Ecological Stoichiometry of Bumblebee Castes, Sexes, and Age Groups.

Ronalds Krams,Sergejs Popovs,Tatjana Krama,Jonathan Willow,Jorge Contreras Garduño,Māris Munkevics,Linda Dobkeviča,Indrikis A Krams

doi:10.3389/fphys.2021.696689

Abstract

Ecological stoichiometry is important for revealing how the composition of chemical elements of organisms is influenced by their physiological functions and ecology. In this study, we investigated the elemental body composition of queens, workers, and males of the bumblebee Bombus terrestris, an important pollinator throughout Eurasia, North America, and northern Africa. Our results showed that body elemental content differs among B. terrestris castes. Young queens and workers had higher body nitrogen concentration than ovipositing queens and males, while castes did not differ significantly in their body carbon concentration. Furthermore, the carbon-to-nitrogen ratio was higher in ovipositing queens and males. We suggest that high body nitrogen concentration and low carbon-to-nitrogen ratio in young queens and workers may be related to their greater amount of flight muscles and flight activities than to their lower stress levels. To disentangle possible effects of stress in the agricultural landscape, further studies are needed to compare the elemental content of bumblebee bodies between natural habitats and areas of high-intensity agriculture.

Highlights

Ecological stoichiometry focuses on the interactions of organisms with their environments, analyzing how ecological and evolutionary factors shape their bodies’ elemental composition (Sterner and Elser, 2002; Filipiak et al, 2017)
The present study investigated whether ovipositing queens, young queens, workers, and males of the buff-tailed bumblebee (Bombus terrestris) differ in their body C and N compositions and the C/N ratio, a reliable indicator of physiological stress across taxa (Hawlena and Schmitz, 2010a; Rinehart and Hawlena, 2020)
The ecological stoichiometry of bumblebees is linked with either stress levels experienced during their larval and pupal development, or possible differences with the functional roles of bumblebee castes during adulthood, both of which affect C and N concentrations in their bodies

Summary

Introduction

Ecological stoichiometry focuses on the interactions of organisms with their environments, analyzing how ecological and evolutionary factors shape their bodies’ elemental composition (Sterner and Elser, 2002; Filipiak et al, 2017). Ecological Stoichiometry of Bumblebees which in turn increases metabolic rate (Slos and Stoks, 2008; Hawlena and Schmitz, 2010a,b; Krams et al, 2013a,b) This increases the demand for carbohydrate-based fuel, containing high levels of carbon (C), and shifting the metabolic balance away from the anabolism that produces nitrogen (N)-rich proteins necessary for producing carbohydrates (Hawlena and Schmitz, 2010a,b; Trakimas et al, 2019). These complex processes generally increase the C/N ratio (Sterner and Elser, 2002; Hawlena and Schmitz, 2010a,b; Van Dievel et al, 2020)

Methods

Results

Conclusion