Species diversity in vertical, horizontal, and temporal dimensions of a fruit-feeding butterfly community in an Ecuadorian rainforest

Abstract

To test the hypotheses that fruit-feeding nymphalid butterflies are randomly distributed in space and time, a community of fruit-feeding nymphalid butterflies was sampled at monthly intervals for one year by trapping 6690 individuals of 130 species in the canopy and understory of four forest habitats: primary, higraded, secondary, and edge. The overall species abundance distribution was well described by a lognormal distribution. Total species diversity (?-diversity) was partitioned into additive components within and among community subdivisions (a-diversity and 8-diversity) in vertical, horizontal and temporal dimensions. Although community subdivisions showed high similarity (1 -/l-diversity/y-diversity), significant 8-diversity existed in each dimension. Individual abundance and observed species richness was lower in the canopy than in the understory. However, rarefaction analysis and species accumulation curves revealed that canopy had higher species richness than understory. Observed species richness was roughly equal in all habitats, but individual abundance was much greater in edge, largely due to a.single, specialist species. Rarefaction analysis and species accumulation curves showed that edge had significantly lower species richness than all other habitats. Samples from a single habitat, height and time contained only a small fraction of the total community species richness. This study demonstrates the feasibility, and necessity, of large-scale, long-term sampling in multiple dimensions for accurately measuring species richness and diversity in tropical forest communities. We discuss the importance of such studies in conservation biology. 0 1997 The Linnean Swiety of London ADDITIONAL

Beetle assemblages from an Australian tropical rainforest show that the canopy and the ground strata contribute equally to biodiversity

“…These patterns are likely to reflect the specific biology of the species concerned and may even change with season (Devries & Walla 2001), although we have not addressed this possibility here. Our finding that there was vertical stratification in the beetle assemblage concurs with those for other tropical forest insect taxa (Longino & Nadkarni 1990;DeVries et al 1997;Brü hl et al 1998;Rogers & Kitching 1998;Basset et al 2001;Schultze et al 2001;Tanabe 2002;Charles & Basset 2005).…”

“…Other canopy-ground comparisons within tropical rainforest have suggested that most insect activity is located in the top few metres of the canopy (Sutton et al 1983), and that insects are more abundant and speciose in the canopy than the understory (Basset et al 2001;Charles & Basset 2005). However, this contrasts with other studies on Lepidoptera and Formicidae which suggest that the ground layer is as speciose as the canopy (DeVries et al 1997;Brü hl et al 1998;Schultze et al 2001).…”

Species abundance patterns in an ecosystem simulation studied through Fisher’s logseries

“…(a) A highly diversified community, as Manu, produces a curve with a gentle slope; this is the same for Korup, BCI 1982, 1985, 1990, Lambir 1992, 1997, and Paso 1987, 1990 . An important repercussion of this dichotomy based on species richness is that a more diverse community provides more samples fitting the logseries, which has also been observed by ecologists [21,68,70].…”

“…Fisher's logseries has been widely used to approximate the species abundance distribution of a sample of a community [8,16,17,21,31,32,40,56,59,68,70]. For example in [69,70] Williams apply it to a sample of hawk-moths captured with a lighttrap in Nigeria (cf.…”

“…In the literature, observations have often been considered to be fitted or not by the logseries simply on the basis of a by-eye fit [8,21,68,70]. Statistically, the goodness-of-fit has been also widely evaluated using a basic v 2 test [16,17,21,31,32,40,56]. In the sequel, we will propose more precise definitions for the evaluation of the goodness-of-fit (cf.…”