Ants call for help even when they are larvae

Ants have a complex social system that requires communication between members of the colony. In addition to chemical signals, these animals also emit sounds to warn their companions of danger. Until now, these sounds had only been heard in adult ants, but a team of researchers from the Center for Ecology and Hydrology in Wallingford (United Kingdom), tohad just discovered that pupae, a pre-mature stage, also emit their own alarm bells.
In order to “scream”, some species of ants have a specialized beak on the abdomen that they can strike with their hind legs. In this way, animals warn, for example, when a predator is nearby. When ants are in the larval stage, their exoskeleton is not yet developed, so they lack the specialized beak and no sounds could be made. However, in the pupal stage, intermediate between the larval stage and the adult stage, the exoskeleton begins to be more developed and the beak could develop.
To test this hypothesis,the scientists used hypersensitive microphones and measured the sounds emitted by different individuals of the species Myrmica scabrinodis, both larvae, mature pupae and immature pupae. While the larvae and immature pupae were silent, the mature pupae made very rudimentary sounds.
The researchers, who publish their work in the journal Current Biology, found that these noises are also a kind of alarm bell. To do this, they reproduced the recordings of the pupae and verified thatthe adult ants walked towards the source of the sound and stood around, watching in an attitude of guard. However, when random sounds were played, the ants did not respond.
The research is another step towards understanding the complex network of relationships and forms of communication of social insects.