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Bumble bees exhibit body size clines across an urban gradient despite low genetic differentiation. Sci Rep 2022; 12:4166. [PMID: 35264687 PMCID: PMC8907314 DOI: 10.1038/s41598-022-08093-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 02/28/2022] [Indexed: 11/23/2022] Open
Abstract
Environmental heterogeneity resulting from human-modified landscapes can increase intraspecific trait variation. However, less known is whether such phenotypic variation is driven by plastic or adaptive responses to local environments. Here, we study five bumble bee (Apidae: Bombus) species across an urban gradient in the greater Saint Louis, Missouri region in the North American Midwest and ask: (1) Can urban environments induce intraspecific spatial structuring of body size, an ecologically consequential functional trait? And, if so, (2) is this body size structure the result of plasticity or adaptation? We additionally estimate genetic diversity, inbreeding, and colony density of these species—three factors that affect extinction risk. Using ≥ 10 polymorphic microsatellite loci per species and measurements of body size, we find that two of these species (Bombus impatiens, Bombus pensylvanicus) exhibit body size clines across the urban gradient, despite a lack of population genetic structure. We also reaffirm reports of low genetic diversity in B. pensylvanicus and find evidence that Bombus griseocollis, a species thought to be thriving in North America, is inbred in the greater Saint Louis region. Collectively, our results have implications for conservation in urban environments and suggest that plasticity can cause phenotypic clines across human-modified landscapes.
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2
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Conflitti IM, Arshad Imrit M, Morrison B, Sharma S, Colla SR, Zayed A. Bees in the six: Determinants of bumblebee habitat quality in urban landscapes. Ecol Evol 2022; 12:e8667. [PMID: 35356573 PMCID: PMC8935973 DOI: 10.1002/ece3.8667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 02/03/2022] [Accepted: 02/07/2022] [Indexed: 12/02/2022] Open
Abstract
With growing urbanization, it is becoming increasingly important to design cities in a manner that sustains and enhances biodiversity and ecosystem services. Native bees are critical pollinators that have experienced substantive declines over the past several decades. These declines have captured the attention of the public, particularly urbanites, prompting a large interest in protecting pollinators and their habitats in cities across North America and Europe. Unfortunately, we currently lack research about specific features of urban environments that can enhance the fitness of pollinators. We carried out an intensive study of Bombus impatiens, the Common Eastern Bumblebee, in the city of Toronto (Canada's largest city), to better understand landscape parameters that provide high-quality habitat for this species and likely other generalist bees. We divided the city into 270 grid cells and sampled a large number of worker bees, which were then genotyped at twelve hypervariable microsatellite loci. The genetic data allowed us to quantify the effective number of colonies and foraging distance for bumblebees in our study area. We then asked how the city's landscape and human population demography and income are associated with the availability of high-quality habitat for B. impatiens. Several aspects of Toronto's landscape influenced colony density and foraging range. Urbanization had a clear effect on both colony density and foraging distance of workers. On the other hand, functional (i.e., not cosmetic) green space was often associated with higher quality habitats for bumblebees. Our study suggests several planning strategies to enhance habitat quality for bumblebees and other pollinators in cities.
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Affiliation(s)
| | | | | | - Sapna Sharma
- Department of BiologyYork UniversityTorontoOntarioCanada
| | - Sheila R. Colla
- Faculty of Environmental & Urban ChangeYork UniversityTorontoOntarioCanada
| | - Amro Zayed
- Department of BiologyYork UniversityTorontoOntarioCanada
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3
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Butler RG, Lage C, Dobrin SE, Staples JK, Venturini E, Frank J, Drummond FA. Maine's Bumble Bees (Hymenoptera: Apidae)-Part 2: Comparisons of a Common (Bombus ternarius) and a Rare (Bombus terricola) Species. ENVIRONMENTAL ENTOMOLOGY 2021; 50:1358-1369. [PMID: 34532731 DOI: 10.1093/ee/nvab100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Indexed: 06/13/2023]
Abstract
As part of a quantitative survey of Maine's bumble bee fauna (Butler et al. 2021), we compared and contrasted genetic diversity, parasite and pathogen burdens, and pesticide exposure of the relatively common Bombus ternarius Say, 1937 and the spatially rare Bombus terricola Kirby, 1837. We recorded 11 Bombus species at 40 survey sites across three Maine ecoregions, and B. ternarius was the most common species, while B. terricola was spatially rare. Nonmetric multidimensional scaling indicated that B. terricola was associated with higher elevation sites in Maine, while B. ternarius was more broadly distributed in the state. Pollinator networks constructed for each bee indicated B. ternarius foraged on more plant species than B. terricola, but that there was considerable overlap (73%) in plant species visited. Genetic diversity was greater in the spatially restricted B. terricola, whereas the widely distributed B. ternarius was characterized by greater genetic differentiation among regions. Bombus terricola had higher molecular marker levels of the microsporidian fungi Nosema spp. and the trypanosome Crithidia spp., and both species had high levels of Trypanosoma spp. exposure. No Western Honey Bee (Apis mellifera, Linnaeus, 1758) viruses were detected in either species. Pesticides were not detected in pollen samples collected from workers of either species, and B. ternarius worker tissue samples exhibited only trace levels of diflubenzuron.
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Affiliation(s)
- Ronald G Butler
- Department of Biology, University of Maine, Farmington, ME, USA
| | - Christopher Lage
- College of Arts and Sciences, University of Maine Augusta, Augusta, ME, USA
| | - Scott E Dobrin
- Collegium of Natural Sciences, Eckerd College, St. Petersburg, FL, USA
| | - Joseph K Staples
- Department of Environmental Science and Policy, University of Southern Maine, Gorham, ME, USA
| | - Eric Venturini
- Maine Wild Blueberry Commission, University of Maine, Orono, ME, USA
| | - Jereme Frank
- Maine Forest Service, Department of Agriculture Conservation and Forestry, Old Town, ME, USA
| | - Francis A Drummond
- Professor Emeritus, School of Biology and Ecology, University of Maine, Orono, ME, USA
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4
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Watrous KM, Costa CP, Diaz YR, Woodard SH. Flexibility in the Critical Period of Nutrient Sequestration in Bumble Bee Queens. Integr Org Biol 2021; 3:obab009. [PMID: 34104874 PMCID: PMC8179628 DOI: 10.1093/iob/obab009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Synopsis Bumble bee queens undergo a nutrient storage period prior to entering diapause wherein they sequester glycogen and lipids that are metabolized during overwintering. In the laboratory under optimal food availability conditions, the majority of nutrients are sequestered during the first few days of adulthood. However, if food resources are scarce during this narrow window of time, wild queen bumble bees might be limited in their ability to obtain adequate food resources for overwintering. Here we used a laboratory experiment to examine whether queen bumble bees exhibit flexibility in the timing of pre-overwintering nutrient sequestration, by limiting their access to either nectar (artificial) or pollen, the two primary foods for bumble bees, for varying periods of time. In response to these treatments, we quantified queen survival, changes in weight, and glycogen and lipids levels. We found evidence that queens are able to recuperate almost entirely from food resource limitation, with respect to nutrient storage, especially when it is experienced for shorter durations (up to 6 days). This study sheds light on how bumble bee queens are impacted by food resource availability at a critical life stage. Portuguese As abelhas rainhas do gênero Bombus armazenam nutrientes antes de entrarem em diapausa, sequestrando o glicogênio e os lipídios que serão metabolizados durante o inverno. Em condições ideais de disponibilidade de alimento no laboratório, a maioria dos nutrientes é sequestrada nos primeiros dias de vida adulta. No entanto, em condições de escassez de alimento na natureza, as rainhas podem sofrer limitações em sua capacidade de obter recursos para o inverno. Nesse contexto, em condições controladas, examinamos se as rainhas exibem variações no sequestro de nutrientes, limitando o acesso ao néctar (artificial) ou pólen, seus principais alimentos, em diferentes intervalos de tempo. Em resposta a esses tratamentos, quantificamos a taxa de sobrevivência das rainhas, as mudanças no peso e os níveis de glicogênio e lipídios. Encontramos evidências de que as rainhas são capazes de recuperar a capacidade de armazenar nutrientes quase inteiramente, especialmente em períodos mais curtos de escassez de alimento (até 6 dias). Este estudo lança luz sobre como as rainhas são afetadas pela variação na disponibilidade de recursos alimentares em um estágio crítico da vida. Spanish Las abejas reinas de generó Bombus, mejor conocidas como reinas de abejorro se someten a un período de almacenamiento de nutrientes antes de entrar en diapausa, en el cual secuestran glucógeno y lípidos que se metabolizan durante el invierno. En el laboratorio, en condiciones óptimas de disponibilidad de alimentos, la mayoría de los nutrientes se secuestran durante los primeros días de la edad adulta. Sin embargo, si los recursos alimenticios son escasos durante esta estrecha ventana de tiempo, las abejas reinas silvestres podrían verse limitadas en su capacidad para obtener recursos alimenticios adecuados para pasar el invierno. Aquí utilizamos un experimento de laboratorio para examinar si las abejas reinas exhiben flexibilidad en el momento del secuestro de nutrientes antes de la hibernación, al limitar su acceso al néctar (artificial) o al polen, los dos alimentos principales de los abejorros, durante períodos variables. En respuesta a estos tratamientos, cuantificamos la supervivencia de la reina, los cambios de peso y los niveles de glucógeno y lípidos. Encontramos evidencia de que las reinas pueden recuperarse casi por completo de la limitación de los recursos alimenticios, con respecto al almacenamiento de nutrientes, especialmente cuando se experimenta por períodos más cortos (hasta 6 días). Este estudio arroja luz sobre cómo las abejas reinas se ven afectadas por la disponibilidad de recursos alimenticios en una etapa crítica de la vida.
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Affiliation(s)
- Kristal M Watrous
- Department of Entomology, The University of California, Riverside, CA 92521, USA
| | - Claudinéia P Costa
- Department of Entomology, The University of California, Riverside, CA 92521, USA
| | - Yadira R Diaz
- Department of Entomology, The University of California, Riverside, CA 92521, USA
| | - S Hollis Woodard
- Department of Entomology, The University of California, Riverside, CA 92521, USA
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5
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Ballare KM, Jha S. Genetic structure across urban and agricultural landscapes reveals evidence of resource specialization and philopatry in the Eastern carpenter bee, Xylocopa virginica L. Evol Appl 2021; 14:136-149. [PMID: 33519961 PMCID: PMC7819568 DOI: 10.1111/eva.13078] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 05/27/2020] [Accepted: 07/06/2020] [Indexed: 01/03/2023] Open
Abstract
Human activity continues to impact global ecosystems, often by altering the habitat suitability, persistence, and movement of native species. It is thus critical to examine the population genetic structure of key ecosystemservice providers across human-altered landscapes to provide insight into the forces that limit wildlife persistence and movement across multiple spatial scales. While some studies have documented declines of bee pollinators as a result of human-mediated habitat alteration, others suggest that some bee species may benefit from altered land use due to increased food or nesting resource availability; however, detailed population and dispersal studies have been lacking. We investigated the population genetic structure of the Eastern carpenter bee, Xylocopa virginica, across 14 sites spanning more than 450 km, including dense urban areas and intensive agricultural habitat. X. virginica is a large bee which constructs nests in natural and human-associated wooden substrates, and is hypothesized to disperse broadly across urbanizing areas. Using 10 microsatellite loci, we detected significant genetic isolation by geographic distance and significant isolation by land use, where urban and cultivated landscapes were most conducive to gene flow. This is one of the first population genetic analyses to provide evidence of enhanced insect dispersal in human-altered areas as compared to semi-natural landscapes. We found moderate levels of regional-scale population structure across the study system (G'ST = 0.146) and substantial co-ancestry between the sampling regions, where co-ancestry patterns align with major human transportation corridors, suggesting that human-mediated movement may be influencing regional dispersal processes. Additionally, we found a signature of strong site-level philopatry where our analyses revealed significant levels of high genetic relatedness at very fine scales (<1 km), surprising given X. virginica's large body size. These results provide unique genetic evidence that insects can simultaneously exhibit substantial regional dispersal as well as high local nesting fidelity in landscapes dominated by human activity.
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Affiliation(s)
- Kimberly M. Ballare
- Department of Integrative BiologyBiological LaboratoriesThe University of Texas at AustinAustinTXUSA
- Department of Ecology and Evolutionary BiologyUniversity of California Santa CruzSanta CruzCAUSA
| | - Shalene Jha
- Department of Integrative BiologyBiological LaboratoriesThe University of Texas at AustinAustinTXUSA
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6
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Chan KMA, Satterfield T. The maturation of ecosystem services: Social and policy research expands, but whither biophysically informed valuation? PEOPLE AND NATURE 2020. [DOI: 10.1002/pan3.10137] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Affiliation(s)
- Kai M. A. Chan
- Institute of Resources, Environment and Sustainability The University of British Columbia Vancouver BC Canada
| | - Terre Satterfield
- Institute of Resources, Environment and Sustainability The University of British Columbia Vancouver BC Canada
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7
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Abstract
Bumble bees (Bombus) are unusually important pollinators, with approximately 260 wild species native to all biogeographic regions except sub-Saharan Africa, Australia, and New Zealand. As they are vitally important in natural ecosystems and to agricultural food production globally, the increase in reports of declining distribution and abundance over the past decade has led to an explosion of interest in bumble bee population decline. We summarize data on the threat status of wild bumble bee species across biogeographic regions, underscoring regions lacking assessment data. Focusing on data-rich studies, we also synthesize recent research on potential causes of population declines. There is evidence that habitat loss, changing climate, pathogen transmission, invasion of nonnative species, and pesticides, operating individually and in combination, negatively impact bumble bee health, and that effects may depend on species and locality. We distinguish between correlational and causal results, underscoring the importance of expanding experimental research beyond the study of two commercially available species to identify causal factors affecting the diversity of wild species.
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Affiliation(s)
- Sydney A Cameron
- Department of Entomology, University of Illinois, Urbana, Illinois 61801, USA;
| | - Ben M Sadd
- School of Biological Sciences, Illinois State University, Normal, Illinois 61790, USA;
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8
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Maebe K, Karise R, Meeus I, Mänd M, Smagghe G. Level of Genetic Diversity in European Bumblebees is Not Determined by Local Species Abundance. Front Genet 2019; 10:1262. [PMID: 31921301 PMCID: PMC6914865 DOI: 10.3389/fgene.2019.01262] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 11/15/2019] [Indexed: 11/25/2022] Open
Abstract
Bumblebee species with declining population trends tend to show lower genetic diversity levels than stable species. The observed difference might be explained by abundance differences, with declining bumblebee species having lower genetic diversity levels simply due to their lower local species abundances. However, whether this holds true is not known. Here, we investigated whether bumblebee local abundances determines population genetic diversity levels. Therefore, local species abundances were measured for bumblebee species at four locations in Belgium and two locations in Estonia during bumblebee foraging years 2013–2017. These locations and countries were chosen to ensure the greatest possible variance in both local abundances and population trends for these species. Hence, genetic diversity levels were obtained for seven species by genotyping collected specimens with 16 microsatellites. Our results showed that the observed patterns in genetic diversity did not depend on local species abundance. So, although declining bumblebee species can become locally abundant, they will still show lower genetic diversity levels than stable species. This result implies that measuring bumblebees’ local abundance cannot be used to directly determine the health status of a population. Furthermore, this result has also major impact on future conservation strategies as increasing the genetic diversity levels of declining species will be very difficult, and habitat quality should be high to maintain their populations, otherwise these species are doomed to disappear first.
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Affiliation(s)
- Kevin Maebe
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Reet Karise
- Institute of Agricultural and Environmental Sciences, University of Life Sciences, Tartu, Estonia
| | - Ivan Meeus
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Marika Mänd
- Institute of Agricultural and Environmental Sciences, University of Life Sciences, Tartu, Estonia
| | - Guy Smagghe
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
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9
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Pattern of population structuring between Belgian and Estonian bumblebees. Sci Rep 2019; 9:9651. [PMID: 31273269 PMCID: PMC6609714 DOI: 10.1038/s41598-019-46188-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 06/24/2019] [Indexed: 11/23/2022] Open
Abstract
Several population genetic studies investigated the extent of gene flow and population connectivity in bumblebees. In general, no restriction in gene flow is considered for mainland populations of common bumblebee species. Whether this assumption holds true for all species is not known. An assessment of bumblebee genetic structure in the context of their geographic distribution is needed to prioritize conservation and management needs. Here, we conducted a genetic study on seven bumblebee species occurring in Belgium and Estonia. Using 16 microsatellite markers, we investigated genetic diversity and population structuring in each species. This is the first study investigating population structuring of both declining and stable bumblebee species on both small and large geographic scales. Our results showed no or only low population structuring between the populations of the restricted and declining bumblebee species on both scales, while significant structuring was found for populations of the common species on the larger scale. The latter result, which may be due to human or environmental changes in the landscape, implies the need for the conservation of also widespread bumblebee species. Conservation strategies to improve gene flow and connectivity of populations could avoid the isolation and future losses of populations of these important species.
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10
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Crowther LP, Wright DJ, Richardson DS, Carvell C, Bourke AFG. Spatial ecology of a range-expanding bumble bee pollinator. Ecol Evol 2019; 9:986-997. [PMID: 30805135 PMCID: PMC6374649 DOI: 10.1002/ece3.4722] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 09/20/2018] [Accepted: 10/11/2018] [Indexed: 01/16/2023] Open
Abstract
Molecular methods have greatly increased our understanding of the previously cryptic spatial ecology of bumble bees (Bombus spp.), with knowledge of the spatial ecology of these bees being central to conserving their essential pollination services. Bombus hypnorum, the Tree Bumble Bee, is unusual in that it has recently rapidly expanded its range, having colonized much of the UK mainland since 2001. However, the spatial ecology of B. hypnorum has not previously been investigated. To address this issue, and to investigate whether specific features of the spatial ecology of B. hypnorum are associated with its rapid range expansion, we used 14 microsatellite markers to estimate worker foraging distance, nest density, between-year lineage survival rate and isolation by distance in a representative UK B. hypnorum population. After assigning workers to colonies based on full or half sibship, we estimated the mean colony-specific worker foraging distance as 103.6 m, considerably less than values reported from most other bumble bee populations. Estimated nest density was notably high (2.56 and 0.72 colonies ha-1 in 2014 and 2015, respectively), estimated between-year lineage survival rate was 0.07, and there was no evidence of fine-scale isolation by distance. In addition, genotyping stored sperm dissected from sampled queens confirmed polyandry in this population (mean minimum mating frequency of 1.7 males per queen). Overall, our findings establish critical spatial ecological parameters and the mating system of this unusual bumble bee population and suggest that short worker foraging distances and high nest densities are associated with its rapid range expansion.
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Affiliation(s)
- Liam P. Crowther
- School of Environmental SciencesUniversity of East Anglia, Norwich Research ParkNorwichUK
| | - David J. Wright
- School of Biological SciencesUniversity of East Anglia, Norwich Research Park NorwichUK
| | - David S. Richardson
- School of Biological SciencesUniversity of East Anglia, Norwich Research Park NorwichUK
| | - Claire Carvell
- NERC Centre for Ecology & HydrologyCrowmarsh GiffordWallingfordUK
| | - Andrew F. G. Bourke
- School of Biological SciencesUniversity of East Anglia, Norwich Research Park NorwichUK
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11
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Monitoring of the Apple Fruit Moth: Detection of Genetic Variation and Structure Applying a Novel Multiplex Set of 19 STR Markers. Molecules 2018; 23:molecules23040850. [PMID: 29642498 PMCID: PMC6017289 DOI: 10.3390/molecules23040850] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 04/03/2018] [Accepted: 04/05/2018] [Indexed: 11/29/2022] Open
Abstract
The apple fruit moth Argyresthia conjugella (Lepidoptera, Yponomeutidae) is a seed predator of rowan (Sorbus aucuparia) and is distributed in Europe and Asia. In Fennoscandia (Finland, Norway and Sweden), rowan fruit production is low every 2–4 years, and apple (Malus domestica) functions as an alternative host, resulting in economic loss in apple crops in inter-mast years. We have used Illumina MiSeq sequencing to identify a set of 19 novel tetra-nucleotide short tandem repeats (STRs) in Argyresthia conjugella. Such motifs are recommended for genetic monitoring, which may help to determine the eco-evolutionary processes acting on this pest insect. The 19 STRs were optimized and amplified into five multiplex PCR reactions. We tested individuals collected from Norway and Sweden (n = 64), and detected very high genetic variation (average 13.6 alleles, He = 0.75) compared to most other Lepidoptera species studied so far. Spatial genetic differentiation was low and gene flow was high in the test populations, although two non-spatial clusters could be detected. We conclude that this set of genetic markers may be a useful resource for population genetic monitoring of this economical important insect species.
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12
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Fountain T, Husby A, Nonaka E, DiLeo MF, Korhonen JH, Rastas P, Schulz T, Saastamoinen M, Hanski I. Inferring dispersal across a fragmented landscape using reconstructed families in the Glanville fritillary butterfly. Evol Appl 2017. [DOI: 10.1111/eva.12552] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
- Toby Fountain
- Department of Biosciences; University of Helsinki; Helsinki Finland
- Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - Arild Husby
- Department of Biosciences; University of Helsinki; Helsinki Finland
| | - Etsuko Nonaka
- Department of Biosciences; University of Helsinki; Helsinki Finland
- Department of Biology; Lund University; Lund Sweden
| | | | - Janne H. Korhonen
- Department of Biosciences; University of Helsinki; Helsinki Finland
- Department of Computer Science; Aalto University; Aalto Finland
| | - Pasi Rastas
- Department of Biosciences; University of Helsinki; Helsinki Finland
- Department of Zoology; University of Cambridge; Cambridge UK
| | - Torsti Schulz
- Department of Biosciences; University of Helsinki; Helsinki Finland
| | | | - Ilkka Hanski
- Department of Biosciences; University of Helsinki; Helsinki Finland
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13
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A century of temporal stability of genetic diversity in wild bumblebees. Sci Rep 2016; 6:38289. [PMID: 27917908 PMCID: PMC5137105 DOI: 10.1038/srep38289] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 11/07/2016] [Indexed: 11/23/2022] Open
Abstract
Since the 1950s, bumblebee (Bombus) species are showing a clear decline worldwide. Although many plausible drivers have been hypothesized, the cause(s) of this phenomenon remain debated. Here, genetic diversity in recent versus historical populations of bumblebee species was investigated by selecting four currently restricted and four currently widespread species. Specimens from five locations in Belgium were genotyped at 16 microsatellite loci, comparing historical specimens (1913–1915) with recent ones (2013–2015). Surprisingly, our results showed temporal stability of genetic diversity in the restricted species. Furthermore, both historical and recent populations of restricted species showed a significantly lower genetic diversity than found in populations of co-occurring widespread species. The difference in genetic diversity between species was thus already present before the alleged recent drivers of bumblebee decline could have acted (from the 1950’s). These results suggest that the alleged drivers are not directly linked with the genetic variation of currently declining bumblebee populations. A future sampling in the entire distribution range of these species will infer if the observed link between low genetic diversity and population distribution on the Belgium scale correlates with species decline on a global scale.
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14
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Population genetics and geometric morphometrics of the Bombus ephippiatus species complex with implications for its use as a commercial pollinator. CONSERV GENET 2016. [DOI: 10.1007/s10592-016-0903-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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15
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Couchoux C, Seppä P, van Nouhuys S. Strong dispersal in a parasitoid wasp overwhelms habitat fragmentation and host population dynamics. Mol Ecol 2016; 25:3344-55. [DOI: 10.1111/mec.13696] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 04/14/2016] [Accepted: 05/02/2016] [Indexed: 01/22/2023]
Affiliation(s)
- C. Couchoux
- Department of Biosciences; Metapopulation Research Centre; University of Helsinki; PO Box 65 Helsinki FI-00014 Finland
| | - P. Seppä
- Department of Biosciences; Centre of Excellence in Biological Interactions; University of Helsinki; PO Box 65 Helsinki FI-00014 Finland
| | - S. van Nouhuys
- Department of Biosciences; Metapopulation Research Centre; University of Helsinki; PO Box 65 Helsinki FI-00014 Finland
- Department of Ecology and Evolutionary Biology; Cornell University; Ithaca NY 14853 USA
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16
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Bartlett M, Hale R, Hale M. Habitat quality limits gene flow between populations of Bombus ruderatus in the South Island, New Zealand. CONSERV GENET 2016. [DOI: 10.1007/s10592-016-0816-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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17
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Redhead JW, Dreier S, Bourke AFG, Heard MS, Jordan WC, Sumner S, Wang J, Carvell C. Effects of habitat composition and landscape structure on worker foraging distances of five bumble bee species. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2016; 26:726-739. [PMID: 27411246 DOI: 10.1890/15-0546] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Bumble bees (Bombus spp.) are important pollinators of both crops and wildflowers. Their contribution to this essential ecosystem service has been threatened over recent decades by changes in land use, which have led to declines in their populations. In order to design effective conservation measures, it is important to understand the effects of variation in landscape composition and structure on the foraging activities of worker bumble bees. This is because the viability of individual colonies is likely to be affected by the trade-off between the energetic costs of foraging over greater distances and the potential gains from access to additional resources. We used field surveys, molecular genetics, and fine resolution remote sensing to estimate the locations of wild bumble bee nests and to infer foraging distances across a 20-km² agricultural landscape in southern England, UK. We investigated five species, including the rare B. ruderatus and ecologically similar but widespread B. hortorum. We compared worker foraging distances between species and examined how variation in landscape composition and structure affected foraging distances at the colony level. Mean worker foraging distances differed significantly between species. Bombus terrestris, B. lapidarius, and B. ruderatus exhibited significantly greater mean foraging distances (551, 536, and 501 m, respectively) than B. hortorum and B. pascuorum (336 and 272 m, respectively). There was wide variation in worker foraging distances between colonies of the same species, which was in turn strongly influenced by the amount and spatial configuration of available foraging habitats. Shorter foraging distances were found for colonies where the local landscape had high coverage and low fragmentation of semi-natural vegetation, including managed agri-environmental field margins. The strength of relationships between different landscape variables and foraging distance varied between species, for example the strongest relationship for B. ruderatus being with floral cover of preferred forage plants. Our findings suggest that management of landscape composition and configuration has the potential to reduce foraging distances across a range of bumble bee species. There is thus potential for improvements in the design and implementation of landscape management options, such as agri-environment schemes, aimed at providing foraging habitat for bumble bees and enhancing crop pollination services.
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Maebe K, Meeus I, Ganne M, De Meulemeester T, Biesmeijer K, Smagghe G. Microsatellite Analysis of Museum Specimens Reveals Historical Differences in Genetic Diversity between Declining and More Stable Bombus Species. PLoS One 2015; 10:e0127870. [PMID: 26061732 PMCID: PMC4464549 DOI: 10.1371/journal.pone.0127870] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 04/21/2015] [Indexed: 11/19/2022] Open
Abstract
Worldwide most pollinators, e.g. bumblebees, are undergoing global declines. Loss of genetic diversity can play an essential role in these observed declines. In this paper, we investigated the level of genetic diversity of seven declining Bombus species and four more stable species with the use of microsatellite loci. Hereto we genotyped a unique collection of museum specimens. Specimens were collected between 1918 and 1926, in 6 provinces of the Netherlands which allowed us to make interspecific comparisons of genetic diversity. For the stable species B. pascuorum, we also selected populations from two additional time periods: 1949-1955 and 1975-1990. The genetic diversity and population structure in B. pascuorum remained constant over the three time periods. However, populations of declining bumblebee species showed a significantly lower genetic diversity than co-occurring stable species before their major declines. This historical difference indicates that the repeatedly observed reduced genetic diversity in recent populations of declining bumblebee species is not caused solely by the decline itself. The historically low genetic diversity in the declined species may be due to the fact that these species were already rare, making them more vulnerable to the major drivers of bumblebee decline.
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Affiliation(s)
- Kevin Maebe
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, Ghent, Belgium
| | - Ivan Meeus
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, Ghent, Belgium
| | - Maarten Ganne
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, Ghent, Belgium
| | | | - Koos Biesmeijer
- Naturalis Biodiversity Center, Darwinweg 2, Leiden, the Netherlands
| | - Guy Smagghe
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, Ghent, Belgium
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19
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Gradish AE, Keyghobadi N, Otis GW. Population genetic structure and genetic diversity of the threatened White Mountain arctic butterfly (Oeneis melissa semidea). CONSERV GENET 2015. [DOI: 10.1007/s10592-015-0736-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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20
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Woodard SH, Lozier JD, Goulson D, Williams PH, Strange JP, Jha S. Molecular tools and bumble bees: revealing hidden details of ecology and evolution in a model system. Mol Ecol 2015; 24:2916-36. [PMID: 25865395 DOI: 10.1111/mec.13198] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 04/07/2015] [Accepted: 04/08/2015] [Indexed: 01/15/2023]
Abstract
Bumble bees are a longstanding model system for studies on behaviour, ecology and evolution, due to their well-studied social lifestyle, invaluable role as wild and managed pollinators, and ubiquity and diversity across temperate ecosystems. Yet despite their importance, many aspects of bumble bee biology have remained enigmatic until the rise of the genetic and, more recently, genomic eras. Here, we review and synthesize new insights into the ecology, evolution and behaviour of bumble bees that have been gained using modern genetic and genomic techniques. Special emphasis is placed on four areas of bumble bee biology: the evolution of eusociality in this group, population-level processes, large-scale evolutionary relationships and patterns, and immunity and resistance to pesticides. We close with a prospective on the future of bumble bee genomics research, as this rapidly advancing field has the potential to further revolutionize our understanding of bumble bees, particularly in regard to adaptation and resilience. Worldwide, many bumble bee populations are in decline. As such, throughout the review, connections are drawn between new molecular insights into bumble bees and our understanding of the causal factors involved in their decline. Ongoing and potential applications to bumble bee management and conservation are also included to demonstrate how genetics- and genomics-enabled research aids in the preservation of this threatened group.
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Affiliation(s)
- S Hollis Woodard
- Department of Integrative Biology, University of Texas, Austin, TX, 78712, USA.,Department of Entomology, University of California, Riverside, CA, 92521, USA
| | - Jeffrey D Lozier
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL, 35401, USA
| | - David Goulson
- Evolution, Behaviour & Environment, School of Life Sciences, University of Sussex, Falmer, East Sussex, BN1 9QG, UK
| | - Paul H Williams
- Department of Life Sciences, Natural History Museum, London, SW7 5BD, UK
| | - James P Strange
- USDA-ARS, Pollinating Insect Research Unit, Utah State University, Logan, UT, 84322, USA
| | - Shalene Jha
- Department of Integrative Biology, University of Texas, Austin, TX, 78712, USA
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21
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Wood TJ, Holland JM, Hughes WOH, Goulson D. Targeted agri-environment schemes significantly improve the population size of common farmland bumblebee species. Mol Ecol 2015; 24:1668-80. [DOI: 10.1111/mec.13144] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 02/20/2015] [Accepted: 03/03/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Thomas J. Wood
- School of Life Sciences; The University of Sussex; Falmer East Sussex BN1 9QG UK
| | - John M. Holland
- The Game and Wildlife Conservation Trust; Burgate Manor; Fordingbridge Hampshire SP6 1EF UK
| | - William O. H. Hughes
- School of Life Sciences; The University of Sussex; Falmer East Sussex BN1 9QG UK
| | - Dave Goulson
- School of Life Sciences; The University of Sussex; Falmer East Sussex BN1 9QG UK
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Crowther LP, Hein PL, Bourke AFG. Habitat and forage associations of a naturally colonising insect pollinator, the tree bumblebee Bombus hypnorum. PLoS One 2014; 9:e107568. [PMID: 25259579 PMCID: PMC4178030 DOI: 10.1371/journal.pone.0107568] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 08/11/2014] [Indexed: 11/28/2022] Open
Abstract
Bumblebees (Bombus species) are major pollinators of commercial crops and wildflowers but factors affecting their abundance, including causes of recent population declines, remain unclear. Investigating the ecology of species with expanding ranges provides a potentially powerful means of elucidating these factors. Such species may also bring novel pollination services to their new ranges. We therefore investigated landscape-scale habitat use and foraging preferences of the Tree Bumblebee, B. hypnorum, a recent natural colonist that has rapidly expanded its range in the UK over the past decade. Counts of B. hypnorum and six other Bombus species were made in March-June 2012 within a mixed landscape in south-eastern Norfolk, UK. The extent of different landscape elements around each transect was quantified at three scales (250 m, 500 m and 1500 m). We then identified the landscape elements that best predicted the density of B. hypnorum and other Bombus species. At the best fitting scale (250 m), B. hypnorum density was significantly positively associated with extent of both urban and woodland cover and significantly negatively associated with extent of oilseed rape cover. This combination of landscape predictors was unique to B. hypnorum. Urban and woodland cover were associated with B. hypnorum density at three and two, respectively, of the three scales studied. Relative to other Bombus species, B. hypnorum exhibited a significantly higher foraging preference for two flowering trees, Crataegus monogyna and Prunus spinosa, and significantly lower preferences for Brassica napus, Glechoma hederacea and Lamium album. Our study provides novel, quantitative support for an association of B. hypnorum with urban and woodland landscape elements. Range expansion in B. hypnorum appears to depend, on exploitation of widespread habitats underutilised by native Bombus species, suggesting B. hypnorum will readily co-exist with these species. These findings suggest that management could target bumblebee species with distinctive habitat requirements to help maintain pollination services.
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Affiliation(s)
- Liam P. Crowther
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk, United Kingdom
- * E-mail:
| | - Pierre-Louis Hein
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk, United Kingdom
- IUT Nancy-Brabois, Rue du Doyen Urion, Villers-les-Nancy CS, France
| | - Andrew F. G. Bourke
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk, United Kingdom
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Dreier S, Redhead JW, Warren IA, Bourke AFG, Heard MS, Jordan WC, Sumner S, Wang J, Carvell C. Fine-scale spatial genetic structure of common and declining bumble bees across an agricultural landscape. Mol Ecol 2014; 23:3384-95. [PMID: 24980963 PMCID: PMC4142012 DOI: 10.1111/mec.12823] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 05/07/2014] [Accepted: 05/21/2014] [Indexed: 02/04/2023]
Abstract
Land-use changes have threatened populations of many insect pollinators, including bumble bees. Patterns of dispersal and gene flow are key determinants of species' ability to respond to land-use change, but have been little investigated at a fine scale (<10 km) in bumble bees. Using microsatellite markers, we determined the fine-scale spatial genetic structure of populations of four common Bombus species (B. terrestris, B. lapidarius, B. pascuorum and B. hortorum) and one declining species (B. ruderatus) in an agricultural landscape in Southern England, UK. The study landscape contained sown flower patches representing agri-environment options for pollinators. We found that, as expected, the B. ruderatus population was characterized by relatively low heterozygosity, number of alleles and colony density. Across all species, inbreeding was absent or present but weak (FIS = 0.01-0.02). Using queen genotypes reconstructed from worker sibships and colony locations estimated from the positions of workers within these sibships, we found that significant isolation by distance was absent in B. lapidarius, B. hortorum and B. ruderatus. In B. terrestris and B. pascuorum, it was present but weak; for example, in these two species, expected relatedness of queens founding colonies 1 m apart was 0.02. These results show that bumble bee populations exhibit low levels of spatial genetic structure at fine spatial scales, most likely because of ongoing gene flow via widespread queen dispersal. In addition, the results demonstrate the potential for agri-environment scheme conservation measures to facilitate fine-scale gene flow by creating a more even distribution of suitable habitats across landscapes.
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Affiliation(s)
- Stephanie Dreier
- Institute of Zoology, Zoological Society of London, Regent's Park, London, NW1 4RY, UK; School of Biological Sciences, University of Bristol, Woodland Road, Bristol, BS8 1UG, UK
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Lozier JD. Revisiting comparisons of genetic diversity in stable and declining species: assessing genome-wide polymorphism in North American bumble bees using RAD sequencing. Mol Ecol 2014; 23:788-801. [DOI: 10.1111/mec.12636] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Revised: 12/10/2013] [Accepted: 12/13/2013] [Indexed: 02/02/2023]
Affiliation(s)
- J. D. Lozier
- Department of Biological Sciences; University of Alabama; Tuscaloosa AL 35487 USA
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Stanley DA, Knight ME, Stout JC. Ecological Variation in Response to Mass-Flowering Oilseed Rape and Surrounding Landscape Composition by Members of a Cryptic Bumblebee Complex. PLoS One 2013; 8:e65516. [PMID: 23840338 PMCID: PMC3686753 DOI: 10.1371/journal.pone.0065516] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 05/02/2013] [Indexed: 11/18/2022] Open
Abstract
The Bombus sensu stricto species complex is a widespread group of cryptic bumblebee species which are important pollinators of many crops and wild plants. These cryptic species have, until now, largely been grouped together in ecological studies, and so little is known about their individual colony densities, foraging ranges or habitat requirements, which can be influenced by land use at a landscape scale. We used mass-flowering oilseed rape fields as locations to sample bees of this complex, as well as the second most common visitor to oilseed rape B. lapidarius, and molecular RFLP methods to distinguish between the cryptic species. We then used microsatellite genotyping to identify sisters and estimate colony densities, and related both proportions of cryptic species and their colony densities to the composition of the landscape surrounding the fields. We found B. lucorum was the most common member of the complex present in oilseed rape followed by B. terrestris. B. cryptarum was also present in all but one site, with higher proportions found in the east of the study area. High numbers of bumblebee colonies were estimated to be using oilseed rape fields as a forage resource, with B. terrestris colony numbers higher than previous estimates from non-mass-flowering fields. We also found that the cryptic species responded differently to surrounding landscape composition: both relative proportions of B. cryptarum in samples and colony densities of B. lucorum were negatively associated with the amount of arable land in the landscape, while proportions and colony densities of other species did not respond to landscape variables at the scale measured. This suggests that the cryptic species have different ecological requirements (which may be scale-dependent) and that oilseed rape can be an important forage resource for many colonies of bumblebees. Given this, we recommend sustainable management of this crop to benefit bumblebees.
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Affiliation(s)
- Dara A. Stanley
- Botany Department, School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
- Trinity Centre for Biodiversity Research, Trinity College Dublin, Dublin, Ireland
- * E-mail:
| | - Mairi E. Knight
- School of Biomedical and Biological Sciences, Plymouth University, Drake Circus, Plymouth, United Kingdom
| | - Jane C. Stout
- Botany Department, School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
- Trinity Centre for Biodiversity Research, Trinity College Dublin, Dublin, Ireland
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Lack of variation at phosphoglucose isomerase (pgi) in bumblebees: implications for conservation genetics studies. PLoS One 2013; 8:e65600. [PMID: 23750269 PMCID: PMC3672202 DOI: 10.1371/journal.pone.0065600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 04/29/2013] [Indexed: 11/30/2022] Open
Abstract
Assessing genetic variation underlying ecologically important traits is increasingly of interest and importance in population and conservation genetics. For some groups generally useful markers exist for examining the relative role of selection and drift in shaping genetic diversity e.g. the major histocompatibility complex in vertebrates and self-incompatibility loci in plants. For invertebrates there is no such generally useful locus. However, phosphoglucose isomerase (Pgi) has been proposed as a useful functional marker in the conservation genetics of invertebrates. Where thermal microclimate varies, balanced polymorphisms may be maintained due to trade-offs between thermally stable and kinetically advantageous allelic forms. We here report very low levels of Pgi variation in bumblebees rendering this locus to be of little use as an adaptive marker in a conservation genetics context in this group. Potential explanations for this lack of variation are considered.
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27
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Ellis JS, Turner LM, Knight ME. Patterns of selection and polymorphism of innate immunity genes in bumblebees (Hymenoptera: Apidae). Genetica 2012; 140:205-17. [PMID: 22899493 DOI: 10.1007/s10709-012-9672-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 08/07/2012] [Indexed: 01/22/2023]
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28
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Lozier JD, Strange JP, Stewart IJ, Cameron SA. Patterns of range-wide genetic variation in six North American bumble bee (Apidae: Bombus) species. Mol Ecol 2011; 20:4870-88. [PMID: 22035452 DOI: 10.1111/j.1365-294x.2011.05314.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The increasing evidence for population declines in bumble bee (Bombus) species worldwide has accelerated research efforts to explain losses in these important pollinators. In North America, a number of once widespread Bombus species have suffered serious reductions in range and abundance, although other species remain healthy. To examine whether declining and stable species exhibit different levels of genetic diversity or population fragmentation, we used microsatellite markers to genotype populations sampled across the geographic distributions of two declining (Bombus occidentalis and Bombus pensylvanicus) and four stable (Bombus bifarius; Bombus vosnesenskii; Bombus impatiens and Bombus bimaculatus) Bombus species. Populations of declining species generally have reduced levels of genetic diversity throughout their range compared to codistributed stable species. Genetic diversity can be affected by overall range size and degree of isolation of local populations, potentially confounding comparisons among species in some cases. We find no evidence for consistent differences in gene flow among stable and declining species, with all species exhibiting weak genetic differentiation over large distances (e.g. >1000 km). Populations on islands and at high elevations experience relatively strong genetic drift, suggesting that some conditions lead to genetic isolation in otherwise weakly differentiated species. B. occidentalis and B. bifarius exhibit stronger genetic differentiation than the other species, indicating greater phylogeographic structure consistent with their broader geographic distributions across topographically complex regions of western North America. Screening genetic diversity in North American Bombus should prove useful for identifying species that warrant monitoring, and developing management strategies that promote high levels of gene flow will be a key component in efforts to maintain healthy populations.
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Affiliation(s)
- Jeffrey D Lozier
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL 35487, USA.
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29
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Carvell C, Jordan WC, Bourke AFG, Pickles R, Redhead JW, Heard MS. Molecular and spatial analyses reveal links between colony-specific foraging distance and landscape-level resource availability in two bumblebee species. OIKOS 2011. [DOI: 10.1111/j.1600-0706.2011.19832.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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30
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Spatial and temporal dynamics of the male effective population size in bumblebees (Hymenoptera: Apidae). POPUL ECOL 2011. [DOI: 10.1007/s10144-011-0285-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Abstract
SUMMARY
Flying is an ecologically important behaviour in many insects, but it often results in permanent wing damage. Although wing wear in insects is often used as a method to determine insect age, and is associated with an increased risk of mortality, the causes of wing wear are unresolved. In this paper, we examine whether wing use while foraging explains wing wear in bumble bees (Bombus spp.). Wing wear may result from three distinct flight characteristics during foraging: time spent in flight, flight frequency and frequency of wing collisions with vegetation. To test these hypotheses for causes of wing wear, we recorded digital video of individually marked bumble bees foraging in nature on 12 different plant species that result in variation in these flight characteristics, and recaptured these individuals to photograph their wings over time. Bumble bees with a higher frequency of wing collisions showed an increased loss of wing area, which became more severe over time. Neither time in flight nor flight frequency was uniquely and significantly associated with wing wear. Therefore, the collision frequency hypothesis best explained wing wear in bumble bees. We conclude that wing use during foraging in bumble bees results in wing wear. Wing wear reflects behaviour, not simply age. Because wing wear has elsewhere been shown to increase mortality, this study provides an important mechanism linking foraging behaviour with lifespan.
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Affiliation(s)
- Danusha J. Foster
- Department of Biological Sciences and Biogeoscience Institute, University of Calgary, 2500 University Drive NW, Calgary, AB, Canada, T2N 1N4
| | - Ralph V. Cartar
- Department of Biological Sciences and Biogeoscience Institute, University of Calgary, 2500 University Drive NW, Calgary, AB, Canada, T2N 1N4
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32
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Population structure, dispersal and colonization history of the garden bumblebee Bombus hortorum in the Western Isles of Scotland. CONSERV GENET 2011. [DOI: 10.1007/s10592-011-0190-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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