Ontogeny examines the development of a slave-making ant’s anatomical and behavioral features and how they mature throughout their lifetime and changes in response to the shifting nature of their environment.

Closely related ants probably have closely related signaling molecules, and coevolution is thought to have led to a kind of arms race to create a distinct colony signaling chemical making a separate distinction between the hosts and parasites (Topoff 1990).  The development of new colony odors is variable to change over a slave-making or slave-made ants lifetime depending on the number of times they either incorporate host colonies in to their captured network of ants, or undergo a power transition of being overtaken by other slave-making ant colonies, respectively.

Dulotic slave making ants and host ants coevolved while living together in the same anthill. While it is not fully known how roles within the ant colony might have changed, if at all, over time, it is clear that there is a present break down of the many jobs within merged colonies after enslavement. The role an ant - either slave-making or slave-made - has been observed to change and develop over their lifetime once slave-making ants have captured or colony or a captured colony comes under slave-making ant management. The development of the role of scout in slave-making ants and the raising of captured ants to transition from free-living to slave-made ants is very important for the cohabitation of the two ant colonies to continue functioning and withstand raids from other social parasite ant colonies in the same local area. Scouts have the function of choosing between weaker and stronger ant colonies, and it is suggested that the targeting of stronger ant colonies increases over a scout’s lifetime, suggesting an increase in aggression that is hypothesized to be linked to the development of colony odor. Every ant colony is understood to have a specific scent, however newly hatched ants do not have this scent, rather it develops as they mature and integrate chemicals in their environment to project their colony odor. From this observation, it is possible that this change in odor may develop and intensify over an ant’s lifetime as raiding and scouting continues.


Figure 1. Slave-made worker ants vs. slave-making worker ant differences in size and characteristics. Slave-made ants rarely get the amount of food resource they need, and depending on when in their lifetime they are invaded by these parasites developing without this may stunt their growth even further in their pupae to younger stages of growth.

Slave-made ant scouts and are more vulnerable to being preyed upon during these scouting missions, whereas the slave-making ant scouts are much more likely to kill adult worker ants during raids (Franks&Scovell 1983). It has been suggested from previous research investigating the behavioral differences between geographically different ant species from New York, West Virginia, and Vermont that ecology and/or surrounding aggressiveness of other colonies may affect overall behaviors observed in slave-making ant colonies within a local region. In some cases slave rebellion of the L. longispinosus ants is seen to increase, as they systematically kill P. americanus larvae at higher rates. Reasons for this increase in pupae-cide are not fully detailed, but from the research we have read, we believe it might be related to the frequency of successful raids by their slave-making captors. In contrast to this the P. americanus ants have been observed to have behavioral changes in the amount they fight over food more aggressively and kill more adult worker ants in the colonies they raid. This could be mediated by environmental pressures such as less resources being available during certain times, or an increase or decrease in slave-making ant colonies within their local vicinity. However more research is needed to understand any exact geographical or behavioral motivations for these behavioral changes in ants.   

Queen’s Strategy Over Her Lifetime
Bouts of feeding of the queen by other slave-making ants lasts much longer than bouts of food exchange from the slave-made ants. Queen of slave-making ants exchanges far more often with her own ants so that there is less competition among ants of her kind to become queen, i.e. her daughters threaten her fitness by being dominant workers. It was mentioned before that there was a relationship between food resources and reproductive fitness, this is described by the dominance behavior of the P. americanus in having to fight shorter times with Leptothorax and other host ants, whereas the host ants have longer fighting times over food amongst each other. This influence on food competition dominance is postulated to develop in host ants as they transition from free-living to slave-made ants, i.e. as time passes they fight less when competing against their cohabiting slave-making ant counterparts and expend more energy competing with their related Leptothorax mates. It might be that fighting times change depending on food resources, however more research using high and low food conditions in a cohabiting slave-made ant colony is needed.