A multitaxa assessment of the effectiveness of agri-environmental schemes for biodiversity management.

Agri-environmental schemes (AES) aim to restore biodiversity and biodiversity-mediated ecosystem services in landscapes impoverished by modern agriculture. However, a systematic, empirical evaluation of different AES types across multiple taxa and functional groups is missing. Within one orthogonal design, we studied sown flowering AES types with different temporal continuity, size, and landscape context and used calcareous grasslands as seminatural reference habitat. We measured species richness of 12 taxonomic groups (vascular plants, cicadas, orthopterans, bees, butterflies, moths, hoverflies, flower visiting beetles, parasitoid wasps, carabid beetles, staphylinid beetles, and birds) representing 5 trophic levels. A total of 54,955 specimens were identified using traditional taxonomic methods, and bulk arthropod samples were identified through DNA metabarcoding, resulting in a total of 1,077 and 2,110 taxa, respectively. Species richness of most taxonomic groups, as well as multidiversity and richness of pollinators, increased with temporal continuity of AES types. Some groups responded to size and landscape context, but multidiversity and richness of pollinators and natural enemies were not affected. AES flowering fields supported different species assemblages than calcareous grasslands, but assemblages became more similar to those in seminatural grasslands with increasing temporal continuity. Our results indicate that AES flowering fields and seminatural grasslands function synergistically. Flowering fields support biodiversity even when they are relatively small and in landscapes with few remaining seminatural habitats. We therefore recommend a network of smaller, temporally continuous AES flowering fields of different ages, combined with permanent seminatural grasslands, to maximize benefits for biodiversity conservation and ecosystem service delivery in agricultural landscapes.

Rate variation in the evolution of non-coding DNA associated with social evolution in bees.

The evolutionary origins of eusociality represent increases in complexity from individual to caste-based, group reproduction. These behavioural transitions have been hypothesized to go hand in hand with an increased ability to regulate when and where genes are expressed. Bees have convergently evolved eusociality up to five times, providing a framework to test this hypothesis. To examine potential links between putative gene regulatory elements and social evolution, we compare alignable, non-coding sequences in 11 diverse bee species, encompassing three independent origins of reproductive division of labour and two elaborations of eusocial complexity. We find that rates of evolution in a number of non-coding sequences correlate with key social transitions in bees. Interestingly, while we find little evidence for convergent rate changes associated with independent origins of social behaviour, a number of molecular pathways exhibit convergent rate changes in conjunction with subsequent elaborations of social organization. We also present evidence that many novel non-coding regions may have been recruited alongside the origin of sociality in corbiculate bees; these loci could represent gene regulatory elements associated with division of labour within this group. Thus, our findings are consistent with the hypothesis that gene regulatory innovations are associated with the evolution of eusociality and illustrate how a thorough examination of both coding and non-coding sequence can provide a more complete understanding of the molecular mechanisms underlying behavioural evolution. This article is part of the theme issue 'Convergent evolution in the genomics era: new insights and directions'.

Low-Cost Electronic Tagging System for Bee Monitoring.

This paper introduces both a hardware and a software system designed to allow low-cost electronic monitoring of social insects using RFID tags. Data formats for individual insect identification and their associated experiment are proposed to facilitate data sharing from experiments conducted with this system. The antennas' configuration and their duty cycle ensure a high degree of detection rates. Other advantages and limitations of this system are discussed in detail in the paper.

Coupling of pollination services and coffee suitability under climate change.

Climate change will cause geographic range shifts for pollinators and major crops, with global implications for food security and rural livelihoods. However, little is known about the potential for coupled impacts of climate change on pollinators and crops. Coffee production exemplifies this issue, because large losses in areas suitable for coffee production have been projected due to climate change and because coffee production is dependent on bee pollination. We modeled the potential distributions of coffee and coffee pollinators under current and future climates in Latin America to understand whether future coffee-suitable areas will also be suitable for pollinators. Our results suggest that coffee-suitable areas will be reduced 73-88% by 2050 across warming scenarios, a decline 46-76% greater than estimated by global assessments. Mean bee richness will decline 8-18% within future coffee-suitable areas, but all are predicted to contain at least 5 bee species, and 46-59% of future coffee-suitable areas will contain 10 or more species. In our models, coffee suitability and bee richness each increase (i.e., positive coupling) in 10-22% of future coffee-suitable areas. Diminished coffee suitability and bee richness (i.e., negative coupling), however, occur in 34-51% of other areas. Finally, in 31-33% of the future coffee distribution areas, bee richness decreases and coffee suitability increases. Assessing coupled effects of climate change on crop suitability and pollination can help target appropriate management practices, including forest conservation, shade adjustment, crop rotation, or status quo, in different regions.

Repeated evolution of soldier sub-castes suggests parasitism drives social complexity in stingless bees.

The differentiation of workers into morphological castes represents an important evolutionary innovation that is thought to improve division of labor in insect societies. Given the potential benefits of task-related worker differentiation, it is puzzling that physical worker castes, such as soldiers, are extremely rare in social bees and absent in wasps. Following the recent discovery of soldiers in a stingless bee, we studied the occurrence of worker differentiation in 28 stingless bee species from Brazil and found that several species have specialized soldiers for colony defence. Our results reveal that worker differentiation evolved repeatedly during the last ~ 25 million years and coincided with the emergence of parasitic robber bees, a major threat to many stingless bee species. Furthermore, our data suggest that these robbers are a driving force behind the evolution of worker differentiation as targets of robber bees are four times more likely to have nest guards of increased size than non-targets. These findings reveal unexpected diversity in the social organization of stingless bees.Although common in ants and termites, worker differentiation into physical castes is rare in social bees and unknown in wasps. Here, Grüter and colleagues find a guard caste in ten species of stingless bees and show that the evolution of the guard caste is associated with parasitization by robber bees.

The genomes of two key bumblebee species with primitive eusocial organization.

BACKGROUND: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats. RESULTS: We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits. CONCLUSIONS: These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation.

Preliminary characterization of mitochondrial genome of Melipona scutellaris, a Brazilian stingless bee.

Bees are manufacturers of relevant economical products and have a pollinator role fundamental to ecosystems. Traditionally, studies focused on the genus Melipona have been mostly based on behavioral, and social organization and ecological aspects. Only recently the evolutionary history of this genus has been assessed using molecular markers, including mitochondrial genes. Even though these studies have shed light on the evolutionary history of the Melipona genus, a more accurate picture may emerge when full nuclear and mitochondrial genomes of Melipona species become available. Here we present the assembly, annotation, and characterization of a draft mitochondrial genome of the Brazilian stingless bee Melipona scutellaris using Melipona bicolor as a reference organism. Using Illumina MiSeq data, we achieved the annotation of all protein coding genes, as well as the genes for the two ribosomal subunits (16S and 12S) and transfer RNA genes as well. Using the COI sequence as a DNA barcode, we found that M. cramptoni is the closest species to M. scutellaris.

Prospects of apicultural entrepreneurship in coastal districts of eastern India: a melissopalynological evaluation.

A melissopalynological analysis of fifty-one natural honey samples (twenty four spring, fifteen summer and twelve winter) collected during 2010-2011 from two east-coastal districts (20(0)20/ to 22(0)11/ N, 82(0)39/ to 87(0)01/ E) of Orissa, India was performed. Out of 37 unifloral samples found 25 were contributed by Apis cerana indica, seven by A. dorsata and the remaining five by A. florea. Out of 14 multifloral samples five were contributed by A. cerana indica, five by A. dorsata and the remaining four by A. florea. Principal component analysis confirmed the palynological classification of the unifloral honey samples. Eighty-two bee-plant taxa belonging to forty four families were recovered. The predominant nectariferous taxa of the spring season were Acanthus ilicifolius, Avicennia marina, Bruguiera gymnorrhiza, Cocos nucifera, Eucalyptus globulus, Phoenix paludosa, Pongamia pinnata, Prosopis juliflora, Sonneratia apetala and Syzygium cumini. In the summer the predominant nectariferous taxa were Borassus flabellifer, C. nucifera, E. globulus, Syzygium cumini, Terminalia arjuna, Aegiceras corniculatum, P. paludosa and Sonneratia apetala while those of the winter were Brassica nigra, Coriandrum sativum, Zizyphus jujuba, Alstonia scholaris, E. globulus and Bruguiera gymnorrhiza. Very low (<0.09) HDE/P for 98% of the samples and absence of toxic palynotaxa assure that these honeys are suitable for human consumption. Quite extended honey flow period with spring and summer as best forage seasons for the honeybees and occurrence of 82% of these honeys with APC Group II, III and IV justify the sustainability of the present study area for establishing moderate to large-scale apicultural entrepreneurship. This should improve the socio-economic status of the people of this region.

Assessment of genetic relatedness in the honeybee Apis mellifera L. (Hymenoptera: apidae) colonies by using microsatellite loci.

In this study the relatedness was estimated between mother queen's colony and her daughters' queens' colonies, by extracting DNA from their individual workers offspring (N= 20) and using five microsatellite loci. Locus As indicated more diversity in the length of alleles from 130 to 162 PB with frequency from 0.05 to 0.1, followed by locus A76 that showed alleles lengths 210 to 340 PB with frequency 0.05 to 0.2 that means big diversity in the colonies individuals due to the numbers of drones mated with mother queen. On the other hand, A107 illustrated the weight of alleles from 179 to 205 PB with frequency 0.05 to 0.25. Loci B124 and ACOO6 also showed high frequency of 0.25 and indicated more relatedness. Through locus 8124 the Correlation coefficient was 1.00 between P.Q and F,.QO and 0.87 for P.Q and F1.Q1 and F,.Q3. A43 indicated relatedness through the correlation coefficient (0.968) between F.Q1.and F2.Q2. The microsatellites demonstrated that there was a genetic diversity within and between colonies.

Phylogenetic position of the endemic large carpenter bee of the Ogasawara Islands, Xylocopa ogasawarensis (Matsumura, 1912) (Hymenoptera: Apidae), inferred from four genes.

The Ogasawara (Bonin) Islands are oceanic islands of volcanic origin located in the northwestern Pacific Ocean about 1,000 km south of the Japanese mainland. A large carpenter bee, Xylocopa (Koptortosoma) ogasawarensis, is endemic to the islands but its closest relative is unknown. The Ogasawara Islands are geographically closest to the Japanese Archipelago, but this area is inhabited only by species of a different subgenus, Alloxylocopa. Thus, X. ogasawarensis is commonly thought to have originated from other members of Koptortosoma, which is widely distributed in the Oriental tropical region. In this study, we investigated the origin of X. ogasawarensis using a phylogenetic analysis of Xylocopa based on four genes: mitochondrial cytochrome oxidase subunit I (COI) and cytochrome b (Cyt b), and nuclear elongation factor-1alpha (EF-1alpha) and phosphoenolpyruvate carboxykinase (PEPCK). A combined analysis of the four genes strongly suggests that Koptortosoma is a large, polyphyletic group, within which Alloxylocopa is embedded. Xylocopa ogasawarensis emerged as the species most closely related to Alloxylocopa and not to Oriental species of Koptortosoma. Contrary to previous views of the origin of X. ogasawarensis, our results suggest that X. ogasawarensis and Alloxylocopa share a common origin and diverged after they colonized the island regions of East Asia.

Redundant species, cryptic host-associated divergence, and secondary shift in Sennertia mites (Acari: Chaetodactylidae) associated with four large carpenter bees (Hymenoptera: Apidae: Xylocopa) in the Japanese island arc.

Sennertia mites live as inquilines in the nests of carpenter bees and disperse as deutonymphs on newly emerged adult bees. Because their life cycle is tightly linked to that of the host bees, Sennertia may diverge in response to speciation in the hosts. However, the majority of Sennertia species are associated with several closely related carpenter bees, suggesting that host speciation may not be reflected in mite genetic structure. Here we investigate the extent of host-associated genetic differentiation in two Sennertia mites (S. alfkeni and S. japonica) that share four closely related, strictly allopatric large carpenter bees (Xylocopa). Analysis of the mitochondrial cytochrome oxidase subunit I (COI) gene in Sennertia unexpectedly indicates that the two species represent morphological variants of a single species, and they collectively group into four distinct, allopatric clades that are uniquely associated with a single Xylocopa host. An exception is the mites associated with X. amamensis of the northernmost populations, which have genotypes typical of those associated with neighboring X. appendiculatacircumvolans. Additional analysis using amplified fragment length polymorphism (AFLP) further corroborates the presence of four mite clades but contrary to the COI data, suggests that the mites of the southernmost population of X. appendiculatacircumvolans have genetic profiles typical of those associated with X. amamensis. These results indicate that some mites have undergone secondary host switch after the formation of the four mite lineages and further experienced mitochondrial introgression during period of lineage coexistence. Overall, our results strongly urge reappraisal of deutonymph-based mite taxonomy and illuminate the importance of host-associated divergence during incipient stage of speciation in chaetodactylid mites. Furthermore, the occurrence of host switch and introgression between genetically differentiated mites entails that two host species have co-occurred in the past, thus providing a unique source of evidence for migration and competitive exclusion between the presently allopatric Xylocopa hosts.

Phylogeny and biogeography of bees of the tribe Osmiini (Hymenoptera: Megachilidae).

The Osmiini (Megachilidae) constitute a taxonomically and biologically diverse tribe of bees. To resolve their generic and suprageneric relationships, we inferred a phylogeny based on three nuclear genes (Elongation factor 1-alpha, LW-rhodopsin and CAD) applying both parsimony and Bayesian methods. Our phylogeny, which includes 95 osmiine species representing 18 of the 19 currently recognized genera, is well resolved with high support for most basal nodes. The core osmiine genera were found to form a well-supported monophyletic group, but four small genera, Noteriades, Afroheriades,Pseudoheriades and possibly Ochreriades, formerly included in the Osmiini, do not appear to belong within this tribe. Our phylogeny results in the following taxonomic changes: Stenosmia and Hoplosmia are reduced to subgeneric rank in Hoplitis and Osmia, respectively, Micreriades is recognized as a subgenus in Hoplitis and the subgenus Nasutosmia is transferred from Hoplitis to Osmia. We inferred a biogeographic scenario for the Osmiini applying maximum likelihood inference and models of character evolution. We provide evidence that the Osmiini originated in the Palearctic, and that extensive exchanges occurred between the Palearctic and the Nearctic. The latter finding may relate to the fact that many osmiine species nest in wood or in stems, facilitating dispersal by overseas transport of the nests.

Molecular phylogenetics of the exoneurine allodapine bees reveal an ancient and puzzling dispersal from Africa to Australia.

Previous phylogenetic studies of the bee tribe Allodapini suggested a puzzling biogeographic problem: one of the key basal divergences involved separation of the southern African and southern Australian clades at a very early stage in allodapine evolution, but no taxa occur in the Palaearctic or Asian regions that might suggest a Laurasian dispersal route. However, these studies lacked sufficient sequence data and appropriate maximum likelihood partition models to provide reliable phylogenetic estimates and enable alternative biogeographic hypotheses to be distinguished. Using Bayesian and penalized likelihood approaches and an expanded sequence and taxon set we examine phylogenetic relationships between the Australian, African, and Malagasy groups and estimate divergence times for key nodes. We show that divergence of the three basal Australian clades (known as the exoneurines) occurred at least 25 Mya following a single colonization event, and that this group diverged from the African + Madagascan clade at least 30 Mya, but actual divergence dates are likely to be much older than these very conservative limits. The bifurcation order of the exoneurine clades was not resolved and analyses could not rule out the existence of a hard polytomy, suggesting rapid radiation after colonization of Australia. Their divergence involved major transitions in life history traits and these placed constraints on the kinds of social organization that subsequently evolved in each lineage. Early divergence between the African, Malagasy, and Australian clades presents a major puzzle for historical biogeography: node ages are too recent for Gondwanan vicariance hypotheses, but too early for Laurasian dispersal scenarios. We suggest a scenario involving island hopping across the Indian Ocean via a series of now largely submerged elements of the Kergulen Plateau and Broken Ridge provinces, both of which are known to have had subaerial formations during the Cenozoic. [Bayesian; biogeography; dispersal; Gondwana; Kerguelen Plateau; penalized likelihood.].