The ethics of theft:Reevaluating the impacts of floral larceny on plant reproductive success

Plants and their interaction partners offer unparalleled views of evolutionary ecology.Nectar larceny,entailing nectar extraction without pollinating,is thought to be an example of a harmful,antagonistic behavior,but the precise consequences of floral larceny on plant reproductive success remain contentious.We conducted a comprehensive meta-analysis of 153 studies across 120 plant species,using 14 moderators to assess the effects of floral larceny on plant reproductive success and examine the key moderators.We found that floral larceny negatively impacts flower traits,pollinator visitation,pollen deposition,and fruit set,while having a neutral effect on critical female fitness indicators,such as seed set and seed quality,as well as on male fitness.By altering pollinator behavior,floral larceny may reduce geitonogamy,potentially enhancing genetic diversity.Additionally,factors such as pollinator type,plant mating system,and pollen limitation were identified as key moderators of these effects.Our analysis reveals an ultimately neutral effect of floral larceny on plant reproductive success,with potential benefits in certain contexts.These findings suggest that floral larceny plays a complex and multifaceted role within plant-pollinator interactions,facilitating the evolutionary stability and coexistence of floral larcenists and host plants.

Future directions in Systematics: A report from the 4th Systematic Biology Forum in China

The 4 th Systematic Biology Forum,China took place in December 2019,covering a vast array of topics across animals,bacteria,fungi,plants,and viruses in the fields of systematics and evolutionary biology.Here,we discuss the emergent themes of this meeting and how these and other interdisciplinary research programs can be synthesized to better understand evolution in a systematic framework.

An integrative bioinformatics pipeline shows that honeybee-associated microbiomes are driven primarily by pollen composition

The microbiomes associated with bee nests influence colony health through various mechanisms,although it is not yet clear how honeybee congeners differ in microbiome assembly processes,in particular the degrees to which floral visitations and the environment contribute to different aspects of diversity.We used DNA metabarcoding to sequence bacterial 16S rRNA from honey and stored pollen from nests of 4 honeybee species(Apis cerana,A.dorsata,A.florea,and A.laboriosa)sampled throughout Yunnan,China,a global biodiversity hotspot.We developed a computational pipeline integrating multiple databases for quantifying key facets of diversity,including compositional,taxonomic,phylogenetic,and functional ones.Further,we assessed candidate drivers of observed microbiome dissimilarity,particularly differences in floral visitations,habitat disturbance,and other key environmental variables.Analyses revealed that microbiome alpha diversity was broadly equivalent across the study sites and between bee species,apart from functional diversity which was very low in nests of the reclusive A.laboriosa.Turnover in microbiome composition across Yunnan was driven predominantly by pollen composition.Human disturbance negatively impacted both compositional and phylogenetic alpha diversity of nest microbiomes,but did not correlate with microbial turnover.We herein make progress in understanding microbiome diversity associated with key pollinators in a biodiversity hotspot,and provide a model for the use of a comprehensive informatics framework in assessing pattern and drivers of diversity,which enables the inclusion of explanatory variables both subtly and fundamentally different and enables elucidation of emergent or unexpected drivers.

Testing the systematic status of Homalictus and Rostrohalictus with weakened cross-vein groups within Halictini(Hymenoptera:Halictidae)using low-coverage whole-genome sequencing

The halictid genus Lasioglossum,as one of the most species-rich bee groups with persistently contentious subgeneric boundaries,is one of the most challenging bee groups from a systematic standpoint.An enduring question is the relationship of La-sioglossum and Homalictus,whether all halictine bees with weakened distal wing ve-nation comprise one or multiple genera.Here,we analyzed the phylogenetic relation-ships among the subgroups within Lasioglossum s.l.based on thousands of single-copy orthologs and ultraconserved elements,which were extracted from 23 newly sequenced low-coverage whole genomes alongside a published genome(22 ingroups plus 2 out-groups).Both marker sets provided consistent results across maximum likelihood and coalescent-based species tree approaches.The phylogenetic and topology test results show that the Lasioglossum and Hemihalictus series are reciprocally monophyletic and Homa-lictus and Rostrohalictus are valid subgenera of Lasioglossum.Consequently,we lower Homalictus to subgenus status within Lasioglossum again,and we also raise Rostrohalic-tus to subgenus status from its prior synonymy with subgenus Hemihalictus.Lasioglossum przewalskyi is also transferred to the subgenus Hemihalictus.Ultimately,we redefine La-sioglossum to include all halictine bees with weakened distal wing venation.