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Laursen WJ, Tang R, Garrity PA. Hunting with heat: thermosensory-driven foraging in mosquitoes, snakes and beetles. J Exp Biol 2023; 226:jeb229658. [PMID: 37382467 PMCID: PMC10323236 DOI: 10.1242/jeb.229658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2023]
Abstract
Animals commonly use thermosensation, the detection of temperature and its variation, for defensive purposes: to maintain appropriate body temperature and to avoid tissue damage. However, some animals also use thermosensation to go on the offensive: to hunt for food. The emergence of heat-dependent foraging behavior has been accompanied by the evolution of diverse thermosensory organs of often exquisite thermosensitivity. These organs detect the heat energy emitted from food sources that range from nearby humans to trees burning in a forest kilometers away. Here, we examine the biophysical considerations, anatomical specializations and molecular mechanisms that underlie heat-driven foraging. We focus on three groups of animals that each meet the challenge of detecting heat from potential food sources in different ways: (1) disease-spreading vector mosquitoes, which seek blood meals from warm-bodied hosts at close range, using warming-inhibited thermosensory neurons responsive to conductive and convective heat flow; (2) snakes (vipers, pythons and boas), which seek warm-blooded prey from ten or more centimeters away, using warmth-activated thermosensory neurons housed in an organ specialized to harvest infrared radiation; and (3) fire beetles, which maximize their offspring's feeding opportunities by seeking forest fires from kilometers away, using mechanosensory neurons housed in an organ specialized to convert infrared radiation into mechanosensory stimuli. These examples highlight the diverse ways in which animals exploit the heat emanating from potential food sources, whether this heat reflects ongoing metabolic activity or a recent lightning strike, to secure a nutritious meal for themselves or for their offspring.
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Affiliation(s)
- Willem J. Laursen
- Department of Biology and Volen Center for Complex Systems, Brandeis University, Waltham, MA 02453, USA
| | - Ruocong Tang
- Department of Biology and Volen Center for Complex Systems, Brandeis University, Waltham, MA 02453, USA
| | - Paul A. Garrity
- Department of Biology and Volen Center for Complex Systems, Brandeis University, Waltham, MA 02453, USA
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Liao C, Amador GJ, Liu X, Wu Z, Wu J. Trichoid sensilla on honey bee proboscises as inspiration for micro-viscometers. BIOINSPIRATION & BIOMIMETICS 2022; 18:016012. [PMID: 36541491 DOI: 10.1088/1748-3190/aca577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
Sensing physical properties of liquids, such as viscosity, is of great significance for both biological organisms and industrial applications. For terrestrial organisms feeding on liquids, such as honey bees that forage nectar, sensing viscosity may help to determine the quality of food sources. Previous experiments showed that honey bees exhibit strong preferences for less viscous nectar; however, the physical mechanism underlying how they perceive viscosity remains unexplored. In this study, we propose that the western honey bee (Apis melliferaL.) is capable of distinguishing viscosity using the slender trichoid sensilla emerging from a ball and socket-like joint on the proboscis. Observations of the trichoid sensilla using transmission electron microscopy reveal physical characteristics that are typical of mechanosensory structures. Additionally, we found that bees actively alter the rate at which they feed based on the liquid's viscosity and not its sugar content, hinting at their sensing of viscosity. Through mathematical modeling, we found that the sensitivity of the biological viscometer was determined by its length, and the optimal sensitivity for a western honey bee occurs when the tongue interacts with nectar with a viscosity of 4.2 mPa·s, coinciding with the viscosities typically found in the wild. Our findings broaden insights into how honey bees adapt to varying-viscosity nectar from the perspective of mechanical sensing, and how the bee-flower partnership may be based around the optimal nectar viscosity for feeding. By understanding how bees may sense viscosity at the micrometer scale, we may motivate new technologies for micro-viscometers.
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Affiliation(s)
- Caiying Liao
- School of Aeronautics and Astronautics, Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, People's Republic of China
| | - Guillermo J Amador
- Experimental Zoology Group, Wageningen University & Research, Wageningen, 6708 WD, The Netherlands
| | - Xuhan Liu
- School of Aeronautics and Astronautics, Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, People's Republic of China
| | - Zhigang Wu
- School of Aeronautics and Astronautics, Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, People's Republic of China
| | - Jianing Wu
- School of Aeronautics and Astronautics, Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, People's Republic of China
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3
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Nicolson SW, Human H, Pirk CWW. Honey bees save energy in honey processing by dehydrating nectar before returning to the nest. Sci Rep 2022; 12:16224. [PMID: 36171276 PMCID: PMC9519551 DOI: 10.1038/s41598-022-20626-5] [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: 07/12/2022] [Accepted: 09/15/2022] [Indexed: 11/09/2022] Open
Abstract
Honey bees process nectar into honey by active evaporation on the tongue and passive evaporation involving nest ventilation and fanning behaviour, as well as enzymatic action. The elimination of excess water from nectar carries considerable energetic costs. The concentration of the nectar load is assumed to remain constant during transport. However, some of this water elimination may occur before foragers return to the nest and pass their nectar loads to receiver bees. In honey bees captured while foraging in Macadamia orchards, we show that the nectar in their crops has approximately twice the sugar concentration of the fresh nectar in flowers. This was true for four Macadamia cultivars, with up to 75% of the initial water content being removed. There is a further concentration increase in the crops of returning bees captured at the hive entrance. The only possible route of water elimination from the crop is via evaporation from the mouthparts. We calculate the savings in honey processing costs to be on average 35 times more than the reduction in flight costs due to reduced body mass. Pre-concentration of nectar in foraging honey bees may be widespread, and of crucial importance for honey storage.
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Affiliation(s)
- Susan W Nicolson
- Department of Zoology and Entomology, University of Pretoria, Pretoria, 0002, South Africa.
| | - Hannelie Human
- Department of Zoology and Entomology, University of Pretoria, Pretoria, 0002, South Africa
| | - Christian W W Pirk
- Department of Zoology and Entomology, University of Pretoria, Pretoria, 0002, South Africa
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Martin VN, Schaeffer RN, Fukami T. Potential effects of nectar microbes on pollinator health. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210155. [PMID: 35491594 DOI: 10.1098/rstb.2021.0155] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Floral nectar is prone to colonization by nectar-adapted yeasts and bacteria via air-, rain-, and animal-mediated dispersal. Upon colonization, microbes can modify nectar chemical constituents that are plant-provisioned or impart their own through secretion of metabolic by-products or antibiotics into the nectar environment. Such modifications can have consequences for pollinator perception of nectar quality, as microbial metabolism can leave a distinct imprint on olfactory and gustatory cues that inform foraging decisions. Furthermore, direct interactions between pollinators and nectar microbes, as well as consumption of modified nectar, have the potential to affect pollinator health both positively and negatively. Here, we discuss and integrate recent findings from research on plant-microbe-pollinator interactions and their consequences for pollinator health. We then explore future avenues of research that could shed light on the myriad ways in which nectar microbes can affect pollinator health, including the taxonomic diversity of vertebrate and invertebrate pollinators that rely on this reward. This article is part of the theme issue 'Natural processes influencing pollinator health: from chemistry to landscapes'.
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Affiliation(s)
| | | | - Tadashi Fukami
- Department of Biology, Stanford University, Stanford, CA, USA
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5
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Geest EA, Baum KA. The Impact of Fire on Nectar Quality and Quantity for Insect Pollinator Communities. AMERICAN MIDLAND NATURALIST 2022. [DOI: 10.1674/0003-0031-187.2.268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Emily A. Geest
- Department of Integrative Biology, Oklahoma State University, 501 Life Sciences West, Stillwater 74078
| | - Kristen A. Baum
- Department of Integrative Biology, Oklahoma State University, 501 Life Sciences West, Stillwater 74078
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Maluf RP, Alzate-Marin AL, Silva CC, Pansarin LM, Bonifácio-Anacleto F, Schuster I, de Mello Prado R, Martinez CA. Warming and soil water availability affect plant-flower visitor interactions for Stylosanthes capitata, a tropical forage legume. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 817:152982. [PMID: 35031369 DOI: 10.1016/j.scitotenv.2022.152982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 01/03/2022] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
The reproductive success of a zoophilous plant species depends on biological interaction with pollinators, which involves both the provision and exploitation of flower resources. Currently, there is little information about how future climate change scenarios will impact interactions between plants and their flower visitors in the tropics. This study analyzes the effects of warming and two soil water conditions on interactions between the tropical forage legume species Stylosanthes capitata and its floral visitors during the flowering period. We used a temperature-free air-controlled enhancement (T-FACE) facility to simulate future warming scenarios by increasing canopy temperature. The tested treatments were: irrigated and ambient canopy temperature (Control); non-irrigated and ambient canopy temperature (wS); irrigated and elevated canopy temperature (eT, +2 °C above ambient canopy temperature); and non-irrigated and elevated canopy temperature (wSeT). The effects of treatments on the time of flower opening and closing, sugar concentration in the nectar, and plant-flower visitor interactions were assessed. In the warmed treatments, S. capitata flower opening occurred ~45 min earlier compared to non-warmed treatments, and flowers remained opened for only ~3 h. Further, the sugar concentration in the nectar from eT was 39% higher than in the Control. The effects of warming on floral biology and flower resource production in S. capitata had an impact on the plant-floral visitor relationships with the bees Apis mellifera and Paratrigona lineata, the most abundant potential pollinating floral visitors, and the butterfly visitor Hemiargus hanno. Additionally, around noon, the interactive and additive effects of the combined wS and eT treatments decreased insect visiting frequency. These results suggest that warming and soil water deficiency could affect flower-visitor interactions and thus the reproductive success of S. capitata in tropical belts.
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Affiliation(s)
- Raquel Pérez Maluf
- Department of Natural Sciences, Semi-Arid Biodiversity Laboratory - Labisa, State University of Southwest Bahia, Estrada do Bem Querer, Km 04, UESB, 45031-900 Vitoria da Conquista, BA, Brazil
| | - Ana Lilia Alzate-Marin
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil; Department of Genetics, Graduate Program in Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil.
| | - Carolina Costa Silva
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil
| | - Ludmila Mickeliunas Pansarin
- Department of Biology, Ribeirão Preto School of Philosophy, Science and Literature, University of São Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirão Preto, SP, Brazil
| | - Fernando Bonifácio-Anacleto
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil; Department of Genetics, Graduate Program in Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil
| | - Ivan Schuster
- Longping High-Tech, SP-330, km 296, 14140-000 Cravinhos, SP, Brazil
| | - Renato de Mello Prado
- Department of Agricultural Production Sciences, School of Agricultural and Veterinary Sciences, University of São Paulo State, Via de Acesso Prof. Paulo Donato Castellane, s/n, 14884-900 Jaboticabal, SP, Brazil
| | - Carlos A Martinez
- Department of Biology, Ribeirão Preto School of Philosophy, Science and Literature, University of São Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirão Preto, SP, Brazil.
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Tiwari S, Jadhav R, Avchar R, Lanjekar V, Datar M, Baghela A. Nectar Yeast Community of Tropical Flowering Plants and Assessment of Their Osmotolerance and Xylitol-Producing Potential. Curr Microbiol 2021; 79:28. [PMID: 34905093 DOI: 10.1007/s00284-021-02700-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 11/03/2021] [Indexed: 11/29/2022]
Abstract
Floral nectar is colonised by microbes, especially yeasts which alter the scent, temperature, and chemical composition of nectar, thereby playing an essential role in pollination. The yeast communities inhabiting the nectar of tropical flowers of India are not well explored. We isolated 48 yeast strains from seven different tropical flowering plants. Post MSP-PCR-based screening, 23 yeast isolates and two yeast-like fungi were identified, which belonged to 16 species of 12 genera viz. Candida (2 species), Aureobasidium (2 species), Metschnikowia (2 species), Meyerozyma (1 species), Saitozyma (1 species), Wickerhamomyces (1 species), Kodamaea (2 species), Pseudozyma (1 species), Starmerella (1 species), Hanseniaspora (1 species), Rhodosporidiobolus (1 species), Moesziomyces (1 species), and two putative novel species. All yeast strains were assessed for their osmotolerance abilities in high salt and sugar concentration. Among all the isolates, C. nivariensis (SRA2.2, SRA1.1 and SRA2.1), M. caribbica (SRA4.8 and SRA4.6), S. flava SRA4.2, and M. reukaufii SRA3.2 showed significant growth in high concentrations of sugar (40-50% glucose), as well as salt (12-15% NaCl). All 25 strains were also screened for their ability to utilise xylose to produce xylitol. Meyerozyma caribbica was the most efficient xylitol producer, wherein three strains of this species (SRA4.6, SRA4.1, and SRA4.8) generated 18.61 to 21.56 g l-1 of xylitol, with 0.465-0.539 g g-1 yields. Through this study, we draw attention towards the tropical floral nectar as a potential niche for the isolation of diverse, osmotolerant, and xylitol-producing yeasts. Such osmotolerant yeasts have potential applications in food industries and biofuel production.
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Affiliation(s)
- Snigdha Tiwari
- National Fungal Culture Collection of India (NFCCI), Biodiversity and Palaeobiology Group, MACS-Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India.,Savitribai Phule Pune University, Ganeshkhind, Pune, 411007, India
| | - Reshma Jadhav
- National Fungal Culture Collection of India (NFCCI), Biodiversity and Palaeobiology Group, MACS-Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India
| | - Rameshwar Avchar
- National Fungal Culture Collection of India (NFCCI), Biodiversity and Palaeobiology Group, MACS-Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India.,Savitribai Phule Pune University, Ganeshkhind, Pune, 411007, India
| | - Vikram Lanjekar
- Bioenergy Group, MACS-Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India
| | - Mandar Datar
- Biodiversity and Palaeobiology Group, Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India
| | - Abhishek Baghela
- National Fungal Culture Collection of India (NFCCI), Biodiversity and Palaeobiology Group, MACS-Agharkar Research Institute, G.G. Agarkar Road, Pune, 411004, India. .,Savitribai Phule Pune University, Ganeshkhind, Pune, 411007, India.
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8
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Wang H, Wu Z, Zhao J, Wu J. Nectar Feeding by a Honey Bee's Hairy Tongue: Morphology, Dynamics, and Energy-Saving Strategies. INSECTS 2021; 12:insects12090762. [PMID: 34564203 PMCID: PMC8465255 DOI: 10.3390/insects12090762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 08/13/2021] [Accepted: 08/18/2021] [Indexed: 11/16/2022]
Abstract
Simple Summary This paper reviews the interdisciplinary research on nectar feeding behaviour of honey bees ranging from morphology, dynamics, and energy-saving strategies, which collects a range of knowledge of feeding physiology of honey bees and may inspire the design paradigms of next-generation multifunctional microfluidic transporters. Abstract Most flower-visiting insects have evolved highly specialized morphological structures to facilitate nectar feeding. As a typical pollinator, the honey bee has specialized mouth parts comprised of a pair of galeae, a pair of labial palpi, and a glossa, to feed on the nectar by the feeding modes of lapping or sucking. To extensively elucidate the mechanism of a bee’s feeding, we should combine the investigations from glossa morphology, feeding behaviour, and mathematical models. This paper reviews the interdisciplinary research on nectar feeding behaviour of honey bees ranging from morphology, dynamics, and energy-saving strategies, which may not only reveal the mechanism of nectar feeding by honey bees but inspire engineered facilities for microfluidic transport.
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Affiliation(s)
- Hao Wang
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Guangzhou 510006, China; (H.W.); (Z.W.)
| | - Zhigang Wu
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Guangzhou 510006, China; (H.W.); (Z.W.)
| | - Jieliang Zhao
- School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China;
| | - Jianing Wu
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Guangzhou 510006, China; (H.W.); (Z.W.)
- Correspondence:
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Measuring foraging preferences in bumble bees: a comparison of popular laboratory methods and a test for sucrose preferences following neonicotinoid exposure. Oecologia 2021; 196:963-976. [PMID: 34250559 DOI: 10.1007/s00442-021-04979-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 06/23/2021] [Indexed: 10/20/2022]
Abstract
Animals develop food preferences based on taste, nutritional quality and to avoid environmental toxins. Yet, measuring preferences in an experimental setting can be challenging since ecologically realistic assays can be time consuming, while simplified assays may not capture natural sampling behavior. Field realism is a particular challenge when studying behavioral responses to environmental toxins in lab-based assays, given that toxins can themselves impact sampling behavior, masking our ability to detect preferences. We address these challenges by comparing different experimental methods for measuring sucrose concentration preference in bumble bees (Bombus impatiens), evaluating the utility of two preference chamber-based methods (ad libitum versus a novel restricted-sampling assay) in replicating bees' preferences when they fly freely between artificial flowers in a foraging arena. We find that the restricted-sampling method matched a free-flying scenario more closely than the ad libitum protocol, and we advocate for expanded use of this approach, given its ease of implementation. We then performed a second experiment using the new protocol to ask whether consuming the neonicotinoid pesticide imidacloprid, known to suppress feeding motivation, interfered with the expression of sucrose preferences. After consuming imidacloprid, bees were less likely to choose the higher-quality sucrose even as they gained experience with both options. Thus, we provide evidence that pesticides interfere with bees' ability to discriminate between floral rewards that differ in value. This work highlights a simple protocol for assessing realistic foraging preferences in bees and provides an efficient way for researchers to measure the impacts of anthropogenic factors on preference expression.
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Alzate-Marin AL, Rivas PMS, Galaschi-Teixeira JS, Bonifácio-Anacleto F, Silva CC, Schuster I, Nazareno AG, Giuliatti S, da Rocha Filho LC, Garófalo CA, Martinez CA. Warming and elevated CO 2 induces changes in the reproductive dynamics of a tropical plant species. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 768:144899. [PMID: 33736351 DOI: 10.1016/j.scitotenv.2020.144899] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 12/28/2020] [Accepted: 12/29/2020] [Indexed: 06/12/2023]
Abstract
Tropical plant species are vulnerable to climate change and global warming. Since flowering is a critical factor for plant reproduction and seed-set, warming and elevated atmospheric carbon dioxide concentrations (eCO2) are crucial climate change factors that can affect plant reproductive dynamics and flowering related events in the tropics. Using a combined free-air CO2 enrichment and a free-air temperature-controlled enhancement system, we investigate how warming (+2 °C above ambient, eT) and elevated [CO2] (~600 ppm, eCO2) affect the phenological pattern, plant-insect interactions, and outcrossing rates in the tropical legume forage species Stylosanthes capitata Vogel (Fabaceae). In comparison to the control, a significantly greater number of flowers (NF) per plot (+62%) were observed in eT. Furthermore, in warmed plots flowers began opening approximately 1 h earlier (~09:05), with a canopy temperature of ~23 °C, than the control (~09:59) and eCO2 (~09:55) treatments. Flower closure occurred about 3 h later in eT (~11:57) and control (~13:13), with a canopy temperature of ~27 °C. These changes in flower phenology increased the availability of floral resources and attractiveness for pollinators such as Apis mellifera L. and visitors such as Paratrigona lineata L., with significant interactions between eT treatments and insect visitation per hour/day, especially between 09:00-10:40. In comparison to the control, the additive effects of combined eCO2 + eT enhanced the NF by 137%, while the number of A. mellifera floral visits per plot/week increased by 83% during the period of greatest flower production. Although we found no significant effect of treatments on mating system parameters, the overall mean multilocus outcrossing rate (tm = 0.53 ± 0.03) did confirm that S. capitata has a mixed mating system. The effects of elevated [CO2] and warming on plant-pollinator relationships observed here may have important implications for seed production of tropical forage species in future climate scenarios.
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Affiliation(s)
- Ana Lilia Alzate-Marin
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil; Department of Genetics, Graduate Program in Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil.
| | - Priscila Marlys Sá Rivas
- Department of Genetics, Graduate Program in Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil
| | - Juliana S Galaschi-Teixeira
- Department of Biology, Ribeirão Preto School of Philosophy, Science and Literature, University of São Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirão Preto, SP, Brazil
| | - Fernando Bonifácio-Anacleto
- Department of Genetics, Graduate Program in Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil
| | - Carolina Costa Silva
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil
| | - Ivan Schuster
- Longping High-Tech, SP-330, km 296, 14140-000 Cravinhos, SP, Brazil
| | - Alison Gonçalves Nazareno
- The Biosciences Institute (IB), University of São Paulo, Rua do Matão, Tv. 14 - Butantã, 05508-090 São Paulo, SP, Brazil; Department of Genetics, Ecology and Evolution, Federal University of Minas Gerais (UFMG), Av. Antônio Carlos, 6627 - Pampulha/Caixa Postal 486, 31270-901 Belo Horizonte, MG, Brazil
| | - Silvana Giuliatti
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil; Department of Genetics, Graduate Program in Genetics, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, SP, Brazil
| | - Léo Correia da Rocha Filho
- Department of Biology, Ribeirão Preto School of Philosophy, Science and Literature, University of São Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirão Preto, SP, Brazil
| | - Carlos A Garófalo
- Department of Biology, Ribeirão Preto School of Philosophy, Science and Literature, University of São Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirão Preto, SP, Brazil
| | - Carlos A Martinez
- Department of Biology, Ribeirão Preto School of Philosophy, Science and Literature, University of São Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirão Preto, SP, Brazil.
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11
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Colda A, Bossaert S, Verreth C, Vanhoutte B, Honnay O, Keulemans W, Lievens B. Inoculation of pear flowers with Metschnikowia reukaufii and Acinetobacter nectaris enhances attraction of honeybees and hoverflies, but does not increase fruit and seed set. PLoS One 2021; 16:e0250203. [PMID: 33886638 PMCID: PMC8061982 DOI: 10.1371/journal.pone.0250203] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 04/02/2021] [Indexed: 11/28/2022] Open
Abstract
Currently, one of the most important challenges is to provide sufficient and affordable food and energy for a fast-growing world population, alongside preserving natural habitats and maintaining biodiversity. About 35% of the global food production depends on animals for pollination. In recent years, an alarming worldwide decline in pollinators has been reported, putting our food production under additional pressure. Therefore, there is an urgent need to find sustainable ways to ensure this crucial ecosystem service. Recent studies have shown that floral nectar is generally colonized by microorganisms, specifically yeasts and bacteria, which may alter nectar chemistry and enhance attraction of pollinators. In this study, we investigated changes in pollinator foraging behavior and pollination success in European pear (Pyrus communis L.) cultivars 'Regal Red' and 'Sweet Sensation' (red sports of 'Doyenné de Comice') after flower inoculation with the typical nectar-inhabiting microorganisms Metschnikowia reukaufii and Acinetobacter nectaris, and a combination of both. Pollination success was monitored by measuring the number of flower visits, fruit set and seed set in two consecutive years, 2019 and 2020. Results revealed that application of a mixture of M. reukaufii and A. nectaris resulted in significantly higher visitation rates of honeybees and hoverflies. By contrast, no effects on flower visits were found when yeasts and bacteria were applied separately. Fruit set and seed set were not significantly affected by any of the inoculation treatments. The only factors affecting fruit set were initial number of flower clusters on the trees and the year. The absence of treatment effects can most likely be attributed to the fact that pollination was not a limiting factor for fruit set in our experiments. Altogether, our results show that inoculation of flowers with nectar microbes can modify pollinator foraging patterns, but did not lead to increased pollination success under the conditions tested.
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Affiliation(s)
- Agneta Colda
- Division of Crop Biotechnics, Laboratory for Fruit Breeding and Biotechnology, Department of Biosystems, KU Leuven, Leuven, Belgium
| | - Sofie Bossaert
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, Center of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Christel Verreth
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, Center of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Bart Vanhoutte
- Research Center for Fruit Growing, Sint-Truiden, Belgium
| | - Olivier Honnay
- Division of Ecology, Evolution and Biodiversity Conservation, Department of Biology, Plant Conservation and Population Biology, KU Leuven, Leuven, Belgium
| | - Wannes Keulemans
- Division of Crop Biotechnics, Laboratory for Fruit Breeding and Biotechnology, Department of Biosystems, KU Leuven, Leuven, Belgium
| | - Bart Lievens
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, Center of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
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12
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Lois-Milevicich J, Schilman PE, Josens R. Viscosity as a key factor in decision making of nectar feeding ants. JOURNAL OF INSECT PHYSIOLOGY 2021; 128:104164. [PMID: 33220240 DOI: 10.1016/j.jinsphys.2020.104164] [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: 09/28/2020] [Revised: 11/14/2020] [Accepted: 11/16/2020] [Indexed: 06/11/2023]
Abstract
It is well known that viscosity reduces the intake rates in nectar-feeding insects, such as nectivorous ants, though it remains unclear whether viscosity imposes a higher energy investment in these insects, and how this affects their feeding motivation. To address this issue, we studied feeding behavior, metabolism, and pharyngeal pump activity in the carpenter ant Camponotus mus during ingestion of ad libitum sucrose solutions. In some solutions tylose was added to modify viscosity without changing its sucrose concentration, in a way that allowed comparing: (1) two solutions with the same viscosity and different sucrose concentration (10 T and 50), and (2) two solutions with different viscosity and the same sucrose concentration (50 and 50 T). The viscosity increase was detrimental to the metabolic rate and energy balance. Ants feeding on a solution with high sucrose concentration and increased viscosity (50 T) spent extra-time until reaching a crop load similar to that reached by ingesting the solution without tylose (50). For all solutions offered, ants started feeding with the same pharyngeal pump frequencies, reflecting a similar motivation. Interesting, when ants fed on a low sucrose concentration and increased viscosity solution (10 T), their pump frequencies dropped rapidly respect to the pure-sucrose solution (50). On the contrary, pump frequencies for 50 and 50 T remained similar until the end of the intake. Since the pump frequency is strongly modulated by the ant motivation, an increase in viscosity with low sucrose content, demotivates the ants rapidly, suggesting a rapid integration of different kinds of information about the food value. Our results helped to understand how nectivorous ants could modulate their foraging decision-making.
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Affiliation(s)
- Jimena Lois-Milevicich
- Laboratorio de Insectos Sociales, Departamento de Biodiversidad y Biología Experimental and Instituto de Fisiología y Biología Molecular y Neurociencias (CONICET), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, (C1428EGA), Buenos Aires, Argentina.
| | - Pablo E Schilman
- Laboratorio de Ecofisiología de Insectos, Departamento de Biodiversidad y Biología Experimental and Instituto de Biodiversidad y Biología Experimental y Aplicada (CONICET), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, (C1428EGA), Buenos Aires, Argentina.
| | - Roxana Josens
- Laboratorio de Insectos Sociales, Departamento de Biodiversidad y Biología Experimental and Instituto de Fisiología y Biología Molecular y Neurociencias (CONICET), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, (C1428EGA), Buenos Aires, Argentina.
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13
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Glaser GL, Miller MC, Healy SD, Shuker DM. The rationality of decisions depends on behavioural context. Behav Processes 2020; 182:104293. [PMID: 33290832 DOI: 10.1016/j.beproc.2020.104293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 11/17/2020] [Accepted: 12/01/2020] [Indexed: 10/22/2022]
Abstract
Decision makers can be described as economically rational (making consistent choices), or economically irrational (making choices that vary with the options available). As the extent to which animals can and do make rational versus irrational decisions remains unclear, we tested the decision-making strategies of female Nasonia vitripennis parasitic wasps in two behavioural contexts: oviposition and foraging. In our first experiment, to determine whether oviposition preferences changed depending on the options available, we presented females with a high and a medium-quality blow fly host to parasitize, and gave some females an additional low or very low quality 'decoy' host. Presence of decoy options did not affect females' oviposition choices, either in willingness to parasitize a host or the number of offspring laid. In our second experiment, we tested the effects of a low-quality decoy option on foraging preference for a high and a medium-quality sucrose concentration option. Here, presence of the low-quality decoy enhanced female preference for the high-quality option. Females therefore made economically rational decisions when ovipositing and economically irrational decisions when foraging. This difference in decision outcomes suggests that the cost/benefit ratio of making one type of decision over another may differ with the behavioural task.
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Affiliation(s)
- Georgina L Glaser
- Harold Mitchell Building, University of St Andrews, St Andrews, KY16 9TJ, United Kingdom.
| | - Mhairi C Miller
- Harold Mitchell Building, University of St Andrews, St Andrews, KY16 9TJ, United Kingdom
| | - Susan D Healy
- Harold Mitchell Building, University of St Andrews, St Andrews, KY16 9TJ, United Kingdom
| | - David M Shuker
- Harold Mitchell Building, University of St Andrews, St Andrews, KY16 9TJ, United Kingdom
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14
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Hive minded: like neurons, honey bees collectively integrate negative feedback to regulate decisions. Anim Behav 2020. [DOI: 10.1016/j.anbehav.2020.07.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Shi L, Nicolson SW, Yang Y, Wu J, Yan S, Wu Z. Drinking made easier: honey bee tongues dip faster into warmer and/or less viscous artificial nectar. J Exp Biol 2020; 223:jeb229799. [PMID: 32737214 DOI: 10.1242/jeb.229799] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 07/24/2020] [Indexed: 12/11/2022]
Abstract
Optimal concentrations for nectar drinking are limited by the steep increase in the viscosity of sugar solutions with concentration. However, nectar viscosity is inversely related to temperature, which suggests there are advantages to foraging from flowers that are warmer than the surrounding air. The honey bee (Apis mellifera L.) dips nectar using a hairy tongue. However, the microscopic dynamics of the tongue while the bee ingests nectar of varying concentration, viscosity and temperature are unknown. In this study, we found that honey bees respond to the variation of nectar properties by regulating dipping frequency. Through high-speed imaging, we discovered that the honey bee traps warmer sucrose solutions with a quicker tongue. The honey bee dips the warmest and most dilute solution (40°C and 25% w/w sucrose) 1.57 times as fast as the coldest and thickest solution (20°C and 45% w/w sucrose). When the viscosity of different sucrose concentrations was kept constant by adding the inert polysaccharide Tylose, honey bees dipped nectar at constant frequency. We propose a fluid mechanism model to elucidate potential effects on sucrose intake and show that higher dipping frequency can increase the volumetric and energetic intake rates by 125% and 15%, respectively. Our findings broaden insights into how honey bees adapt to foraging constraints from the perspective of tongue dynamics, and demonstrate that elevated intrafloral temperatures and lower nectar viscosity can improve the volumetric and energetic intake rates of pollinators.
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Affiliation(s)
- Lianhui Shi
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Guangzhou 510006, People's Republic of China
- School of Engineering and Technology, China University of Geosciences (Beijing), Beijing 100083, People's Republic of China
| | - Susan W Nicolson
- Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Yunqiang Yang
- School of Engineering and Technology, China University of Geosciences (Beijing), Beijing 100083, People's Republic of China
| | - Jianing Wu
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Guangzhou 510006, People's Republic of China
| | - Shaoze Yan
- Division of Intelligent and Biomechanical Systems, State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Zhigang Wu
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Guangzhou 510006, People's Republic of China
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16
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Wei J, Huo Z, Gorb SN, Rico-Guevara A, Wu Z, Wu J. Sucking or lapping: facultative feeding mechanisms in honeybees ( Apis mellifera). Biol Lett 2020; 16:20200449. [PMID: 32780979 PMCID: PMC7480147 DOI: 10.1098/rsbl.2020.0449] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Accepted: 07/27/2020] [Indexed: 11/12/2022] Open
Abstract
Nectarivorous insects generally adopt suction or lapping to extract nectar from flowers and it is believed that each species exhibits one specific feeding pattern. In recent literature, large groups of nectarivores are classified as either 'suction feeders', imbibing nectar through their proboscis, or 'lappers', using viscous dipping. Honeybees (Apis mellifera) are the well-known lappers by virtue of their hairy tongues. Surprisingly, we found that honeybees also employ active suction when feeding on nectar with low viscosity, defying their classification as lappers. Further experiments showed that suction yielded higher uptake rates when ingesting low-concentration nectar, while lapping resulted in faster uptake when ingesting nectar with higher sugar content. We found that the optimal concentration of suction mode in honeybees coincided with the one calculated for other typical suction feeders. Moreover, we found behavioural flexibility in the drinking mode: a bee is able to switch between lapping and suction when offered different nectar concentrations. Such volitional switching in bees can enhance their feeding capabilities, allowing them to efficiently exploit the variety of concentrations presented in floral nectars, enhancing their adaptability to a wide range of energy sources.
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Affiliation(s)
- Jiangkun Wei
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Guangzhou 510006, People's Republic of China
| | - Zixin Huo
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Guangzhou 510006, People's Republic of China
| | - Stanislav N. Gorb
- Functional Morphology and Biomechanics, Zoology Department, Kiel University, Am Botanischen Garten 9, 24118 Kiel, Germany
| | - Alejandro Rico-Guevara
- Department of Biology, University of Washington, Seattle, WA 98105, USA
- Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98105, USA
| | - Zhigang Wu
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Guangzhou 510006, People's Republic of China
| | - Jianing Wu
- School of Aeronautics and Astronautics, Sun Yat-Sen University, Guangzhou 510006, People's Republic of China
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17
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Pattrick JG, Symington HA, Federle W, Glover BJ. The mechanics of nectar offloading in the bumblebee Bombus terrestris and implications for optimal concentrations during nectar foraging. J R Soc Interface 2020; 17:20190632. [PMID: 31964267 DOI: 10.1098/rsif.2019.0632] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Nectar is a common reward provided by plants for pollinators. More concentrated nectar is more rewarding, but also more viscous, and hence more time-consuming to drink. Consequently, theory predicts an optimum concentration for maximizing energy uptake rate, dependent on the mechanics of feeding. For social pollinators such as bumblebees, another important but little-studied aspect of foraging is nectar offloading upon return to the nest. Studying the bumblebee Bombus terrestris, we found that the relationship between viscosity (µ) and volumetric transfer rates (Q) of sucrose solutions differed between drinking and offloading. For drinking, Q ∝ µ-0.180, in good agreement with previous work. Although offloading was quicker than drinking, offloading rate decreased faster with viscosity, with Q ∝ µ-0.502, consistent with constraints imposed by fluid flow through a tube. The difference in mechanics between drinking and offloading nectar leads to a conflict in the optimum concentration for maximizing energy transfer rates. Building a model of foraging energetics, we show that including offloading lowers the maximum rate of energy return to the nest and reduces the concentration which maximizes this rate by around 3%. Using our model, we show that published values of preferred nectar sugar concentrations suggest that bumblebees maximize the overall energy return rather than the instantaneous energy uptake during drinking.
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Affiliation(s)
- Jonathan G Pattrick
- Department of Zoology, University of Oxford, 11a Mansfield Road, Oxford OX1 3SZ, UK.,Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK.,Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Hamish A Symington
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK
| | - Walter Federle
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Beverley J Glover
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK
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18
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Lechantre A, Michez D, Damman P. Collection of nectar by bumblebees: how the physics of fluid demonstrates the prominent role of the tongue's morphology. SOFT MATTER 2019; 15:6392-6399. [PMID: 31312830 DOI: 10.1039/c9sm00982e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Bumblebees and some other tiny animals feed on nectar by visiting flowers in their neighborhood. Some bee species appear to be highly specialized, their tongue being adapted to specific flowers. Bombus terrestris in contrast is able to feed on a wide variety of flowers and can thus be considered as a kind of universal nectar catcher. Since plant nectars show highly variable sugar content, Bombus terrestris have developed a capture mechanism that works for almost any fluid viscosity. Their tongues are decorated with very elongated papillae forming a hairy coating surrounding a rod-like main stalk. When settled on a flower, Bombus rapidly dip their tongue into the inflorescence to catch the highly sought-after nectar. To determine the physical mechanism at the origin of this outstanding ability, the capture dynamics was followed from videos recorded during viscous fluid ingestion. Surprisingly, the volume per lap and the lapping frequency are independent of the fluid viscosity over three orders of magnitude. To explain this observation, we designed a physical model of viscous dipping with structured rods. Predictions of the model compared to observations for bees showed that the nectar is not captured with the help of viscous drag, as proposed in the Landau-Levich-Derjaguin model, but thanks to the hairy structure that traps the viscous fluid, capillary forces drastically limiting the drainage. Our approach can be transposed to others nectar foragers such as bats and hummingbirds.
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Affiliation(s)
- Amandine Lechantre
- Laboratoire Interfaces & Fluides Complexes, Université de Mons, 20 Place du Parc, B-7000 Mons, Belgium.
| | - Denis Michez
- Institut des Biosciences, Laboratoire de Zoologie, Université de Mons, 20 Place du parc, 7000 Mons, Belgium
| | - Pascal Damman
- Laboratoire Interfaces & Fluides Complexes, Université de Mons, 20 Place du Parc, B-7000 Mons, Belgium.
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19
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George EA, Bröger A, Thamm M, Brockmann A, Scheiner R. Inter‐individual variation in honey bee dance intensity correlates with expression of the
foraging
gene. GENES BRAIN AND BEHAVIOR 2019; 19:e12592. [DOI: 10.1111/gbb.12592] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 05/14/2019] [Accepted: 05/28/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Ebi A. George
- National Centre for Biological Sciences Tata Institute of Fundamental Research Bangalore India
| | - Ann‐Kathrin Bröger
- Behavioral Physiology & Sociobiology, Biocenter University of Würzburg Würzburg Germany
| | - Markus Thamm
- Behavioral Physiology & Sociobiology, Biocenter University of Würzburg Würzburg Germany
| | - Axel Brockmann
- National Centre for Biological Sciences Tata Institute of Fundamental Research Bangalore India
| | - Ricarda Scheiner
- Behavioral Physiology & Sociobiology, Biocenter University of Würzburg Würzburg Germany
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20
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Adedoja OA, Kehinde T, Samways MJ. Insect-flower interaction networks vary among endemic pollinator taxa over an elevation gradient. PLoS One 2018; 13:e0207453. [PMID: 30496213 PMCID: PMC6264482 DOI: 10.1371/journal.pone.0207453] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 10/31/2018] [Indexed: 01/01/2023] Open
Abstract
Interaction networks are sensitive to elevation gradients through changes in local distribution of interacting partners. Here, we use plant-pollinator interaction network metrics to assess the effect of elevation on flowers and flower-visiting insect assemblages on a sentinel mountain used for monitoring climate change in the flower- and insect-rich Cape Floristic Region. We also use these interaction metrics to explain the effect of environmental factors on the interaction networks. We did this over four vegetation zones <1640m asl, as determined by former botanical studies. Overall, bees were the dominant flower visitors, followed by monkey beetles, and far behind were wasps and flies. The middle elevation zone (650-744 m a.s.l), which is also an ecotone between two distinct botanical zones, had the highest species richness and abundance of interacting plants and insects. Interaction frequency and size of network were also greatest in the middle zone, as were network diversity, generality, and linkage density, while lowest in the peak zone. In sum, there was distinct elevation zoning of flower-visiting insects. The greatest zonal change was between species at the middle compared with peak zone. Large-sized monkey beetles, bees and flies characterized the unique assemblage in the peak zone (1576-1640 m a.s.l.). The insect zonation tracked that of plant assemblages, with air temperature (lapse rate) being the primary driver of bee distribution, with lowest levels in the peak zone. In contrast, beetle distribution was driven mostly by flower assemblages as well as air temperature. In turn, wasp and fly interaction networks were not affected by any of the measured environmental variables. We conclude that increased elevation stress from reduced temperatures, changing abiotic weather conditions (e.g. strong winds at high elevations),and decline in flowering plant composition causes breakdown of interaction networks involving bees and beetles but not that of flies and wasps.
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Affiliation(s)
- Opeyemi A. Adedoja
- Department of Conservation Ecology and Entomology, Stellenbosch University, Stellenbosch, South Africa
- Department of Zoology, Obafemi Awolowo University, Ile-Ife, Nigeria
| | - Temitope Kehinde
- Department of Zoology, Obafemi Awolowo University, Ile-Ife, Nigeria
| | - Michael J. Samways
- Department of Conservation Ecology and Entomology, Stellenbosch University, Stellenbosch, South Africa
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21
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Jachuła J, Konarska A, Denisow B. Micromorphological and histochemical attributes of flowers and floral reward in Linaria vulgaris (Plantaginaceae). PROTOPLASMA 2018; 255:1763-1776. [PMID: 29862424 PMCID: PMC6208823 DOI: 10.1007/s00709-018-1269-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/23/2018] [Indexed: 05/09/2023]
Abstract
The self-incompatible flowers of Linaria vulgaris have developed a range of mechanisms for attraction of insect visitors/pollinators and deterrence of ineffective pollinators and herbivores. These adaptive traits include the flower size and symmetry, the presence of a spur as a "secondary nectar presenter," olfactory (secondary metabolites) and sensual (scent, flower color, nectar guide-contrasting palate) signals, and floral rewards, i.e. pollen and nectar. Histochemical tests revealed that the floral glandular trichomes produced essential oils and flavonoids, and pollen grains contained flavonoids, terpenoids, and steroids, which play a role of olfactory attractants/repellents. The nectary gland is disc-shaped and located at the base of the ovary. Nectar is secreted through numerous modified stomata. Nectar secretion began in the bud stage and lasted to the end of anthesis. The amount of produced nectar depended on the flower age and ranged from 0.21 to 3.95 mg/flower (mean = 1.51 mg). The concentration of sugars in the nectar reached up to 57.0%. Both the nectar amount and sugar concentration demonstrated a significant year and population effect. Pollen production was variable between the years of the study. On average, a single flower of L. vulgaris produced 0.31 mg of pollen. The spectrum of insect visitors in the flowers of L. vulgaris differed significantly between populations. In the urban site, Bombus terrestris and Apis mellifera were the most common visitors, while a considerable number of visits of wasps and syrphid flies were noted in the rural site.
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Affiliation(s)
- Jacek Jachuła
- Department of Botany, University of Life Sciences in Lublin, 15 Akademicka St., 20-950, Lublin, Poland
| | - Agata Konarska
- Department of Botany, University of Life Sciences in Lublin, 15 Akademicka St., 20-950, Lublin, Poland
| | - Bożena Denisow
- Department of Botany, University of Life Sciences in Lublin, 15 Akademicka St., 20-950, Lublin, Poland.
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22
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Basari N, Ramli SN, Mohd Khairi N'AS. Food Reward and Distance Influence the Foraging Pattern of Stingless Bee, Heterotrigona itama. INSECTS 2018; 9:E138. [PMID: 30314344 PMCID: PMC6315735 DOI: 10.3390/insects9040138] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 09/29/2018] [Accepted: 10/06/2018] [Indexed: 11/17/2022]
Abstract
Beekeeping with stingless bee provides new opportunities to improve the incomes of many households in Malaysia through the sale of honey and other bee products. While Heterotrigona itama is one of the most commonly cultured species of stingless bees, its behavior is not very well understood. Hence, we conducted this study to investigate the behavior of H. itama in exploiting food sources by ascertaining the nectar sugar concentration preferred by the bee. We also aimed to determine the preferred distance of food source from the beehive. Our results suggest that H. itama prefers high sugar concentrations of 35% and above, and most of the bees preferred to forage close to their hive to collect food. We discuss how nectar concentration, food distance, and abiotic factors influence the number of bees exploiting food sources and the overall foraging pattern of H. itama.
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Affiliation(s)
- Norasmah Basari
- School of Marine and Environmental Sciences, Universiti Malaysia Terengganu, Kuala Nerus 21030, Terengganu, Malaysia.
- Center of Excellence Apis and Meliponine, Universiti Malaysia Terengganu, Kuala Nerus 21030, Terengganu, Malaysia.
| | - Sarah Najiah Ramli
- School of Marine and Environmental Sciences, Universiti Malaysia Terengganu, Kuala Nerus 21030, Terengganu, Malaysia.
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23
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Kovac H, Käfer H, Stabentheiner A. The energetics and thermoregulation of water collecting honeybees. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2018; 204:783-790. [PMID: 30083885 PMCID: PMC6182700 DOI: 10.1007/s00359-018-1278-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 07/13/2018] [Accepted: 07/23/2018] [Indexed: 11/29/2022]
Abstract
Honeybees need water for different purposes, to maintain the osmotic homeostasis in adults as well as to dilute stored honey and prepare liquid food for the brood. Water is also used for cooling of the hive. Foraging in endothermic insects is energy-intensive and the question arises how much energy bees invest in a resource without any metabolically usable energy. We investigated the energy demand of water collecting bees under natural conditions. The thermoregulation and energetic effort was measured simultaneously in a broad range of experimental ambient temperatures (Ta = 12-40 °C). The thorax temperature as well as the energetic turnover showed a great variability. The mean Tthorax was ranging from ~ 35.7 °C at 12 °C to nearly 42.5 °C at 40 °C. The energy turnover calculated from CO2-release was highest at a Ta of 20 °C with about 60 mW and lowest at 40 °C with about 22 mW per bee. The total costs during collection decreased from 10.4 J at 12 °C to 0.5 J at 40 °C. The energetic effort of the water collectors was comparable with that of 0.5 M sucrose foraging bees. Our investigation strongly supports the hypothesis that the bees' motivational status determines the energetic performance during foraging.
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Affiliation(s)
- Helmut Kovac
- Institute of Biology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Helmut Käfer
- Institute of Biology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Anton Stabentheiner
- Institute of Biology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
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24
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Silva FA, Guirgis A, Thornburg R. Nectar Analysis Throughout the Genus Nicotiana Suggests Conserved Mechanisms of Nectar Production and Biochemical Action. FRONTIERS IN PLANT SCIENCE 2018; 9:1100. [PMID: 30105042 PMCID: PMC6077755 DOI: 10.3389/fpls.2018.01100] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 07/09/2018] [Indexed: 05/30/2023]
Abstract
We have evaluated the floral nectars of nine species from different sections of the genus Nicotiana. These nine species effectively cover the genus. We found that the nectary glands from these different species showed similar developmental regulation with swelling of nectaries during the first half of development and a distinct color change in the nectary gland as development approaches anthesis. When we examined the composition of the nectar from these nine different species we found that they were similar in content. Carbohydrate compositions of these various nectars varied between these species with N. bonariensis showing the highest and N. sylvestris lowest level of sugars. Based upon the amount of carbohydrates, the nectars fell into two groups. We found that hydrogen peroxide accumulated in the nectars of each of these species. While all species showed the presence of hydrogen peroxide in nectar, the quantitative amounts of hydrogen peroxide which was very high in N. rustica and N. bonariensis, suggesting be a common characteristic in short flower Nicotiana species. We further found that the antioxidant ascorbate accumulated in nectar and β-carotene accumulated in nectaries. β-carotene was most high in nectaries of N. bonariensis. We also examined the presence of proteins in the nectars of these species. The protein profile and quantities varied significantly between species, although all species have showed the presence of proteins in their nectars. We performed a limited proteomic analysis of several proteins from these nectars and determined that each of the five abundant proteins examined were identified as Nectarin 1, Nectarin 3, or Nectarin 5. Thus, based upon the results found in numerous species across the genus Nicotiana, we conclude that the mechanisms identified are similar to those mechanisms found in previous studies on ornamental tobacco nectars. Further, these similarities are remarkably conserved, throughout the genus Nicotiana.
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Affiliation(s)
- Fredy A. Silva
- Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, United States
| | - Adel Guirgis
- Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, United States
- Department of Molecular Biology, Genetic Engineering and Biotechnology Research Institute, University of Sadat City, Sadat City, Egypt
| | - Robert Thornburg
- Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, United States
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Sobhy IS, Baets D, Goelen T, Herrera-Malaver B, Bosmans L, Van den Ende W, Verstrepen KJ, Wäckers F, Jacquemyn H, Lievens B. Sweet Scents: Nectar Specialist Yeasts Enhance Nectar Attraction of a Generalist Aphid Parasitoid Without Affecting Survival. FRONTIERS IN PLANT SCIENCE 2018; 9:1009. [PMID: 30061909 PMCID: PMC6055026 DOI: 10.3389/fpls.2018.01009] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2017] [Accepted: 06/21/2018] [Indexed: 05/29/2023]
Abstract
Floral nectar is commonly inhabited by microorganisms, mostly yeasts and bacteria, which can have a strong impact on nectar chemistry and scent. Yet, little is known about the effects of nectar microbes on the behavior and survival of insects belonging to the third trophic level such as parasitoids. Here, we used five nectar-inhabiting yeast species to test the hypothesis that yeast species that almost solely occur in nectar, and therefore substantially rely on floral visitors for dispersal, produce volatile compounds that enhance insect attraction without compromising insect life history parameters, such as survival. Experiments were performed using two nectar specialist yeasts (Metschnikowia gruessii and M. reukaufii) and three generalist species (Aureobasidium pullulans, Hanseniaspora uvarum, and Sporobolomyces roseus). Saccharomyces cerevisiae was included as a reference yeast. We compared olfactory responses of the generalist aphid parasitoid Aphidius ervi (Haliday) (Hymenoptera: Braconidae) when exposed to these microorganisms inoculated in synthetic nectar. Nectar-inhabiting yeasts had a significant impact on nectar chemistry and produced distinct volatile blends, some of which were attractive, while others were neutral or repellent. Among the different yeast species tested, the nectar specialists M. gruessii and M. reukaufii were the only species that produced a highly attractive nectar to parasitoid females, which simultaneously had no adverse effects on longevity and survival of adults. By contrast, parasitoids that fed on nectars fermented with the reference strain, A. pullulans, H. uvarum or S. roseus showed shortest longevity and lowest survival. Additionally, nectars fermented by A. pullulans or S. roseus were consumed significantly less, suggesting a lack of important nutrients or undesirable changes in the nectar chemical profiles. Altogether our results indicate that nectar-inhabiting yeasts play an important, but so far largely overlooked, role in plant-insect interactions by modulating the chemical composition of nectar, and may have important ecological consequences for plant pollination and biological control of herbivorous insects.
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Affiliation(s)
- Islam S. Sobhy
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, KU Leuven, Sint-Katelijne Waver, Belgium
- Department of Plant Protection, Faculty of Agriculture, Suez Canal University, Ismailia, Egypt
| | - Dieter Baets
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, KU Leuven, Sint-Katelijne Waver, Belgium
| | - Tim Goelen
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, KU Leuven, Sint-Katelijne Waver, Belgium
| | - Beatriz Herrera-Malaver
- VIB Lab for Systems Biology and Centre of Microbial and Plant Genetics Lab for Genetics and Genomics, Department of Microbial and Molecular Systems, KU Leuven, Leuven, Belgium
| | - Lien Bosmans
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, KU Leuven, Sint-Katelijne Waver, Belgium
| | - Wim Van den Ende
- Laboratory of Molecular Plant Biology, Biology Department, KU Leuven, Leuven, Belgium
| | - Kevin J. Verstrepen
- VIB Lab for Systems Biology and Centre of Microbial and Plant Genetics Lab for Genetics and Genomics, Department of Microbial and Molecular Systems, KU Leuven, Leuven, Belgium
| | - Felix Wäckers
- Biobest, Westerlo, Belgium
- Lancaster Environment Centre, Lancaster University, Lancaster, United Kingdom
| | - Hans Jacquemyn
- Laboratory of Plant Conversation and Population Biology, Biology Department, KU Leuven, Leuven, Belgium
| | - Bart Lievens
- Laboratory for Process Microbial Ecology and Bioinspirational Management, Department of Microbial and Molecular Systems, KU Leuven, Sint-Katelijne Waver, Belgium
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Hassan AM, Giovanetti M, Raweh HS, Owayss AA, Ansari MJ, Nuru A, Radloff SE, Alqarni AS. Nectar secretion dynamics of Ziziphus nummularia: A melliferous species of dry land ecosystems. Saudi J Biol Sci 2017; 24:1470-1474. [PMID: 30174491 PMCID: PMC6114115 DOI: 10.1016/j.sjbs.2017.01.059] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 01/03/2017] [Accepted: 01/25/2017] [Indexed: 12/03/2022] Open
Abstract
Nectar is used as raw material for the production of honey and as significant reward in the relationship between bees and plants during pollination. Therefore, it is important to investigate its abundance, dynamics and associated governing factors. Weather conditions are known to influence nectar production, and predicted climate changes may be responsible for future declining in total yield from beekeeping activities. We investigated nectar production as total soluble solids (TSS) of well-known species for honey production, Ziziphus nummularia in a hot-arid environment of Saudi Arabia. Data on nectar samples from bagged flowers of different stages during two blooming seasons, 2013 and 2015 were collected on weekly bases, and the data were correlated with weather conditions (temperature, relative humidity, and wind). A significant difference in TSS amount has been obtained, with 1-day old flowers displaying the higher content. TSS production was varied along the different day intervals, for both years, with a peak of production in the afternoon. In our results, nectar production was not correlated to temperature and wind, but was significantly negatively correlated with relative humidity. According to the current and future weather forecasting conditions, understanding of the relationship between weather conditions and nectar availability turned out to be important predictive information that may be interpreted into an economic projection of incomes from beekeeping activities.
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Affiliation(s)
- Awad M.A. Hassan
- Department of Plant Protection, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia
- Department of Plant Protection, Faculty of Agriculture, South Valley University, Egypt
| | | | - Hael S.A. Raweh
- Department of Plant Protection, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Ayman A. Owayss
- Department of Plant Protection, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Mohammad Javed Ansari
- Department of Plant Protection, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia
- Bee Research Chair, Department of Plant Protection, College of Food and Agriculture Sciences, King Saud University, Riyadh, KSA
| | - Adgaba Nuru
- Department of Plant Protection, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia
- Bee Research Chair, Department of Plant Protection, College of Food and Agriculture Sciences, King Saud University, Riyadh, KSA
| | - Sarah E. Radloff
- Department of Statistics, Rhodes University, Grahamstown, South Africa
| | - Abdulaziz S. Alqarni
- Department of Plant Protection, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia
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Knopper LD, Dan T, Reisig DD, Johnson JD, Bowers LM. Sugar concentration in nectar: a quantitative metric of crop attractiveness for refined pollinator risk assessments. PEST MANAGEMENT SCIENCE 2016; 72:1807-12. [PMID: 27197566 PMCID: PMC5094517 DOI: 10.1002/ps.4321] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 05/09/2016] [Accepted: 05/17/2016] [Indexed: 05/21/2023]
Abstract
Those involved with pollinator risk assessment know that agricultural crops vary in attractiveness to bees. Intuitively, this means that exposure to agricultural pesticides is likely greatest for attractive plants and lowest for unattractive plants. While crop attractiveness in the risk assessment process has been qualitatively remarked on by some authorities, absent is direction on how to refine the process with quantitative metrics of attractiveness. At a high level, attractiveness of crops to bees appears to depend on several key variables, including but not limited to: floral, olfactory, visual and tactile cues; seasonal availability; physical and behavioral characteristics of the bee; plant and nectar rewards. Notwithstanding the complexities and interactions among these variables, sugar content in nectar stands out as a suitable quantitative metric by which to refine pollinator risk assessments for attractiveness. Provided herein is a proposed way to use sugar nectar concentration to adjust the exposure parameter (with what is called a crop attractiveness factor) in the calculation of risk quotients in order to derive crop-specific tier I assessments. This Perspective is meant to invite discussion on incorporating such changes in the risk assessment process. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
| | - Tereza Dan
- Stantec Consulting Ltd, Waterloo, Ontario, Canada
| | - Dominic D Reisig
- Department of Entomology, North Carolina State University, Vernon G James Research and Extension Center, Plymouth, NC, USA
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Shackleton K, Balfour NJ, Al Toufailia H, Gaioski R, de Matos Barbosa M, Silva CADS, Bento JMS, Alves DA, Ratnieks FLW. Quality versus quantity: Foraging decisions in the honeybee ( Apis mellifera scutellata) feeding on wildflower nectar and fruit juice. Ecol Evol 2016; 6:7156-7165. [PMID: 28725389 PMCID: PMC5513216 DOI: 10.1002/ece3.2478] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 08/15/2016] [Accepted: 08/18/2016] [Indexed: 01/09/2023] Open
Abstract
Foraging animals must often decide among resources which vary in quality and quantity. Nectar is a resource that exists along a continuum of quality in terms of sugar concentration and is the primary energy source for bees. Alternative sugar sources exist, including fruit juice, which generally has lower energetic value than nectar. We observed many honeybees (Apis mellifera scutellata) foraging on juice from fallen guava (Psidium guajava) fruit near others foraging on nectar. To investigate whether fruit and nectar offered contrasting benefits of quality and quantity, we compared honeybee foraging performance on P. guajava fruit versus two wildflowers growing within 50 m, Richardia brasiliensis and Tridax procumbens. Bees gained weight significantly faster on fruit, 2.72 mg/min, than on either flower (0.17 and 0.12 mg/min, respectively). However, the crop sugar concentration of fruit foragers was significantly lower than for either flower (12.4% vs. 37.0% and 22.7%, respectively). Fruit foragers also spent the most time handling and the least time flying, suggesting that fruit juice was energetically inexpensive to collect. We interpret honeybee foraging decisions in the context of existing foraging models and consider how nest-patch distance may be a key factor for central place foragers choosing between resources of contrasting quality and quantity. We also discuss how dilute solutions, such as fruit juice, can help maintain colony sugar-water balance. These results show the benefits of feeding on resources with contrasting quality and quantity and that even low-quality resources have value.
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Affiliation(s)
- Kyle Shackleton
- Laboratory of Apiculture and Social InsectsSchool of Life SciencesUniversity of SussexBrightonUK
| | - Nicholas J. Balfour
- Laboratory of Apiculture and Social InsectsSchool of Life SciencesUniversity of SussexBrightonUK
| | - Hasan Al Toufailia
- Laboratory of Apiculture and Social InsectsSchool of Life SciencesUniversity of SussexBrightonUK
| | - Roberto Gaioski
- Departamento de Entomologia e AcarologiaEscola Superior de Agricultura “Luiz de Queiroz”Universidade de São PauloPiracicabaSão PauloBrazil
| | - Marcela de Matos Barbosa
- Departamento de Entomologia e AcarologiaEscola Superior de Agricultura “Luiz de Queiroz”Universidade de São PauloPiracicabaSão PauloBrazil
- Departamento de BiologiaFaculdade de FilosofiaCiências e Letras de Ribeirão PretoUniversidade de São PauloRibeirão PretoSão PauloBrazil
| | - Carina A. de S. Silva
- Departamento de Entomologia e AcarologiaEscola Superior de Agricultura “Luiz de Queiroz”Universidade de São PauloPiracicabaSão PauloBrazil
| | - José M. S. Bento
- Departamento de Entomologia e AcarologiaEscola Superior de Agricultura “Luiz de Queiroz”Universidade de São PauloPiracicabaSão PauloBrazil
| | - Denise A. Alves
- Departamento de Entomologia e AcarologiaEscola Superior de Agricultura “Luiz de Queiroz”Universidade de São PauloPiracicabaSão PauloBrazil
| | - Francis L. W. Ratnieks
- Laboratory of Apiculture and Social InsectsSchool of Life SciencesUniversity of SussexBrightonUK
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Honeybee economics: optimisation of foraging in a variable world. Sci Rep 2016; 6:28339. [PMID: 27320240 PMCID: PMC4913264 DOI: 10.1038/srep28339] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 06/01/2016] [Indexed: 12/02/2022] Open
Abstract
In honeybees fast and efficient exploitation of nectar and pollen sources is achieved by persistent endothermy throughout the foraging cycle, which means extremely high energy costs. The need for food promotes maximisation of the intake rate, and the high costs call for energetic optimisation. Experiments on how honeybees resolve this conflict have to consider that foraging takes place in a variable environment concerning microclimate and food quality and availability. Here we report, in simultaneous measurements of energy costs, gains, and intake rate and efficiency, how honeybee foragers manage this challenge in their highly variable environment. If possible, during unlimited sucrose flow, they follow an ‘investment-guided’ (‘time is honey’) economic strategy promising increased returns. They maximise net intake rate by investing both own heat production and solar heat to increase body temperature to a level which guarantees a high suction velocity. They switch to an ‘economizing’ (‘save the honey’) optimisation of energetic efficiency if the intake rate is restricted by the food source when an increased body temperature would not guarantee a high intake rate. With this flexible and graded change between economic strategies honeybees can do both maximise colony intake rate and optimise foraging efficiency in reaction to environmental variation.
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Individual honey bee (Apis cerana) foragers adjust their fuel load to match variability in forage reward. Sci Rep 2015; 5:16418. [PMID: 26549746 PMCID: PMC4637910 DOI: 10.1038/srep16418] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 10/05/2015] [Indexed: 11/25/2022] Open
Abstract
Animals may adjust their behavior according to their perception of risk. Here we show that free-flying honey bee (Apis cerana) foragers mitigate the risk of starvation in the field when foraging on a food source that offers variable rewards by carrying more ‘fuel’ food on their outward journey. We trained foragers to a feeder located 1.2 km from each of four colonies. On average foragers carried 12.7% greater volume of fuel, equivalent to 30.2% more glucose when foraging on a variable source (a random sequence of 0.5, 1.5 and 2.5 M sucrose solution, average sucrose content 1.5 M) than when forging on a consistent source (constant 1.5 M sucrose solution). Our findings complement an earlier study that showed that foragers decrease their fuel load as they become more familiar with a foraging place. We suggest that honey bee foragers are risk sensitive, and carry more fuel to minimize the risk of starvation in the field when a foraging trip is perceived as being risky, either because the forager is unfamiliar with the foraging site, or because the forage available at a familiar site offers variable rewards.
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Giovanetti M, Mariotti Lippi M, Foggi B, Giuliani C. Exploitation of the invasive Acacia pycnantha pollen and nectar resources by the native bee Apis mellifera. Ecol Res 2015. [DOI: 10.1007/s11284-015-1308-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Energetic optimisation of foraging honeybees: flexible change of strategies in response to environmental challenges. PLoS One 2014; 9:e105432. [PMID: 25162211 PMCID: PMC4146532 DOI: 10.1371/journal.pone.0105432] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 07/18/2014] [Indexed: 11/19/2022] Open
Abstract
Heterothermic insects like honeybees, foraging in a variable environment, face the challenge of keeping their body temperature high to enable immediate flight and to promote fast exploitation of resources. Because of their small size they have to cope with an enormous heat loss and, therefore, high costs of thermoregulation. This calls for energetic optimisation which may be achieved by different strategies. An ‘economizing’ strategy would be to reduce energetic investment whenever possible, for example by using external heat from the sun for thermoregulation. An ‘investment-guided’ strategy, by contrast, would be to invest additional heat production or external heat gain to optimize physiological parameters like body temperature which promise increased energetic returns. Here we show how honeybees balance these strategies in response to changes of their local microclimate. In a novel approach of simultaneous measurement of respiration and body temperature foragers displayed a flexible strategy of thermoregulatory and energetic management. While foraging in shade on an artificial flower they did not save energy with increasing ambient temperature as expected but acted according to an ‘investment-guided’ strategy, keeping the energy turnover at a high level (∼56–69 mW). This increased thorax temperature and speeded up foraging as ambient temperature increased. Solar heat was invested to increase thorax temperature at low ambient temperature (‘investment-guided’ strategy) but to save energy at high temperature (‘economizing’ strategy), leading to energy savings per stay of ∼18–76% in sunshine. This flexible economic strategy minimized costs of foraging, and optimized energetic efficiency in response to broad variation of environmental conditions.
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Gherman BI, Denner A, Bobiş O, Dezmirean DS, Mărghitaş LA, Schlüns H, Moritz RFA, Erler S. Pathogen-associated self-medication behavior in the honeybee Apis mellifera. Behav Ecol Sociobiol 2014. [DOI: 10.1007/s00265-014-1786-8] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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