Community Structure of Skipper Butterflies (Lepidoptera, Hesperiidae) along Elevational Gradients in Brazilian Atlantic Forest Reflects Vegetation Type Rather than Altitude

Abstract

Species turnover across elevational gradients has matured into an important paradigm of community ecology. Here, we tested whether ecological and phylogenetic structure of skipper butterfly assemblages is more strongly structured according to altitude or vegetation type along three elevation gradients of moderate extent in Serra do Mar, Southern Brazil. Skippers were surveyed along three different mountain transects, and data on altitude and vegetation type of every collection site were recorded. NMDS ordination plots were used to assess community turnover and the influence of phylogenetic distance between species on apparent community patterns. Ordinations based on ecological similarity (Bray-Curtis index) were compared to those based on phylogenetic distance measures (MPD and MNTD) derived from a supertree. In the absence of a well-resolved phylogeny, various branch length transformation methods were applied together with four different null models, aiming to assess if results were confounded by low-resolution trees. Species composition as well as phylogenetic community structure of skipper butterflies were more prominently related to vegetation type instead of altitude per se. Phylogenetic distances reflected spatial community patterns less clearly than species composition, but revealed a more distinct fauna of monocot feeders associated with grassland habitats, implying that historical factors have played a fundamental role in shaping species composition across elevation gradients. Phylogenetic structure of community turned out to be a relevant additional tool which was even superior to identify faunal contrasts between forest and grassland habitats related to deep evolutionary splits. Since endemic skippers tend to occur in grassland habitats in the Serra do Mar, inclusion of phylogenetic diversity may also be important for conservation decisions.

Relationships among taxonomic, functional, and phylogenetic ant diversity across the biogeographic regions of Europe

“…First, to solve the polytomies, we used ‘multi2di’ from R package ‘phytools’. Second, the tree was ultrametrized applying Grafen's Rho transformation to branch lengths (Carneiro et al ), we used the function ‘compute.brlen’ from R package ‘ape’. Although it would have been preferable to have consistent branch length estimates, these relationships remain unresolved for most insect groups, as well as for most animal and plant groups.…”

“…GLS models use simultaneous autoregression to estimate means. When appropriate, we used multiple contrasts to test whether the slopes of the relationships between branch lengths (Carneiro et al 2014), we used the function 'compute.brlen' from R package 'ape'. Although it would have been preferable to have consistent branch length estimates, these relationships remain unresolved for most insect groups, as well as for most animal and plant groups.…”

Butterfly fauna (Lepidoptera, Papilionoidea) in an ecotone between two biodiversity hotspots in Minas Gerais, Brazil

“…According to the list presented by Mielke et al (2012), the species of Pyrginae also sampled in this study Chiomara basigutta (Plötz, 1884), Cogia calchas (Herrich-Schäffer, 1869), Heliopetes omrina (Butler, 1870) and Viola viollela (Mabille, 1898) have preference for natural grassland habitats. Moreover, Hesperiinae (Hesperiidae) and Satyrinae (Nymphalidae) are more abundant in grassland habitats (Casagrande et al, 2012), probably because larvae of Hesperiinae feed exclusively on monocots (Carneiro et al, 2014), and those of Satyrinae almost exclusively on monocots (Peña & Wahlberg, 2008), which are poorly represented in the forest environment. Despite the fact that those feeding habits justify their abundance in the Cerrado vegetation, in the PESRM, almost 50% of the species of Hesperiinae and 30% of the Satyrinae were found only in the transition areas.…”

“…In the rainy season, when more species are active, adult females easily find new, soft, nutrient-reach leaves to feed the caterpillars (Iserhard et al, 2013). However, environmental characteristics, such as vegetation type, are more relevant than the temporal variation (dry and rainy seasons) in organizing species composition for Hesperiidae butterfly assemblages (Carneiro et al, 2014) and can also be relevant for the species composition of the other butterfly families.…”

Resilience of insect assemblages to climate change in mature temperate mountain forests of NE China

“…Studies of altitudinal gradients both in tropical (Axmacher et al, 2009, Rodríguez-Castañeda et al, 2010 and temperate regions (Hawkins & Porter, 2003, Zou et al, 2013 have highlighted changes in elevation and their associated shifts in climatic conditions to be key determinants of changes in insect assemblages. It nonetheless often remains unclear if the observed altitudinal turnover relates directly to climatic changes or is influenced by vegetation or habitat changes (Axmacher et al, 2009, Carneiro et al, 2014. In this context, ecological niche theory suggests positive links between the composition and diversity of plant assemblages and the respective patterns in both herbivorous and predatory taxa.…”