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Chaverri G, Sagot M, Stynoski JL, Araya-Salas M, Araya-Ajoy Y, Nagy M, Knörnschild M, Chaves-Ramírez S, Rose N, Sánchez-Chavarría M, Jiménez-Torres Y, Ulloa-Sanabria D, Solís-Hernández H, Carter GG. Calling to the collective: contact calling rates within groups of disc-winged bats do not vary by kinship or association. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230195. [PMID: 38768198 DOI: 10.1098/rstb.2023.0195] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 02/23/2024] [Indexed: 05/22/2024] Open
Abstract
Many group-living animals coordinate social behaviours using contact calls, which can be produced for all group members or targeted at specific individuals. In the disc-winged bat, Thyroptera tricolor, group members use 'inquiry' and 'response' calls to coordinate daily movements into new roosts (furled leaves). Rates of both calls show consistent among-individual variation, but causes of within-individual variation remain unknown. Here, we tested whether disc-winged bats produce more contact calls towards group members with higher kinship or association. In 446 experimental trials, we recorded 139 random within-group pairs of one flying bat (producing inquiry calls for roost searching) and one roosting bat (producing response calls for roost advertising). Using generalized linear mixed-effect models (GLMM), we assessed how response and inquiry calling rates varied by sender, receiver, genetic kinship and co-roosting association rate. Calling rates varied consistently across senders but not by receiver. Response calling was influenced by inquiry calling rates, but neither calling rate was higher when the interacting pair had higher kinship or association. Rather than dyadic calling rates indicating within-group relationships, our findings are consistent with the hypothesis that bats produce contact calls to maintain contact with any or all individuals within a group while collectively searching for a new roost site. This article is part of the theme issue 'The power of sound: unravelling how acoustic communication shapes group dynamics'.
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Affiliation(s)
- Gloriana Chaverri
- Sede del Sur, Universidad de Costa Rica , 60701, Costa Rica
- Smithsonian Tropical Research Institute , 0843-03092, Panama
| | - Maria Sagot
- Department of Biological Sciences, State University of New York at Oswego , Oswego, NY 13126, USA
| | - Jennifer L Stynoski
- Instituto Clodomiro Picado, Universidad de Costa Rica , Coronado, San José 11103, Costa Rica
| | - Marcelo Araya-Salas
- Centro de Investigación en Neurociencias, Universidad de Costa Rica , San Pedro, San José 11501-2060, Costa Rica
- Escuela de Biología, Universidad de Costa Rica , , San José 11501-2060, Costa Rica
| | - Yimen Araya-Ajoy
- Department of Biology, Centre for Biodiversity Dynamics (CBD), Norwegian University of Science and Technology (NTNU) , , N-7491, Norway
| | - Martina Nagy
- Museum für Naturkunde, Leibniz-Institute for Evolution and Biodiversity Science , Berlin 10115, Germany
| | - Mirjam Knörnschild
- Museum für Naturkunde, Leibniz-Institute for Evolution and Biodiversity Science , Berlin 10115, Germany
| | - Silvia Chaves-Ramírez
- Programa de Posgrado en Biología, Universidad de Costa Rica , , San José 11501-2060, Costa Rica
| | - Nicole Rose
- Department of Biological Sciences, State University of New York at Oswego , Oswego, NY 13126, USA
| | - Mariela Sánchez-Chavarría
- Programa de Posgrado en Gestión Integrada de Áreas Costeras Tropicales, Universidad de Costa Rica , , San José 11501-2060, Costa Rica
| | | | | | | | - Gerald G Carter
- Smithsonian Tropical Research Institute , 0843-03092, Panama
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University , Columbus, OH 43210, USA
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Hernández-Pinsón HA, Chaves-Ramírez S, Chaverri G. Seasonality in the Emission of Contact Calls in Spix's Disc-Winged Bats (Thyroptera tricolor) Suggests a Potential Role in Mate Attraction. ACTA CHIROPTEROLOGICA 2022. [DOI: 10.3161/15081109acc2021.23.2.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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3
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Bachorec E, Horáček I, Hulva P, Konečný A, Lučan RK, Jedlička P, Shohdi WM, Řeřucha Š, Abi‐Said M, Bartonička T. Egyptian fruit bats do not preferentially roost with their relatives. J Zool (1987) 2020. [DOI: 10.1111/jzo.12816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- E. Bachorec
- Department of Botany and Zoology Masaryk University Brno Czech Republic
| | - I. Horáček
- Department of Zoology Charles University in Prague Prague Czech Republic
| | - P. Hulva
- Department of Zoology Charles University in Prague Prague Czech Republic
| | - A. Konečný
- Department of Botany and Zoology Masaryk University Brno Czech Republic
| | - R. K. Lučan
- Department of Zoology Charles University in Prague Prague Czech Republic
| | - P. Jedlička
- Institute of Scientific Instruments of the Czech Academy of Sciences (ISI) Brno Czech Republic
| | | | - Š. Řeřucha
- Institute of Scientific Instruments of the Czech Academy of Sciences (ISI) Brno Czech Republic
| | - M. Abi‐Said
- Department of Earth and Life Sciences Faculty of Sciences II Lebanese University JdeidehFanar Lebanon
| | - T. Bartonička
- Department of Botany and Zoology Masaryk University Brno Czech Republic
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Araya-Salas M, Hernández-Pinsón HA, Rojas N, Chaverri G. Ontogeny of an interactive call-and-response system in Spix's disc-winged bats. Anim Behav 2020. [DOI: 10.1016/j.anbehav.2020.05.018] [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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5
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Stervander M, Dierickx EG, Thorley J, Brooke MDL, Westerdahl H. High MHC gene copy number maintains diversity despite homozygosity in a Critically Endangered single-island endemic bird, but no evidence of MHC-based mate choice. Mol Ecol 2020; 29:3578-3592. [PMID: 32416000 DOI: 10.1111/mec.15471] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 04/14/2020] [Accepted: 05/04/2020] [Indexed: 12/30/2022]
Abstract
Small population sizes can, over time, put species at risk due to the loss of genetic variation and the deleterious effects of inbreeding. Losing diversity in the major histocompatibility complex (MHC) could be particularly harmful, given its key role in the immune system. Here, we assess MHC class I (MHC-I) diversity and its effects on mate choice and survival in the Critically Endangered Raso lark Alauda razae, a species restricted to the 7 km2 islet of Raso, Cape Verde, since ~1460, whose population size has dropped as low as 20 pairs. Exhaustively genotyping 122 individuals, we find no effect of MHC-I genotype/diversity on mate choice or survival. However, we demonstrate that MHC-I diversity has been maintained through extreme bottlenecks by retention of a high number of gene copies (at least 14), aided by cosegregation of multiple haplotypes comprising 2-8 linked MHC-I loci. Within-locus homozygosity is high, contributing to low population-wide diversity. Conversely, each individual had comparably many alleles, 6-16 (average 11), and the large and divergent haplotypes occur at high frequency in the population, resulting in high within-individual MHC-I diversity. This functional immune gene diversity will be of critical importance for this highly threatened species' adaptive potential.
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Affiliation(s)
- Martin Stervander
- Department of Biology, Lund University, Lund, Sweden.,Department of Biology and Environmental Science, Faculty of Health and Life Sciences, Linnaeus University, Kalmar, Sweden.,Institute of Ecology and Evolution, University of Oregon, Eugene, OR, USA
| | - Elisa G Dierickx
- Department of Zoology, University of Cambridge, Cambridge, UK.,Fauna & Flora International, Cambridge, UK
| | - Jack Thorley
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - M de L Brooke
- Department of Zoology, University of Cambridge, Cambridge, UK
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6
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Contact calling in context: intra- and intergroup variation in vocalization rates depend on a call’s function. Behav Ecol Sociobiol 2020. [DOI: 10.1007/s00265-020-02837-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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7
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Flores V, Carter GG, Halczok TK, Kerth G, Page RA. Social structure and relatedness in the fringe-lipped bat ( Trachops cirrhosus). ROYAL SOCIETY OPEN SCIENCE 2020; 7:192256. [PMID: 32431896 PMCID: PMC7211832 DOI: 10.1098/rsos.192256] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 03/04/2020] [Indexed: 06/11/2023]
Abstract
General insights into the causes and effects of social structure can be gained from comparative analyses across socially and ecologically diverse taxa, such as bats, but long-term data are lacking for most species. In the neotropical fringe-lipped bat, Trachops cirrhosus, social transmission of foraging behaviour is clearly demonstrated in captivity, yet its social structure in the wild remains unclear. Here, we used microsatellite-based estimates of relatedness and records of 157 individually marked adults from 106 roost captures over 6 years, to infer whether male and female T. cirrhosus have preferred co-roosting associations and whether such associations were influenced by relatedness. Using a null model that controlled for year and roosting location, we found that both male and female T. cirrhosus have preferred roosting partners, but that only females demonstrate kin-biased association. Most roosting groups (67%) contained multiple females with one or two reproductive males. Relatedness patterns and recapture records corroborate genetic evidence for female philopatry and male dispersal. Our study adds to growing evidence that many bats demonstrate preferred roosting associations, which has the potential to influence social information transfer.
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Affiliation(s)
- Victoria Flores
- Committee on Evolutionary Biology, University of Chicago, 1025 E. 57th Street, Chicago, IL 60637, USA
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Republic of Panamá
| | - Gerald G. Carter
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Republic of Panamá
- Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, 318 W. 12th Ave, Columbus, OH 43210, USA
| | - Tanja K. Halczok
- Greifswald University, Zoological Institute and Museum, Soldmannstr. 14, 17489 Greifswald, Germany
| | - Gerald Kerth
- Greifswald University, Zoological Institute and Museum, Soldmannstr. 14, 17489 Greifswald, Germany
| | - Rachel A. Page
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Republic of Panamá
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8
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9
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Geographic variation of contact calls suggest distinct modes of vocal transmission in a leaf-roosting bat. Behav Ecol Sociobiol 2018. [DOI: 10.1007/s00265-018-2543-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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10
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Blyton MDJ, Banks SC, Peakall R. The effect of sex-biased dispersal on opposite-sexed spatial genetic structure and inbreeding risk. Mol Ecol 2015; 24:1681-95. [PMID: 25761248 DOI: 10.1111/mec.13149] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 03/05/2015] [Accepted: 03/06/2015] [Indexed: 11/29/2022]
Abstract
Natal sex-biased dispersal has long been thought to reduce the risk of inbreeding by spatially separating opposite-sexed kin. Yet, comprehensive and quantitative evaluations of this hypothesis are lacking. In this study, we quantified the effectiveness of sex-biased dispersal as an inbreeding avoidance strategy by combining spatially explicit simulations and empirical data. We quantified the extent of kin clustering by measuring the degree of spatial autocorrelation among opposite-sexed individuals (FM structure). This allowed us to systematically explore how the extent of sex-biased dispersal, generational overlap, and mate searching distance, influenced both kin clustering, and the resulting inbreeding in the absence of complementary inbreeding avoidance strategies. Simulations revealed that when sex-biased dispersal was limited, positive FM genetic structure developed quickly and increased as the mate searching distance decreased or as generational overlap increased. Interestingly, complete long-range sex-biased dispersal did not prevent the development of FM genetic structure when generations overlapped. We found a very strong correlation between FM genetic structure and both FIS under random mating, and pedigree-based measures of inbreeding. Thus, we show that the detection of FM genetic structure can be a strong indicator of inbreeding risk. Empirical data for two species with different life history strategies yielded patterns congruent with our simulations. Our study illustrates a new application of spatial genetic autocorrelation analysis that offers a framework for quantifying the risk of inbreeding that is easily extendable to other species. Furthermore, our findings provide other researchers with a context for interpreting observed patterns of opposite-sexed spatial genetic structure.
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Affiliation(s)
- Michaela D J Blyton
- Evolution, Ecology and Genetics, Research School of Biology, The Australian National University, Acton, ACT, 2601, Australia; The Fenner School of Environment and Society, The Australian National University, Acton, ACT, 2601, Australia
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11
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Chaverri G, Gillam EH. Repeatability in the contact calling system of Spix's disc-winged bat (Thyroptera tricolor). ROYAL SOCIETY OPEN SCIENCE 2015; 2:140197. [PMID: 26064578 PMCID: PMC4448792 DOI: 10.1098/rsos.140197] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 12/22/2014] [Indexed: 06/04/2023]
Abstract
Spix's disc-winged bat (Thyroptera tricolor) forms cohesive groups despite using an extremely ephemeral roost, partly due to the use of two acoustic signals that help individuals locate roost sites and group members. While the calls that aid in group cohesion are commonly used, some bats rarely or never produce them. Here, we examine whether the differences observed in the contact calling behaviour of T. tricolor are repeatable; that is, whether individual differences are consistent. We recorded contact calls of individuals in the field and rates and patterns of vocalization. To determine whether measured variables were consistent within individuals, we estimated repeatability (R), which compares within-individual to among-individual variance in behavioural traits. Our results show that repeatability for call variables was moderate but significant, and that repeatability was highest for the average number of calls produced (R=0.46-0.49). Our results demonstrate important individual differences in the contact calling behaviour of T. tricolor; we discuss how these could be the result of mechanisms such as frequency-dependent selection that favour groups composed of individuals with diverse vocal strategies. Future work should address whether changes in social environment, specifically group membership and social status, affect vocal behaviour.
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Affiliation(s)
| | - Erin H. Gillam
- Department of Biological Sciences, North Dakota State University, Fargo, ND 58108, USA
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12
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Dispersal and social organization in the Neotropical Grey sac-winged bat Balantiopteryx plicata. Behav Ecol Sociobiol 2014. [DOI: 10.1007/s00265-014-1702-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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13
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Kessler SE, Radespiel U, Hasiniaina AIF, Leliveld LMC, Nash LT, Zimmermann E. Modeling the origins of mammalian sociality: moderate evidence for matrilineal signatures in mouse lemur vocalizations. Front Zool 2014; 11:14. [PMID: 24555438 PMCID: PMC3936920 DOI: 10.1186/1742-9994-11-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 02/11/2014] [Indexed: 11/10/2022] Open
Abstract
INTRODUCTION Maternal kin selection is a driving force in the evolution of mammalian social complexity and it requires that kin are distinctive from nonkin. The transition from the ancestral state of asociality to the derived state of complex social groups is thought to have occurred via solitary foraging, in which individuals forage alone, but, unlike the asocial ancestors, maintain dispersed social networks via scent-marks and vocalizations. We hypothesize that matrilineal signatures in vocalizations were an important part of these networks. We used the solitary foraging gray mouse lemur (Microcebus murinus) as a model for ancestral solitary foragers and tested for matrilineal signatures in their calls, thus investigating whether such signatures are already present in solitary foragers and could have facilitated the kin selection thought to have driven the evolution of increased social complexity in mammals. Because agonism can be very costly, selection for matrilineal signatures in agonistic calls should help reduce agonism between unfamiliar matrilineal kin. We conducted this study on a well-studied population of wild mouse lemurs at Ankarafantsika National Park, Madagascar. We determined pairwise relatedness using seven microsatellite loci, matrilineal relatedness by sequencing the mitrochondrial D-loop, and sleeping group associations using radio-telemetry. We recorded agonistic calls during controlled social encounters and conducted a multi-parametric acoustic analysis to determine the spectral and temporal structure of the agonistic calls. We measured 10 calls for each of 16 females from six different matrilineal kin groups. RESULTS Calls were assigned to their matriline at a rate significantly higher than chance (pDFA: correct = 47.1%, chance = 26.7%, p = 0.03). There was a statistical trend for a negative correlation between acoustic distance and relatedness (Mantel Test: g = -1.61, Z = 4.61, r = -0.13, p = 0.058). CONCLUSIONS Mouse lemur agonistic calls are moderately distinctive by matriline. Because sleeping groups consisted of close maternal kin, both genetics and social learning may have generated these acoustic signatures. As mouse lemurs are models for solitary foragers, we recommend further studies testing whether the lemurs use these calls to recognize kin. This would enable further modeling of how kin recognition in ancestral species could have shaped the evolution of complex sociality.
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Affiliation(s)
- Sharon E Kessler
- Arizona State University, School of Human Evolution and Social Change, Box 872402, Tempe, AZ 85287-2402, USA
- University of Veterinary Medicine Hannover, Institute of Zoology, Bünteweg 17, 30559 Hannover, Germany
| | - Ute Radespiel
- University of Veterinary Medicine Hannover, Institute of Zoology, Bünteweg 17, 30559 Hannover, Germany
| | | | - Lisette M C Leliveld
- University of Veterinary Medicine Hannover, Institute of Zoology, Bünteweg 17, 30559 Hannover, Germany
- Leibniz Institute for Farm Animal Biology (FBN), Institute for Behavioural Physiology, Wilhelm-Stahl-Allee 2, D-18196 Dummerstorf Germany
| | - Leanne T Nash
- Arizona State University, School of Human Evolution and Social Change, Box 872402, Tempe, AZ 85287-2402, USA
| | - Elke Zimmermann
- University of Veterinary Medicine Hannover, Institute of Zoology, Bünteweg 17, 30559 Hannover, Germany
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Buchalski MR, Chaverri G, Vonhof MJ. When genes move farther than offspring: gene flow by male gamete dispersal in the highly philopatric bat species Thyroptera tricolor. Mol Ecol 2013; 23:464-80. [PMID: 24237721 DOI: 10.1111/mec.12593] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Revised: 10/29/2013] [Accepted: 11/08/2013] [Indexed: 11/29/2022]
Abstract
For species characterized by philopatry of both sexes, mate selection represents an important behaviour for inbreeding avoidance, yet the implications for gene flow are rarely quantified. Here, we present evidence of male gamete-mediated gene flow resulting from extra-group mating in Spix's disc-winged bat, Thyroptera tricolor, a species which demonstrates all-offspring philopatry. We used microsatellite and capture-recapture data to characterize social group structure and the distribution of mated pairs at two sites in southwestern Costa Rica over four breeding seasons. Relatedness and genetic spatial autocorrelation analyses indicated strong kinship within groups and over short distances (<50 m), resulting from matrilineal group structure and small roosting home ranges (~0.2 ha). Despite high relatedness among-group members, observed inbreeding coefficients were low (FIS = 0.010 and 0.037). Parentage analysis indicated mothers and offspring belonged to the same social group, while fathers belonged to different groups, separated by large distances (~500 m) when compared to roosting home ranges. Simulated random mating indicated mate choice was not based on intermediate levels of relatedness, and mated pairs were less related than adults within social groups on average. Isolation-by-distance (IBD) models of genetic neighbourhood area based on father-offspring distances provided direct estimates of mean gamete dispersal distances (r^) > 10 roosting home range equivalents. Indirect estimates based on genetic distance provided even larger estimates of r^, indicating direct estimates were biased low. These results suggest extra-group mating reduces the incidence of inbreeding in T. tricolor, and male gamete dispersal facilitates gene flow in lieu of natal dispersal of young.
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Affiliation(s)
- M R Buchalski
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI, 49008, USA.,Veterinary Genetics Laboratory, University of California, Davis, Davis, CA, 95616, USA
| | - G Chaverri
- Universidad de Costa Rica, Golfito, 60701, Costa Rica
| | - M J Vonhof
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI, 49008, USA
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Chaverri G, Gillam EH, Kunz TH. A call-and-response system facilitates group cohesion among disc-winged bats. Behav Ecol 2012. [DOI: 10.1093/beheco/ars188] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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16
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Gillam EH, Chaverri G. Strong individual signatures and weaker group signatures in contact calls of Spix’s disc-winged bat, Thyroptera tricolor. Anim Behav 2012. [DOI: 10.1016/j.anbehav.2011.11.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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17
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Chaverri G, Kunz TH. Response of a specialist bat to the loss of a critical resource. PLoS One 2011; 6:e28821. [PMID: 22216118 PMCID: PMC3244425 DOI: 10.1371/journal.pone.0028821] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Accepted: 11/15/2011] [Indexed: 11/26/2022] Open
Abstract
Human activities have negatively impacted many species, particularly those with unique traits that restrict their use of resources and conditions to specific habitats. Unfortunately, few studies have been able to isolate the individual and combined effects of different threats on population persistence in a natural setting, since not all organisms can be associated with discrete habitat features occurring over limited spatial scales. We present the results of a field study that examines the short-term effects of roost loss in a specialist bat using a conspicuous, easily modified resource. We mimicked roost loss in the natural habitat and monitored individuals before and after the perturbation to determine patterns of resource use, spatial movements, and group stability. Our study focused on the disc-winged bat Thyroptera tricolor, a species highly morphologically specialized for roosting in the developing furled leaves of members of the order Zingiberales. We found that the number of species used for roosting increased, that home range size increased (before: mean 0.14±SD 0.08 ha; after: 0.73±0.68 ha), and that mean association indices decreased (before: 0.95±0.10; after: 0.77±0.18) once the roosting habitat was removed. These results demonstrate that the removal of roosting resources is associated with a decrease in roost-site preferences or selectivity, an increase in mobility of individuals, and a decrease in social cohesion. These responses may reduce fitness by potentially increasing energetic expenditure, predator exposure, and a decrease in cooperative interactions. Despite these potential risks, individuals never used roost-sites other than developing furled leaves, suggesting an extreme specialization that could ultimately jeopardize the long-term persistence of this species' local populations.
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Affiliation(s)
- Gloriana Chaverri
- Center for Ecology and Conservation Biology, Department of Biology, Boston University, Boston, Massachusetts, USA.
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