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Different genes show different levels of expression variability. For example, highly expressed genes tend to exhibit less expression variability. Genes whose promoters have TATA box and initiator motifs tend to have increased expression variability. On the other hand, DNA methylation of transcriptional units, or gene body DNA methylation, is associated with reduced gene expression variability in many species. Interestingly, some insect lineages, most notably Diptera including the canonical model insect Drosophila melanogaster, have lost DNA methylation. Therefore, it is of interest to determine whether genomic features similarly influence gene expression variability in lineages with and without DNA methylation. We analyzed recently generated large-scale data sets in D. melanogaster and honey bee (Apis mellifera) to investigate these questions. Our analysis shows that increased gene expression levels are consistently associated with reduced expression variability in both species, while the presence of TATA box is consistently associated with increased gene expression variability. In contrast, initiator motifs and gene lengths have weak effects limited to some data sets. Importantly, we show that a sequence characteristics indicative of gene body DNA methylation is strongly and negatively associate with gene expression variability in honey bees, while it shows no such association in D. melanogaster. These results suggest the evolutionary loss of DNA methylation in some insect lineages has reshaped the molecular mechanisms concerning the regulation of gene expression variability.

Silviculture can be a powerful tool for restoring and enhancing habitat for forest-dependent wildlife. In eastern North America, regenerating timber harvests support abundant wildflowers that provide essential forage for native pollinators. Factors driving floral resource availability within regenerating forests remain almost entirely unstudied. Recent efforts to increase the area of regenerating forests (5 years old), but this pattern reversed by the end of the growing season. Ultimately, our study demonstrates that the abundance of flowers available to pollinators within regenerating hardwood stands varies with factors associated with advancing succession. Recognizing the potential trade-off between woody regeneration (i.e., saplings) and pollinator forage availability may benefit forest managers who intend to provide floral resources to flower-dependent wildlife like pollinators via silviculture. Key words: flower communities, blooming, regenerating forests, forest management, timber harvest, overstory removal, Pennsylvania, Appalachian, pollinator La sylviculture peut etre un outil precieux pour restaurer et ameliorer l'habitat des especes sauvages dependant de la foret. Dans l'est de l'Amerique du Nord, les coupes de bois en regeneration abritent d'abondantes fleurs sauvages qui fournissent un fourrage essentiel aux pollinisateurs naturels. Les facteurs qui determinent la disponibilite des ressources florales dans les forets en regeneration n'ont pratiquement pas ete etudies. Les efforts recents visant a augmenter la superficie des forets en regeneration (< 10 ans) par l'enlevement de l'etage dominant dans les Appalaches centrales offrent l'occasion d'etudier le developpement des communautes de fleurs sauvages forestieres apres l'elimination du couvert. Nous avons effectue 1 208 releves de plantes en fleurs dans 143 recoltes, enregistrant 1525 245 fleurs representant 220 taxons repartis dans 47 familles. Le nombre de fleurs dans les peuplements recemment recoltes etait negativement associe a la couverture de fougeres et de jeunes arbres, mais positivement associe a la couverture d'herbes et de ronces (Rubus spp.). Au debut de la saison de croissance, davantage de fleurs ont fleuri dans les peuplements en regeneration plus ages (par exemple, > 5 ans), mais cette tendance s'est inversee a la fin de la saison de croissance. En somme, notre etude demontre que l'abondance des fleurs disponibles pour les pollinisateurs dans les peuplements de feuillus en regeneration varie en fonction des facteurs associes a l'avancement de la succession. La reconnaissance du compromis potentiel entre la regeneration ligneuse (c'est-a-dire les jeunes arbres) et la disponibilite du fourrage pour les pollinisateurs peut profiter aux gestionnaires forestiers qui ont l'intention de fournir des ressources florales a la faune dependant des fleurs, comme les pollinisateurs, par le biais de la sylviculture. [Traduit par la Redaction] Mots-cles : communautes florales, floraison, forets en regeneration, gestion forestiere, recolte de bois, suppression de l'etage dominant, Pennsylvanie, Appalaches, pollinisateur, 1. Introduction Early successional forest has become an increasingly rare community across eastern North America over the past century (King and Schlossberg 2014; Albright et al. 2017). Mass clearcutting during [...]

Introduction: Bee conservation in the US is currently hindered by challenges associated with assessing the status and trends of a diverse group of >3000 species, many of which are rare, endemic to small areas, and/or exhibit high inter-annual variationin population size. Fundamental information about the distribution of most species across space and time, thus, is lacking yet urgently needed to assess population status, guide conservation plans, and prioritize actions among species and geographies. Methods: Using wild bee data from two public data repositories representing the contiguous US, we evaluated the availability and sufficiency of data for use in species assessments of wild bees. We also examined the number of bee species recorded in each US state and the proportion of species with recent records (2012-2021). Results: Although efforts to monitor bees continue to grow, there remains a massive paucity of data. Exceedingly few records (0.04%)reported both sampling protocol and effort, greatly limiting the usefulness of the data. Few species or locations have adequate publicly available data to support analyses of population status or trends, and fewer than half of species have sufficient data to delineate geographic range. Despite an exponential increase in data submissions since the 2000s, only 47% of species were reported within the last decade, which may be driven by how data are collected, reported, and shared, or may reflect troubling patterns of local or large-scale declines and extirpations. Discussion: Based on our analysis, we provide recommendations to improve the quality and quantity of data that can be used to detect, understand, and respond to changes in wild bee populations. [ABSTRACT FROM AUTHOR]

Behavioural variation is essential for animals to adapt to different social and environmental conditions. The Kinship Theory of Intragenomic Conflict (KTIC) predicts that parent‐specific alleles can support different behavioural strategies to maximize allele fitness. Previous studies, including in honey bees (Apis mellifera), supported predictions of the KTIC for parent‐specific alleles to promote selfish behaviour. Here, we test the KTIC prediction that for altruism‐promoting genes (i.e. those that promote behaviours that support the reproductive fitness of kin), the allele with the higher altruism optimum should be selected to be expressed while the other is silenced. In honey bee colonies, workers act altruistically when tending to the queen by performing a 'retinue' behaviour, distributing the queen's mandibular pheromone (QMP) throughout the hive. Workers exposed to QMP do not activate their ovaries, ensuring they care for the queen's brood instead of competing to lay unfertilized eggs. Due to the haplodiploid genetics of honey bees, the KTIC predicts that response to QMP is favoured by the maternal genome. We report evidence for parent‐of‐origin effects on the retinue response behaviour, ovarian development and gene expression in brains of worker honey bees exposed to QMP, consistent with the KTIC. Additionally, we show enrichment for genes with parent‐of‐origin expression bias within gene regulatory networks associated with variation in bees' response to QMP. Our study demonstrates that intragenomic conflict can shape diverse social behaviours and influence expression patterns of single genes as well as gene networks. [ABSTRACT FROM AUTHOR]

Understanding the ecological and evolutionary processes that drive host–pathogen interactions is critical for combating epidemics and conserving species. The Varroa destructor mite and deformed wing virus (DWV) are two synergistic threats to Western honeybee (Apis mellifera) populations across the globe. Distinct honeybee populations have been found to self-sustain despite Varroa infestations, including colonies within the Arnot Forest outside Ithaca, NY, USA. We hypothesized that in these bee populations, DWV has been selected to produce an avirulent infection phenotype, allowing for the persistence of both host and disease-causing agents. To investigate this, we assessed the titre of viruses in bees from the Arnot Forest and managed apiaries, and assessed genomic variation and virulence differences between DWV isolates. Across groups, we found viral abundance was similar, but DWV genotypes were distinct. We also found that infections with isolates from the Arnot Forest resulted in higher survival and lower rates of symptomatic deformed wings, compared to analogous isolates from managed colonies, providing preliminary evidence to support the hypothesis of adaptive decreased viral virulence. Overall, this multi-level investigation of virus genotype and phenotype indicates that host ecological context can be a significant driver of viral evolution and host–pathogen interactions in honeybees. [ABSTRACT FROM AUTHOR]