Plasticity of Soil-Dwelling Ant Nest Architecture and Effects on Soil Properties in Environments of Contrasting Soil Texture.

The architecture of an ant nest is species specific and can include structures to capture the sun’s radiant energy, foraging tunnels to shelter ants from predators and parasites, or vents to expel carbon dioxide and regulate temperature. We examined how nest morphology varied between subsurface environments composed of either coarse or fine soil texture. We predicted that ant nest morphology varies with soil texture due to differences in soil stability, moisture retention, and/or ease of excavation. Morevoer, these differences in morphology will influence the hydrological properties of the soil environment. We casted nests of a common ant species in Sand Ridge State Forest and Allerton Park in Illinois in coarse-textured soil and in fine-textured soil. After casting, nests were extracted from the soil, digitized with a 3-D scanner, and analyzed using 3-D geometric analysis software. We compared various nest properties such as total volume, width and height of chambers, degree of torsion of tunnels, and tunnel-chamber angle of intersection.  The resulting geometric data, along with data representing properties of the surrounding soil, was used to model ant nests’ effects on the soil environment. Our results suggest that soil type can influence nest architecture which in turn affects the hydrological properties of the soil.