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Watanabe Y, Sakai S. Simulation analyses of the evolution of intra-inflorescence flowering patterns assuming selection on anthesis interval among individual flowers. J Theor Biol 2024; 594:111930. [PMID: 39181390 DOI: 10.1016/j.jtbi.2024.111930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 07/22/2024] [Accepted: 08/21/2024] [Indexed: 08/27/2024]
Abstract
What conditions select flowering patterns within inflorescences, or variation in the anthesis interval within inflorescences among plants? Under what conditions are gradual blooming and simultaneous blooming, both traits related to floral display size, advantageous? We constructed a simulation model in which the opening times and longevities of individual flowers within inflorescences, the sizes of attractive structures of individual flowers, and the numbers of ovules and pollen grains produced by individual flowers evolve. Individual plants in the population compete for pollinators, and plants are selected by pollinators according to their floral display sizes and amounts of resources allocated to attractive structures. We found that, if the proportion of pollen on a pollinator deposited on a stigma was low, gradual blooming did not evolve even if inbreeding depression was greater than 0.5. This is because the amount of outcross-pollen on pollinators decreased at a low rate during flower visits within a single inflorescence, and the selfing rate was suppressed to a low level even if the floral display size was large. On the other hand, if the proportion of pollen deposition was high, gradual blooming evolved even if inbreeding depression was smaller than 0.5. This may be because gradual blooming can enhance pollen delivery to other plants by reducing the loss of self-pollen by geitonogamy. On the other hand, allocation ratios among floral organs (female and male organs and attractive structures) were independent of the degree of simultaneous and gradual blooming within inflorescences. We concluded that the evolution of gradual blooming is more strongly affected by the proportion of pollen on a pollinator deposited on a stigma than by inbreeding depression.
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Affiliation(s)
- Yu Watanabe
- Department of Ecology and Evolutionary Biology, Graduate School of Life Sciences, Tohoku University, Sendai 980-8578, Japan
| | - Satoki Sakai
- Department of Ecology and Evolutionary Biology, Graduate School of Life Sciences, Tohoku University, Sendai 980-8578, Japan.
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2
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Mitchell RJ, Starvaggi D, Fitzgerald V, Karron JD. The timing of visits by large and small bees differentially affects pollination success in Mimulus ringens. AMERICAN JOURNAL OF BOTANY 2024; 111:e16375. [PMID: 39004802 DOI: 10.1002/ajb2.16375] [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: 11/13/2023] [Revised: 05/09/2024] [Accepted: 05/09/2024] [Indexed: 07/16/2024]
Abstract
PREMISE Cross-fertilization in most flowering plants is facilitated by mobile animals that transport pollen while foraging for floral rewards. The contributions of different visitors can vary widely, depending on the amount of pollen transferred during a single visit and on the frequency and timing of the visits of each pollinator taxon. METHODS We used three approaches to measure the pollination value of bees that visit Mimulus ringens: pollinator interviews, field population observations, and caging studies. RESULTS The single-visit effectiveness of small bees (primarily Halictidae) was only half that of larger bees (primarily Bombus) for pollen delivery and removal. In five field populations, we found substantial temporal and spatial variation in visitation and pollination. In most sites big bees were active before 08:00 hours, and by 10:00-11:00 hours, stigmas were usually fully pollinated and closed, and little pollen remained in anthers. Small bees seldom visited before 10:00 hours. Excluding big bees from plants confirmed that pollination is reduced and delayed in this ecological context. CONCLUSIONS Big bees are the primary pollinators of M. ringens, accounting for at least 75% of seed production. Not only are they more effective per visit, in most situations they also visit before small bees become active. Although small bees are not usually important pollinators of M. ringens, they have the potential to partially replace them as a "fail-safe" pollinator in contexts where big bees are not abundant. In a world where pollinator abundance is declining, such backup pollinators may be important for maintaining plant reproduction.
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Affiliation(s)
| | | | | | - Jeffrey D Karron
- Department of Biological Sciences, University of Wisconsin, Milwaukee, 53211, WI, USA
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3
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de Manincor N, Fisogni A, Rafferty NE. Warming of experimental plant-pollinator communities advances phenologies, alters traits, reduces interactions and depresses reproduction. Ecol Lett 2023; 26:323-334. [PMID: 36592334 PMCID: PMC10107705 DOI: 10.1111/ele.14158] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 12/01/2022] [Accepted: 12/07/2022] [Indexed: 01/03/2023]
Abstract
Climate change may disrupt plant-pollinator mutualisms by generating phenological asynchronies and by altering traits that shape interaction costs and benefits. Our knowledge is limited to studies that manipulate only one partner or focus on either phenological or trait-based mismatches. We assembled communities of three annual plants and a solitary bee prior to flowering and emergence to test how springtime warming affects phenologies, traits, interactions and reproductive output. Warming advanced community-level flowering onset, peak and end but did not alter bee emergence. Warmed plant communities produced fewer and smaller flowers with less, more-concentrated nectar, reducing attractiveness, and warmed bees were more generalized in their foraging, reducing their effectiveness. Plant-bee interactions were less frequent, shorter and peaked earlier under warming. As a result, warmed plants produced fewer, lighter seeds, indicating pollinator-mediated fitness costs. Climate change will perturb plant-pollinator mutualisms, causing wide-ranging effects on partner species and diminishing the ecosystem service they provide.
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Affiliation(s)
- Natasha de Manincor
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, California, USA
| | - Alessandro Fisogni
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, California, USA
| | - Nicole E Rafferty
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, California, USA
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4
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McCombs AL, Debinski D, Reinhardt K, Germino MJ, Caragea P. Warming temperatures affect meadow‐wide nectar resources, with implications for plant–pollinator communities. Ecosphere 2022. [DOI: 10.1002/ecs2.4162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Audrey L. McCombs
- Department of Statistics, Ecology and Evolutionary Biology Program Iowa State University Ames Iowa USA
| | - Diane Debinski
- Department of Ecology Montana State University Bozeman Montana USA
| | - Keith Reinhardt
- Department of Biological Sciences Idaho State University Pocatello Idaho USA
| | - Matthew J. Germino
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center Boise Idaho USA
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5
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McPeek MA, McPeek SJ, Bronstein JL. Nectar dynamics and the coexistence of two plants that share a pollinator. OIKOS 2022. [DOI: 10.1111/oik.08869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mark A. McPeek
- Dept of Biological Sciences, Dartmouth College Hanover NH USA
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6
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Moquet L, Jacquemart A, Dufay M, De Cauwer I. Effects of sexual dimorphism on pollinator behaviour in a dioecious species. OIKOS 2021. [DOI: 10.1111/oik.08662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Laura Moquet
- Univ. Lille, CNRS, UMR 8198 – Evo‐Eco‐Paleo Lille France
- UMR PVBMT, CIRAD Saint Pierre La Réunion France
| | - Anne‐Laure Jacquemart
- Genetics, Reproduction and Populations Research Group, Earth and Life Inst., Univ. Catholique de Louvain Louvain‐la‐Neuve Belgium
| | - Mathilde Dufay
- Univ. Lille, CNRS, UMR 8198 – Evo‐Eco‐Paleo Lille France
- CEFE, Univ. Montpellier, CNRS, EPHE, IRD Montpellier France
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7
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Kuppler J, Kotowska MM. A meta-analysis of responses in floral traits and flower-visitor interactions to water deficit. GLOBAL CHANGE BIOLOGY 2021; 27:3095-3108. [PMID: 33774883 DOI: 10.1111/gcb.15621] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Accepted: 03/10/2021] [Indexed: 06/12/2023]
Abstract
Alterations in water availability and drought events as predicted by climate change scenarios will increasingly impact natural communities with effects already emerging at present. Water deficit leads to increasing physiological stress in plants, likely affecting floral development and causing changes in floral morphology, nectar and pollen production or scent. Understanding how these floral traits are altered by water deficit is necessary to predict changes in plant-pollinator interactions and how communities are impacted in the future. Here we employ a meta-analysis approach to synthesize the current evidence of experimental water deficit on floral traits and plant-pollinator interactions. Furthermore, we explore experimental factors potentially increasing heterogeneity between studies and provide ideas how to enhance comparability between studies. In the end, we highlight future directions and knowledge gaps for floral traits and plant-pollinator interactions under water deficit. Our analysis showed consistent decreases in floral size, number of flowers and nectar volume to reduced water availability. Other floral traits such as the start of flowering or herkogamy showed no consistent pattern. This indicates that effects of reduced water availability differ between specific traits that are potentially involved in different functions such as pollinator attraction or efficiency. We found no general decreasing visitation rates with water deficit for flower-visitor interactions. Furthermore, the comparison of available studies suggests that increased reporting of plant stress severity and including more hydraulic and physiological measurements will improve the comparability across experiments and aid a more mechanistic understanding of plant-pollinator interactions under altered environmental conditions. Overall, our results show that water deficit has the potential to strongly affect plant-pollinator interactions via changes in specific floral traits. Linking these changes to pollination services and pollinator performance is one crucial step for understanding how changing water availability and drought events under climate change will alter plant and pollinator communities.
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Affiliation(s)
- Jonas Kuppler
- Institute of Evolutionary Ecology and Conservation Genomics, Ulm University, Ulm, Germany
| | - Martyna M Kotowska
- Plant Ecology and Ecosystems Research, University of Göttingen, Göttingen, Germany
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8
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From the ground up: Building predictions for how climate change will affect belowground mutualisms, floral traits, and bee behavior. CLIMATE CHANGE ECOLOGY 2021. [DOI: 10.1016/j.ecochg.2021.100013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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9
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Cervantes-Loreto A, Ayers CA, Dobbs EK, Brosi BJ, Stouffer DB. The context dependency of pollinator interference: How environmental conditions and co-foraging species impact floral visitation. Ecol Lett 2021; 24:1443-1454. [PMID: 33942455 DOI: 10.1111/ele.13765] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/24/2021] [Accepted: 04/03/2021] [Indexed: 11/29/2022]
Abstract
Animals often change their behaviour in the presence of other species and the environmental context they experience, and these changes can substantially modify the course their populations follow. In the case of animals involved in mutualistic interactions, it is still unclear how to incorporate the effects of these behavioural changes into population dynamics. We propose a framework for using pollinator functional responses to examine the roles of pollinator-pollinator interactions and abiotic conditions in altering the times between floral visits of a focal pollinator. We then apply this framework to a unique foraging experiment with different models that allow resource availability and sublethal exposure to a neonicotinoid pesticide to modify how pollinators forage alone and with co-foragers. We found that all co-foragers interfere with the focal pollinator under at least one set of abiotic conditions; for most species, interference was strongest at higher levels of resource availability and with pesticide exposure. Overall our results highlight that density-dependent responses are often context-dependent themselves.
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Affiliation(s)
- Alba Cervantes-Loreto
- Centre for Integrative Ecology, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Carolyn A Ayers
- Department of Environmental Sciences, Emory University, Atlanta, GA, USA
| | - Emily K Dobbs
- Department of Environmental Sciences, Emory University, Atlanta, GA, USA
| | - Berry J Brosi
- Department of Biology, University of Washington, Seattle, WA, USA
| | - Daniel B Stouffer
- Centre for Integrative Ecology, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
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10
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Unexpectedly low paternal diversity is associated with infrequent pollinator visitation for a bird-pollinated plant. Oecologia 2021; 196:937-950. [PMID: 33870456 DOI: 10.1007/s00442-021-04906-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 03/23/2021] [Indexed: 10/21/2022]
Abstract
The behaviour of pollinators has important consequences for plant mating. Nectar-feeding birds often display behaviour that results in more pollen carryover than insect pollinators, which is predicted to result in frequent outcrossing and high paternal diversity for bird-pollinated plants. We tested this prediction by quantifying mating system parameters and bird visitation in three populations of an understory bird-pollinated herb, Anigozanthos humilis (Haemodoraceae). Microsatellite markers were used to genotype 131 adult plants, and 211 seeds from 23 maternal plants, from three populations. While outcrossing rates were high, estimates of paternal diversity were surprisingly low compared with other bird-pollinated plants. Despite nectar-feeding birds being common at the study sites, visits to A. humilis flowers were infrequent (62 visits over 21,552 recording hours from motion-triggered cameras, or equivalent to one visit per flower every 10 days), and the majority (76%) were by a single species, the western spinebill Acanthorhynchus superciliosus (Meliphagidae). Pollen counts from 30 captured honeyeaters revealed that A. humilis comprised just 0.3% of the total pollen load. For 10 western spinebills, A. humilis pollen comprised only 4.1% of the pollen load, which equated to an average of 3.9 A. humilis pollen grains per bird. Taken together, our findings suggest that low visitation rates and low pollen loads of floral visitors have led to the low paternal diversity observed in this understory bird-pollinated herb. As such, we shed new light on the conditions that can lead to departures from high paternal diversity for plants competing for the pollination services of generalist nectar-feeding birds.
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11
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Torices R, DeSoto L, Narbona E, Gómez JM, Pannell JR. Effects of the Relatedness of Neighbours on Floral Colour. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.589781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The reproductive success of plants depends both on their phenotype and the local neighbourhood in which they grow. Animal-pollinated plants may benefit from increased visitation when surrounded by attractive conspecific individuals, via a “magnet effect.” Group attractiveness is thus potentially a public good that can be exploited by individuals, with selfish exploitation predicted to depend on genetic relatedness within the group. Petal colour is a potentially costly trait involved in floral signalling and advertising to pollinators. Here, we assessed whether petal colour was plastically sensitive to the relatedness of neighbours in the annual herb Moricandia moricandioides, which produces purple petals through anthocyanin pigment accumulation. We also tested whether petal colour intensity was related to nectar volume and sugar content in a context-dependent manner. Although both petal colour and petal anthocyanin concentration did not significantly vary with the neighbourhood configuration, plants growing with kin made a significantly higher investment in petal anthocyanin pigments as a result of the greater number and larger size of their flowers. Moreover the genetic relatedness of neighbours significantly modified the relationship between floral signalling and reward quantity: while focal plants growing with non-kin showed a positive relationship between petal colour and nectar production, plants growing with kin showed a positive relationship between number of flowers and nectar volume, and sugar content. The observed plastic response to group relatedness might have important effects on pollinator behaviour and visitation, with direct and indirect effects on plant reproductive success and mating patterns, at least in those plant species with patchy and genetically structured populations.
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12
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Ortiz PL, Fernández‐Díaz P, Pareja D, Escudero M, Arista M. Do visual traits honestly signal floral rewards at community level? Funct Ecol 2020. [DOI: 10.1111/1365-2435.13709] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Pedro L. Ortiz
- Departamento de Biología Vegetal y Ecología Universidad de Sevilla Sevilla Spain
| | - Pilar Fernández‐Díaz
- Departamento de Biología Vegetal y Ecología Universidad de Sevilla Sevilla Spain
| | - Daniel Pareja
- Departamento de Biología Vegetal y Ecología Universidad de Sevilla Sevilla Spain
| | - Marcial Escudero
- Departamento de Biología Vegetal y Ecología Universidad de Sevilla Sevilla Spain
| | - Montserrat Arista
- Departamento de Biología Vegetal y Ecología Universidad de Sevilla Sevilla Spain
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13
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Moquet L, Lateur L, Jacquemart AL, De Cauwer I, Dufay M. Temporal dynamics of sexual dimorphism in a dioecious species. ANNALS OF BOTANY 2020; 126:471-480. [PMID: 32386315 PMCID: PMC7424764 DOI: 10.1093/aob/mcaa088] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 05/04/2020] [Indexed: 06/01/2023]
Abstract
BACKGROUND AND AIMS Sexual dimorphism for floral traits is common in dioecious plant species. Beyond its significance for understanding how selection acts on plant traits through male vs. female reproductive function, sexual dimorphism has also been proposed as a possible risky characteristic for insect-pollinated plants, as it could drive pollinators to forage mostly on male plants. However, even though most flowering plant species spread their flowering across several weeks or months, the temporal variation of floral phenotypes and sexual dimorphism have rarely been investigated. METHODS We performed a survey of male and female plants from the dioecious generalist-pollinated Silene dioica (Caryophyllaceae) in a common garden experiment, over two consecutive flowering seasons. Flower number and floral size were measured each week, as well as pollen quantity and viability in male plants. KEY RESULTS Sexual dimorphism was found for all investigated floral traits, with males showing an overall higher investment in flower production and flower size. Males and females showed a similar temporal decline in flower size. The temporal dynamics of daily flower number differed between sexes, with males showing a peak in the middle of their flowering season, whereas flower production by females was quite stable over time. At the scale of the experimental population, both individual and floral sex ratios appeared to vary across the flowering season. Moreover, because the onset of flowering varied among plants, the magnitude of sexual dimorphism in floral size also fluctuated strongly through time. CONCLUSIONS Capturing male/female differences with only one temporal measurement per population may not be informative. This opens stimulating questions about how pollinator behaviour and resulting pollination efficiency may vary across the flowering season.
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Affiliation(s)
- L Moquet
- Univ. Lille, CNRS, Lille, France
- UMR PVBMT, Saint Pierre, La Réunion, France
- UCLouvain, Earth and Life Institute, Louvain-la-Neuve, Belgium
| | - L Lateur
- Univ. Lille, CNRS, Lille, France
| | - A-L Jacquemart
- UCLouvain, Earth and Life Institute, Louvain-la-Neuve, Belgium
| | | | - M Dufay
- Univ. Lille, CNRS, Lille, France
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valery Montpellier, Montpellier, France
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14
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Dibble AC, Drummond FA, Stack LB. Bee Visitation on Flowers in Maine, United States, Reveals the Relative Attractiveness of Plants Through Space and Time: Part I. ENVIRONMENTAL ENTOMOLOGY 2020; 49:726-737. [PMID: 32270187 DOI: 10.1093/ee/nvaa028] [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: 09/16/2019] [Indexed: 06/11/2023]
Abstract
Bee reservoirs can be effective in agricultural and habitat restoration projects, but the relative attractiveness of plants is not fully understood. To improve plant selection with better knowledge of spatial, temporal, and competition aspects, we tested up to 90 plant subjects from 2012 to 2015 at four sites in Maine. We recognized Apis mellifera L., Bombus ternarius Say, 1837, 'Most Bombus' (except B. ternarius), 'Halictidae' and 'Other Bees' (collectively the so-called 'bee groups') on open flowers in three 1-min periods per site and day, with numerous repeated observations per plant taxon. In 14,311 observations, we recorded 17,792 bees in 61 species. Most-visited plants included Asclepias tuberosa, Borago officinalis, Clethra alnifolia cv. Hummingbird (especially by A. mellifera), Melilotus officinalis, Origanum vulgare, Rosa palustris (especially before 1400 hours), Spiraea alba var. latifolia, and taxa in the family Asteraceae. Early-flowering shrubs were visited, especially by 'Other Bees'. Bee groups each ranked plants uniquely, with some overlap, and differed in most-visited of six plant taxa that we had included in all 4 yr and sites. For 'All Bees' among 84 plant taxa, the most-visited plants were M. officinalis (June), A. tuberosa (July), and C. alnifolia (August). Indicator Species Analysis revealed low bee fidelity to host plants for all but a few plant taxa. Apis mellifera differed from native bees in plants it visited intensively, with some overlap (e.g., A. tuberosa), and was associated with increased visitation on seven plant taxa by 'Most Bombus' and B. ternarius.
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Affiliation(s)
- Alison C Dibble
- School of Biology and Ecology, University of Maine, Orono, ME
| | - Francis A Drummond
- School of Biology and Ecology, and Cooperative Extension, University of Maine, Orono, ME
| | - Lois Berg Stack
- School of Food and Agriculture, and Cooperative Extension University of Maine, Orono, ME
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15
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Pyke GH, Kalman JRM, Bordin DM, Blanes L, Doble PA. Patterns of floral nectar standing crops allow plants to manipulate their pollinators. Sci Rep 2020; 10:1660. [PMID: 32015366 PMCID: PMC6997191 DOI: 10.1038/s41598-020-58102-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 01/03/2020] [Indexed: 12/02/2022] Open
Abstract
‘Pollination syndromes’ involving floral nectar have eluded satisfactory evolutionary explanation. For example, floral nectars for vertebrate-pollinated plants average low sugar concentrations, while such animals prefer high concentrations, perplexing pollination biologists and arousing recent controversy. Such relationships should result from evolutionary games, with plants and pollinators adopting Evolutionarily Stable Strategies, and nectar manipulating rather than attracting pollinators. Plant potential to manipulate pollinators depends on relationships between neighbouring flowers within plants, for all nectar attributes, but this has not been investigated. We measured nectar volume, concentration and sugar composition for open flowers on naturally-growing Blandfordia grandiflora plants, presenting classic bird-pollinated plant syndrome. To evaluate potential pollinator manipulation through nectar, we analysed relationships between neighbouring flowers for nectar volume, concentration, proportion sucrose, log(fructose/glucose), and sugar weight. To evaluate potential attraction of repeat-visits to flowers or plants through nectar, we compared attributes between successive days. Nearby flowers were positively correlated for all attributes, except log(fructose/glucose) as fructose≈glucose. Most relationships between nectar attributes for flowers and plants on successive days were non-significant. Nectar-feeding pollinators should therefore decide whether to visit another flower on a plant, based on all attributes of nectar just-obtained, enabling plants to manipulate pollinators through adjusting nectar. Plants are unlikely to attract repeat pollinator-visits through nectar production. Floral nectar evolution is conceptually straightforward but empirically challenging. A mutant plant deviating from the population in attributes of nectar-production per flower would manipulate, rather than attract, nectar-feeding pollinators, altering pollen transfer, hence reproduction. However, links between floral nectar and plant fitness present empirical difficulties.
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Affiliation(s)
- Graham H Pyke
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, CN, 650201, Kunming, PR China. .,Department of Biological Sciences, Macquarie University, Ryde, NSW, 2109, Australia.
| | - John R M Kalman
- School of Mathematical & Physical Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Dayanne M Bordin
- School of Mathematical & Physical Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Lucas Blanes
- School of Mathematical & Physical Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia.,Laboratory for Applied Science and Technology in Health, Carlos Chagas Institute, Oswaldo Cruz Foundation (Fiocruz), Curitiba, Brazil
| | - Philip A Doble
- School of Mathematical & Physical Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia
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16
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Wang XY, Tang J, Wu T, Wu D, Huang SQ. Bumblebee Rejection of Toxic Pollen Facilitates Pollen Transfer. Curr Biol 2019; 29:1401-1406.e4. [DOI: 10.1016/j.cub.2019.03.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 01/02/2019] [Accepted: 03/13/2019] [Indexed: 11/26/2022]
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17
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Pasquaretta C, Jeanson R, Pansanel J, Raine NE, Chittka L, Lihoreau M. A spatial network analysis of resource partitioning between bumblebees foraging on artificial flowers in a flight cage. MOVEMENT ECOLOGY 2019; 7:4. [PMID: 30828455 PMCID: PMC6383269 DOI: 10.1186/s40462-019-0150-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 02/01/2019] [Indexed: 05/21/2023]
Abstract
BACKGROUND Individual bees exhibit complex movement patterns to efficiently exploit small areas within larger plant populations. How such individual spatial behaviours scale up to the collective level, when several foragers visit a common area, has remained challenging to investigate, both because of the low resolution of field movement data and the limited power of the statistical descriptors to analyse them. To tackle these issues we video recorded all flower visits (N = 6205), and every interaction on flowers (N = 628), involving foragers from a bumblebee (Bombus terrestris) colony in a large outdoor flight cage (880 m2), containing ten artificial flowers, collected on five consecutive days, and analysed bee movements using networks statistics. RESULTS Bee-flower visitation networks were significantly more modular than expected by chance, indicating that foragers minimized overlaps in their patterns of flower visits. Resource partitioning emerged from differences in foraging experience among bees, and from outcomes of their interactions on flowers. Less experienced foragers showed lower activity and were more faithful to some flowers, whereas more experienced foragers explored the flower array more extensively. Furthermore, bees avoided returning to flowers from which they had recently been displaced by a nestmate, suggesting that bees integrate memories of past interactions into their foraging decisions. CONCLUSION Our observations, under high levels of competition in a flight cage, suggest that the continuous turnover of foragers observed in colonies can led to efficient resource partitioning among bees in natural conditions.
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Affiliation(s)
- Cristian Pasquaretta
- Research Center on Animal Cognition (CRCA), Center for Integrative Biology (CBI); CNRS, University Paul Sabatier, Toulouse, France
| | - Raphael Jeanson
- Research Center on Animal Cognition (CRCA), Center for Integrative Biology (CBI); CNRS, University Paul Sabatier, Toulouse, France
| | - Jerome Pansanel
- Institut Pluridisciplinaire Hubert Curien, CNRS, Strasbourg, France
| | - Nigel E. Raine
- School of Biological Sciences, Royal Holloway University of London, Egham, TW20 0EX UK
- School of Environmental Sciences, University of Guelph, Guelph, Ontario N1G 2W1 Canada
| | - Lars Chittka
- Department of Biological and Experimental Psychology, School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS UK
- Wissenschaftskolleg, Institute for Advanced Study, Wallotstrasse 19, 14193 Berlin, Germany
| | - Mathieu Lihoreau
- Research Center on Animal Cognition (CRCA), Center for Integrative Biology (CBI); CNRS, University Paul Sabatier, Toulouse, France
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18
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Parachnowitsch AL, Manson JS, Sletvold N. Evolutionary ecology of nectar. ANNALS OF BOTANY 2019; 123:247-261. [PMID: 30032269 PMCID: PMC6344224 DOI: 10.1093/aob/mcy132] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Accepted: 06/16/2018] [Indexed: 05/24/2023]
Abstract
Background Floral nectar is an important determinant of plant-pollinator interactions and an integral component of pollination syndromes, suggesting it is under pollinator-mediated selection. However, compared to floral display traits, we know little about the evolutionary ecology of nectar. Combining a literature review with a meta-analysis approach, we summarize the evidence for heritable variation in nectar traits and link this variation to pollinator response and plant fitness. We further review associations between nectar traits and floral signals and discuss them in the context of honest signalling and targets of selection. Scope Although nectar is strongly influenced by environmental factors, heritable variation in nectar production rate has been documented in several populations (mean h2 = 0.31). Almost nothing is known about heritability of other nectar traits, such as sugar and amino acid concentrations. Only a handful of studies have quantified selection on nectar traits, and few find statistically significant selection. Pollinator responses to nectar traits indicate they may drive selection, but studies tying pollinator preferences to plant fitness are lacking. So far, only one study conclusively identified pollinators as selective agents on a nectar trait, and the role of microbes, herbivores, nectar robbers and abiotic factors in nectar evolution is largely hypothetical. Finally, there is a trend for positive correlations among floral cues and nectar traits, indicating honest signalling of rewards. Conclusions Important progress can be made by studies that quantify current selection on nectar in natural populations, as well as experimental approaches that identify the target traits and selective agents involved. Signal-reward associations suggest that correlational selection may shape evolution of nectar traits, and studies exploring these more complex forms of natural selection are needed. Many questions about nectar evolution remain unanswered, making this a field ripe for future research.
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Affiliation(s)
- Amy L Parachnowitsch
- Plant Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
- Department of Biology, University of New Brunswick, Fredericton, New Brunswick, Canada
| | - Jessamyn S Manson
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Nina Sletvold
- Plant Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
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19
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Minnaar C, Anderson B, de Jager ML, Karron JD. Plant-pollinator interactions along the pathway to paternity. ANNALS OF BOTANY 2019; 123:225-245. [PMID: 30535041 PMCID: PMC6344347 DOI: 10.1093/aob/mcy167] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 11/23/2018] [Indexed: 05/09/2023]
Abstract
Background The male fitness pathway, from pollen production to ovule fertilization, is thought to strongly influence reproductive trait evolution in animal-pollinated plants. This pathway is characterized by multiple avenues of pollen loss which may lead to reductions in male fitness. However, empirical data on the mechanistic processes leading to pollen loss during transport are limited, and we therefore lack a comprehensive understanding of how male fitness is influenced by each step in the pollination process. Scope This review assesses the history of studying male function in plants and identifies critical gaps in our understanding of the ecology and evolution of pollen transport. We explore male reproductive function along the steps of the pathway to paternity and discuss evolutionary options to overcome barriers to siring success. In particular, we present a newly emerging idea that bodies of pollinators function as a dynamic arena facilitating intense male-male competition, where pollen of rival males is constantly covered or displaced by competitors. This perspective extends the pollen-competitive arena beyond the confines of the stigma and style, and highlights the opportunity for important new breakthroughs in the study of male reproductive strategies and floral evolution.
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Affiliation(s)
- Corneile Minnaar
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Bruce Anderson
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Marinus L de Jager
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Jeffrey D Karron
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
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20
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Mora-Carrera E, Castañeda-Zárate M, Fornoni J, Boege K, Domínguez CA. On the adaptive value of monomorphic versus dimorphic enantiostyly in Solanum rostratum. ANNALS OF BOTANY 2019; 123:205-212. [PMID: 30184097 PMCID: PMC6344091 DOI: 10.1093/aob/mcy162] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 08/09/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND AND AIMS Enantiostyly is a reproductive system with heteromorphic flowers characterized by asymmetrical deflection of the style, either to the left or to the right of the floral axis. There are two types of enantiostyly. In monomorphic enantiostyly, plants produce the two types of flowers in the same individual. Dimorphic enantiostyly is restricted to only seven species and their populations consist of individuals producing either the right or the left flower type. It is hypothesized that the dimorphic form is derived from monomorphic ancestors because it functions as an outcrossing mechanism. We tested this latter hypothesis and investigated if monomorphic enantiostyly is resistant to invasion by individuals with dimorphic enantiostyly, because it functions as a reproductive assurance mechanism. METHODS To determine the conditions favouring the invasion of dimorphic enantiostyly, measurements of reproductive success and outcrossing rates in 15 natural flowering patches of Solanum rostratum were made. To test if monomorphic enantiostyly provides a reproductive assurance mechanism, experimental plants with either manually created dimorphic or natural monomorphic reproductive systems were exposed to two different pollination scenarios (flower density treatments), and reproductive success and outcrossing rates were measured. KEY RESULTS Naturally flowering patches experienced severe pollination limitation, showed marked differences in reproductive success and had relatively high outcrossing rates. Plants in the experimental patches also showed pollination limitation and high outcrossing rates. Individuals with dimorphic enantiostyly expressed higher reproductive and outcrossing advantages under high-density conditions. These advantages disappeared in the low-density treatment, where the monomorphic form attained a higher reproductive success and no differences in outcrossing rates were detected. CONCLUSIONS Monomorphic enantiostyly should be resistant to invasion of the dimorphic form because the prevalent ecological conditions favour the maintenance of geitonogamous individuals that are able to take advantage of ecological heterogeneity and generalized pollination limitation.
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Affiliation(s)
- Emiliano Mora-Carrera
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Miguel Castañeda-Zárate
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Juan Fornoni
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Karina Boege
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - César A Domínguez
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, México
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21
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Akter A, Biella P, Klecka J. Effects of small-scale clustering of flowers on pollinator foraging behaviour and flower visitation rate. PLoS One 2017; 12:e0187976. [PMID: 29136042 PMCID: PMC5685580 DOI: 10.1371/journal.pone.0187976] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 10/30/2017] [Indexed: 12/02/2022] Open
Abstract
Plants often grow in clusters of various sizes and have a variable number of flowers per inflorescence. This small-scale spatial clustering affects insect foraging strategies and plant reproductive success. In our study, we aimed to determine how visitation rate and foraging behaviour of pollinators depend on the number of flowers per plant and on the size of clusters of multiple plants using Dracocephalum moldavica (Lamiaceae) as a target species. We measured flower visitation rate by observations of insects visiting single plants and clusters of plants with different numbers of flowers. Detailed data on foraging behaviour within clusters of different sizes were gathered for honeybees, Apis mellifera, the most abundant visitor of Dracocephalum in the experiments. We found that the total number of flower visitors increased with the increasing number of flowers on individual plants and in larger clusters, but less then proportionally. Although individual honeybees visited more flowers in larger clusters, they visited a smaller proportion of flowers, as has been previously observed. Consequently, visitation rate per flower and unit time peaked in clusters with an intermediate number of flowers. These patterns do not conform to expectations based on optimal foraging theory and the ideal free distribution model. We attribute this discrepancy to incomplete information about the distribution of resources. Detailed observations and video recordings of individual honeybees also showed that the number of flowers had no effect on handling time of flowers by honeybees. We evaluated the implications of these patterns for insect foraging biology and plant reproduction.
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Affiliation(s)
- Asma Akter
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, České Budějovice, Czech Republic
- Department of Zoology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Paolo Biella
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, České Budějovice, Czech Republic
- Department of Zoology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Jan Klecka
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, České Budějovice, Czech Republic
- * E-mail:
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22
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Broyles SB, Wyatt R. A REEXAMINATION OF THE POLLEN-DONATION HYPOTHESIS IN AN EXPERIMENTAL POPULATION OF ASCLEPIAS EXALTATA. Evolution 2017; 49:89-99. [DOI: 10.1111/j.1558-5646.1995.tb05961.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/1992] [Accepted: 01/20/1994] [Indexed: 11/29/2022]
Affiliation(s)
| | - Robert Wyatt
- Department of Botany; University of Georgia; Athens Georgia 30602
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23
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Sakai S. ALLOCATION TO ATTRACTIVE STRUCTURES IN ANIMAL-POLLINATED FLOWERS. Evolution 2017; 47:1711-1720. [DOI: 10.1111/j.1558-5646.1993.tb01263.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/1991] [Accepted: 02/05/1993] [Indexed: 11/30/2022]
Affiliation(s)
- Satoki Sakai
- Botanical Gardens; Faculty of Science, University of Tokyo; 3-7-1 Hakusan Bunkyo-ku Tokyo 112 Japan
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24
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Broyles SB, Wyatt R. PATERNITY ANALYSIS IN A NATURAL POPULATION OF ASCLEPIAS EXALTATA: MULTIPLE PATERNITY, FUNCTIONAL GENDER, AND THE "POLLEN-DONATION HYPOTHESIS". Evolution 2017; 44:1454-1468. [PMID: 28564301 DOI: 10.1111/j.1558-5646.1990.tb03838.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/1989] [Accepted: 12/22/1989] [Indexed: 11/30/2022]
Abstract
Recently, some evolutionary biologists have argued that selection on the male component of fitness shapes the evolution of reproductive characters in angiosperms. Floral features, such as inflorescence size, that lead to increased insect visitation without a concomitant increase in seed production are viewed as adaptations to enhance the probability of fathering seeds on other plants. In tests of this "pollen donation hypothesis," male reproductive success has usually been measured indirectly by flower production, pollinator visitation, or pollen removal. We tested the pollen donation hypothesis directly by quantifying the number of seeds sired by individual genotypes in a natural population of poke milkweed, Asclepias exaltata, in southwestern Virginia. Multiple paternity was low within fruits, a fact which allowed us to use genotypes of progeny arrays to identify a unique pollen parent for 85% of the fruits produced in the population. Seeds sired (male success) and seeds produced (female success) were significantly correlated with flower number per plant (for male success, r = 0.32, P > 0.05; for female success, r = 0.66, P > 0.001). While the number of pollinaria removed, the usual estimator of male success in milkweeds, was highly correlated with numbers of seeds sired (r = 0.47; P > 0.001), it was even more highly correlated with numbers of seeds produced (r = 0.71, P > 0.001). Analysis of functional gender indicated that plants with many flowers did not behave primarily as males. In fact, individuals with the highest total reproductive success contributed equally as males and females. Furthermore, estimates of gender based on numbers of flowers produced or pollinaria removed overestimated the number of functional males in the population. In pollen-limited species, such as many milkweeds, proportional increases in both male and female reproductive success indicate the potential for selection to shape the evolution of large floral displays through both male and female functions.
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Affiliation(s)
- Steven B Broyles
- Department of Botany, University of Georgia, Athens, GA, 30602, USA
| | - Robert Wyatt
- Department of Botany, University of Georgia, Athens, GA, 30602, USA
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25
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Stanton M, Young HJ, Ellstrand NC, Clegg JM. CONSEQUENCES OF FLORAL VARIATION FOR MALE AND FEMALE REPRODUCTION IN EXPERIMENTAL POPULATIONS OF WILD RADISH, RAPHANUS SATIVUS L. Evolution 2017; 45:268-280. [PMID: 28567875 DOI: 10.1111/j.1558-5646.1991.tb04402.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/1990] [Accepted: 10/18/1990] [Indexed: 11/30/2022]
Abstract
We documented effects of floral variation on seed paternity and maternal fecundity in a series of small experimental populations of wild radish, R. sativus. Each population was composed of two competing pollen donor groups with contrasting floral morphologies and several designated maternal plants. Progeny testing with electrophoretic markers allowed us to measure paternal success. Realized fecundity by each maternal plant and the fraction of those seeds attributable to each pollen donor group were used as outcome variables in path analysis to explore relationships between floral characters (petal size, pollen grain number per flower, and modal pollen grain size), pollinator visitation patterns, and reproductive success. A wide range of pollinator taxa visited the experimental populations, and patterns of discrimination appeared to vary among them. The impact of visitation on male and female reproduction also varied among taxa; visits of small native bees significantly increased paternal success, while those of honey bees reduced male fitness. Only visits by large native bees had discernible effects on recipient fecundity, and, overall, fecundity was not limited by visitation. Maternal plants bearing large-petalled flowers produced fewer flowers during the experiment, reducing their total seed production. In these small populations, postpollination processes (at least in part, compatibility) significantly influenced male and female reproductive success. Variation in pollinator pools occurring on both spatial and temporal scales may act to preserve genetic variation for floral traits in this species.
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Affiliation(s)
- Maureen Stanton
- Department of Botany, University of California, Davis, CA, 95616, USA
| | - Helen J Young
- Department of Botany, University of California, Davis, CA, 95616, USA
| | - Norman C Ellstrand
- Department of Botany and Plant Sciences and Program in Genetics, University of California, Riverside, CA, 92521, USA
| | - Janet M Clegg
- Department of Botany and Plant Sciences and Program in Genetics, University of California, Riverside, CA, 92521, USA
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26
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Hallett AC, Mitchell RJ, Chamberlain ER, Karron JD. Pollination success following loss of a frequent pollinator: the role of compensatory visitation by other effective pollinators. AOB PLANTS 2017; 9:plx020. [PMID: 28798863 PMCID: PMC5544916 DOI: 10.1093/aobpla/plx020] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Accepted: 05/25/2017] [Indexed: 05/31/2023]
Abstract
Pollinator abundance is declining worldwide and may lower the quantity and quality of pollination services to flowering plant populations. Loss of an important pollinator is often assumed to reduce the amount of pollen received by stigmas of a focal species (pollination success), yet this assumption has rarely been tested experimentally. The magnitude of the effect, if any, may depend on the relative efficiency of the remaining pollinators, and on whether the loss of one pollinator leads to changes in visitation patterns by other pollinators. To explore how a change in pollinator composition influences pollination of Asclepias verticillata, we excluded bumble bees from plots in large and small populations of this milkweed species. We then quantified pollinator visitation rates, pollen export and pollen receipt for control plots and for plots where bumble bees were experimentally excluded. We found that exclusion of bumble bees did not reduce pollen receipt by A. verticillata flowers. Visitation by Polistes wasps increased markedly following bumble bee exclusion, both in small populations (186 % increase) and in large populations (400 % increase). Because Polistes wasps were as efficient as bumble bees at pollen transfer, increased wasp visitation offset lost bumble bee pollination services. Thus, loss of a frequent pollinator will not necessarily lead to a decline in pollination success. When pollinator loss is followed by a shift in the composition and abundance of remaining pollinators, pollination success will depend on the net change in the quantity and quality of pollination services.
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Affiliation(s)
- Allysa C. Hallett
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
| | | | - Evan R. Chamberlain
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
| | - Jeffrey D. Karron
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
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27
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Parker AJ, Williams NM, Thomson JD. Specialist pollinators deplete pollen in the spring ephemeral wildflower Claytonia virginica. Ecol Evol 2016; 6:5169-77. [PMID: 27551374 PMCID: PMC4984495 DOI: 10.1002/ece3.2252] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Revised: 05/09/2016] [Accepted: 05/16/2016] [Indexed: 11/21/2022] Open
Abstract
Pollinators that collect pollen – and specifically, pollen‐specialist bees – are often considered to be the best pollinators of a (host) plant. Although pollen collectors and pollen specialists often benefit host plants, especially in the pollen that they deliver (their pollination “effectiveness”), they can also exact substantial costs because they are motivated to collect as much pollen as possible, reducing the proportion of pollen removed that is subsequently delivered to stigmas (their pollination “efficiency”). From the plant perspective, pollen grains that do not pollinate conspecific stigmas are “wasted”, and potentially costly. We measured costs and benefits of nectar‐collecting, pollen‐collecting, and pollen‐specialist pollinator visitation to the spring ephemeral Claytonia virginica. Visits by the pollen‐specialist bee Andrena erigeniae depleted pollen quickly and thoroughly. Although all pollinators delivered roughly the same number of grains, the pollen specialist contributed most to C. virginica pollen delivery because of high visitation rates. However, the pollen specialist also removed a large number of grains; this removal may be especially costly because it resulted in the depletion of pollen grains in C. virginica populations. While C. virginica appears to rely on pollen transfer by the pollen specialist in these populations, nectar‐collecting visitors could provide the same benefit at a lower cost if their visitation rates increased. Pollen depletion affects a pollinator's value to plants, but is frequently overlooked. If they lower the effectiveness of future floral visitors, visits by A. erigeniae females to C. virginica may be more detrimental than beneficial compared to other pollinators and may, in some circumstances, reduce plant fitness rather than increase it. Therefore, A. erigeniae and C. virginica may vary in their degree of mutualism depending on the ecological context.
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Affiliation(s)
- Alison J Parker
- University of Toronto 25 Harbord Street Toronto ON M5S 3G5 Canada
| | - Neal M Williams
- University of California-Davis 380 Briggs Hall One Shields Ave. Davis California 95616
| | - James D Thomson
- University of Toronto 25 Harbord Street Toronto ON M5S 3G5 Canada
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28
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Anderson B, Pauw A, Cole WW, Barrett SCH. Pollination, mating and reproductive fitness in a plant population with bimodal floral-tube length. J Evol Biol 2016; 29:1631-42. [PMID: 27206242 DOI: 10.1111/jeb.12899] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 05/15/2016] [Accepted: 05/16/2016] [Indexed: 01/19/2023]
Abstract
Mating patterns and natural selection play important roles in determining whether genetic polymorphisms are maintained or lost. Here, we document an atypical population of Lapeirousia anceps (Iridaceae) with a bimodal distribution of floral-tube length and investigate the reproductive mechanisms associated with this pattern of variation. Flowers were visited exclusively by the long-proboscid fly Moegistorhynchus longirostris (Nemestrinidae), which exhibited a unimodal distribution of proboscis length and displayed a preference for long-tubed phenotypes. Despite being visited by a single pollinator species, allozyme markers revealed significant genetic differentiation between open-pollinated progeny of long- and short-tubed phenotypes suggesting mating barriers between them. We obtained direct evidence for mating barriers between the floral-tube phenotypes through observations of pollinator foraging, controlled hand pollinations and measurements of pollen competition and seed set. Intermediate tube-length phenotypes produced fewer seeds in the field than either long- or short-tubed phenotypes. Although floral-tube length bimodality may not be a stable state over long timescales, reproductive barriers to mating and low 'hybrid' fitness have the potential to contribute to the maintenance of this state in the short term.
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Affiliation(s)
- B Anderson
- Department of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa
| | - A Pauw
- Department of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa
| | - W W Cole
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
| | - S C H Barrett
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
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29
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Ogilvie JE, Thomson JD. Site fidelity by bees drives pollination facilitation in sequentially blooming plant species. Ecology 2016; 97:1442-51. [DOI: 10.1890/15-0903.1] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Jane E. Ogilvie
- Department of Ecology and Evolutionary Biology; University of Toronto; 25 Harbord Street Toronto Ontario M5S 3G5 Canada
- The Rocky Mountain Biological Laboratory; Post Office Box 519 Crested Butte Colorado 81224-0519 USA
| | - James D. Thomson
- Department of Ecology and Evolutionary Biology; University of Toronto; 25 Harbord Street Toronto Ontario M5S 3G5 Canada
- The Rocky Mountain Biological Laboratory; Post Office Box 519 Crested Butte Colorado 81224-0519 USA
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30
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Floral Nectar: Pollinator Attraction or Manipulation? Trends Ecol Evol 2016; 31:339-341. [PMID: 26987770 DOI: 10.1016/j.tree.2016.02.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Revised: 02/10/2016] [Accepted: 02/11/2016] [Indexed: 11/21/2022]
Abstract
The literature suggests that floral nectar acts principally to attract pollinator visitation (and/or revisitation), thereby enhancing plant reproductive success. However, floral nectar also manipulates pollinator behaviour during and immediately following plant visits, affecting pollen transfer, and plant reproduction. I argue that floral nectar should really be viewed as a pollinator manipulant rather than attractant, thus potentially explaining why its concentration is not generally high and why it decreases with increasing pollinator body size. Otherwise, such patterns may remain mysterious and unexplained.
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31
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Gillespie S, Long R, Williams N. Indirect Effects of Field Management on Pollination Service and Seed Set in Hybrid Onion Seed Production. JOURNAL OF ECONOMIC ENTOMOLOGY 2015; 108:2511-2517. [PMID: 26470371 DOI: 10.1093/jee/tov225] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 07/09/2015] [Indexed: 06/05/2023]
Abstract
Pollination in crops, as in native ecosystems, is a stepwise process that can be disrupted at any stage. Healthy pollinator populations are critical for adequate visitation, but pollination still might fail if crop management interferes with the attraction and retention of pollinators. Farmers must balance the direct benefits of applying insecticide and managing irrigation rates against their potential to indirectly interfere with the pollination process. We investigated these issues in hybrid onion seed production, where previous research has shown that high insecticide use reduces pollinator attraction. We conducted field surveys of soil moisture, nectar production, pollinator visitation, pollen-stigma interactions, and seed set at multiple commercial fields across 2 yr. We then examined how management actions, such as irrigation rate (approximated by soil moisture), or insecticide use could affect the pollination process. Onions produced maximum nectar at intermediate soil moisture, and high nectar production attracted more pollinators. Insecticide use weakly affected pollinator visitation, but when applied close to bloom reduced pollen germination and pollen tube growth. Ultimately, neither soil moisture nor insecticide use directly affected seed set, but the high correlation between pollinator visitation and seed set suggests that crop management will ultimately affect yields via indirect effects on the pollination process.
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Affiliation(s)
- Sandra Gillespie
- Department of Biology, Simon Fraser University, 8888 University Drive, Burnaby B.C. Canada, V5A 1S6.
| | - Rachael Long
- Department of Entomology, University of California, Davis, CA 95616
| | - Neal Williams
- University of California Cooperative Extension, Yolo County, CA 95616
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32
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Jogesh T, Stanley MC, Berenbaum MR. Evolution of tolerance in an invasive weed after reassociation with its specialist herbivore. J Evol Biol 2015; 27:2334-46. [PMID: 25417738 DOI: 10.1111/jeb.12469] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 07/30/2014] [Accepted: 08/05/2014] [Indexed: 11/26/2022]
Abstract
The interaction between the European wild parsnip Pastinaca sativa and its coevolved florivore the parsnip webworm Depressaria pastinacella, established in North America for over 150 years, has resulted in evolution of local chemical phenotype matching. The recent invasion of New Zealand by webworms, exposing parsnips there to florivore selection for the first time, provided an opportunity to assess rates of adaptive response in a real-time experiment. We planted reciprocal common gardens in the USA and NZ with seeds from (1) US populations with a long history of webworm association; (2) NZ populations that had never been infested and (3) NZ populations infested for 3 years (since 2007) or 6 years (since 2004). We measured impacts of florivory on realized fitness, reproductive effort and pollination success and measured phenotypic changes in infested NZ populations relative to uninfested NZ populations to determine whether rapid adaptive evolution in response to florivory occurred. Irrespective of country of origin or location, webworms significantly reduced plant fitness. Webworms reduced pollination success in small plants but not in larger plants. Although defence chemistry remained unchanged, plants in infested populations were larger after 3-6 years of webworm florivory. As plant size is a strong predictor of realized fitness, evolution of large size as a component of florivore tolerance may occur more rapidly than evolution of enhanced chemical defence.
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Affiliation(s)
- T Jogesh
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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Bee- to bird-pollination shifts in Penstemon: effects of floral-lip removal and corolla constriction on the preferences of free-foraging bumble bees. Evol Ecol 2015. [DOI: 10.1007/s10682-014-9716-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Liao WJ, Harder LD. Consequences of Multiple Inflorescences and Clonality for Pollinator Behavior and Plant Mating. Am Nat 2014; 184:580-92. [DOI: 10.1086/678117] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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The Variability of Selected Features of Gladiolus imbricatus L. in Relation to Successive Stages of Meadow Communities Following the Mowing Cessation. POLISH JOURNAL OF ECOLOGY 2014. [DOI: 10.3161/104.062.0210] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Jersáková J, Jürgens A, Šmilauer P, Johnson SD. The evolution of floral mimicry: identifying traits that visually attract pollinators. Funct Ecol 2012. [DOI: 10.1111/j.1365-2435.2012.02059.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jana Jersáková
- University of South Bohemia; Česke Budejovice Czech Republic
- School of Life Sciences; University of KwaZulu-Natal; Pietermaritzburg South Africa
| | - Andreas Jürgens
- School of Life Sciences; University of KwaZulu-Natal; Pietermaritzburg South Africa
| | - Petr Šmilauer
- University of South Bohemia; Česke Budejovice Czech Republic
| | - Steven D. Johnson
- School of Life Sciences; University of KwaZulu-Natal; Pietermaritzburg South Africa
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Duffy KJ, Johnson SD. Effects of pollen reward removal on fecundity in a self-incompatible hermaphrodite plant. PLANT BIOLOGY (STUTTGART, GERMANY) 2011; 13:556-60. [PMID: 21489109 DOI: 10.1111/j.1438-8677.2011.00445.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The pollen of hermaphrodite plants is often utilised by flower-visiting animals. While pollen production has obvious benefits for plant male fitness, its consequences for plant female fitness, especially in self-incompatible hermaphrodite species, are less certain. Pollen production could either enhance seed production though increased pollinator attraction, or reduce it if ovules are discounted by deposition of self pollen, as can occur in species with late-acting self-incompatibility. To test the effects of pollen reward provision on female fitness, we artificially emasculated flowers in two populations of the succulent Aloe maculata (Asphodelaceae), which has a late-acting self-incompatibility system, over the course of its flowering period. Flowers of this species are visited by sunbirds (for nectar) and native bees (for pollen and nectar). We measured floral visitation rates, floral rejection rates, pollen deposition on stigmas and fruit and seed set in both emasculated and non-emasculated plants. We found that flowers of emasculated plants suffered reduced visitation and increased rejection (arrival without visitation) by bees, but not by sunbirds; had fewer pollen grains deposited on stigmas and showed an overall decrease in fruit set and seed set. Rates of seed abortion were, however, greatly reduced in emasculated flowers. This study shows that pollen rewards can be important for seed set, even in self-incompatible plants, which have been assumed to rely on nectar rewards for pollinator attraction. Seed abortion was, however, increased by pollen production, a result that highlights the complexity of selection on pollen production in hermaphrodite flowers.
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Affiliation(s)
- K J Duffy
- School of Biological and Conservation Sciences, University of KwaZulu-Natal, Scottsville, Pietermaritzburg, South Africa.
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Torices R, Méndez M. Influence of inflorescence size on sexual expression and female reproductive success in a monoecious species. PLANT BIOLOGY (STUTTGART, GERMANY) 2011; 13 Suppl 1:78-85. [PMID: 21134090 DOI: 10.1111/j.1438-8677.2009.00292.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Sex allocation theory forecasts that larger plant size may modify the balance in fitness gain in both genders, leading to uneven optimal male and female allocation. This reasoning can be applied to flowers and inflorescences, because the increase in flower or inflorescence size can differentially benefit different gender functions, and thus favour preferential allocation to specific floral structures. We investigated how inflorescence size influenced sexual expression and female reproductive success in the monoecious Tussilago farfara, by measuring patterns of biomass, and N and P allocation. Inflorescences of T. farfara showed broad variation in sex expression and, according to expectations, allocation to different sexual structures showed an allometric pattern. Unexpectedly, two studied populations had a contrasting pattern of sex allocation with an increase in inflorescence size. In a shaded site, larger inflorescences were female-biased and had disproportionately more allocation to attraction structures; while in an open site, larger inflorescences were male-biased. Female reproductive success was higher in larger, showier inflorescences. Surprisingly, male flowers positively influenced female reproductive success. These allometric patterns were not easily interpretable as a result of pollen limitation when naïvely assuming an unequivocal relationship between structure and function for the inflorescence structures. In this and other Asteraceae, where inflorescences are the pollination unit, both male and female flowers can play a role in pollinator attraction.
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Affiliation(s)
- R Torices
- Area de Biodiversidad y Conservación, Universidad Rey Juan Carlos, Móstoles (Madrid), Spain.
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Durisko Z, Shipp L, Dukas R. Effects of Experience on Short- and Long-term Foraging Performance in Bumblebees. Ethology 2010. [DOI: 10.1111/j.1439-0310.2010.01842.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Bayesian foraging in patchy environments requires that foragers have information about the distribution of resources among patches (prior information), either set by natural selection or learned from past experience. We test the hypothesis that bumblebee foragers can rapidly learn prior information from past experience in two very different experimental environments. In the high-variance environment (patches of low and high quality), stochastic optimality models predicted that finding rewards should sometimes sharply increase an optimal forager's tendency to stay in a patch (an incremental response), whereas in the uniform environment, finding rewards should always decrease the tendency to stay (a decremental response). We use Cox regression models to show that, in a matter of hours, bees learned to match both predicted responses, resulting in a reward intake rate that averaged 80% of the predicted maximum. Following training in either environment, bees' adaptive behavior carried over to a common test environment, thus confirming the influence of memorized prior information. Although Bayesian foraging by learning is often presumed, this study is the first to clearly isolate the adaptive use of a learned prior expectation. More generally, it highlights the remarkable adaptive plasticity of an important generalist pollinator and agent of selection.
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Affiliation(s)
- Jay M Biernaskie
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario M5S 3B2, Canada.
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Ohashi K, Thomson JD. Trapline foraging by pollinators: its ontogeny, economics and possible consequences for plants. ANNALS OF BOTANY 2009; 103:1365-78. [PMID: 19398446 PMCID: PMC2701764 DOI: 10.1093/aob/mcp088] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
BACKGROUND Trapline foraging (repeated sequential visits to a series of feeding locations) has been often observed in pollinators collecting nectar or pollen from flowers. Although field studies on bumble-bees and hummingbirds have clarified fundamental aspects of this behaviour, trapline foraging still poses several difficult questions from the perspectives of both animals and plants. These questions include whether and how traplining improves foraging performance, how animals develop traplines with accumulating foraging experience, and how traplining affects pollen flow or plant reproduction. SCOPE First, we review our previous work performed by using computer simulations and indoor flight-cage experiments with bumble-bees foraging from arrays of automated feeders. Our findings include the following: (1) traplining benefits foragers that are competing for resources that replenish in a decelerating way, (2) traplining is a learned behaviour that develops over a period of hours and (3) the establishment of traplines could be hampered by spatial configuration of plants such as zigzags. Second, using a simulation model linking pollinator movement and pollen transfer, we consider how service by pollinators with different foraging patterns (searchers or trapliners) would affect pollen flow. Traplining increases mating distance and mate diversity, and reduces 'iterogamy' (self-pollination caused by return visits) at the population level. Furthermore, increased visitation rates can have opposite effects on the reproductive success of a plant, depending on whether the visitors are traplining or searching. Finally, we discuss possible consequences of traplining for plants in the light of new experimental work and modelling. CONCLUSIONS We suggest that trapline foraging by pollinators increases variation among plant populations in genetic diversity, inbreeding depression and contributions of floral traits to plant fitness, which should in turn affect the rates and directions of floral evolution. More theoretical and empirical studies are needed to clarify possible outcomes of such a neglected side of pollination.
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Kaczorowski RL, Juenger TE, Holtsford TP. Heritability and correlation structure of nectar and floral morphology traits in Nicotiana alata. Evolution 2008; 62:1738-1750. [PMID: 18410534 DOI: 10.1111/j.1558-5646.2008.00400.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The heritability and genetic basis of nectar traits have been rarely studied in the field, where plants are exposed to environmental factors that could mask underlying genetic effects. Heritabilities and variance components were estimated for nectar and morphological traits of Nicotiana alata, using a partial diallel design. The main experiment was conducted in a Missouri experimental garden using a randomized block design with three plant density treatments, whereas a smaller experiment was conducted near native Brazil habitat to compare the environmental variance in traits between Missouri and Brazil. Significant heritability was detected for nectar volume and energy content, and for corolla tube length. Phenotypic correlations were significant between all traits investigated, whereas significant genetic correlations were only found between nectar volume and energy and between corolla limb width and mouth diameter. There were no significant family-by-density interactions detected in the Missouri field environment. All traits differed significantly between Missouri and Brazil environments, but significant genetic by environment (G x E) interactions between Missouri and Brazil were detected for only one trait. This study shows that nectar traits can be heritable despite considerable environmental variation.
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Affiliation(s)
- Rainee L Kaczorowski
- University of Missouri-Columbia, Division of Biological Sciences, 105 Tucker Hall, Columbia, Missouri 65211
- E-mail:
| | - Thomas E Juenger
- University of Texas at Austin, Section of Integrative Biology, 1 University Station, C0930 Austin, Texas 78712
| | - Timothy P Holtsford
- University of Missouri-Columbia, Division of Biological Sciences, 105 Tucker Hall, Columbia, Missouri 65211
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Ohashi K, Leslie A, Thomson JD. Trapline foraging by bumble bees: V. Effects of experience and priority on competitive performance. Behav Ecol 2008. [DOI: 10.1093/beheco/arn048] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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KEVAN PETERG, EISIKOWITCH D, AMBROSE JOHND, KEMP JAMESR. Cryptic dioecy and insect pollination in Rosa setigera Michx. (Rosaceae), a rare plant of Carolinian Canada. Biol J Linn Soc Lond 2008. [DOI: 10.1111/j.1095-8312.1990.tb00537.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kropf M, Renner SS. Pollinator-mediated selfing in two deceptive orchids and a review of pollinium tracking studies addressing geitonogamy. Oecologia 2007; 155:497-508. [PMID: 18060434 DOI: 10.1007/s00442-007-0919-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2006] [Accepted: 11/05/2007] [Indexed: 11/27/2022]
Affiliation(s)
- Matthias Kropf
- Institute of Botany, University of Natural Resources and Applied Life Sciences, Gregor Mendel Strasse 33, 1180, Vienna, Austria
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Benitez-Vieyra S, Hempel de Ibarra N, Wertlen AM, Cocucci AA. How to look like a mallow: evidence of floral mimicry between Turneraceae and Malvaceae. Proc Biol Sci 2007; 274:2239-48. [PMID: 17623635 PMCID: PMC2287375 DOI: 10.1098/rspb.2007.0588] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abundant, many-flowered plants represent reliable and rich food sources for animal pollinators, and may even sustain guilds of specialized pollinators. Contrastingly, rare plants need alternative strategies to ensure pollinators' visitation and faithfulness. Flower mimicry, i.e. the sharing of a similar flower colour and display pattern by different plant species, is a means by which a rare species can exploit a successful model and increase its pollination services. The relationship between two or more rewarding flower mimic species, or Müllerian mimicry, has been proposed as mutualistic, in contrast to the unilaterally beneficial Batesian floral mimicry. In this work, we show that two different geographical colour phenotypes of Turnera sidoides ssp. pinnatifida resemble co-flowering Malvaceae in colour as seen by bees' eyes, and that these pollinators do not distinguish between them when approaching flowers in choice tests. Main pollinators of T. sidoides are bees specialized for collecting pollen in Malvaceae. We demonstrate that the similarity between at least one of the geographical colour phenotypes of T. sidoides and co-flowering Malvaceae is adaptive, since the former obtains more pollination services when growing together with its model than when growing alone. Instead of the convergent evolution pattern attributed to Müllerian mimicry, our data rather suggest an advergent evolution pattern, because only T. sidoides seems to have evolved to be more similar to its malvaceous models.
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Affiliation(s)
- Santiago Benitez-Vieyra
- Instituto Multidisciplinario de Biología Vegetal (CONICET-U. N. Córdoba), CC 495, CP 5000, Córdoba, Argentina.
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MAKINO TT, SAKAI S. Experience changes pollinator responses to floral display size: from size-based to reward-based foraging. Funct Ecol 2007. [DOI: 10.1111/j.1365-2435.2007.01293.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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MAKINO TT, OHASHI K, SAKAI S. How do floral display size and the density of surrounding flowers influence the likelihood of bumble bee revisitation to a plant? Funct Ecol 2007. [DOI: 10.1111/j.1365-2435.2006.01211.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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