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Palacio FX, Ordano M. Urbanization shapes phenotypic selection of fruit traits in a seed-dispersal mutualism. Evolution 2023; 77:1769-1779. [PMID: 37128948 DOI: 10.1093/evolut/qpad081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 04/21/2023] [Accepted: 04/28/2023] [Indexed: 05/03/2023]
Abstract
Urbanization is currently one of the trademarks of the Anthropocene, accelerating evolutionary processes and reshaping ecological interactions over short time scales. Species interactions represent a fundamental pillar of diversity that is being altered globally by anthropogenic change. Urban environments, despite their potential impact, have seldom been studied in relation to how they shape natural selection of phenotypic traits in multispecies interactions. Using a seed-dispersal mutualism as a study system, we estimated the regime and magnitude of phenotypic selection exerted by frugivores on fruit and seed traits across three plant populations with different degrees of urbanization (urban, semiurban, and rural). Urbanization weakened phenotypic selection via an indirect positive impact on fruit production and fitness and, to a lesser extent, through a direct positive effect on species visitation rates. Our results show that urban ecosystems may affect multifarious selection of traits in the short term and highlight the role of humans in shaping eco-evolutionary dynamics of multispecies interactions.
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Affiliation(s)
- Facundo X Palacio
- Sección Ornitología, División Zoología Vertebrados, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata and Consejo Nacional de Investigaciones Científicas y Técnicas, La Plata, Argentina
| | - Mariano Ordano
- Fundación Miguel Lillo, San Miguel de Tucumán, Argentina
- Instituto de Ecología Regional, Universidad Nacional de Tucumán, Consejo Nacional de Investigaciones Científicas y Técnicas, Yerba Buena, Argentina
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2
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Palacio FX, Cataudela JF, Montalti D, Ordano M. On the adequacy of fruit removal as a proxy for fitness in studies of bird-mediated phenotypic selection. AMERICAN JOURNAL OF BOTANY 2023; 110:1-12. [PMID: 36706269 DOI: 10.1002/ajb2.16130] [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: 04/22/2022] [Revised: 12/26/2022] [Accepted: 12/29/2022] [Indexed: 05/11/2023]
Abstract
PREMISE In fleshy-fruited plants, fruit removal is widely used as a proxy for plant reproductive success. Nevertheless, this proxy may not accurately reflect the number of seeds dispersed, an assumed better proxy for total fitness (fruit removal × mean number of seeds dispersed per fruit). METHODS We examined under what circumstances fruit removal can be reliable as a proxy for total fitness when assessing bird-mediated selection on fruit traits. In three populations of the Blue Passionflower (Passiflora caerulea), we used the number of fruits pecked per plant as a surrogate for fruit removal to estimate phenotypic selection on fruit and seed traits, and simulations of the effect of the fruit-seed number trade-off on the number of fruits removed. RESULTS Fruit removal was a good indicator of fitness, accounting for 55 to 68% of the variability in total fitness, measured as total number of seeds removed. Moreover, multivariate selection analyses on fruit crop size, mean fruit diameter and mean seed number using fruit removal as a fitness proxy yielded similar selection regimes to those using total fitness. Simulations showed that producing more fruits, a lower number of seeds per fruit, and a higher variability in seed number can result in a negative relationship between fruit removal and total fitness. CONCLUSIONS Our results suggest that fruit removal can be reliably used as a proxy for total fitness when (1) there is a weak fruit number-seed number trade-off, (2) fruit crop size and fruit removal correlate positively, and (3) seed number variability does not largely exceed fruit number variability.
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Affiliation(s)
- Facundo X Palacio
- Sección Ornitología, División Zoología Vertebrados, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata and Consejo Nacional de Investigaciones Científicas y Técnicas, La Plata, Argentina
| | - Juan Francisco Cataudela
- Laboratorio de Biología de la Conservación, Centro de Ecología Aplicada del Litoral, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional del Nordeste, Corrientes, Argentina
| | - Diego Montalti
- Sección Ornitología, División Zoología Vertebrados, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata and Consejo Nacional de Investigaciones Científicas y Técnicas, La Plata, Argentina
| | - Mariano Ordano
- Fundación Miguel Lillo, San Miguel de Tucumán, Argentina
- Instituto de Ecología Regional, Universidad Nacional de Tucumán, Consejo Nacional de Investigaciones Científicas y Técnicas, Yerba Buena, Argentina
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3
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Significance of seed dispersal by the largest frugivore for large-diaspore trees. Sci Rep 2022; 12:19086. [PMID: 36411297 PMCID: PMC9678871 DOI: 10.1038/s41598-022-23018-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 10/21/2022] [Indexed: 11/23/2022] Open
Abstract
How do large-bodied frugivores contribute to seed dispersal of large-diaspore plants? This study examined seed dispersal effectiveness for two large-diaspore tree species, Astrotrichilia asterotricha (AA) and Abrahamia deflexa (AD), in a Madagascan forest. I evaluated fruit removal rates through focal tree observations and factors affecting seedling recruitment up to the 2-year-old seedling stage. I confirmed brown lemur (Eulemur fulvus) as the sole disperser, removing 58.8% and 26.0% of fruits produced by AA and AD. Brown lemurs frequently visited large-crowned AA trees with high density of fallen fruits and more adjacent fruiting trees during seasons with low fruit diversity. Most AA seedlings were removed by predators, although canopy openness slightly improved seedling establishment. Although AD seeds were severely attacked by predators under mother trees, the seedlings survived under dispersal conditions distant from the mother trees, and with low density of diaspores. AD had a higher cumulative probability from fruit removal to seedling recruitment (6.5%) than AA (1.5%) in the first rainy season. This study clarifies the significance of seed dispersal to tree recruitment strategies, which vary among different combinations of tree species and large frugivores, i.e. quantitative dispersal to reach suitable microhabitats, and qualitative dispersal to escape from dangerous zones near mother trees.
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Using a Phylogenetic Framework to Assess the Role of Fruit Size in Food Selection by the Andean Night Monkey (Aotus lemurinus). INT J PRIMATOL 2022. [DOI: 10.1007/s10764-021-00274-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Gómez JM, Schupp EW, Jordano P. The ecological and evolutionary significance of effectiveness landscapes in mutualistic interactions. Ecol Lett 2021; 25:264-277. [PMID: 34971487 DOI: 10.1111/ele.13939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/08/2021] [Accepted: 11/17/2021] [Indexed: 11/30/2022]
Abstract
Mutualism effectiveness, the contribution of an interacting organism to its partner's fitness, is defined as the number of immediate outcomes of the interactions (quantity component) multiplied by the probability that an immediate outcome results in a new individual (quality component). These components form a two-dimensional effectiveness landscape with each species' location determined by its values of quantity (x-axis) and quality (y-axis). We propose that the evolutionary history of mutualistic interactions leaves a footprint that can be identified by three properties of the spatial structure of effectiveness values: dispersion of effectiveness values, relative contribution of each component to the effectiveness values and correlation between effectiveness components. We illustrate this approach using a large dataset on synzoochory, seed dispersal by seed-caching animals. The synzoochory landscape was clumped, with effectiveness determined primarily by the quality component, and with quantity and quality positively correlated. We suggest this type of landscape structure is common in generalised coevolved mutualisms, where multiple functionally equivalent, high-quality partners exert similarly strong selection. Presumably, only those organisms located in high-quality regions will impact the evolution of their partner. Exploring properties of effectiveness landscapes in other mutualisms will provide new insight into the evolutionary and ecological consequences of mutualisms.
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Affiliation(s)
- José María Gómez
- Departamento de Ecología Funcional y Evolutiva, Estación Experimental de Zonas Áridas (EEZA- CSIC), Almería, Spain
| | - Eugene W Schupp
- Department of Wildland Resources and Ecology Center, S. J. and Jesse E. Quinney College of Natural Resources, Utah State University, Logan, Utah, USA.,Integrative Ecology Group, Estación Biológica de Doñana (EBD-CSIC), Sevilla, Spain
| | - Pedro Jordano
- Integrative Ecology Group, Estación Biológica de Doñana (EBD-CSIC), Sevilla, Spain.,Departamento de Biología Vegetal y Ecología, Universidad de Sevilla, Sevilla, Spain
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Fruit Size and Structure of Zoochorous Trees: Identifying Drivers for the Foraging Preferences of Fruit-Eating Birds in a Mexican Successional Dry Forest. Animals (Basel) 2021; 11:ani11123343. [PMID: 34944120 PMCID: PMC8697955 DOI: 10.3390/ani11123343] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 11/10/2021] [Accepted: 11/15/2021] [Indexed: 11/16/2022] Open
Abstract
Simple Summary Tropical dry forests are highly threatened by human activities such as agriculture, livestock, and selective logging. These activities have resulted in fragments of tropical dry forest under different successional stages that negatively affect the interaction between plants and fruit-eating birds. We analyzed the consumption of the fruits of zoochorous trees by birds during the dry season in a tropical dry forest and evaluated whether the horizontal and vertical structure of these trees explains fruit consumption. We also related the bird body mass and fruit size removed from zoochorous trees. We found that the tree structure can influence the visitation of fruit-eating birds, and therefore, the number of fruits consumed as the succession progresses. There was a relationship between fruit sizes and bird body mass in the successional gradient. Our results indicate that structural and fruit traits of zoochorous trees drive foraging preferences of fruit-eating birds, whose interactions in different successional stages can help to reverse the negative effects of fragmentation in tropical dry forests of the study area. Abstract Tropical dry forests (TDFs) are affected by land-use changes. These modifications impact their composition and arboreal structure, as well as the availability of food for several bird groups. In this study, we evaluated the foraging preferences in zoochorous trees of fruit-eating birds during the dry season of the year in three successional stages (early, intermediate, and mature) of TDFs in southern Mexico. The fruits of these trees are important in the diet of several birds during the dry season, a period during which food resources are significantly reduced in TDFs. We estimated foliar cover (FC) and foliage height diversity (FHD) of zoochorous trees in 123 circular plots. These variables were recognized as proxies of food availability and tree productivity. Foraging preferences were evaluated at the community level, by frugivore type, and by bird species. We evaluated the effect of the structural variables and the fruit size of zoochorous plants on fruit removal by birds and related the bird body mass and fruit size removed in the successional gradient. A total of 14 zoochorous tree species and 23 fruit-eating bird species were recorded along the successional gradient. Intermediate and mature stages showed greater fruit removal. The birds removed mainly B. longipes fruits across the three successional stages. The FHD and fruit size were important drivers in the selection of zoochorous trees and fruit removal by fruit-eating birds. Fruit size and bird body mass were positively related along the successional gradient. The results suggest that fruit removal by fruit-eating birds in the successional gradient can promote the demographic dynamics of several zoochorous tree species, especially of Bursera spp. along the TDFs.
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Schubert SC, Walters EL. Subannual phenology and the effect of staggered fruit ripening on dispersal competition. Biotropica 2021. [DOI: 10.1111/btp.13024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Spencer C. Schubert
- Department of Biological Sciences Old Dominion University Norfolk Virginia USA
| | - Eric L. Walters
- Department of Biological Sciences Old Dominion University Norfolk Virginia USA
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Tonos J, Razafindratsima OH, Fenosoa ZSE, Dunham AE. Individual‐based networks reveal the highly skewed interactions of a frugivore mutualist with individual plants in a diverse community. OIKOS 2021. [DOI: 10.1111/oik.08539] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jadelys Tonos
- Rice Univ., Biosciences Dept Houston TX USA
- Centre ValBio, Ranomafana National Park Ifanadiana Madagascar
| | - Onja H. Razafindratsima
- Centre ValBio, Ranomafana National Park Ifanadiana Madagascar
- Dept of Integrative Biology, Univ. of California Berkeley CA USA
| | - Zo Samuel Ella Fenosoa
- Centre ValBio, Ranomafana National Park Ifanadiana Madagascar
- Ecole Doctorale Sciences de la Vie et de l'Environnement, Univ. d'Antananarivo Antananarivo Madagascar
| | - Amy E. Dunham
- Rice Univ., Biosciences Dept Houston TX USA
- Centre ValBio, Ranomafana National Park Ifanadiana Madagascar
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Camargo PHSA, Carlo TA, Brancalion PHS, Pizo MA. Frugivore diversity increases evenness in the seed rain on deforested tropical landscapes. OIKOS 2021. [DOI: 10.1111/oik.08028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Paulo H. S. A. Camargo
- Univ. Estadual Paulista (Unesp), Inst. de Biociências Rio Claro SP Brasil
- Biology Dept, 208 Mueller Laboratory, The Pennsylvania State Univ. State College Pennsylvania USA
| | - Tomás A. Carlo
- Biology Dept, 208 Mueller Laboratory, The Pennsylvania State Univ. State College Pennsylvania USA
| | - Pedro H. S. Brancalion
- Dept of Forest Sciences, ‘Luiz de Queiroz' College of Agriculture, Univ. of São Paulo Piracicaba SP Brazil
| | - Marco A. Pizo
- Univ. Estadual Paulista (Unesp), Inst. de Biociências Rio Claro SP Brasil
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Palacio FX, Cataudela JF, Montalti D, Ordano M. Do frugivores exert selection on fruiting phenology? Potential scenarios across three plant populations of a Neotropical vine, Passiflora caerulea. Evol Ecol 2021. [DOI: 10.1007/s10682-021-10121-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Rojas TN, Bruzzone OA, Zampini IC, Isla MI, Blendinger PG. A combination of rules govern fruit trait preference by frugivorous bat and bird species: nutrients, defence and size. Anim Behav 2021. [DOI: 10.1016/j.anbehav.2021.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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12
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Plant origin and fruit traits shape fruit removal patterns by native birds in invaded plant communities. Biol Invasions 2020. [DOI: 10.1007/s10530-020-02407-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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13
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Seed Removal Rates in Forest Remnants Respond to Forest Loss at the Landscape Scale. FORESTS 2020. [DOI: 10.3390/f11111144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Seed removal is a key component of seed dispersal and may be influenced by both landscape-scale and local attributes, and it has been used as an indicator of the intensity of interactions between ecosystem components. We examined how the seed removal rates, which integrate the activity of seed dispersers and seed predators, vary with landscape-scale forest cover. We collected data under 34 trees belonging to two zoochoric species (Helicostylis tomentosa (Poepp. and Endl.) J. F. Macbr. and Inga vera Willd.) in 17 remnants in the Brazilian Atlantic forest, with different percentages of forest cover. The seed removal rate was estimated using a fast method based on the abundance of intact fruits and fruit scraps on the ground. The amount of forest cover affected the rate of seed removal in a humpbacked shape, with a maximum seed removal rate at intermediate forest cover. Seed removal rates must be related to the amount of food resources offered and diversity of dispersers and predators in the region. In landscapes with intermediate forest amount, there is a better balance between supply and demand for fruits, leading to a higher seed removal rate than more deforested or forested landscape. Our results also show that local factors, such as crop size and canopy surface, together with forest cover amount, are also important to the removal rate, depending on the species. In addition, our results showed that plant–animal interactions are occurring in all fragments, but the health status of these forests is similar to disturbed forests, even in sites immersed in forested landscapes.
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Selwyn M, Garrote PJ, Castilla AR, Fedriani JM. Interspecific interactions among functionally diverse frugivores and their outcomes for plant reproduction: A new approach based on camera-trap data and tailored null models. PLoS One 2020; 15:e0240614. [PMID: 33064761 PMCID: PMC7567357 DOI: 10.1371/journal.pone.0240614] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 09/29/2020] [Indexed: 11/18/2022] Open
Abstract
The study of plant-frugivore interactions is essential to understand the ecology and evolution of many plant communities. However, very little is known about how interactions among frugivores indirectly affect plant reproductive success. In this study, we examined direct interactions among vertebrate frugivores sharing the same fruit resources. Then, we inferred how the revealed direct interspecific interactions could lead to indirect (positive or negative) effects on reproductive success of fleshy fruited plants. To do so, we developed a new analytical approach that combines camera trap data (spatial location, visitor species, date and time, activity) and tailored null models that allowed us to infer spatial-temporal interactions (attraction, avoidance or indifference) between pairs of frugivore species. To illustrate our approach, we chose to study the system composed by the Mediterranean dwarf palm, Chamaerops humilis, the Iberian pear tree, Pyrus bourgaeana, and their shared functionally diverse assemblages of vertebrate frugivores in a Mediterranean area of SW Spain. We first assessed the extent to which different pairs of frugivore species tend to visit the same or different fruiting individual plants. Then, for pairs of species that used the same individual plants, we evaluated their spatial-temporal relationship. Our first step showed, for instance, that some prey frugivore species (e.g. lagomorphs) tend to avoid those C. humilis individuals that were most visited by their predators (e.g. red foxes). Also, the second step revealed temporal attraction between large wild and domestic frugivore ungulates (e.g. red deer, cows) and medium-sized frugivores (e.g. red foxes) suggesting that large mammals could facilitate the C. humilis and P. bourgaeana exploitation to other smaller frugivores by making fruits more easily accessible. Finally, our results allowed us to identify direct interaction pathways, that revealed how the mutualistic and antagonistic relations between animal associates derived into indirect effects on both plants seed dispersal success. For instance, we found that large-sized seed predators (e.g. ungulates) had a direct positive effect on the likelihood of visits by legitimate seed dispersers (e.g. red foxes) to both fleshy fruited plants. Then, seed predators showed an indirect positive effect on the plants' reproductive success. Our new analytical approach provides a widely applicable framework for further studies on multispecies interactions in different systems beyond plant-frugivore interactions, including plant-pollinator interactions, the exploitation of plants by herbivores, and the use of carcasses by vertebrate scavengers.
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Affiliation(s)
- Miriam Selwyn
- Centro de Ecologia Aplicada “Prof. Baeta Neves” CEABN/InBIO, Instituto Superior de Agronomia, Universidade de Lisboa, Lisboa, Portugal
| | - Pedro J. Garrote
- Centro de Ecologia Aplicada “Prof. Baeta Neves” CEABN/InBIO, Instituto Superior de Agronomia, Universidade de Lisboa, Lisboa, Portugal
| | - Antonio R. Castilla
- Centro de Ecologia Aplicada “Prof. Baeta Neves” CEABN/InBIO, Instituto Superior de Agronomia, Universidade de Lisboa, Lisboa, Portugal
| | - Jose M. Fedriani
- Centro de Investigaciones sobre Desertificación (CIDE-CSIC) Carretera Moncada - Náquera, Moncada, Valencia, Spain
- Estación Biológica de Doñana (EBD - C.S.I.C.), Seville, Spain
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Palacio FX, Siepielski AM, Lacoretz MV, Ordano M. Selection on fruit traits is mediated by the interplay between frugivorous birds, fruit flies, parasitoid wasps and seed‐dispersing ants. J Evol Biol 2020; 33:874-886. [DOI: 10.1111/jeb.13656] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 05/08/2020] [Accepted: 05/26/2020] [Indexed: 12/01/2022]
Affiliation(s)
- Facundo X. Palacio
- Fundación Miguel Lillo and Consejo Nacional de Investigaciones Científicas y Técnicas Tucumán Argentina
| | - Adam M. Siepielski
- Department of Biological Sciences University of Arkansas Fayetteville AR USA
| | - Mariela V. Lacoretz
- Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires Buenos Aires Argentina
| | - Mariano Ordano
- Fundación Miguel Lillo and Consejo Nacional de Investigaciones Científicas y Técnicas Tucumán Argentina
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16
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Schupp EW, Zwolak R, Jones LR, Snell RS, Beckman NG, Aslan C, Cavazos BR, Effiom E, Fricke EC, Montaño-Centellas F, Poulsen J, Razafindratsima OH, Sandor ME, Shea K. Intrinsic and extrinsic drivers of intraspecific variation in seed dispersal are diverse and pervasive. AOB PLANTS 2019; 11:plz067. [PMID: 31857875 PMCID: PMC6914678 DOI: 10.1093/aobpla/plz067] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 10/09/2019] [Indexed: 05/23/2023]
Abstract
There is growing realization that intraspecific variation in seed dispersal can have important ecological and evolutionary consequences. However, we do not have a good understanding of the drivers or causes of intraspecific variation in dispersal, how strong an effect these drivers have, and how widespread they are across dispersal modes. As a first step to developing a better understanding, we present a broad, but not exhaustive, review of what is known about the drivers of intraspecific variation in seed dispersal, and what remains uncertain. We start by decomposing 'drivers of intraspecific variation in seed dispersal' into intrinsic drivers (i.e. variation in traits of individual plants) and extrinsic drivers (i.e. variation in ecological context). For intrinsic traits, we further decompose intraspecific variation into variation among individuals and variation of trait values within individuals. We then review our understanding of the major intrinsic and extrinsic drivers of intraspecific variation in seed dispersal, with an emphasis on variation among individuals. Crop size is the best-supported and best-understood intrinsic driver of variation across dispersal modes; overall, more seeds are dispersed as more seeds are produced, even in cases where per seed dispersal rates decline. Fruit/seed size is the second most widely studied intrinsic driver, and is also relevant to a broad range of seed dispersal modes. Remaining intrinsic drivers are poorly understood, and range from effects that are probably widespread, such as plant height, to drivers that are most likely sporadic, such as fruit or seed colour polymorphism. Primary extrinsic drivers of variation in seed dispersal include local environmental conditions and habitat structure. Finally, we present a selection of outstanding questions as a starting point to advance our understanding of individual variation in seed dispersal.
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Affiliation(s)
- Eugene W Schupp
- Department of Wildland Resources and Ecology Center, Utah State University, Logan, UT, USA
| | - Rafal Zwolak
- Department of Systematic Zoology, Adam Mickiewicz University, Poznań, Poland
| | - Landon R Jones
- Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN, USA
| | - Rebecca S Snell
- Environmental and Plant Biology, Ohio University, Athens, OH, USA
| | - Noelle G Beckman
- Department of Biology and Ecology Center, Utah State University, Logan, UT, USA
| | - Clare Aslan
- Landscape Conservation Initiative, Northern Arizona University, Flagstaff, AZ, USA
| | - Brittany R Cavazos
- Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, IA, USA
| | - Edu Effiom
- REDD & Biodiversity Unit, Cross River State Forestry Commission, Calabar, Nigeria
| | - Evan C Fricke
- National Socio-Environmental Synthesis Center, University of Maryland, Annapolis, MD, USA
| | | | - John Poulsen
- Nicholas School of the Environment, Duke University, Durham, NC, USA
| | - Onja H Razafindratsima
- Department of Natural Resource Management, South Dakota State University, Brookings, SD, USA
| | - Manette E Sandor
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York, NY, USA
- Center for Biodiversity and Conservation, American Museum of Natural History, New York, NY, USA
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