counterparts. These males become a large stress on the colony because of their huge size and appetite. During their growth the colony does not begin its regular nomadic phase because the male larvae is to large to be carried. In addition, during the sexual broods lifespan the colony itself is in a hunting frenzy to try and met the enormous needs of the large males. Throughout the males lives they do not contribute to the colonies maintenance functions and are eventually forced out of the colony to search for a queen with which to mate.

Finding a Mate
Upon leaving the colony the male army ants use their wings to search for a colony of the same species. This journey is extremely dangerous for the males who are alone and possess very weak mandibles. However, these males do possess strong eyes to search out ants of the same species with which to mate. Once the male finds another colony of Eciton hamatum army ants the male must be accepted into the colony before he can mate with the queen. The worker ants of the new colony must accept this new male into the colony to mate with their queen. The workers select for a male that closely resembles their own queen and thus let the new ant into the colony. This mimicry grants the male access to the queen and is finally able to mate. Mating for the male though is lethal, since the organ which contains the sperm cells bursts inside the queen and results in the death of the ant within the next 48 hours.

New Queens
In a sexual brood, females that are given a plentiful food supply for maximum nutrition will reach sexual maturity resulting in the formation of a new queen. Workers that take care of the queen, in the parent colony, through out its development bond with the queen through chemical scents and will eventually leave with her. When the new queen is ready she will leave the parent colony with her workers to form a satellite colony of her own. For up to a week workers from the parent colony and the satellite colony will travel back and forth between the two. After the new colony increases in size and numbers the new colony will not recognize the parent colony and the two may fight if the colonies cross paths.

In the case a new queen in the presence of an old queen the young queen will not leave the colony. The queens nearing the end of its life cycle often will be replaced by a new queen which will take over the colony with which it resides and continue in the queens place.

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