Ants talk by smell

 

A colony can include many millions of ants, yet queens have no intercom system to address their troops, and ants can't vocalize, anyway. So how do they coordinate all their complex collective behavior? Social media? (Antstagram, maybe?)Ants do have language, albeit not like we do. While humans rely heavily on voices and gestures, ants make sense by making scents. Pheromones are their main mode of communication, each containing a scent message that other ants in the colony can read with their antennae. They convey a wide range of information this way, and can even combine scents or use varying amounts of pheromone to add detail.

A scout who discovers food lays down a "scent trail" to help her nestmates, for example, and as they carry pieces home, they can add more scent to reinforce the signal. As the food source dwindles, they can modify the message again by releasing less and less scent on return trips, saving other ants a fruitless hike by posting real-time updates on how much food is left. Pheromones are used for countless other purposes, too, from identifying rank and health status to sniffing out intruders.