Seasonal cycles, phylogenetic assembly, and functional diversity of orchid bee communities

Abstract

Neotropical rainforests sustain some of the most diverse terrestrial communities on Earth. Euglossine (or orchid) bees are a diverse lineage of insect pollinators distributed throughout the American tropics, where they provide pollination services to a staggering diversity of flowering plant taxa. Elucidating the seasonal patterns of phylogenetic assembly and functional trait diversity of bee communities can shed new light into the mechanisms that govern the assembly of bee pollinator communities and the potential effects of declining bee populations. Male euglossine bees collect, store, and accumulate odoriferous compounds (perfumes) to subsequently use during courtship display. Thus, synthetic chemical baits can be used to attract and monitor euglossine bee populations. We conducted monthly censuses of orchid bees in three sites in the Magdalena valley of Colombia – a region where Central and South American biotas converge – to investigate the structure, diversity, and assembly of euglossine bee communities through time in relation to seasonal climatic cycles. In particular, we tested the hypothesis that phylogenetic community structure and functional trait diversity changed in response to seasonal rainfall fluctuations. All communities exhibited strong to moderate phylogenetic clustering throughout the year, with few pronounced bursts of phylogenetic overdispersion that coincided with the transition from wet-to-dry seasons. Despite the heterogeneous distribution of functional traits (e.g., body size, body mass, and proboscis length) and the observed seasonal fluctuations in phylogenetic diversity, we found that functional trait diversity, evenness, and divergence remained constant during all seasons in all communities. However, similar to the pattern observed with phylogenetic diversity, functional trait richness fluctuated markedly with rainfall in all sites. These results emphasize the importance of considering seasonal fluctuations in community assembly and provide a glimpse to the potential effects that climatic alterations may have on both pollinator communities and the ecosystem services they provide.

Retracted: Co‐fruiting plant species share similar fruit and seed traits while phylogenetic patterns vary through time

“…Rainfall shifts were represented by the absolute value of a rainfall differential D, which is calculated as R t – R t +1 (Ramírez et al . ), in which R t is the sum of rainfall at time interval t . Rainfall data were from available daily measurements in RNP (http://www.teamnetwork.org/).…”

“…We used generalized least-squares (gls) function in the NLME package in R to determine the relationships between the shifts in rainfall patterns and each community metric (NTI, NTI, species richness, expH), allowing for autoregressive correlation within our time-series data. Rainfall shifts were represented by the absolute value of a rainfall differential D, which is calculated as R t -R t+1 (Ram ırez et al 2015), in which R t is the sum of rainfall at time interval t. Rainfall data were from available daily measurements in RNP (http://www.teamnetwork.org/).…”

Seasonal patterns in species diversity across biomes

“…S30, S31), thus for any given year, we could not predict the pattern. This (Fogden 1972), green x are insects (Denlinger 1980), blue-green diamonds are lepidoptera (Owen 1969), blue triangles pointing down are orchid bees (Ram ırez et al 2015), dark blue squares with x are fish (Ansari et al 1995), purple snowflakes are fish (Barletta et al 2003), magenta diamonds with crosses are earthworms (Tondoh 2006). solid blue squares are butterflies (Devries et al 1997).…”

“…), blue triangles pointing down are orchid bees(Ram ırez et al 2015), dark blue squares with x are fish(Ansari et al 1995), purple snowflakes are fish(Barletta et al 2003), magenta diamonds with crosses are earthworms(Tondoh 2006). solid blue squares are butterflies(Devries et al 1997).…”

Seasonal changes in the assembly mechanisms structuring tropical fish communities

“…For example, the phylogenetic dispersion and functional richness of euglossine bee communities have been shown to change seasonally in response to rainfall patterns (Ramirez et al 2015). Animals can rapidly mediate competitive interactions through dispersal, suggesting that even over short temporal scales unrelated to successional stage, assembly mechanisms can vary in response to ontogenetic shifts in dispersal abilities, seasonal migrations, or intraannual changes in habitat availability.…”