Density- and size-dependent spacing of ant nests: evidence for intraspecific competition.

We present three lines of evidence which each suggest that intraspecific competition has significantly influenced the spacing patterns of Formica altipetens colonies. First, nearest-neighbor analysis of nest spacing patterns detected significant uniformity in six of eight plots. Second, there was a signifcant increase in the distance separating nearest neighbors as ant nest diameters increased. Third, ant nest density predicted substantial variation in the colony dispersion index, indicating the existence of a dispersion continuum at our study site.