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Bacteriophages are the most numerous, ubiquitous, and diverse biological entities on the planet. Prior studies have identified bacteriophages associated with pathogenic and commensal microbiota of honeybees. In this study we expand on what is known about bacteriophages from the lineages Caudoviricetes, Inoviridae, and Microviridae, which are associated with honeybees (Apidae, Apis mellifera), solitary bees of the genus Nomia (Halictidae, Nomia), and hoverflies (Syrphidae). The complete genomes of seven caudoviruses, seven inoviruses, and 288 microviruses were assembled from honeybees (n = 286) and hoverflies in Arizona (n = 2). We used bacterial host predictive software and sequence read mapping programs to infer the commensal and transient bacterial hosts of pollinating insects. Lastly, this study explores the phylogenetic relationships of microviruses sampled from bees, opportunistically sampled pollinating insects such as hoverflies, and blackflies. 

Abstract Honey bees are important organisms for research in many fields, including physiology, behavior, and ecology. Honey bee colonies are relatively easy and affordable to procure, manage, and replace. However, some difficulties still exist in honey bee research, specifically that honey bee colonies have a distinct seasonality, especially in temperate regions. Honey bee colonies transition from a large society in which workers have a strict temporal division of labor in the summer, to a group of behaviorally flexible workers who manage the colony over winter. Furthermore, opening colonies or collecting bees when they are outside has the potential to harm the colony because of the disruption in thermoregulation. Here, we present a simple and affordable indoor management method utilizing a mylar tent and controlled environmental conditions that allows bees to freely fly without access to outdoor space. This technique permits research labs to successfully keep several colonies persistently active during winter at higher latitudes. Having an extended research period is particularly important for training students, allowing preliminary experiments to be performed, and developing methods. However, we find distinct behavioral differences in honey bees managed in this situation. Specifically learning and thermoregulatory behaviors were diminished in the bees managed in the tent. Therefore, we recommend caution in utilizing these winter bees for full experiments until more is known. Overall, this method expands the research potential on honey bees, and calls attention to the additional research that is needed to understand how indoor management might affect honey bees. 

Animals must learn to ignore stimuli that are irrelevant to survival and attend to ones that enhance survival. When a stimulus regularly fails to be associated with an important consequence, subsequent excitatory learning about that stimulus can be delayed, which is a form of nonassociative conditioning called ‘latent inhibition’. Honey bees show latent inhibition toward an odor they have experienced without association with food reinforcement. Moreover, individual honey bees from the same colony differ in the degree to which they show latent inhibition, and these individual differences have a genetic basis. To investigate the mechanisms that underly individual differences in latent inhibition, we selected two honey bee lines for high and low latent inhibition, respectively. We crossed those lines and mapped a Quantitative Trait Locus for latent inhibition to a region of the genome that contains the tyramine receptor geneAmtyr1[We use Amtyr1 to denote the gene and AmTYR1 the receptor throughout the text.]. We then show that disruption ofAmtyr1signaling either pharmacologically or through RNAi qualitatively changes the expression of latent inhibition but has little or slight effects on appetitive conditioning, and these results suggest that AmTYR1 modulates inhibitory processing in the CNS. Electrophysiological recordings from the brain during pharmacological blockade are consistent with a model that AmTYR1 indirectly regulates at inhibitory synapses in the CNS. Our results therefore identify a distinctAmtyr1-based modulatory pathway for this type of nonassociative learning, and we propose a model for howAmtyr1acts as a gain control to modulate hebbian plasticity at defined synapses in the CNS. We have shown elsewhere how this modulation also underlies potentially adaptive intracolonial learning differences among individuals that benefit colony survival. Finally, our neural model suggests a mechanism for the broad pleiotropy this gene has on several different behaviors. 

Animals are constantly bombarded with stimuli, which presents a fundamental problem of sorting among pervasive uninformative stimuli and novel, possibly meaningful stimuli. We evaluated novelty detection behaviorally in honey bees as they position their antennae differentially in an air stream carrying familiar or novel odors. We then characterized neuronal responses to familiar and novel odors in the first synaptic integration center in the brain–the antennal lobes. We found that the neurons that exhibited stronger initial responses to the odor that was to be familiarized are the same units that later distinguish familiar and novel odors, independently of chemical identities. These units, including both tentative projection neurons and local neurons, showed a decreased response to the familiar odor but an increased response to the novel odor. Our results suggest that the antennal lobe may represent familiarity or novelty to an odor stimulus in addition to its chemical identity code. Therefore, the mechanisms for novelty detection may be present in early sensory processing, either as a result of local synaptic interaction or via feedback from higher brain centers.