Fig 5. Volume of soil excavated from 50 cm depth increments.

Volumes for 10 colony size classes based on 1000 cm² increments of total area. Data from Tschinkel [35]. No colonies of size class 9 were found. Volumes are the sum of chamber volume within each depth increment. Because chambers average 1 cm in height, volume and area are equal. Depth from which soil was excavated is coded by color, and these colors are used to weight the depth-composition of discs in Figs. 7 and 8.