Biology subjects

Buchmann, S. L.

Publications and source records attributed to Buchmann, S. L..

3 recordsLinked to original sources

bioRxiv2024

Buzz-world: Global patterns and drivers of buzzing bees and poricidal plants

Foraging behavior frequently plays a major role in driving the geographic distribution of animals. Buzzing to extract protein-rich pollen from flowers is a key foraging behavior used by bee species across at least 83 genera (these genera comprise [~]58% of all bee species). Although buzzing is widely recognized to affect the ecology and evolution of bees and flowering plants (e.g., buzz-pollinated flowers), global patterns and drivers of buzzing bee biogeography remain unexplored. Here, we investigate the global species distribution patterns within each bee family and how patterns and drivers differ with respect to buzzing bee species. We found that both distributional patterns and drivers of richness typically differed for buzzing species compared to hotspots for all bee species and when grouped by family. A major predictor of the distribution, but not species richness overall for buzzing members of four of the five major bee families included in analyses (Andrenidae, Halictidae, Colletidae and to a lesser extent, Apidae) was the richness of poricidal flowering plant species, which depend on buzzing bees for pollination. As poricidal plant richness was highest in areas with low wind and high aridity, we discuss how global hotspots of buzzing bee biodiversity are likely driven by both biogeographic factors and plant host availability. Whilst we explored global patterns with State-level data, higher resolution work is needed to explore local level drivers of patterns, but from a global perspective, buzz-pollinated plants clearly play a greater role in the ecology and evolution of buzzing bees than previously predicted.

ecology↗

bioRxiv2023

Microbial Metamorphosis: Symbiotic bacteria and fungi proliferate during diapause and may enhance overwintering survival in a solitary bee

Host-microbe interactions underlie the development and fitness of many macroorganisms including bees. While many social bees benefit from vertically transmitted gut bacteria, solitary bees, which comprise the vast majority of species diversity within bees, lack a specialized gut microbiome. Here we examine the composition and abundance of bacteria and fungi throughout the complete life cycle of a ground-nesting solitary bee Anthophora bomboides standfordiana. In contrast to expectations, immature bee stages maintain a distinct core microbiome consisting of Actinobacteria and fungi in the genus Moniliella. Diapausing larval bees hosted the most abundant and distinctive bacteria and fungi, attaining 33 and 52 times their initial copy number, respectively. We tested two adaptive hypotheses regarding microbial functions for overwintering bees. First, using isolated bacteria and fungi, we found that Streptomyces from brood cells inhibited the growth of multiple pathogenic filamentous fungi, suggesting a role in pathogen protection during the long period of diapause. Second, sugar alcohol composition changed in tandem with major changes in microbial abundance suggesting links with bee metabolism or overwintering biology. Our results suggest that Anthophora bomboides hosts a conserved core microbiome that may provide key fitness advantages through larval development and overwintering, and raises the question of how this microbiome is transmitted between generations. The present work suggests that focus on adult gut microbiomes in solitary bees may overlook microbial symbionts within brood cells that could play diverse roles in bee fitness, and that exploration of microbes associated with immature bees may uncover novel microbial effects on insect hosts.

ecology↗

bioRxiv2023

Individual variation in male pheromone production in carpenter bees correlates with size and sexual maturity.

Sex pheromones are species-specific chemical signals that facilitate the location, identification, and selection of mating partners. These pheromones can vary between individuals, and act as signals of mate quality. Here, we investigate the variation of male pheromones in the mesosomal glands of the large carpenter bee Xylocopa sonorina, within a Northern California population. We tested the hypothesis that morphological traits are correlated with the observed variation in chemical blend composition of these bees. We also conducted behavioral assays to test whether these male pheromones act as long-range attractants to conspecifics. We found that larger males with darker mesosomal glands have a higher pheromone amount in their glands. Our analysis also shows initial evidence that this pheromone blend serves as a long-range attractant to both males and females. We show that both male body size and sexual maturation are important factors influencing pheromone abundance, and that this pheromone blend acts as a long-range attractant. We hypothesize that this recorded variation in male pheromone could be important for female choice.

evolutionary biology↗