@article{701, author = {Paul Bardunias and Daniel Calovi and Nicole Carey and Rupert Soar and Scott Turner and Radhika Nagpal and Justin Werfel}, title = {The extension of internal humidity levels beyond the soil surface facilitates mound expansion in Macrotermes}, abstract = {
Termites in the genus\ Macrotermes\ construct large-scale soil mounds above their nests. The classic explanation for how termites coordinate their labour to build the mound, based on a putative cement pheromone, has recently been called into question. Here, we present evidence for an alternate interpretation based on sensing humidity. The high humidity characteristic of the mound{\textquoteright}s internal environment extends a short distance into the low-humidity external world, in a {\textquoteleft}bubble{\textquoteright} that can be disrupted by external factors like wind. Termites transport more soil mass into on-mound reservoirs when shielded from water loss through evaporation, and into experimental arenas when relative humidity is held at a high value. These results suggest that the interface between internal and external conditions may serve as a template for mound expansion, with workers moving freely within a zone of high humidity and depositing soil at its edge. Such deposition of additional moist soil will increase local humidity, in a feedback loop allowing the {\textquoteleft}interior{\textquoteright} zone to progress further outward and lead to mound expansion.
}, year = {2020}, journal = {Proceedings of the Royal Society B: Biological Science}, volume = {287}, language = {eng}, }