Assembly Mechanisms of Neotropical Butterfly Communities Along an Environmental Gradient

Abstract

Our goal was to test the hypothesis that assembly processes that limit species similarity (i.e., competition) predominantly occur in more 'stable' abiotic environments, whereas habitat filtering (i.e., habitat characteristics) is a major driver of community composition within more variable environments at regional (e.g., aseasonal vs seasonal forests) and local scales (e.g., understory vs. canopy). A combined approach of phylogenetic-and functional trait-based analyses using forewing length and aspect ratio as traits, were used to this hypothesis. A 3-year survey was carried out at three sites (i.e., wet, transition and dry forests) across a climatic gradient in western Ecuador. Transition and dry forests were considered as seasonal, whereas wet forest were considered aseasonal. Butterflies were sampled using traps baited with rotting banana and prawn every two months from Nov 2010 to Sep 2013. Traps were set up at two heights, in the understory and canopy. DNA was extracted to sequence the barcode' section of the mitochondrial gene cytochrome oxidase 1 (COI) for phylogenetic analyses. Measurements of morphological traits, forewing length and aspect ratio were done using digital photographs of specimens. A total of 6466 specimens representing 142 species of Nymphalidae were recorded. Based on phylogenetic-and trait-based analyses, we rejected the hypothesis that assembly processes that limit species similarity (i.e., competition) are likely to predominantly occur in more 'stable' abiotic environments, whereas habitat filtering can be a major driver of community composition within more variable environments at regional (i.e., aseasonal forest vs seasonal forests) and local scales (i.e., understory vs. canopy). My study of assembly mechanisms revealed the opposite pattern, with stronger evidence for the action of ecological filters in the assembly of butterfly communities from the wet aseasonal forests, and competition likely to be a major assembly process within dry seasonal forests. The present study therefore provided new insights into community assembly mechanisms in one of the richest butterfly faunas worldwide.

Localização Remota, Classificação e Identificação das Erosões no Cinturão Verde de Ilha Solteira

“…Os valores para diversidade β1 demonstra que as espécies não estão distribuídas aleatoriamente dentro dos fragmentos de amostragem, visto que o interior dessas manchas são, em geral, ambientes mais heterogêneos que as áreas de borda, portanto, haverá diferença na presença de determinadas espécies ao passar do gradiente, devido à disponibilidade de recursos para as espécies, não só de cunho alimentar, mas a umidade, incidência de luz, pressões antrópicas e disponibilidade de plantas hospedeiras existentes em determinadas áreas desses ambientes também mudam (RIBEIRO 2006;HOEHNE, LORINI & RIBEIRO, 2017;RIBEIRO et al, 2008;HEPP, 2011). Checa et al (2019) afirmam que com insetos está distribuição possui um 12 padrão, onde haverá mudanças entre habitats abertos até os mais densos. Por outro lado, a persistência de espécies de borboletas não é só definida pela mudança no ambiente, mas a constante agravação desta modificação pode influenciar no comportamento do grupo (EHL et al, 2019).…”

“…A qualidade e quantidade de recursos (SILVA et al, 2017), os efeitos de processos histórico/evolutivos (LEAL et al, 2016;BEIRÃO et al, 2017) e a estrutura do habitat (NEVES et al, 2014;SILVA et al, 2016SILVA et al, , 2017 têm sido frequentemente considerados para explicar padrões de organização de comunidade naturais. Porém, pouco se conhece a respeito da variação espacial em regiões montanhosas, as quais vêm se mostrando como locais importantes para explicar a riqueza de espécies dentro de comunidades biológicas e ajudam a indicar habitats que precisam ser protegidos (MITTELBACH, 2012;CHECA et al, 2019).…”

What Do Butterflies Tell Us about an Intermediate Disturbance in a Dry Tropical Forest Context?

“…Some studies in disturbed ecosystems have found phylogenic overdispersal in sites with intermediate disturbance [13,14]. Nonetheless, there is also evidence that the disturbance generates an environmental filter that only allows for the growth of phylogenetically related species, and therefore, a phylogenetic grouping is generated [15,16]. However, in addition to richness, the behavior of the phylogenetic structure also has a pattern that cannot be extended to all taxonomic groups, and therefore, the impact of disturbance on dry forest butterfly communities is little known [15].…”