Chemical signals - contact and airborne

In these cases, orientation of scouts is probably achieved without the use of pheromones. However, recruitment by tandem-running in Camponotus sericeus is guided by an orientation trail previously laid by scouts from their hind-guts (HOlldobler et al., 1974). 

Windborne chemical signals for recruitment, which are transmitted in a manner comparable with that of sex pheromones (see Section 15.6, and Carde, Chapter 5), are known in Novomessor species. When scouts discover large food sources, they release their poison gland secretions into the air, and other 

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