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Robles C, Romero-Egea V, Traveset A, Ruiz de Ybáñez R, Hervías-Parejo S. Vertebrates can be more important pollinators than invertebrates on islands: the case of Malva (=Lavatera) arborea L. AOB PLANTS 2024; 16:plae010. [PMID: 38497048 PMCID: PMC10944019 DOI: 10.1093/aobpla/plae010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Accepted: 02/23/2024] [Indexed: 03/19/2024]
Abstract
Premise of the study: On islands, flowering plants tend to be more generalist in their pollination needs, as insects (the main pollinators of flowering plants) are underrepresented in these ecosystems compared to the mainland. In addition, some vertebrate species that are typically insectivorous or granivorous on the mainland are forced to broaden their diet and consume other resources such as nectar or pollen on the islands. The shrub Malva arborea, with its large and colourful flowers, attracts different groups of potential pollinators. This study aimed to compare the effectiveness of vertebrates versus insects in an insular population of M. arborea and to investigate its reproductive system. Methods: For three groups of taxa (insects, birds and lizards), we assessed the two components of pollination effectiveness: (i) the quantitative component (i.e. number of visits and number of flowers contacted) through direct observations of flowers; and (ii) the qualitative component (fruit and seed set, number and size of seeds and proportion of seedling emergence) through pollinator exclusion experiments. Key results: Vertebrates (birds and lizards) were quantitatively the most effective pollinators, followed by insects. However, when all three groups visited the flowers, fruit and seed set were higher than when any of them were excluded. We also found that M. arborea has hermaphrodite flowers and is able to reproduce by autogamy, although less efficiently than when pollinated by animals. Conclusions: Both vertebrates and insects play an important role in the reproduction of M. arborea. Although the plant does not need pollinators to produce seeds, its reproductive success increases when all pollinators are allowed to visit the flowers. Besides providing new information on M. arborea, these findings may help to better understand the role of different pollinator groups in the reproduction of other plant species, especially on islands where the co-occurrence of vertebrate and invertebrate pollination in the same plant species is usual.
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Affiliation(s)
- Cristina Robles
- Department of Animal Health, Campus de Espinardo, University of Murcia, 30100 Murcia, Spain
| | - Víctor Romero-Egea
- Department of Animal Health, Campus de Espinardo, University of Murcia, 30100 Murcia, Spain
| | - Anna Traveset
- Mediterranean Institute for Advanced Studies (IMEDEA, UIB-CSIC), Global Change Research group, Miquel Marquès 21, 07190 Esporles, Spain
| | - Rocío Ruiz de Ybáñez
- Department of Animal Health, Campus de Espinardo, University of Murcia, 30100 Murcia, Spain
| | - Sandra Hervías-Parejo
- Mediterranean Institute for Advanced Studies (IMEDEA, UIB-CSIC), Global Change Research group, Miquel Marquès 21, 07190 Esporles, Spain
- Centre for Functional Ecology (CFE-UC), Community Ecology Lab, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3004-531 Coimbra, Portugal
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2
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Travis DJ, Kohn JR. Honeybees ( Apis mellifera) decrease the fitness of plants they pollinate. Proc Biol Sci 2023; 290:20230967. [PMID: 37357853 PMCID: PMC10291720 DOI: 10.1098/rspb.2023.0967] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 06/01/2023] [Indexed: 06/27/2023] Open
Abstract
Most flowering plants require animal pollination and are visited by multiple pollinator species. Historically, the effects of pollinators on plant fitness have been compared using the number of pollen grains they deposit, and the number of seeds or fruits produced following a visit to a virgin flower. While useful, these methods fail to consider differences in pollen quality and the fitness of zygotes resulting from pollination by different floral visitors. Here we show that, for three common native self-compatible plants in Southern California, super-abundant, non-native honeybees (Apis mellifera L.) visit more flowers on an individual before moving to the next plant compared with the suite of native insect visitors. This probably increases the transfer of self-pollen. Offspring produced after honeybee pollination have similar fitness to those resulting from hand self-pollination and both are far less fit than those produced after pollination by native insects or by cross-pollination. Because honeybees often forage methodically, visiting many flowers on each plant, low offspring fitness may commonly result from honeybee pollination of self-compatible plants. To our knowledge, this is the first study to directly compare the fitness of offspring resulting from honeybee pollination to that of other floral visitors.
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Affiliation(s)
- Dillon J. Travis
- Department of Ecology, Behavior, and Evolution, School of Biological Sciences, University of California San Diego, San Diego, CA 92093, USA
| | - Joshua R. Kohn
- Department of Ecology, Behavior, and Evolution, School of Biological Sciences, University of California San Diego, San Diego, CA 92093, USA
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3
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Sinclair BJ. An annotated checklist of the Diptera of the Galápagos Archipelago (Ecuador). Zootaxa 2023; 5283:1-102. [PMID: 37518751 DOI: 10.11646/zootaxa.5283.1.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Indexed: 08/01/2023]
Abstract
The Diptera fauna of the Galápagos Archipelago is updated and an annotated checklist is presented. Currently 50 families, 207 genera, and a minimum of 324 species are recorded from the islands. Approximately 107 species are considered to have arrived on the Galápagos Islands through human introductions, an estimated 101 species are considered endemic, 42 species have naturally colonized the islands from mainland Americas, 21 species are either introduced or arrived naturally and 53 species remain unidentified. The following new combination is proposed: Chrysanthrax primitivus (Walker) is moved to Hemipenthes Loew as H. primitivus (Walker) comb. nov. All references to the Galápagos taxonomic literature are included, known island species distributions listed and general remarks on the biology of many species are provided.
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Affiliation(s)
- Bradley J Sinclair
- Canadian Food Inspection Agency; K.W. Neatby Bldg.; C.E.F.; 960 Carling Ave.; Ottawa; ON; Canada K1A 0C6; Canadian National Collection of Insects; Arachnids and Nematodes; Agriculture and Agri-Food Canada; K.W. Neatby Bldg.; C.E.F.; 960 Carling Ave.; Ottawa; ON; Canada K1A 0C6.
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4
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Andrews CE, Anderson SH, van der Walt K, Thorogood R, Ewen JG. Evaluating the success of functional restoration after reintroduction of a lost avian pollinator. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2022; 36:e13892. [PMID: 35171538 PMCID: PMC9545379 DOI: 10.1111/cobi.13892] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 11/19/2021] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
Conservation translocation is a common method for species recovery, for which one increasingly frequent objective is restoring lost ecological functions to promote ecosystem recovery. However, few conservation translocation programs explicitly state or monitor function as an objective, limiting the ability to test assumptions, learn from past efforts, and improve management. We evaluated whether translocations of hihi (Notiomystis cincta), a threatened New Zealand passerine, achieved their implicit objective of restoring lost pollination function. Through a pollinator-exclusion experiment, we quantified, with log response ratios (lnR), the effects of birds on fruit set and seed quality in hangehange (Geniostoma ligustrifolium), a native flowering shrub. We isolated the contributions of hihi by making comparisons across sites with and without hihi. Birds improved fruit set more at sites without hihi (lnR = 1.27) than sites with hihi (lnR = 0.50), suggesting other avian pollinators compensated for and even exceeded hihi contributions to fruit set. Although birds improved seed germination only at hihi sites (lnR = 0.22-0.41), plants at sites without hihi had germination rates similar to hihi sites because they produced 26% more filled seeds, regardless of pollination condition. Therefore, although our results showed hihi improved seed quality, they also highlighted the complexity of ecological functions. When an important species is lost, ecosystems may be able to achieve similar function through different means. Our results underscore the importance of stating and monitoring the ecological benefits of conservation translocations when functional restoration is a motivation to ensure these programs are achieving their objectives.
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Affiliation(s)
- Caitlin E. Andrews
- Department of ZoologyUniversity of CambridgeCambridgeUK
- Institute of ZoologyZoological Society of LondonLondonUK
| | | | - Karin van der Walt
- Ōtari Native Botanic Garden and Wilton's Bush ReserveWellingtonNew Zealand
| | - Rose Thorogood
- Department of ZoologyUniversity of CambridgeCambridgeUK
- Helsinki Institute of Life Science (HiLIFE)University of HelsinkiHelsinkiFinland
- Research Program in Organismal and Evolutionary Biology, Faculty of Biological and Environmental SciencesUniversity of HelsinkiHelsinkiFinland
| | - John G. Ewen
- Institute of ZoologyZoological Society of LondonLondonUK
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5
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Bergamo PJ, Freitas L, Sazima M, Wolowski M. Pollinator-mediated facilitation alleviates pollen limitation in a plant-hummingbird network. Oecologia 2022; 198:205-217. [PMID: 35067800 DOI: 10.1007/s00442-021-05095-3] [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: 06/11/2021] [Accepted: 12/12/2021] [Indexed: 10/19/2022]
Abstract
Facilitation and competition among plants sharing pollinators have contrasting consequences for plant fitness. However, it is unclear whether pollinator-mediated facilitation and competition may affect pollen limitation (potential contribution of pollination to fitness) in pollination networks. Here, we investigated how pollinator sharing affects pollen limitation in a tropical hummingbird-pollinated community marked by facilitation. We employed indices describing how much a plant species potentially affects the pollination of other co-flowering species through shared pollinators (acting degree) and is affected by other co-flowering species (target degree) within the plant-hummingbird network. Since facilitation often increases pollination quantity but not necessarily quality, we expected both indices to be associated with reductions in pollen limitation estimates that depend on pollination quantity (fruit set and seed number) rather than estimates more strictly related to quality (seed weight and germination). We found that both indices were associated with reductions in pollen limitation only for seed weight and germination. Thus, facilitation occurred via qualitative estimates of pollen limitation. Our results suggest that facilitation may enhance plant fitness estimates even if quantitative components of plant fecundity are already saturated. Overall, we showed that pollinator-mediated indirect effects in a multispecies context are important drivers of plant fitness estimates with consequences for coexistence in diverse communities.
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Affiliation(s)
- Pedro Joaquim Bergamo
- Programa de Pós-Graduação em Ecologia, Universidade Estadual de Campinas, Campinas, Bertrand Russel Av, PO Box 6109, Campinas, Brazil. .,Rio de Janeiro Botanical Garden, Rio de Janeiro, Brazil.
| | | | - Marlies Sazima
- Plant Biology Department, Institute of Biology, University of Campinas, Campinas, Brazil
| | - Marina Wolowski
- Institute of Natural Sciences, Federal University of Alfenas, Alfenas, Brazil
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6
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Parent CE, Peck SB, Causton CE, Roque-Albelo L, Lester PJ, Bulgarella M. Polistes versicolor (Hymenoptera: Vespidae), an Introduced Wasp in the Galapagos Islands: Its Life Cycle and Ecological Impact. ENVIRONMENTAL ENTOMOLOGY 2020; 49:1480-1491. [PMID: 32978630 DOI: 10.1093/ee/nvaa110] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Indexed: 06/11/2023]
Abstract
The yellow paper wasp, Polistes versicolor (Olivier) was first recorded in the Galapagos archipelago in 1988. Its life cycle and ecological impacts were studied on two islands 11 yr after it was first discovered. This invasive wasp adapted quickly and was found in most environments. Colony counts and adult wasp monitoring showed a strong preference for drier habitats. Nest activities were seasonally synchronized, nest building followed the rains in the hot season (typically January-May), when insect prey increases, and peaked as temperature and rains started to decline. Next, the number of adult wasps peaked during the cool season when there is barely any rain in the drier zones. In Galapagos, almost half of the prey loads of P. versicolor were lepidopteran larvae, but wasps also carried spiders, beetles, and flies back to the colonies. An estimated average of 329 mg of fresh insect prey was consumed per day for an average colony of 120-150 wasp larvae. The wasps preyed upon native and introduced insects, but likely also affect insectivorous vertebrates as competitors for food. Wasps may also compete with native pollinators as they regularly visited flowers to collect nectar, and have been recorded visiting at least 93 plant species in Galapagos, including 66 endemic and native plants. Colonies were attacked by a predatory moth, Taygete sphecophila (Meyrick) (Lepidoptera: Autostichidae), but colony development was not arrested. High wasp numbers also affect the activities of residents and tourists. A management program for this invasive species in the archipelago is essential.
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Affiliation(s)
- Christine E Parent
- Department of Biological Sciences and Institute for Bioinformatics and Evolutionary Studies, University of Idaho, Perimeter MS, Moscow, ID
| | - Stewart B Peck
- Department of Entomology, Research and Collections Division, Canadian Museum of Nature, Station D, Ottawa ON, Canada
| | - Charlotte E Causton
- Charles Darwin Research Station, Charles Darwin Foundation, Puerto Ayora, Santa Cruz Island, Galápagos Islands, Ecuador
| | - Lázaro Roque-Albelo
- Charles Darwin Research Station, Charles Darwin Foundation, Puerto Ayora, Santa Cruz Island, Galápagos Islands, Ecuador
| | - Philip J Lester
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Mariana Bulgarella
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
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7
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Hervías-Parejo S, Tur C, Heleno R, Nogales M, Timóteo S, Traveset A. Species functional traits and abundance as drivers of multiplex ecological networks: first empirical quantification of inter-layer edge weights. Proc Biol Sci 2020; 287:20202127. [PMID: 33234084 DOI: 10.1098/rspb.2020.2127] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Many vertebrate species act as both plant pollinators and seed-dispersers, thus interconnecting these processes, particularly on islands. Ecological multilayer networks are a powerful tool to explore interdependencies between processes; however, quantifying the links between species engaging in different types of interactions (i.e. inter-layer edges) remains a great challenge. Here, we empirically measured inter-layer edge weights by quantifying the role of individually marked birds as both pollinators and seed-dispersers of Galápagos plant species over an entire year. Although most species (80%) engaged in both functions, we show that only a small proportion of individuals actually linked the two processes, highlighting the need to further consider intra-specific variability in individuals' functional roles. Furthermore, we found a high variation among species in linking both processes, i.e. some species contribute more than others to the modular organization of the multilayer network. Small and abundant species are particularly important for the cohesion of pollinator seed-dispersal networks, demonstrating the interplay between species traits and neutral processes structuring natural communities.
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Affiliation(s)
- S Hervías-Parejo
- Oceanography and Global Change Department. C/ Miquel Marqués 21, Institut Mediterrani d'Estudis Avançats IMEDEA (CSIC-UIB), E07190-Esporles, Mallorca, Balearic Islands, Spain
| | - C Tur
- Oceanography and Global Change Department. C/ Miquel Marqués 21, Institut Mediterrani d'Estudis Avançats IMEDEA (CSIC-UIB), E07190-Esporles, Mallorca, Balearic Islands, Spain
| | - R Heleno
- Department of Life Sciences, University of Coimbra, Centre for Functional Ecology, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal
| | - M Nogales
- Instituto de Productos Naturales y Agrobiologia (IPNA-CSIC), Island Ecology and Evolution Research Group. C/Astrofísico Fco. Sánchez 3, 38206 La Laguna, Tenerife, Canaries, Spain
| | - S Timóteo
- Department of Life Sciences, University of Coimbra, Centre for Functional Ecology, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal
| | - A Traveset
- Oceanography and Global Change Department. C/ Miquel Marqués 21, Institut Mediterrani d'Estudis Avançats IMEDEA (CSIC-UIB), E07190-Esporles, Mallorca, Balearic Islands, Spain
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8
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Wang X, Wen M, Qian X, Pei N, Zhang D. Plants are visited by more pollinator species than pollination syndromes predicted in an oceanic island community. Sci Rep 2020; 10:13918. [PMID: 32811900 PMCID: PMC7434763 DOI: 10.1038/s41598-020-70954-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/03/2020] [Indexed: 11/09/2022] Open
Abstract
The pollination syndrome concept has provided powerful utility in understanding the evolution and adaptation of floral traits. However, the utility of this conception has been questioned on the grounds that flowers usually attract a broader spectrum of visitors than one might expect. Furthermore, the relationship between plant specialization and floral traits is poorly understood. Here, we examined the applicability of using the pollination syndrome to predict the pollinators of plants on Yongxing Island. We used the species-level specialization of pollination networks to compare the difference of plant ecological specialization among floral traits. The result of full model was not significant, indicating that floral traits did not affect the pollinator functional groups. The five floral traits explained only 22.5% of the pollinator's visitation preference. Our results showed that plants were visited by more pollinator species than pollination syndromes predicted. Plants with restrictive flowers showed higher specialization than those with unrestrictive flowers, while other floral traits exhibited no significant effect on plant specialization. Generalized pollination system on oceanic island might influence the predictive accuracy of pollination syndromes and the relationship between floral traits and plant ecological specialization. Our findings highlighted the utility and limitations of pollination syndromes concept in oceanic island communities.
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Affiliation(s)
- Xiangping Wang
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, Guangdong, China
| | - Meihong Wen
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, Guangdong, China
| | - Xin Qian
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, Guangdong, China
| | - Nancai Pei
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Dianxiang Zhang
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, Guangdong, China.
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9
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Fuster F, Kaiser-Bunbury CN, Traveset A. Pollination effectiveness of specialist and opportunistic nectar feeders influenced by invasive alien ants in the Seychelles. AMERICAN JOURNAL OF BOTANY 2020; 107:957-969. [PMID: 32592166 DOI: 10.1002/ajb2.1499] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 03/27/2020] [Indexed: 06/11/2023]
Abstract
PREMISE Opportunistic nectar-feeders may act as effective pollinators; nonetheless, we still lack information on whether these opportunistic species differ in their pollination effectiveness from specialized nectarivorous vertebrates and insects. Many nectar specialists have coevolved with the plants on which they feed; therefore, we would expect higher pollination effectiveness in specialists than in opportunistic feeders. Here, we assessed quantity and quality components of pollination effectiveness in specialist and opportunistic vertebrate nectarivores and insects, focusing on three plants from the Seychelles: Thespesia populnea, Polyscias crassa, and Syzygium wrightii. METHODS We determined the quantity component (QNC) of pollination effectiveness with pollinator observations, and the quality component (QLC) by measuring fruit and seed set resulting from single visits by each pollinator. To detect potential negative effects of invasive ants on native plant-pollinator interactions, we classified pollinator visits (quantity component) as disturbed (>6 ants/30 min) vs. undisturbed. RESULTS All focal plants were visited by insects, and vertebrate specialist and opportunist nectarivores, yet their pollination effectiveness differed. Flying insects were the most effective pollinators of T. populnea. The other two plants were most effectively pollinated by vertebrates; i.e., sunbirds (nectar specialists) in S. wrightii and Phelsuma geckos (nectar opportunists) in P. crassa, despite marked variation in QNC and QLC. Ant presence was associated with lower pollinator visitation rate in P. crassa and S. wrightii. CONCLUSIONS Our study highlights the importance of all pollinator guilds, including opportunist nectarivorous vertebrates as pollinators of island plants, and the vulnerability of such interactions to disruption by nonnative species.
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Affiliation(s)
- Francisco Fuster
- Global Change Research Group, Institut Mediterrani d'Estudis Avançats (CSIC-UIB), Miquel Marqués 21, 07190, Esporles, Mallorca, Balearic Islands, Spain
| | - Christopher N Kaiser-Bunbury
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Cornwall Campus, Penryn, TR10 9FE, UK
| | - Anna Traveset
- Global Change Research Group, Institut Mediterrani d'Estudis Avançats (CSIC-UIB), Miquel Marqués 21, 07190, Esporles, Mallorca, Balearic Islands, Spain
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10
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Diller C, Castañeda-Zárate M, Johnson SD. Generalist birds outperform specialist sunbirds as pollinators of an African Aloe. Biol Lett 2019; 15:20190349. [PMID: 31362606 DOI: 10.1098/rsbl.2019.0349] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Bird pollination systems are dominated by specialist nectarivores, such as hummingbirds in the Americas and sunbirds in Africa. Opportunistic (generalist) avian nectarivores such as orioles, weavers and bulbuls have also been implicated as plant pollinators, but their effectiveness as agents of pollen transfer is poorly known. Here, we compare the single-visit effectiveness of specialist and opportunistic avian nectarivores as pollinators of Aloe ferox, a plant that relies almost exclusively on birds for seed production. We found that the number of pollen grains on stigmas of flowers receiving single visits by opportunistic avian nectarivores was approximately threefold greater than on those receiving single visits by specialist sunbirds and about twofold greater than on those that received single visits by honeybees. The number of pollen grains on stigmas of flowers visited by sunbirds was similar to that on stigmas of unvisited flowers. These results show that opportunistic birds are highly effective pollinators of A. ferox, supporting the idea that some plants are specialized for pollination by opportunistic birds.
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Affiliation(s)
- Carolina Diller
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermartizburg 3209, South Africa
| | - Miguel Castañeda-Zárate
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermartizburg 3209, South Africa
| | - Steven D Johnson
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermartizburg 3209, South Africa
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11
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Abrahamczyk S. Comparison of the ecology and evolution of plants with a generalist bird pollination system between continents and islands worldwide. Biol Rev Camb Philos Soc 2019; 94:1658-1671. [DOI: 10.1111/brv.12520] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 04/15/2019] [Accepted: 04/18/2019] [Indexed: 01/06/2023]
Affiliation(s)
- Stefan Abrahamczyk
- Nees‐Institute for Biodiversity of PlantsUniversity of Bonn 53115 Bonn Germany
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12
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Hervías-Parejo S, Heleno R, Nogales M, Olesen JM, Traveset A. Divergence in floral trait preferences between nonflower-specialized birds and insects on the Galápagos. AMERICAN JOURNAL OF BOTANY 2019; 106:540-546. [PMID: 30985925 DOI: 10.1002/ajb2.1270] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 01/29/2019] [Indexed: 06/09/2023]
Abstract
PREMISE OF THE STUDY The characteristic scarcity of insects on remote oceanic islands has driven nonflower-specialized vertebrates to broaden their trophic niches and explore floral resources. From our previous studies in the Galápagos, we know that native insectivorous and frugivorous birds visit a wide range of entomophilous flowers and can also act as effective pollinators. Here, we tested whether opportunistic Galápagos birds show any preference for specific floral traits, and if so, this preference differs from that of insects. METHODS Sixteen floral morphology and nectar traits of 26 native species were studied, as well as the frequency with which they are visited by birds and insects. Nonmetric multidimensional scaling (NMDS) was used to evaluate the distribution of flower traits values along two main dimensions and measure the similarity between the plants visited mostly by birds versus those by insects. KEY RESULTS NMDS of floral traits resulted in two species groups: (1) bell-shaped, white flowers with wider corollas at nectary level and higher nectar volume, associated with high bird visitation rates; and (2) bowl and tubular-shaped flowers with narrower corollas at nectary level and lower nectar volume, associated with high insect visitation rates. CONCLUSIONS Despite the divergence in floral trait preferences between opportunistic Galápagos birds and insects, bird-visited flowers display mixed traits not fitting the classical ornithophilous syndrome. This finding is compatible with the existence of a transitional or bet-hedging phenotype between insect and bird visitors and underscores the importance of coevolution and floral diversification in nonspecialized plant-visitor interactions.
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Affiliation(s)
- Sandra Hervías-Parejo
- Institut Mediterrani d'Estudis Avançats (CSIC-UIB), Global Change Research Group, Mallorca, Balearic Islands, Spain
| | - Ruben Heleno
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Portugal
| | - Manuel Nogales
- Instituto de Productos Naturales y Agrobiología (CSIC-IPNA), Island Ecology and Evolution Research Group, Canary Islands, Spain
| | - Jens M Olesen
- Department of Bioscience, Aarhus University, Denmark
| | - Anna Traveset
- Institut Mediterrani d'Estudis Avançats (CSIC-UIB), Global Change Research Group, Mallorca, Balearic Islands, Spain
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13
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Swift S, Munroe S, Im C, Tipton L, Hynson NA. Remote tropical island colonization does not preclude symbiotic specialists: new evidence of mycorrhizal specificity across the geographic distribution of the Hawaiian endemic orchid Anoectochilus sandvicensis. ANNALS OF BOTANY 2019; 123:657-666. [PMID: 30380004 PMCID: PMC6417469 DOI: 10.1093/aob/mcy198] [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: 05/16/2018] [Accepted: 10/04/2018] [Indexed: 05/20/2023]
Abstract
BACKGROUND AND AIMS For symbiotic organisms, their colonization and spread across remote oceanic islands should favour generalists. Plants that form obligate symbiotic associations with microbes dominate island ecosystems, but the relationship between island inhabitance and symbiotic specificity is unclear, especially in the tropics. To fill this gap, we examined the mycorrhizal specificity of the Hawaiian endemic orchid Anoectochilus sandvicensis across multiple populations encompassing its entire geographic distribution. METHODS By molecular phylogenetic approaches we identified the mycorrhizal fungi associated with A. sandvicensis across its entire geographic distribution and determined the relationship of these fungi to others found elsewhere around the globe. With richness estimators, we assessed the mycorrhizal specificity of A. sandvicensis within and among islands. We then tested whether geographic proximity of orchid populations was a significant predictor for the presence of particular mycorrhizal fungi and their community composition. KEY RESULTS We found that each population of A. sandvicensis forms specific associations with one of three fungi in the genus Ceratobasidium and that the closest relatives of these fungi are globally widespread. Based on diversity indices, A. sandvicensis populations were estimated to partner with one to four mycorrhizal taxa with an estimated total of four compatible mycorrhizal fungi across its entire distribution. However, the geographic proximity of orchid populations was not a significant predictor of mycorrhizal fungal community composition. CONCLUSIONS Our findings indicate that the colonization and survival of plant species on even the most remote oceanic islands is not restricted to symbiotic generalists, and that partnering with few, but cosmopolitan microbial symbionts is an alternative means for successful island establishment. We suggest that the spatial distribution and abundance of symbionts in addition to island age, size and isolation should also be taken into consideration for predictions of island biodiversity.
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Affiliation(s)
- Sean Swift
- Department of Botany, University of Hawaii Manoa, Honolulu, HI, USA
| | - Sherilyn Munroe
- Department of Botany, University of Hawaii Manoa, Honolulu, HI, USA
| | - Chaewon Im
- John A. Burns School of Medicine, University of Hawaii Manoa, Honolulu, HI, USA
| | - Laura Tipton
- Department of Botany, University of Hawaii Manoa, Honolulu, HI, USA
| | - Nicole A Hynson
- Pacific Biosciences Research Center, University of Hawaii Manoa, Honolulu, HI, USA
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Fuster F, Traveset A. Evidence for a double mutualistic interaction between a lizard and a Mediterranean gymnosperm, Ephedra fragilis. AOB PLANTS 2019; 11:plz001. [PMID: 30800260 PMCID: PMC6379517 DOI: 10.1093/aobpla/plz001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 01/09/2019] [Indexed: 05/24/2023]
Abstract
An increasing number of double mutualisms (i.e. two interacting species benefiting each other in two different functions, e.g. pollination and seed dispersal) have been reported, mainly from island ecosystems, although we still lack much information on how effective such species are in both processes. Here, we assessed the pollination effectiveness of a double mutualism between an ancient Mediterranean gymnosperm, Ephedra fragilis, and a lizard, Podarcis lilfordi. On the one hand, we assessed the lizard contribution to different fitness measures (seed set and germination success), relative to that of insects and the wind effect; on the other, we determined the lizards' seed removal rate (i.e. the quantity component of seed dispersal effectiveness). In both processes, we further tested for differences in their contributions among male, female and juvenile lizards. Ephedra fragilis showed to be mostly anemophilous, lizards and insects playing only a minor role on seed set. However, lizards qualitatively contributed to pollination success, as seeds coming from lizard-pollinated cones germinated at higher rates than those pollinated by wind or insects, although this was detected only for small seeds (<8 mg). The plant produced a low seed set (c. 23 %), which was compensated by a high seed germinability (c. 70 %). Adult male lizards were those most implicated in pollination, quantitatively more important than insects, and in seed dispersal. This work, thus, reports the importance of a lizard species in one of the few double mutualisms found in the World involving a gymnosperm, and it represents the first documentation of a double mutualism in the Mediterranean region. Our findings further contribute to highlight the role of both inter- and intraspecific differences in the effectiveness of mutualistic interactions.
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Affiliation(s)
- Francisco Fuster
- Global Change Research Group, Institut Mediterrani d’Estudis Avançats (CSIC-UIB), Mallorca, Balearic Islands, Spain
| | - Anna Traveset
- Global Change Research Group, Institut Mediterrani d’Estudis Avançats (CSIC-UIB), Mallorca, Balearic Islands, Spain
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