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Abstract Many insect groups have acquired obligate microbial symbionts, and the resulting associations can have important ecological and evolutionary consequences. A notable example among ants is the species‐rich tribe Camponotini, whose members derive nutritional benefits from a vertically inherited bacterial endosymbiont,Blochmannia. We generate ultraconserved element (UCE) phylogenomic data for 220 ingroup and 5 outgroup taxa to reconstruct a detailed evolutionary history of the Camponotini, including the inference of divergence times and dispersal events. Under multiple modes of analysis, including both concatenation and species‐tree approaches, we recover a well‐supported backbone phylogeny comprising eight lineages: three large genera (Camponotus,Colobopsis,Polyrhachis) and several smaller genera or clusters of genera. Three novel lineages are uncovered that cannot be placed in any existing genus:Lathidrisgen. n., from the mountains of Mesoamerica;Retalimyrmagen. n., from the Indian Himalayas; andUwarigen. n., from eastern Asia. The species in these new genera were described and placed erroneously inCamponotus. The tribe Camponotini is estimated to have a crown origin in the Eocene (median age 38.4 Ma), with successively younger crown ages forColobopsis(22.5 Ma),Camponotus(18.6 Ma) andPolyrhachis(18.5 Ma). We infer an Australasian or Indomalayan origin for the tribe, with multiple dispersal events to the Afrotropics, Palearctic region, and New World. Phylogenetic analysis of selectedBlochmanniagenes from a subset of 97 camponotine taxa yields results that are largely congruent with the ant host phylogeny, at least for well‐supported nodes, but we find evidence thatBlochmanniafrom some old lineages—especiallyLathidris—may have discordant histories, suggesting possible lability of this symbiosis in the early evolution of camponotine ants. 

Abstract Most canopy insect research takes place in tropical forests, where communities are highly vertically stratified. However, temperate forest canopies also provide critical resources to many species and are under intense pressure from global change drivers. The relative lack of knowledge regarding temperate canopy insect ecology impedes our forest management and conservation decisions such that we may be losing temperate canopy biodiversity before we know it exists.We directly compared ant diversity and community composition on the ground and in the tree canopy of North American temperate deciduous forests for the first time. We also evaluated two canopy sampling methods—baits and hand collections.We collected 34 ant species from 102 trees across seven sites. Ant diversity was greater on the ground than in the canopy, and species turnover created distinct communities across vertical strata. Only 12% of species were exclusively arboreal, but 47% were collected in both strata, indicating the canopy is an important resource for temperate ants, even if they are not restricted there.Baiting and hand‐collecting recovered similar species richness, but whether baits captured a subset of hand‐collected species or a unique assemblage was site‐dependent. Nevertheless, we suggest that these methods are most effective in conjunction.Hand collection allowed us to document arboreal nests of 10 species, including the invasive needle ant,Brachyponera chinensis, which was previously thought to be strictly terrestrial.Our results emphasise the importance of including the canopy in temperate forest ecology and conservation assessments. 

Abstract The order Hymenoptera (wasps, ants, sawflies, and bees) represents one of the most diverse animal lineages, but whether specific key innovations have contributed to its diversification is still unknown. We assembled the largest time-calibrated phylogeny of Hymenoptera to date and investigated the origin and possible correlation of particular morphological and behavioral innovations with diversification in the order: the wasp waist of Apocrita; the stinger of Aculeata; parasitoidism, a specialized form of carnivory; and secondary phytophagy, a reversal to plant-feeding. Here, we show that parasitoidism has been the dominant strategy since the Late Triassic in Hymenoptera, but was not an immediate driver of diversification. Instead, transitions to secondary phytophagy (from parasitoidism) had a major influence on diversification rate in Hymenoptera. Support for the stinger and the wasp waist as key innovations remains equivocal, but these traits may have laid the anatomical and behavioral foundations for adaptations more directly associated with diversification. 

The delineation of zoogeographic regions is essential for understanding the evolution of biodiversity. Madagascar, characterized by high levels of endemism and habitat diversity, presents unique challenges and opportunities for such studies. Traditional global zoogeographic classifications, largely based on vertebrates, may overlook finer‐scale patterns of diversity. This study employs comprehensive ant distribution and phylogenomic datasets to propose a refined zoogeographic model for Madagascar. Utilizing phylogenetic Simpson's turnover, we identified three primary regions – Eastern, Northern, and Western – each characterized by distinct environmental and phylogenetic profiles. Further subdivision revealed nine subregions, reflecting variations in elevation, net primary productivity, and terrain ruggedness. Our findings highlight the importance of topographical and environmental barriers in shaping phylogenetic diversity and endemism. Notably, we observed significant phylogenetic clustering in lowland areas and distinct differences in net primary productivity and elevation across regions. This study underscores the value of integrating phylogenetic data in zoogeographic analyses and provides a nuanced framework for investigating biodiversity patterns in Madagascar, offering insights into the processes driving speciation and endemism on the island.