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Shrestha M, Hlawatsch E, Pepe H, Sander LM, Schreier D, Schuchardt M, von Heßberg A, Jentsch A. Flower reflectance and floral traits data from Ökologisch-Botanischer Garten (OBG), Germany. Data Brief 2024; 54:110512. [PMID: 38799715 PMCID: PMC11127523 DOI: 10.1016/j.dib.2024.110512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 05/03/2024] [Accepted: 05/06/2024] [Indexed: 05/29/2024] Open
Abstract
Not all colours are perceived and interpreted equally. The electromagnetic spectrum is perceived differently by the distinct visual systems of animal species, resulting in differences in each species' colour perception. Given the diverse colours found in flowering plants, it is interesting to consider the colour perception of insects and the co-evolution of flowering plants to attract pollinators. Here, we considered the differences between human visual systems and that of bees and flies-the two largest insect pollinator groups. We collected flower reflectance spectral data of 73 species across seven human-perceived colours using a spectrophotometer. Minimum of 3 different flowers were used to measure the reflectance properties of flower colours. The raw data can be used to visualize the different animals' visual systems i.e. it can be processed and translated into known photoreceptors of human, bee, and fly visual systems. Overall, our data will help to compare how different animals see flower colours in the natural world and will also highlight the importance of understanding the interspecific communication in plant-pollinator communities. Thus, our data will assist scientists in the future to recognize the floral colour evolution in angiosperms.
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Affiliation(s)
- Mani Shrestha
- Department of Disturbance Ecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, 95447 Bayreuth, Germany
- Department of Life Science, National Taiwan University, Taipei, Taiwan
| | - Evelyn Hlawatsch
- Faculty of Biology, Chemistry and Earth Sciences, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Hannah Pepe
- Faculty of Biology, Chemistry and Earth Sciences, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Louis-Marvin Sander
- Faculty of Biology, Chemistry and Earth Sciences, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Dietmar Schreier
- Faculty of Biology, Chemistry and Earth Sciences, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Max Schuchardt
- Department of Disturbance Ecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, 95447 Bayreuth, Germany
| | - Andreas von Heßberg
- Department of Disturbance Ecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, 95447 Bayreuth, Germany
| | - Anke Jentsch
- Department of Disturbance Ecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, 95447 Bayreuth, Germany
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2
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Shrestha M, Tai KC, Dyer AG, Garcia JE, Yang EC, Jentsch A, Wang CN. Flower colour and size-signals vary with altitude and resulting climate on the tropical-subtropical islands of Taiwan. FRONTIERS IN PLANT SCIENCE 2024; 15:1304849. [PMID: 38362451 PMCID: PMC10867191 DOI: 10.3389/fpls.2024.1304849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 01/09/2024] [Indexed: 02/17/2024]
Abstract
The diversity of flower colours in nature provides quantifiable evidence for how visitations by colour sensing insect pollinators can drive the evolution of angiosperm visual signalling. Recent research shows that both biotic and abiotic factors may influence flower signalling, and that harsher climate conditions may also promote salient signalling to entice scarcer pollinators to visit. In parallel, a more sophisticated appreciation of the visual task foragers face reveals that bees have a complex visual system that uses achromatic vision when moving fast, whilst colour vision requires slower, more careful inspection of targets. Spectra of 714 native flowering species across Taiwan from sea level to mountainous regions 3,300 m above sea level (a.s.l.) were measured. We modelled how the visual system of key bee pollinators process signals, including flower size. By using phylogenetically informed analyses, we observed that at lower altitudes including foothills and submontane landscapes, there is a significant relationship between colour contrast and achromatic signals. Overall, the frequency of flowers with high colour contrast increases with altitude, whilst flower size decreases. The evidence that flower colour signaling becomes increasingly salient in higher altitude conditions supports that abiotic factors influence pollinator foraging in a way that directly influences how flowering plants need to advertise.
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Affiliation(s)
- Mani Shrestha
- Department of Disturbance Ecology and Vegetation Dynamics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
- Department of Life Science, National Taiwan University, Taipei, Taiwan
| | - King-Chun Tai
- Department of Life Science, National Taiwan University, Taipei, Taiwan
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, Taiwan
| | - Adrian G. Dyer
- Department of Physiology, Monash University, Clayton, VIC, Australia
| | - Jair E. Garcia
- Melbourne Data Analytics Platform, The University of Melbourne, Melbourne, VIC, Australia
| | - En-Cheng Yang
- Department of Entomology, National Taiwan University, Taipei, Taiwan
| | - Anke Jentsch
- Department of Disturbance Ecology and Vegetation Dynamics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Chun-Neng Wang
- Department of Life Science, National Taiwan University, Taipei, Taiwan
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, Taiwan
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3
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Dorin A, Shrestha M, Garcia JE, Burd M, Dyer AG. Ancient insect vision tuned for flight among rocks and plants underpins natural flower colour diversity. Proc Biol Sci 2023; 290:20232018. [PMID: 38113941 PMCID: PMC10730291 DOI: 10.1098/rspb.2023.2018] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 11/27/2023] [Indexed: 12/21/2023] Open
Abstract
Understanding the origins of flower colour signalling to pollinators is fundamental to evolutionary biology and ecology. Flower colour evolves under pressure from visual systems of pollinators, like birds and insects, to establish global signatures among flowers with similar pollinators. However, an understanding of the ancient origins of this relationship remains elusive. Here, we employ computer simulations to generate artificial flower backgrounds assembled from real material sample spectra of rocks, leaves and dead plant materials, against which to test flowers' visibility to birds and bees. Our results indicate how flower colours differ from their backgrounds in strength, and the distributions of salient reflectance features when perceived by these key pollinators, to reveal the possible origins of their colours. Since Hymenopteran visual perception evolved before flowers, the terrestrial chromatic context for its evolution to facilitate flight and orientation consisted of rocks, leaves, sticks and bark. Flowers exploited these pre-evolved visual capacities of their visitors, in response evolving chromatic features to signal to bees, and differently to birds, against a backdrop of other natural materials. Consequently, it appears that today's flower colours may be an evolutionary response to the vision of diurnal pollinators navigating their world millennia prior to the first flowers.
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Affiliation(s)
- Alan Dorin
- Department of Data Science and AI, Faculty of Information Technology, Monash University, Clayton 3800, Australia
| | - Mani Shrestha
- Department of Disturbance Ecology, Bayreuth Center of Ecology and Environmental Research, University of Bayreuth, 95447 Bayreuth, Germany
| | - Jair E. Garcia
- Melbourne Data Analytics Platform, The University of Melbourne, Melbourne Connect, Parkville 3052, Australia
| | - Martin Burd
- Department of Biology, Indiana University Herbarium, Indiana University, Bloomington, IN 47405, USA
| | - Adrian G. Dyer
- Department of Physiology, Faculty of Medicine, Monash University, Clayton 3800, Australia
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4
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Garcia JE, Hannah L, Shrestha M, Burd M, Dyer AG. Fly pollination drives convergence of flower coloration. THE NEW PHYTOLOGIST 2022; 233:52-61. [PMID: 34460949 DOI: 10.1111/nph.17696] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 08/18/2021] [Indexed: 06/13/2023]
Abstract
Plant-pollinator interactions provide a natural experiment in signal evolution. Flowers are known to have evolved colour signals that maximise their ease of detection by the visual systems of important pollinators such as bees. Whilst most angiosperms are bee pollinated, our understanding on how the second largest group of pollinating insects, flies, may influence flower colour evolution is limited to the use of categorical models of colour discrimination that do not reflect the small colour differences commonly observed between and within flower species. Here we show by comparing flower signals that occur in different environments including total absence of bees, a mixture of bee and fly pollination within one plant family (Orchidaceae) from a single community, and typical flowers from a broad taxonomic sampling of the same geographic region, that perceptually different colours, empirically measured, do evolve in response to different types of insect pollinators. We show evidence of both convergence among fly-pollinated floral colours but also of divergence and displacement of colour signals in the absence of bee pollinators. Our findings give an insight into how both ecological and agricultural systems may be affected by changes in pollinator distributions around the world.
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Affiliation(s)
- Jair E Garcia
- Bio-Inspired Digital Sensing Laboratory, School of Media and Communication, RMIT University, Melbourne, Vic., 3000, Australia
| | - Lea Hannah
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2750, Australia
| | - Mani Shrestha
- Department of Disturbance Ecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, 95447, Germany
- School of Information Technology, Monash University, Clayton, Vic., 3168, Australia
| | - Martin Burd
- School of Biological Sciences, Monash University, Clayton, Vic., 3168, Australia
| | - Adrian G Dyer
- Bio-Inspired Digital Sensing Laboratory, School of Media and Communication, RMIT University, Melbourne, Vic., 3000, Australia
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5
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Koethe S, Reinartz L, Heard TA, Garcia JE, Dyer AG, Lunau K. Comparative psychophysics of Western honey bee (Apis mellifera) and stingless bee (Tetragonula carbonaria) colour purity and intensity perception. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2022; 208:641-652. [PMID: 36269403 PMCID: PMC9734212 DOI: 10.1007/s00359-022-01581-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 09/13/2022] [Accepted: 09/28/2022] [Indexed: 12/14/2022]
Abstract
Bees play a vital role as pollinators worldwide and have influenced how flower colour signals have evolved. The Western honey bee, Apis mellifera (Apini), and the Buff-tailed bumble bee, Bombus terrestris (Bombini) are well-studied model species with regard to their sensory physiology and pollination capacity, although currently far less is known about stingless bees (Meliponini) that are common in pantropical regions. We conducted comparative experiments with two highly eusocial bee species, the Western honey bee, A. mellifera, and the Australian stingless bee, Tetragonula carbonaria, to understand their colour preferences considering fine-scaled stimuli specifically designed for testing bee colour vision. We employed stimuli made of pigment powders to allow manipulation of single colour parameters including spectral purity (saturation) or colour intensity (brightness) of a blue colour (hue) for which both species have previously shown innate preferences. Both A. mellifera and T. carbonaria demonstrated a significant preference for spectrally purer colour stimuli, although this preference is more pronounced in honey bees than in stingless bees. When all other colour cues were tightly controlled, honey bees receiving absolute conditioning demonstrated a capacity to learn a high-intensity stimulus significant from chance expectation demonstrating some capacity of plasticity for this dimension of colour perception. However, honey bees failed to learn low-intensity stimuli, and T. carbonaria was insensitive to stimulus intensity as a cue. These comparative findings suggest that there may be some common roots underpinning colour perception in bee pollinators and how they interact with flowers, although species-specific differences do exist.
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Affiliation(s)
- Sebastian Koethe
- Institute of Sensory Ecology, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany
| | - Lara Reinartz
- Institute of Sensory Ecology, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany
| | | | - Jair E. Garcia
- School of Media and Communication, RMIT University, Building 5.2.36, City Campus, GPO Box 2476, Melbourne, VIC 3001 Australia
| | - Adrian G. Dyer
- School of Media and Communication, RMIT University, Building 5.2.36, City Campus, GPO Box 2476, Melbourne, VIC 3001 Australia ,Department of Physiology, Monash University, Melbourne, 3800 Australia ,Institute of Developmental Biology and Neurobiology, Johannes Gutenberg Universität, Mainz, Germany
| | - Klaus Lunau
- Institute of Sensory Ecology, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany
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6
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Tunes P, Camargo MGG, Guimarães E. Floral UV Features of Plant Species From a Neotropical Savanna. FRONTIERS IN PLANT SCIENCE 2021; 12:618028. [PMID: 34025689 PMCID: PMC8137824 DOI: 10.3389/fpls.2021.618028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 04/07/2021] [Indexed: 06/12/2023]
Abstract
Despite the wide interest in flower colours, only after the end of the nineteenth-century studies started to comprise floral UV reflection, which is invisible to humans but visible to the major groups of pollinators. Many flowers and inflorescences display colour patterns, an important signal for pollinators, promoted by the presence of at least two different colours within flowers or inflorescences, including colours in the UV waveband. For Neotropical savanna plant species, we characterised floral UV features using UV-photography and reflectance measurements. We tested (i) whether floral UV features were constrained by their shared ancestry, (ii) whether floral UV features were associated with pollinators, and (iii) whether floral UV features were associated with floral traits mediating these interactions, including floral resource, type of attraction unit and presence/absence of non-UV colour patterns. Of 80 plant species, ca. 70% were UV-patternless, most of them UV-absorbing. Approximately 30% presented one of three types of UV-patterns: bullseye, contrasting corolla markings oriented toward floral resources or contrasting reproductive structures, which were all considered as floral guides. Floral UV features were phylogenetically constrained and were associated with pollinators, floral resources and attraction unit, but not with non-UV colour patterns. UV-patternless flowers were associated with most of the pollination systems, while UV-patterned flowers were mainly associated with bee-pollination. UV-absorbing flowers comprised the only category with hawkmoth- and butterfly-pollinated flowers, and a high percentage of hummingbird-pollinated species. Nocturnal pollinated species were also commonly UV-absorbing, except for one UV-reflecting bat-pollinated species and one beetle-pollinated species with UV-reflecting stigmas. All types of floral UV features were associated with nectar; however, flowers with contrasting reproductive structures were mainly associated with pollen. There was an association between UV-absorbing species and the presence of inflorescences and intermediate attraction units. Our results evince that phylogenetic relatedness can constraint floral UV features' diversification, but combinations of evolutionary and ecological processes may be expected in this scenario.
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Affiliation(s)
- Priscila Tunes
- Laboratory of Ecology and Evolution of Plant-Animal Interactions, Postgraduate Program in Biological Sciences (Botany), Institute of Biosciences, São Paulo State University, Botucatu, Brazil
| | | | - Elza Guimarães
- Laboratory of Ecology and Evolution of Plant-Animal Interactions, Institute of Biosciences, São Paulo State University, Botucatu, Brazil
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7
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Martins AE, Camargo MGG, Morellato LPC. Flowering Phenology and the Influence of Seasonality in Flower Conspicuousness for Bees. FRONTIERS IN PLANT SCIENCE 2021; 11:594538. [PMID: 33664750 PMCID: PMC7921784 DOI: 10.3389/fpls.2020.594538] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 12/28/2020] [Indexed: 05/28/2023]
Abstract
Flowering patterns are crucial to understand the dynamics of plant reproduction and resource availability for pollinators. Seasonal climate constrains flower and leaf phenology, where leaf and flower colors likely differ between seasons. Color is the main floral trait attracting pollinators; however, seasonal changes in the leaf-background coloration affect the perception of flower color contrasts by pollinators. For a seasonally dry woody cerrado community (Brazilian savanna) mainly pollinated by bees, we verified whether seasonality affects flower color diversity over time and if flower color contrasts of bee-pollinated species differ between seasons due to changes in the leaf-background coloration. For 140 species, we classified flower colors based on human-color vision, and for 99 species, we classified flower colors based on bee-color vision (spectral measurements). We described the community's flowering pattern according to the flower colors using a unique 11 years phenological database. For the 43 bee-pollinated species in which reflectance data were also available, we compared flower color diversity and contrasts against the background between seasons, considering the background coloration of each season. Flowering was markedly seasonal, peaking at the end of the dry season (September), when the highest diversity of flower colors was observed. Yellow flowers were observed all year round, whereas white flowers were seasonal, peaking during the dry season, and pink flowers predominated in the wet season, peaking in March. Bee-bluegreen flowers peaked between September and October. Flowers from the wet and dry seasons were similarly conspicuous against their corresponding background. Regardless of flowering season, the yellowish background of the dry season promoted higher flower color contrast for all flower species, whereas the greener background of the wet season promoted a higher green contrast. Temporal patterns of flower colors and color contrasts were related to the cerrado seasonality, but also to bee's activity, visual system, and behavior. Background coloration affected flower contrasts, favoring flower conspicuousness to bees according to the season. Thus, our results provide new insights regarding the temporal patterns of plant-pollinator interactions.
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Affiliation(s)
- Amanda Eburneo Martins
- Phenology Laboratory, Department of Biodiversity, Biosciences Institute, São Paulo State University (UNESP), Rio Claro, Brazil
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8
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Dyer AG, Jentsch A, Burd M, Garcia JE, Giejsztowt J, Camargo MGG, Tjørve E, Tjørve KMC, White P, Shrestha M. Fragmentary Blue: Resolving the Rarity Paradox in Flower Colors. FRONTIERS IN PLANT SCIENCE 2021; 11:618203. [PMID: 33552110 PMCID: PMC7859648 DOI: 10.3389/fpls.2020.618203] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 12/17/2020] [Indexed: 05/05/2023]
Abstract
Blue is a favored color of many humans. While blue skies and oceans are a common visual experience, this color is less frequently observed in flowers. We first review how blue has been important in human culture, and thus how our perception of blue has likely influenced the way of scientifically evaluating signals produced in nature, including approaches as disparate as Goethe's Farbenlehre, Linneaus' plant taxonomy, and current studies of plant-pollinator networks. We discuss the fact that most animals, however, have different vision to humans; for example, bee pollinators have trichromatic vision based on UV-, Blue-, and Green-sensitive photoreceptors with innate preferences for predominantly short-wavelength reflecting colors, including what we perceive as blue. The subsequent evolution of blue flowers may be driven by increased competition for pollinators, both because of a harsher environment (as at high altitude) or from high diversity and density of flowering plants (as in nutrient-rich meadows). The adaptive value of blue flowers should also be reinforced by nutrient richness or other factors, abiotic and biotic, that may reduce extra costs of blue-pigments synthesis. We thus provide new perspectives emphasizing that, while humans view blue as a less frequently evolved color in nature, to understand signaling, it is essential to employ models of biologically relevant observers. By doing so, we conclude that short wavelength reflecting blue flowers are indeed frequent in nature when considering the color vision and preferences of bees.
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Affiliation(s)
- Adrian G. Dyer
- School of Media and Communication, RMIT University, Melbourne, VIC, Australia
| | - Anke Jentsch
- Department of Disturbance Ecology, Bayreuth Center for Ecology and Environmental Research, University of Bayreuth, Bayreuth, Germany
| | - Martin Burd
- School of Biological Sciences, Monash University, Melbourne, VIC, Australia
| | - Jair E. Garcia
- School of Media and Communication, RMIT University, Melbourne, VIC, Australia
| | - Justyna Giejsztowt
- Department of Disturbance Ecology, Bayreuth Center for Ecology and Environmental Research, University of Bayreuth, Bayreuth, Germany
| | - Maria G. G. Camargo
- Phenology Lab, Biosciences Institute, Department of Biodiversity, UNESP – São Paulo State University, São Paulo, Brazil
| | - Even Tjørve
- Inland Norway University of Applied Sciences, Lillehammer, Norway
| | | | - Peter White
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Mani Shrestha
- School of Media and Communication, RMIT University, Melbourne, VIC, Australia
- Faculty of Information Technology, Monash University, Melbourne, VIC, Australia
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9
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Dalrymple RL, Kemp DJ, Flores-Moreno H, Laffan SW, White TE, Hemmings FA, Moles AT. Macroecological patterns in flower colour are shaped by both biotic and abiotic factors. THE NEW PHYTOLOGIST 2020; 228:1972-1985. [PMID: 32533864 DOI: 10.1111/nph.16737] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 05/24/2020] [Indexed: 05/22/2023]
Abstract
There is a wealth of research on the way interactions with pollinators shape flower traits. However, we have much more to learn about influences of the abiotic environment on flower colour. We combine quantitative flower colour data for 339 species from a broad spatial range covering tropical, temperate, arid, montane and coastal environments from 9.25ºS to 43.75ºS with 11 environmental variables to test hypotheses about how macroecological patterns in flower colouration relate to biotic and abiotic conditions. Both biotic community and abiotic conditions are important in explaining variation of flower colour traits on a broad scale. The diversity of pollinating insects and the plant community have the highest predictive power for flower colouration, followed by mean annual precipitation and solar radiation. On average, flower colours are more chromatic where there are fewer pollinators, solar radiation is high, precipitation and net primary production are low, and growing seasons are short, providing support for the hypothesis that higher chromatic contrast of flower colours may be related to stressful conditions. To fully understand the ecology and evolution of flower colour, we should incorporate the broad selective context that plants experience into research, rather than focusing primarily on effects of plant-pollinator interactions.
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Affiliation(s)
- Rhiannon L Dalrymple
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Darrell J Kemp
- Department of Biological Sciences, Faculty of Science and Engineering, Macquarie University, North Ryde, Sydney, NSW, 2109, Australia
| | - Habacuc Flores-Moreno
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St Paul, MN, 55108, USA
| | - Shawn W Laffan
- School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Thomas E White
- School of Life and Environmental Sciences, The University of Sydney, Camperdown, Sydney, NSW, 2109, Australia
| | - Frank A Hemmings
- John T. Waterhouse Herbarium, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Angela T Moles
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia
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10
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Competition and pollen wars: simulations reveal the dynamics of competition mediated through heterospecific pollen transfer by non-flower constant insects. THEOR ECOL-NETH 2020. [DOI: 10.1007/s12080-020-00490-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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11
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Shrestha M, Garcia JE, Burd M, Dyer AG. Australian native flower colours: Does nectar reward drive bee pollinator flower preferences? PLoS One 2020; 15:e0226469. [PMID: 32525873 PMCID: PMC7289428 DOI: 10.1371/journal.pone.0226469] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 05/18/2020] [Indexed: 11/18/2022] Open
Abstract
Colour is an important signal that flowering plants use to attract insect pollinators like bees. Previous research in Germany has shown that nectar volume is higher for flower colours that are innately preferred by European bees, suggesting an important link between colour signals, bee preferences and floral rewards. In Australia, flower colour signals have evolved in parallel to the Northern hemisphere to enable easy discrimination and detection by the phylogenetically ancient trichromatic visual system of bees, and native Australian bees also possess similar innate colour preferences to European bees. We measured 59 spectral signatures from flowers present at two preserved native habitats in South Eastern Australia and tested whether there were any significant differences in the frequency of flowers presenting higher nectar rewards depending upon the colour category of the flower signals, as perceived by bees. We also tested if there was a significant correlation between chromatic contrast and the frequency of flowers presenting higher nectar rewards. For the entire sample, and for subsets excluding species in the Asteraceae and Orchidaceae, we found no significant difference among colour categories in the frequency of high nectar reward. This suggests that whilst such relationships between flower colour signals and nectar volume rewards have been observed at a field site in Germany, the effect is likely to be specific at a community level rather than a broad general principle that has resulted in the common signalling of bee flower colours around the world.
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Affiliation(s)
- Mani Shrestha
- Bio-Inspired Digital Lab (BIDS-Lab), Schools of Media and Communication, RMIT University, Melbourne, Australia
| | - Jair E. Garcia
- Bio-Inspired Digital Lab (BIDS-Lab), Schools of Media and Communication, RMIT University, Melbourne, Australia
| | - Martin Burd
- School of Biological Sciences, Monash University, Melbourne, Australia
| | - Adrian G. Dyer
- Bio-Inspired Digital Lab (BIDS-Lab), Schools of Media and Communication, RMIT University, Melbourne, Australia
- * E-mail:
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12
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Peach K, Liu JW, Klitgaard KN, Mazer SJ. Sex-specific floral attraction traits in a sequentially hermaphroditic species. Ecol Evol 2020; 10:1856-1875. [PMID: 32128121 PMCID: PMC7042773 DOI: 10.1002/ece3.5987] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 12/04/2019] [Accepted: 12/16/2019] [Indexed: 11/10/2022] Open
Abstract
●Many angiosperms are hermaphroditic and produce bisexual flowers in which male (pollen export) and female (stigma receptivity) functions are separated temporally. This sequential hermaphroditism may be associated with variation in flower size, color, or pattern, all of which may influence pollinator attraction. In this study, we describe variation in these traits across discrete functional sex stages within and between 225 greenhouse-grown individuals of Clarkia unguiculata (Onagraceae). In addition, to identify the effects of floral phenotype on pollinator attraction in this species, we examine the effects of these floral traits on pollen receipt in ~180 individuals in an experimental field array.●Petal area, ultraviolet (UV)-absorbing nectar guide area, and blue and green mean petal reflectance differ significantly across the functional sex stages of C. unguiculata. Male- and female-phase flowers display significantly different pollinator attraction traits. Petal and UV nectar guide area increase as flowers progress from male phase to female phase, while blue reflectance and green reflectance peak during anther maturation.●In field arrays of C. unguiculata, female-phase flowers with large UV nectar guides receive more pollen than those with small nectar guides, and female-phase flowers with high mean blue reflectance values are more likely to receive pollen than those with low blue reflectance. Female-phase flowers with green mean reflectance values that differ most from background foliage also receive more pollen than those that are more similar to foliage. These findings indicate that components of flower color and pattern influence pollen receipt, independent of other plant attributes that may covary with floral traits. We discuss these results in the context of hypotheses that have been proposed to explain sex-specific floral attraction traits, and we suggest future research that could improve our understanding of sexual dimorphism in sequentially hermaphroditic species and the evolution of features that promote outcrossing.
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Affiliation(s)
- Kristen Peach
- Department of Ecology, Evolution and Marine BiologyUniversity of California, Santa BarbaraSanta BarbaraCAUSA
| | - Jasen W. Liu
- Department of Ecology, Evolution and Marine BiologyUniversity of California, Santa BarbaraSanta BarbaraCAUSA
| | - Kristen N. Klitgaard
- Department of Ecology, Evolution and Marine BiologyUniversity of California, Santa BarbaraSanta BarbaraCAUSA
| | - Susan J. Mazer
- Department of Ecology, Evolution and Marine BiologyUniversity of California, Santa BarbaraSanta BarbaraCAUSA
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Paudel BR, Burd M, Shrestha M, Dyer AG, Li QJ. Reproductive isolation in alpine gingers: How do coexisting Roscoea (R. purpurea and R. tumjensis) conserve species integrity? Evolution 2019; 72:1840-1850. [PMID: 29992542 DOI: 10.1111/evo.13546] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 06/07/2018] [Indexed: 02/06/2023]
Abstract
Multiple barriers may contribute to reproductive isolation between closely related species. Understanding the relative strength of these barriers can illuminate the ecological factors that currently maintain species integrity and how these factors originally promoted speciation. Two Himalayan alpine gingers, Roscoea purpurea and R. tumjensis, occur sympatrically in central Nepal and have such similar morphology that it is not clear whether or how they maintain a distinct identity. Our quantitative measurements of the components of reproductive isolation show that they are, in fact, completely isolated by a combination of phenological displacement of flowering, earlier for R. tumjensis and later for R. purpurea, and complete fidelity of visitation by different pollinator species, bumblebees for R. tumjensis and a long-tongued fly for R. purpurea. Furthermore, the nectar of R. tumjensis flowers is available to the shorter tongued bumblebees while R. purpurea nectar is less accessible, requiring deep probing from long-tongued flies. Although flowering phenology is a strong current barrier that seemingly obviates any need for pollinator discrimination, this current pattern need not reflect selective forces occurring at the initial divergence of R. tumjensis. There has been considerable pollinator switching during the radiation of the Himalayan Roscoea, and the association of flowering time with type of pollinator in these sympatric species may have originated among the earliest or latest flowering individuals or populations of an ancestor to exploit either bumblebee activity early in the breeding season or long-tongued fly abundance later in the season. These two sympatric Roscoea species add to accumulating evidence of the primacy of prezygotic pollination traits in speciation among angiosperms even in the absence of postzygotic incompatibility.
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Affiliation(s)
- Babu Ram Paudel
- Current Address: Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, 650091, Yunnan, China.,Department of Botany, Prithvi Narayan Campus, Tribhuvan University, Pokhara, Nepal
| | - Martin Burd
- School of Biological Sciences, Monash University, Melbourne, VIC, 3800, Australia
| | - Mani Shrestha
- Faculty of information Technology, Monash University, Melbourne, VIC, 3800, Australia.,School of Media and Communications, RMIT University, Melbourne, VIC, 3001, Australia
| | - Adrian G Dyer
- School of Media and Communications, RMIT University, Melbourne, VIC, 3001, Australia.,Department of Physiology, Monash University, Melbourne, 3800, Australia
| | - Qing-Jun Li
- Current Address: Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, 650091, Yunnan, China
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14
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Shrestha M, Dyer AG, Garcia JE, Burd M. Floral colour structure in two Australian herbaceous communities: it depends on who is looking. ANNALS OF BOTANY 2019; 124:221-232. [PMID: 31008511 PMCID: PMC6758583 DOI: 10.1093/aob/mcz043] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 03/14/2019] [Indexed: 05/03/2023]
Abstract
BACKGROUND AND AIMS Pollinator-mediated interactions between plant species may affect the composition of angiosperm communities. Floral colour signals should play a role in these interactions, but the role will arise from the visual perceptions and behavioural responses of multiple pollinators. Recent advances in the visual sciences can be used to inform our understanding of these perceptions and responses. We outline the application of appropriate visual principles to the analysis of the annual cycle of floral colour structure in two Australian herbaceous communities. METHODS We used spectrographic measurements of petal reflectance to determine the location of flowers in a model of hymenopteran colour vision. These representations of colour perception were then translated to a behaviourally relevant metric of colour differences using empirically calibrated colour discrimination functions for four hymenopteran species. We then analysed the pattern of colour similarity in terms of this metric in samples of co-flowering plants over the course of a year. We used the same method to analyse the annual pattern of phylogenetic relatedness of co-flowering plants in order to compare colour structure and phylogenetic structure. KEY RESULTS Co-flowering communities at any given date seldom had colour assemblages significantly different from random. Non-random structure, both dispersion and clustering, occurred occasionally, but depended on which bee observer is considered. The degree of colour similarity was unrelated to phylogenetic similarity within a co-flowering community. CONCLUSIONS Perceived floral colour structure varied with the sensory capabilities of the observer. The lack of colour structure at most sample dates, particularly the rarity of strong dispersion, suggests that plants do not use chromatic signals primarily to enable bees to discriminate between co-flowering species. It is more likely that colours make plants detectable in a complex landscape.
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Affiliation(s)
- Mani Shrestha
- School of Biological Sciences, Monash University, Melbourne, Australia
- School of Media and Communication, RMIT University, Melbourne, Australia
| | - Adrian G Dyer
- School of Media and Communication, RMIT University, Melbourne, Australia
- Department of Physiology, Monash University, Melbourne, Australia
- For correspondence. E-mail
| | - Jair E Garcia
- School of Media and Communication, RMIT University, Melbourne, Australia
| | - Martin Burd
- School of Biological Sciences, Monash University, Melbourne, Australia
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15
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Garcia JE, Shrestha M, Howard SR, Petersen P, Dyer AG. Signal or cue: the role of structural colors in flower pollination. Curr Zool 2019; 65:467-481. [PMID: 31413719 PMCID: PMC6688579 DOI: 10.1093/cz/zoy096] [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] [Revised: 09/27/2017] [Accepted: 12/11/2018] [Indexed: 11/13/2022] Open
Abstract
Angle dependent colors, such as iridescence, are produced by structures present on flower petals changing their visual appearance. These colors have been proposed to act as signals for plant-insect communication. However, there is a paucity of behavioral data to allow for interpretations of how to classify these colors either as a signal or a cue when considering the natural conditions under which pollination occurs. We sampled flowers from 6 plant species across various viewpoints looking for changes in the visual appearance of the petals. Spectral characteristics were measured with different instruments to simulate both the spectral and spatial characteristics of honeybee's vision. We show the presence of color patches produced by angle dependent effects on the petals and the calyx of various species; however, the appearance of the angle dependent color patches significantly varies with viewpoint and would only be resolved by the insect eye at close distances. Behavior experiments with honeybees revealed that pollinators did not use angle dependent colors to drive behavior when presented with novel flower presentations. Results show that angle dependent colors do not comply with the requirements of a signal for plant-pollinator communication since the information transmitted by these colors would be unreliable for potential, free-flying pollination vectors. We thus classify angle dependent colors produced by micro- and ultra-structures as being a cue (a feature which has not evolved for communication), and observe no evidence supporting claims of these angle dependent colors having evolved as visual signal.
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Affiliation(s)
- Jair E Garcia
- School of Media and Communication, RMIT University, Melbourne, Victoria 3001, Australia
| | - Mani Shrestha
- School of Media and Communication, RMIT University, Melbourne, Victoria 3001, Australia
- Faculty of Information Technology, Monash University, Clayton, Victoria 3800, Australia
| | - Scarlett R Howard
- School of Media and Communication, RMIT University, Melbourne, Victoria 3001, Australia
| | - Phred Petersen
- School of Media and Communication, RMIT University, Melbourne, Victoria 3001, Australia
| | - Adrian G Dyer
- School of Media and Communication, RMIT University, Melbourne, Victoria 3001, Australia
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16
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de Camargo MGG, Lunau K, Batalha MA, Brings S, de Brito VLG, Morellato LPC. How flower colour signals allure bees and hummingbirds: a community-level test of the bee avoidance hypothesis. THE NEW PHYTOLOGIST 2019; 222:1112-1122. [PMID: 30444536 DOI: 10.1111/nph.15594] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 11/08/2018] [Indexed: 05/07/2023]
Abstract
Colour signals are the main floral trait for plant-pollinator communication. Owing to visual specificities, flower visitors exert different selective pressures on flower colour signals of plant communities. Although they evolved to attract pollinators, matching their visual sensitivity and colour preferences, floral signals may also evolve to avoid less efficient pollinators and antagonistic flower visitors. We evaluated evidence for the bee avoidance hypothesis in a Neotropical community pollinated mainly by bees and hummingbirds, the campo rupestre. We analysed flower reflectance spectra, compared colour variables of bee-pollinated flowers (bee-flowers; 244 species) and hummingbird-pollinated flowers (hummingbird-flowers; 39 species), and looked for evidence of bee sensorial exclusion in hummingbird-flowers. Flowers were equally contrasting for hummingbirds. Hummingbird-flowers were less conspicuous to bees, reflecting mainly long wavelengths and avoiding red-blind visitors. Bee-flowers reflected more short wavelengths, were more conspicuous to bees (higher contrasts and spectral purity) than hummingbird-flowers and displayed floral guides more frequently, favouring flower attractiveness, discrimination and handling by bees. Along with no phylogenetic signal, the differences in colour signal strategies between bee- and hummingbird-flowers are the first evidence of the bee avoidance hypothesis at a community level and reinforce the role of pollinators as a selective pressure driving flower colour diversity.
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Affiliation(s)
- Maria Gabriela Gutierrez de Camargo
- Departamento de Botânica, Laboratório de Fenologia, Instituto de Biociências, UNESP-Universidade Estadual Paulista, 13506-900, Rio Claro, São Paulo, Brasil
| | - Klaus Lunau
- Department Biology, Institute of Sensory Ecology, Heinrich-Heine-University Düsseldorf, 40225, Düsseldorf, Germany
| | - Marco Antônio Batalha
- Department of Botany, Federal University of São Carlos, 13565-905, São Carlos, São Paulo, Brazil
| | - Sebastian Brings
- Department Biology, Institute of Sensory Ecology, Heinrich-Heine-University Düsseldorf, 40225, Düsseldorf, Germany
| | | | - Leonor Patrícia Cerdeira Morellato
- Departamento de Botânica, Laboratório de Fenologia, Instituto de Biociências, UNESP-Universidade Estadual Paulista, 13506-900, Rio Claro, São Paulo, Brasil
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17
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Dyer AG, Shrestha M. Assessment of floral colour signals at a community through the eyes of the birds and bees. THE NEW PHYTOLOGIST 2019; 222:648-650. [PMID: 30895650 DOI: 10.1111/nph.15724] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Affiliation(s)
- Adrian G Dyer
- Bio-inspired Digital Sensing (BIDS) Lab, School of Media and Communication, RMIT University, Melbourne, VIC, 3001, Australia
| | - Mani Shrestha
- Bio-inspired Digital Sensing (BIDS) Lab, School of Media and Communication, RMIT University, Melbourne, VIC, 3001, Australia
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18
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Ishii HS, Kubota MX, Tsujimoto SG, Kudo G. Association between community assemblage of flower colours and pollinator fauna: a comparison between Japanese and New Zealand alpine plant communities. ANNALS OF BOTANY 2019; 123:533-541. [PMID: 30380008 PMCID: PMC6377100 DOI: 10.1093/aob/mcy188] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 10/09/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND AND AIMS Flower colour plays a major role in the attraction and decision-making of pollinators. Different functional groups of pollinators tend to prefer different flower colours, and therefor may lead to different flower colour compositions among different communities depending on the visual system of the dominant pollinators. However, few studies have investigated the linkage between pollinator fauna and flower colour composition in natural communities, a theme we explored in the present study. METHODS Flower spectral reflectance of 106 Japanese and 96 New Zealand alpine plants in the wavelength range 300-700 nm were measured. The composition of pollinator fauna in the communities and the types of pollinators for each plant species were also investigated. KEY RESULTS Based on bee and fly colour vision models, as well as a principal components analysis, considering phylogenetic non-independence between plant species, flower colours appeared to vary according to pollinator type rather than geographical region. Consequently, flower colour composition differed between the regions, reflecting the bee/fly mixed pollinator fauna of Japan and the fly-dominant pollinator fauna of New Zealand. According to the bee colour vision model, the majority of the colours of hymenopteran-pollinated flowers appeared to be discriminated by bees. In contrast, many of the colours of dipteran-pollinated flowers would not be discriminated by bees and flies. CONCLUSION The results suggest that the differences in flower colour composition between Japanese and New Zealand alpine communities are due to differences in the pollinator fauna in these communities rather than differences in abiotic factors between the geographical regions and the phylogenetic origin of the communities.
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Affiliation(s)
- Hiroshi S Ishii
- Graduate School of Science and Engineering, University of Toyama, Toyama, Japan
| | - Masahiro X Kubota
- Graduate School of Science and Engineering, University of Toyama, Toyama, Japan
| | - Shohei G Tsujimoto
- Graduate School of Science and Engineering, University of Toyama, Toyama, Japan
- Faculty of Science, Toho University, Funabashi, Japan
| | - Gaku Kudo
- Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan
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19
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Kemp JE, Bergh NG, Soares M, Ellis AG. Dominant pollinators drive non-random community assembly and shared flower colour patterns in daisy communities. ANNALS OF BOTANY 2019; 123:277-288. [PMID: 29992277 PMCID: PMC6344215 DOI: 10.1093/aob/mcy126] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 06/13/2018] [Indexed: 05/20/2023]
Abstract
Background and Aims As most plants rely on pollination for persistence in communities, pollination interactions should be important determinants of plant community assembly. Here, trait and phylogenetic null modelling approaches were combined with pollinator interaction networks to elucidate the processes structuring flower colour assembly patterns in Asteraceae communities in Namaqualand, South Africa. Methods Plant species were assigned to flower colour pattern categories (CPCs) that incorporate the complexity of the bulls-eye colour pattern, using pollinator vision models. Null models were used to assess whether daisy communities exhibit clustering (driven by filtering, facilitation or convergence) or overdispersion (driven by competitive exclusion or character displacement) of CPCs. Next, flower visitor networks were constructed for communities with non-random CPC assembly to confirm the functional role of pollinators in determining floral trait assembly. Key Results Plant species are unevenly distributed across CPCs, the majority of which are not phylogenetically conserved, suggesting that certain CPCs have a selective advantage. Clustering of CPCs in communities is more frequent than overdispersion, and this does not reflect non-random phylogenetic assembly. In most communities at least one CPC is overrepresented relative to null assemblages. Interaction networks show that each community has a single dominant pollinator that strongly interacts with the overrepresented CPC, suggesting a role for pollinator preferences in driving clustered assembly of CPCs within daisy communities. Conclusion This novel approach, which demonstrates non-random assembly of complex flower colour patterns and corroborates their functional association with particular pollinators, provides strong evidence that pollinators influence plant community assembly. Results suggest that in some community contexts the benefits of pollinator sharing outweigh the costs of heterospecific pollen transfer, generating clustered assembly. They also challenge the perception of generalized pollination in daisies, suggesting instead that complex daisy colour patterns represent a pollination syndrome trait linked to specific fly pollinators.
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Affiliation(s)
- Jurene E Kemp
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Nicola G Bergh
- The Compton Herbarium, Kirstenbosch Research Centre, South African National Biodiversity Institute, Newlands, Cape Town, South Africa
- The Bolus Herbarium, Department of Biological Sciences, H.W. Pearson Building, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Muri Soares
- The Bolus Herbarium, Department of Biological Sciences, H.W. Pearson Building, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Allan G Ellis
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
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20
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An L, Neimann A, Eberling E, Algora H, Brings S, Lunau K. The yellow specialist: dronefly Eristalis tenax prefers different yellow colours for landing and proboscis extension. ACTA ACUST UNITED AC 2018; 221:jeb.184788. [PMID: 30190319 DOI: 10.1242/jeb.184788] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 09/03/2018] [Indexed: 01/27/2023]
Abstract
Droneflies, imagoes of the hoverfly Eristalis tenax, are known to possess a preference for yellow flowers, i.e. they prefer to visit yellow flowers and prefer to extend the proboscis to yellow colours. In this study we disentangle these colour preferences by investigating the landing reaction and proboscis reflex with particular reference to intensity, spectral purity and dominant wavelength of colour stimuli and their UV reflection properties. In multiple-choice tests, naïve and non-trained flies prefer to land on yellow colours independent of their UV reflection characteristics, but also accept blue, white and pink colours if they absorb UV and are of sufficient brightness. Flies trained to land on colours other than yellow still prefer yellow colours to some extent. Moreover, the flies prefer bright over dark yellow colours even if trained to dark yellow ones. The flies refuse to land on dark colours of all hues. Naïve flies exhibit the proboscis reflex only to pure yellow pollen. These experiments show for the first time that landing in droneflies is triggered by a yellow colour independent of its UV reflection properties, but proboscis extension is triggered by yellow colours strongly absorbing blue and UV. The ability to discriminate colours is better than predicted by the categorical colour vision model. The colour preferences in E. tenax represent a fine-tuned ability to visit yellow flowers displaying a UV bull's-eye pattern.
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Affiliation(s)
- Lina An
- College of Plant Protection, Entomology Department, Hebei Agricultural University, 071000 Baoding, China.,Institute of Sensory Ecology, Biology Department, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany
| | - Alexander Neimann
- Institute of Sensory Ecology, Biology Department, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany
| | - Eugen Eberling
- Institute of Sensory Ecology, Biology Department, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany
| | - Hanna Algora
- Institute of Sensory Ecology, Biology Department, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany
| | - Sebastian Brings
- Institute of Sensory Ecology, Biology Department, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany
| | - Klaus Lunau
- Institute of Sensory Ecology, Biology Department, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany
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Abstract
Declines in wild and managed bee species richness and abundances have been observed throughout Europe and North America in recent decades. These declines have led to questions regarding pollination of wild and cultivated plants. In response to these concerns, efforts towards the conservation of pollinators have been initiated. Part of this conservation effort should be to provide the basic nutritional needs for bees. Nutrition plays one of the most important roles in bee growth, development, and reproduction. There is a large body of information regarding honey bee nutrition, whereas we lack nutritional information on native wild bees. Our knowledge of bumble bee nutritional needs has increased since the introduction of commercial rearing and sale of certain bumble bee species; however, there is still a lack of basic nutritional guidelines such as minimum dietary needs of proteins, amino acids, lipids, and sterols. The large difference in physiology and life history between honey bees and North American wild bees suggests that their nutritional requirements could be quite different.
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22
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Garcia JE, Shrestha M, Dyer AG. Flower signal variability overwhelms receptor-noise and requires plastic color learning in bees. Behav Ecol 2018. [DOI: 10.1093/beheco/ary127] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Jair E Garcia
- Bio-Inspired Digital Sensing (BIDS) Lab, School of Media and Communication, RMIT University, Melbourne, Victoria, Australia
| | - Mani Shrestha
- Bio-Inspired Digital Sensing (BIDS) Lab, School of Media and Communication, RMIT University, Melbourne, Victoria, Australia
- APIS Lab, Faculty of Information Technology, Monash University, Clayton, Victoria, Australia
| | - Adrian G Dyer
- Bio-Inspired Digital Sensing (BIDS) Lab, School of Media and Communication, RMIT University, Melbourne, Victoria, Australia
- Department of Physiology, Monash University, Clayton, Victoria 3168, Australia
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Kikuchi DW, Dornhaus A. How cognitive biases select for imperfect mimicry: a study of asymmetry in learning with bumblebees. Anim Behav 2018; 144:125-134. [PMID: 31439964 DOI: 10.1016/j.anbehav.2018.08.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Imperfect mimicry presents a paradox of incomplete adaptation - intuitively, closer resemblance should improve performance. Receiver psychology can often explain why mimetic signals do not always evolve to match those of their models. Here, we explored the influence of a pervasive and powerful cognitive bias where associative learning depends upon an asymmetric interaction between the cue (stimulus) and consequence (reinforcer), such as in rats, which will associate light and tone with shock, and taste with nausea, but not the converse. Can such biases alter selection for mimicry? We designed an artificial mimicry system where bees foraged on artificial flowers, so that colours could be switched between rewarding or aversive. We found that when the colour blue was paired with a sucrose reward, other cues were ignored, but not when blue was paired with aversive compounds. We also tested the hypothesis that costs of errors affect how receivers sample imperfect mimics. However, costs of errors did not affect bee visits to imperfect mimics in our study. We propose a novel hypothesis for imperfect mimicry, in which the pairing between specific cues and reinforcers allows an imperfect mimic to resemble multiple models simultaneously. Generally, our results emphasize the importance of receiver psychology for the evolution of signal complexity and specificity.
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Affiliation(s)
- David W Kikuchi
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, U.S.A
| | - Anna Dornhaus
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, U.S.A
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24
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Photobiology: How flowers get the blues to lure bees. Nature 2017; 550:467-468. [PMID: 29045387 DOI: 10.1038/nature24155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Meiners JM, Griswold TL, Harris DJ, Ernest SKM. Bees without Flowers: Before Peak Bloom, Diverse Native Bees Find Insect-Produced Honeydew Sugars. Am Nat 2017; 190:281-291. [PMID: 28731796 DOI: 10.1086/692437] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Bee foragers respond to complex visual, olfactory, and extrasensory cues to optimize searches for floral rewards. Their abilities to detect and distinguish floral colors, shapes, volatiles, and ultraviolet signals and even gauge nectar availability from changes in floral humidity or electric fields are well studied. Bee foraging behaviors in the absence of floral cues, however, are rarely considered. We observed 42 species of wild bees visiting inconspicuous, nonflowering shrubs during early spring in a protected Mediterranean habitat. We determined experimentally that these bees were accessing sugary honeydew secretions from scale insects without the aid of standard cues. While honeydew use is known among some social Hymenoptera, its use across a diverse community of solitary bees is a novel observation. The widespread ability of native bees to locate and use unadvertised, nonfloral sugars suggests unappreciated sensory mechanisms and/or the existence of an interspecific foraging network among solitary bees that may influence how native bees cope with scarcity of floral resources and increasing environmental change.
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