Ants are highly social and they must work together to provide food and shelter for the entire colony. It has recently been discovered that there is no set hierarchy on the importance of these aspects, as ants are capable of learning from previous experience to assess a current situation and determine what is most important at that time. 

Takao Sasaki and Stephen C. Pratt from Arizona State University’s School of Life Sciences have published their findings in Biology Letters. The study was focused on Temnothorax rugatulus, an ant species native to the west coast of North America, stretching from British Colombia, Canada down to Arizona in the Sonoran Desert. 

Ants have many options to consider when looking for a new place to live. While the preference for a nest includes a small entrance and low light levels, the perfect home might not be available. The researchers gave the ants less-than-ideal options: some ants had to choose nests based on consistent light levels with multiple entrance sizes, while others were given uniform entrance sizes and light levels were altered.

While house-hunting, humans may have to tradeoff between things like yard size and proximity to a highway. Similarly, the ants had to decide what was more important: light or entrance size. The research team knew the ants would have to make compromises, but what was unexpected was finding that the ants would choose future houses based on past experiences. Some ants who had previously valued a small entrance over higher light  did not always repeat that choice during later housing choices. While not all of the colonies made new decisions, a significant amount had used previous nests to determine what did or did not work for the colony.

This level of intelligence has not been previously described in ants. Colonies make collective decisions with no leader to direct the masses toward a particular nest. According to the researchers, this phenomenon bears a resemblance to individual neurons that will collectively make decisions in the brain. We know that it happens, but we just don’t know how.

Future research will go deeper into exploring ant behavior to better understand how individuals work together for the betterment of the colony. This could have important parallels in understanding how humans work together to make decisions that benefit large groups.