New study of Science magazine eLife, kiss seems to be used form of information exchange and message exchange. The habit of insects to exchange secretions from mouth to mouth, nutrition exchange {Trophallaxis} is an act that is not only in ants but also in bees. Until now it has been considered to sharing food. Nutrition exchanges include juvenile hormones that promote the growth of larvae in addition to the ingredients necessary for digestion, growth, fellow recognition and immunity.
It is considered that nutrition exchange is not simply food or digestive enzyme transmission, it is widely meaningful communication method with individuals. In other words, kissing has a important role that gives the necessary tools for surviving the communication and survival of colony.
In this study, not only ants, but also other insects, animals' nutrient exchange may have an unknown role have to be discover yet, and it seems to be a new frontier in knowing ecology.
Sciencemag article : http://www.sciencemag.org/news/2016/11/ant-s-kiss-may-hide-sneaky-form-communication