New research suggests ants build rafts out of other ants.
The queens ant is placed at the center of the brood of ants; the practice is believed to provide extra protection for the queen and minimize injury and death in the colony, a PLOS news release reported.
Social animals often work together to maximize survival in trying situations. Researchers already knew ants that live in flood plains create "living rafts," but little was known about the formation and social or physical structures of the rafts.
Researchers collected an ant colony from a flood plain in Switzerland and brought them back to the lab. The scientists simulated flooding on different combinations of worker ants, queens, and "broods" which contain larvae and pupae. The researchers were able to observe the hierarchy of the raft as well as its buoyancy and the ability of the ants to survive and recover.
The team found the worker ants were "extremely resistant to submersion," the news release reported.
"The workers protected the most vulnerable and valuable nest mate, the queen, by placing her in the center of the raft, and the worker ants used the buoyancy of the brood at the base and recovery ability of workers to create a raft and minimize ant injury or death," the news release reported.
Even the workers and broods at the bottom of the raft exhibited staggeringly high survival rates.
"We expected that individuals submerged on the base of the raft would face the highest cost, so we were astonished to see the ants systematically place the youngest colony members in that positions. Further experiments revealed that the brood are the most buoyant members of the society and that rafting does not decrease their survival; thus, this configuration benefits the group at minimal cost," Jessica Purcell from University of Lausanne, Switzerland, said in the news release.
