Termite mounds are iconic examples of earthen structures that can withstand the forces of nature such as weathering and remain intact for decades if not centuries. We have discovered that moisture alone, at levels close to the liquid limits of the construction soil, which is a residual red soil in Bangalore, is sufficient to give termite mound soils its incredible strength. However, in the absence of the manipulation of soil by termites, this soil has no weathering resistance. It is termite handling of the soil, and possible introduction of salivary additives, that imparts weathering resistance to these termite mounds that stand up to 7 feet tall in the IISc campus. 

The termite investigated in this study was the fungus-farming termite Odontotermes obsesus, a common termite in south India. 

This paper is an inter-disciplinary collaboration between the Centre for Ecological Sciences (Renee M. Borges and Nikita Zachariah) and the Department of Civil Engineering (Tejas Murthy). 

Link to publication: https://royalsocietypublishing.org/doi/10.1098/rsos.200485