Pattern of ant diversity in Korea: An empirical test of Rapoport's altitudinal rule

Two diversity patterns (hump-shaped and monotonic decrease) frequently occur along altitude or latitude gradients. We examined whether patterns of ant species richness along altitudes in South Korea can be described by these patterns and whether ranges of ant species follow Rapoport's altitudinal rule. Ants on 12 high mountains (>1100m) throughout South Korea (from 33° N to 38° N) were surveyed using pitfall traps at intervals of 200–300m altitude. The temperatures at the sampling sites were determined from digital climate maps. Ant species richness decreased monotonically along the altitudinal gradient and increased along the temperature gradient. However, species richness of cold-adapted species (highland species) showed a hump-shaped pattern along altitude and temperature gradients. The altitude and temperature ranges of ant species followed Rapoport's rule. Sampling site temperature ranges were significantly correlated with coldness. Therefore, Rapoport's rule can be explained by high cold-tolerance of species inhabiting high altitudes or latitudes. Altitudinal diversity patterns of total ant species (a), warm-adapted species (b), cold-adapted species (c). [Display omitted] •Two diversity patterns (hump-shaped, monotonic decrease) occur along altitude.•Ants were surveyed at 12 high mountains in South Korea.•Richness of total and warm-adapted species showed the monotonic decrease pattern.•Richness of cold-adapted species showed a hump-shaped pattern along altitude.