The Cornitermes cumulans termite species is abundant in the savannah regions of central South America. This species has been studied recently for its unusually laborious mound-building habits. Most mound-building termite species simply build additions onto their mound structures in order to accommodate their growing colony sizes. However, when C. cumulans colonies grow to the point where mounds need to be altered to accommodate more colony members, this species destroys previous mound structures before rebuilding properly sized mounds from scratch. These two mound-building methods have been known to researchers for several years. The first, and more common mound-building method mentioned above is referred to as “growth by addition,” and the second, and more complicated method, is known as “growth by reorganization.”
The growth by reorganization method is well documented in C. cumulans species, but the African termite species Macrotermes bellicosus, is also noted for resorting to this particular mound-building method. The reorganized mounds that are built by these two termite species always begin with the construction of a central chamber for the rearing of larvae. This central chamber is referred to as the “hive” or “habitacle,” and it remains in place during all three stages of mound reorganization. The first stage in mound reorganization sees the construction of a small subterranean chamber below the soil’s surface. This small chamber houses a small number of adults and numerous larvae during the earliest stage of C. cumulans’ colony growth. The second stage sees the walls surrounding the hive torn down and replaced with sturdier walls. At this stage, a small mound takes form above the soil’s surface. The third stage entails the construction of a large mound that protrudes from the ground at a height of four feet, and a minor subterranean portion. This final mound structure houses the many adult workers and soldier termites, while larvae are still nursed within a large hive below the ground. Unlike the first stage, the second and final stage sees a network of subterranean tunnels built below the mound and several chambers within the mound itself. The final stage also involves the construction of durable pillars that reinforce the mound’s structure. Before these pillars are constructed, the outermost wall of the mound must first be demolished. In order to ensure that the final mound remains durable enough to withstand environmental challenges, worker termites make use of hard clay as opposed to fine grain soil particles as construction materials.
Have you ever seen a nesting mound that was created by ants as opposed to termites?