Dwelling in a flood zone is rarely straightforward, particularly in the event you’re a tiny insect with few avenues of escape. However the ants residing within the floodplains of the Alps and Pyrenees (a species referred to as Formica selysi) have developed a option to survive when waters rise: they seize onto one another and kind rafts that enable them to drift away with out being harmed. An necessary ingredient of these rafts, in line with analysis revealed Feb. 19 within the journal PLoS One, are the youngest members of the colony. These pupae and larvae have extra buoyancy than full-grown ants, and their involvement permits extra of the colony to outlive.
These “ant rafts” have been noticed earlier than, however researchers from the College of Lausanne and the College of Neuchâtel in Switzerland needed to grasp them higher. They gathered ants from a number of places and subjected them to laboratory flooding experiments. In every case, the employee ants shortly assembled into rafts, at all times inserting the apparently helpless and motionless younger brood pupae and larvae on the underside. The employee ants then distributed themselves all through the raft, whereas the queens at all times took the most secure place within the heart. (The ants within the experiments additionally had the choice of choosing items of buoyant wooden however at all times opted to make use of their younger relations as an alternative.)
The researchers write that this “swarm intelligence” takes benefit of brood buoyancy whereas preserving colony integrity and permits the overwhelming majority of the colony to outlive the flood. Not solely did the employee ants survive, nearly all of the brood did simply positive and later matured with out exhibiting any indicators of stress or harm from the floods.
You’ll be able to see this swarm intelligence in motion on this video, shot from under because the floodwaters approached:
Now these have been small experiments of solely about 60 ants at a time. As David Hu, a Georgia Institute of Know-how mechanical engineer who was not concerned within the research advised the Los Angeles Times, ant rafts within the wild can carry 100,000 or extra members of a colony. The floods within the lab additionally solely lasted a couple of minutes; in nature they will submerge colonies for days at a time. All the identical, the researchers write that that is an fascinating instance of social organisms making fast selections primarily based not on altruistic self-sacrifice however the “purposeful properties of people.”
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