Have you heard of the “ant death spiral? It’s a phenomenon wherein army ants circle round and round until they die of exhaustion. Army ants communicate using pheromones or chemical scents. When they fail to follow the scent trail left by other ants, they will break from the crowd and go around in circles.
Army ants — unlike most other ant species — are blind. They also lack permanent nesting sites. Instead of living at a single site, army ant colonies are constantly on the march en masse looking for food. As the first ant in line travels it leaves behind a pheromone trail that other ants sniff out and follow. When this system works well, it allows foraging parties lead larger groups back to food. When it doesn’t work, the ants follow these pheromone trails as they flow back into each other, ending up in an endless loop that they follow to their doom. If the circle isn’t broken for some reason, they will probably never escape.
Although there are more than 200 species of army ants living on both sides of the globe, genetic evidence indicates that they may all have common ancestors and have kept their evolutionary advantages and disadvantages for more than 100 million years.
Credit : Treehugger
Picture Credit : Google
