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Waiker P, de Abreu FCP, Luna-Lucena D, Freitas FCP, Simões ZLP, Rueppell O. Recombination mapping of the Brazilian stingless bee Frieseomelitta varia confirms high recombination rates in social hymenoptera. BMC Genomics 2021; 22:673. [PMID: 34536998 PMCID: PMC8449902 DOI: 10.1186/s12864-021-07987-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 09/04/2021] [Indexed: 11/26/2022] Open
Abstract
Background Meiotic recombination is a fundamental genetic process that shuffles allele combinations and promotes accurate segregation of chromosomes. Analyses of the ubiquitous variation of recombination rates within and across species suggest that recombination is evolving adaptively. All studied insects with advanced eusociality have shown exceptionally high recombination rates, which may represent a prominent case of adaptive evolution of recombination. However, our understanding of the relationship between social evolution and recombination rates is incomplete, partly due to lacking empirical data. Here, we present a linkage map of the monandrous, advanced eusocial Brazilian stingless bee, Frieseomelitta varia, providing the first recombination analysis in the diverse Meliponini (Hymenoptera, Apidae). Results Our linkage map includes 1417 markers in 19 linkage groups. This map spans approximately 2580 centimorgans, and comparisons to the physical genome assembly indicate that it covers more than 75 % of the 275 Megabasepairs (Mbp) F. varia genome. Thus, our study results in a genome-wide recombination rate estimate of 9.3–12.5 centimorgan per Mbp. This value is higher than estimates from nonsocial insects and comparable to other highly social species, although it does not support our prediction that monandry and strong queen-worker caste divergence of F. varia lead to even higher recombination rates than other advanced eusocial species. Conclusions Our study expands the association between elevated recombination and sociality in the order Hymenoptera and strengthens the support for the hypothesis that advanced social evolution in hymenopteran insects invariably selects for high genomic recombination rates. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07987-3.
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Affiliation(s)
- Prashant Waiker
- Biology Department, University of North Carolina at Greensboro, 321 McIver St, Greensboro, NC, 27412, USA.
| | - Fabiano Carlos Pinto de Abreu
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, SP, Ribeirão Preto, Brazil
| | - Danielle Luna-Lucena
- Departamento de Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Flávia Cristina Paula Freitas
- Departamento de Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.,Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal de Alfenas, Alfenas, MG, Brazil
| | - Zilá Luz Paulino Simões
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, SP, Ribeirão Preto, Brazil
| | - Olav Rueppell
- Biology Department, University of North Carolina at Greensboro, 321 McIver St, Greensboro, NC, 27412, USA.,Department of Biological Sciences, University of Alberta, AB, T6G 2E9, Edmonton, Canada
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DeLory T, Funderburk K, Miller K, Smith WZ, McPherson S, Pirk CW, Costa C, Teixeira ÉW, Dahle B, Rueppell O. Local Variation in Recombination Rates of the Honey Bee ( Apis mellifera) Genome among Samples from Six Disparate Populations. INSECTES SOCIAUX 2020; 67:127-138. [PMID: 33311731 PMCID: PMC7732154 DOI: 10.1007/s00040-019-00736-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Meiotic recombination is an essential component of eukaryotic sexual reproduction but its frequency varies within and between genomes. Although it is well-established that honey bees have a high recombination rate with about 20 cM/Mbp, the proximate and ultimate causes of this exceptional rate are poorly understood. Here, we describe six linkage maps of the Western Honey Bee Apis mellifera that were produced with consistent methodology from samples from distinct parts of the species' near global distribution. We compared the genome-wide rates and distribution of meiotic crossovers among the six maps and found considerable differences. Overall similarity of local recombination rates among our samples was unrelated to geographic or phylogenetic distance of the populations that our samples were derived from. However, the limited sampling constrains the interpretation of our results because it is unclear how representative these samples are. In contrast to previous studies, we found only in two datasets a significant relation between local recombination rate and GC content. Focusing on regions of particularly increased or decreased recombination in specific maps, we identified several enriched gene ontologies in these regions and speculate about their local adaptive relevance. These data are contributing to an increasing comparative effort to gain an understanding of the intra-specific variability of recombination rates and their evolutionary role in honey bees and other social insects.
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Affiliation(s)
- Timothy DeLory
- Department of Biology, University of North Carolina at Greensboro, NC, USA
- Current address: Department of Biology, Utah State University, 5305 Old Main Hill, Logan, UT, USA
| | - Karen Funderburk
- Department of Biology, University of North Carolina at Greensboro, NC, USA
- Current address: Applied Mathematics for the Life & Social Sciences, College of Liberal Arts and Sciences, Arizona State University, Tempe, AZ, USA
| | - Katelyn Miller
- Department of Biology, University of North Carolina at Greensboro, NC, USA
| | | | - Samantha McPherson
- Department of Biology, University of North Carolina at Greensboro, NC, USA
- Current address: Current address: NCSU Department of Entomology & Plant Pathology, Campus Box 7613, 100 Derieux Place, Raleigh, NC, USA
| | - Christian W. Pirk
- Social Insects Research Group, Department of Zoology & Entomology, University of Pretoria, South Africa
| | - Cecilia Costa
- Consiglio per la Ricerca in Agricolturae l’Analisi dell’Economia Agraria, Via Po, 14 - 00198 Rome, Italy
| | - Érica Weinstein Teixeira
- Honey Bee Health Specialized Laboratory, Biological Institute, São Paulo State Agribusiness Technology Agency, Av. Prof. Manoel César Ribeiro, 1920, Pindamonhangaba, São Paulo 12411-010, Brazil
| | - Bjørn Dahle
- Norwegian Beekeepers Association, Kløfta, Norway
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway
| | - Olav Rueppell
- Department of Biology, University of North Carolina at Greensboro, NC, USA
- Corresponding author: 312 Eberhart Bldg, 321 McIver Street, Greensboro NC 27403, USA. Phone: (+1) 336-2562591,
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3
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Rueppell O, Kuster R, Miller K, Fouks B, Rubio Correa S, Collazo J, Phaincharoen M, Tingek S, Koeniger N. A New Metazoan Recombination Rate Record and Consistently High Recombination Rates in the Honey Bee Genus Apis Accompanied by Frequent Inversions but Not Translocations. Genome Biol Evol 2018; 8:3653-3660. [PMID: 28173114 PMCID: PMC5521732 DOI: 10.1093/gbe/evw269] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/07/2016] [Indexed: 12/31/2022] Open
Abstract
Western honey bees (Apis mellifera) far exceed the commonly observed 1–2 meiotic recombination events per chromosome and exhibit the highest Metazoan recombination rate (20 cM/Mb) described thus far. However, the reasons for this exceptional rate of recombination are not sufficiently understood. In a comparative study, we report on the newly constructed genomic linkage maps of Apis florea and Apis dorsata that represent the two honey bee lineages without recombination rate estimates so far. Each linkage map was generated de novo, based on SNP genotypes of haploid male offspring of a single female. The A. florea map spans 4,782 cM with 1,279 markers in 16 linkage groups. The A. dorsata map is 5,762 cM long and contains 1,189 markers in 16 linkage groups. Respectively, these map sizes result in average recombination rate estimates of 20.8 and 25.1 cM/Mb. Synteny analyses indicate that frequent intra-chromosomal rearrangements but no translocations among chromosomes accompany the high rates of recombination during the independent evolution of the three major honey bee lineages. Our results imply a common cause for the evolution of very high recombination rates in Apis. Our findings also suggest that frequent homologous recombination during meiosis might increase ectopic recombination and rearrangements within but not between chromosomes. It remains to be investigated whether the resulting inversions may have been important in the evolutionary differentiation between honey bee species.
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Affiliation(s)
- Olav Rueppell
- Department of Biology, The University of North Carolina at Greensboro, Greensboro, NC, USA
| | - Ryan Kuster
- Department of Biology, The University of North Carolina at Greensboro, Greensboro, NC, USA
| | - Katelyn Miller
- Department of Biology, The University of North Carolina at Greensboro, Greensboro, NC, USA
| | - Bertrand Fouks
- Department of Biology, The University of North Carolina at Greensboro, Greensboro, NC, USA
| | - Sara Rubio Correa
- Department of Biology, The University of North Carolina at Greensboro, Greensboro, NC, USA
| | - Juan Collazo
- Department of Biology, The University of North Carolina at Greensboro, Greensboro, NC, USA
| | - Mananya Phaincharoen
- Ratchaburi Campus, King Mongkut's University of Technology Thonburi, Bangkok, Thailand
| | - Salim Tingek
- Agricultural Research Station, Tenom, Sabah, Malaysia
| | - Nikolaus Koeniger
- Molecular Ecology, Institute of Biology/Zoology, Martin-Luther-University Halle-Wittenberg, Halle an der Saale, Germany
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4
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Meunier J. Social immunity and the evolution of group living in insects. Philos Trans R Soc Lond B Biol Sci 2015; 370:20140102. [PMID: 25870389 PMCID: PMC4410369 DOI: 10.1098/rstb.2014.0102] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/02/2014] [Indexed: 01/25/2023] Open
Abstract
The evolution of group living requires that individuals limit the inherent risks of parasite infection. To this end, group living insects have developed a unique capability of mounting collective anti-parasite defences, such as allogrooming and corpse removal from the nest. Over the last 20 years, this phenomenon (called social immunity) was mostly studied in eusocial insects, with results emphasizing its importance in derived social systems. However, the role of social immunity in the early evolution of group living remains unclear. Here, I investigate this topic by first presenting the definitions of social immunity and discussing their applications across social systems. I then provide an up-to-date appraisal of the collective and individual mechanisms of social immunity described in eusocial insects and show that they have counterparts in non-eusocial species and even solitary species. Finally, I review evidence demonstrating that the increased risks of parasite infection in group living species may both decrease and increase the level of personal immunity, and discuss how the expression of social immunity could drive these opposite effects. By highlighting similarities and differences of social immunity across social systems, this review emphasizes the potential importance of this phenomenon in the early evolution of the multiple forms of group living in insects.
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Affiliation(s)
- Joël Meunier
- Zoological Institute, Evolutionary Biology, Johannes Gutenberg University Mainz, Mainz, Germany
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5
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Carabajal Paladino L, Muntaabski I, Lanzavecchia S, Le Bagousse-Pinguet Y, Viscarret M, Juri M, Fueyo-Sánchez L, Papeschi A, Cladera J, Bressa MJ. Complementary sex determination in the parasitic wasp Diachasmimorpha longicaudata. PLoS One 2015; 10:e0119619. [PMID: 25789748 PMCID: PMC4366257 DOI: 10.1371/journal.pone.0119619] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 01/27/2015] [Indexed: 11/18/2022] Open
Abstract
We studied the sex determination in Diachasmimorpha longicaudata, a parasitoid braconid wasp widely used as biological control agent of fruit pest tephritid flies. We tested the complementary sex determination hypothesis (CSD) known in at least 60 species of Hymenoptera. According to CSD, male or female development depends on the allelic composition of one sex locus (single-locus CSD) or multiple sex loci (multiple-locus CSD). Hemizygote individuals are normal haploid males, and heterozygotes for at least one sex locus are normal diploid females, but homozygotes for all the sex loci are diploid males. In order to force the occurrence of diploid males in D. longicaudata, we established highly inbred lines and examined their offspring using chromosome counting, flow cytometry, and sex ratio analysis. We found that when mother-son crosses were studied, this wasp produced about 20% of diploid males out of the total male progeny. Our results suggest that this parasitoid may represent the second genus with multiple-locus CSD in Hymenoptera. Knowledge about the sex determination system in D. longicaudata is relevant for the improvement of mass rearing protocols of this species. This information also provides the necessary background for further investigations on the underlying molecular mechanisms of sex determination in this species, and a better insight into the evolution of this pathway in Hymenoptera in particular and insects in general.
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Affiliation(s)
- Leonela Carabajal Paladino
- Institute of Entomology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Czech Republic
- Instituto de Genética “Ewald A Favret,” Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina
- * E-mail:
| | - Irina Muntaabski
- Instituto de Genética “Ewald A Favret,” Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina
| | - Silvia Lanzavecchia
- Instituto de Genética “Ewald A Favret,” Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina
| | | | - Mariana Viscarret
- Instituto de Microbiología y Zoología Agrícola, Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina
| | - Marianela Juri
- Instituto de Genética “Ewald A Favret,” Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
| | - Luciana Fueyo-Sánchez
- Instituto de Ecología y Desarrollo Sustentable, Universidad Nacional de Luján, Luján, Argentina
| | - Alba Papeschi
- Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
- Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
| | - Jorge Cladera
- Instituto de Genética “Ewald A Favret,” Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina
| | - María José Bressa
- Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
- Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
- Instituto de Ecología, Genética y Evolución de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
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6
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Ross CR, DeFelice DS, Hunt GJ, Ihle KE, Amdam GV, Rueppell O. Genomic correlates of recombination rate and its variability across eight recombination maps in the western honey bee (Apis mellifera L.). BMC Genomics 2015; 16:107. [PMID: 25765996 PMCID: PMC4339005 DOI: 10.1186/s12864-015-1281-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 01/26/2015] [Indexed: 12/02/2022] Open
Abstract
Background Meiotic recombination has traditionally been explained based on the structural requirement to stabilize homologous chromosome pairs to ensure their proper meiotic segregation. Competing hypotheses seek to explain the emerging findings of significant heterogeneity in recombination rates within and between genomes, but intraspecific comparisons of genome-wide recombination patterns are rare. The honey bee (Apis mellifera) exhibits the highest rate of genomic recombination among multicellular animals with about five cross-over events per chromatid. Results Here, we present a comparative analysis of recombination rates across eight genetic linkage maps of the honey bee genome to investigate which genomic sequence features are correlated with recombination rate and with its variation across the eight data sets, ranging in average marker spacing ranging from 1 Mbp to 120 kbp. Overall, we found that GC content explained best the variation in local recombination rate along chromosomes at the analyzed 100 kbp scale. In contrast, variation among the different maps was correlated to the abundance of microsatellites and several specific tri- and tetra-nucleotides. Conclusions The combined evidence from eight medium-scale recombination maps of the honey bee genome suggests that recombination rate variation in this highly recombining genome might be due to the DNA configuration instead of distinct sequence motifs. However, more fine-scale analyses are needed. The empirical basis of eight differing genetic maps allowed for robust conclusions about the correlates of the local recombination rates and enabled the study of the relation between DNA features and variability in local recombination rates, which is particularly relevant in the honey bee genome with its exceptionally high recombination rate. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1281-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Caitlin R Ross
- Department of Computer Sciences, The University of North Carolina at Greensboro, Greensboro, NC, 27402, USA.
| | - Dominick S DeFelice
- Department of Biology, 312 Eberhart Building, The University of North Carolina at Greensboro, 321 McIver Street, Greensboro, NC, 27402, USA.
| | - Greg J Hunt
- Department of Entomology, Purdue University, West Lafayette, IN, 47907, USA.
| | - Kate E Ihle
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287, USA.
| | - Gro V Amdam
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287, USA. .,Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, 1432, Aas, Norway.
| | - Olav Rueppell
- Department of Biology, 312 Eberhart Building, The University of North Carolina at Greensboro, 321 McIver Street, Greensboro, NC, 27402, USA.
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7
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Ross L, Blackmon H, Lorite P, Gokhman VE, Hardy NB. Recombination, chromosome number and eusociality in the Hymenoptera. J Evol Biol 2015; 28:105-16. [PMID: 25382409 PMCID: PMC4328152 DOI: 10.1111/jeb.12543] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 10/31/2014] [Accepted: 11/03/2014] [Indexed: 02/05/2023]
Abstract
Extraordinarily high rates of recombination have been observed in some eusocial species. The most popular explanation is that increased recombination increases genetic variation among workers, which in turn increases colony performance, for example by increasing parasite resistance. However, support for the generality of higher recombination rates among eusocial organisms remains weak, due to low sample size and a lack of phylogenetic independence of observations. Recombination rate, although difficult to measure directly, is correlated with chromosome number. As predicted, several authors have noted that chromosome numbers are higher among the eusocial species of Hymenoptera (ants, bees and wasps). Here, we present a formal comparative analysis of karyotype data from 1567 species of Hymenoptera. Contrary to earlier studies, we find no evidence for an absolute difference between chromosome number in eusocial and solitary species of Hymenoptera. However, we find support for an increased rate of chromosome number change in eusocial taxa. We show that among eusocial taxa colony size is able to explain some of the variation in chromosome number: intermediate-sized colonies have more chromosomes than those that are either very small or very large. However, we were unable to detect effects of a number of other colony characteristics predicted to affect recombination rate - including colony relatedness and caste number. Taken together, our results support the view that a eusocial lifestyle has led to variable selection pressure for increased recombination rates, but that identifying the factors contributing to this variable selection will require further theoretical and empirical effort.
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Affiliation(s)
- L Ross
- School of Biological Sciences, Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK
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8
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Soper DM, King KC, Vergara D, Lively CM. Exposure to parasites increases promiscuity in a freshwater snail. Biol Lett 2014; 10:20131091. [PMID: 24759366 PMCID: PMC4013694 DOI: 10.1098/rsbl.2013.1091] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 03/26/2014] [Indexed: 11/12/2022] Open
Abstract
Under the Red Queen hypothesis, outcrossing can produce genetically variable progeny, which may be more resistant, on average, to locally adapted parasites. Mating with multiple partners may enhance this resistance by further increasing the genetic variation among offspring. We exposed Potamopyrgus antipodarum to the eggs of a sterilizing, trematode parasite and tested whether this altered mating behaviour. We found that exposure to parasites increased the number of snail mating pairs and the total number of different mating partners for both males and females. Thus, our results suggest that, in host populations under parasite-mediated selection, exposure to infective propagules increases the rate of mating and the number of mates.
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Affiliation(s)
- D M Soper
- Department of Biology, Indiana University, , Bloomington, IN, USA
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9
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Jeanson R, Weidenmüller A. Interindividual variability in social insects - proximate causes and ultimate consequences. Biol Rev Camb Philos Soc 2013; 89:671-87. [PMID: 24341677 DOI: 10.1111/brv.12074] [Citation(s) in RCA: 151] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 11/15/2013] [Accepted: 11/19/2013] [Indexed: 12/20/2022]
Abstract
Individuals within social groups often show consistent differences in behaviour across time and context. Such interindividual differences and the evolutionary challenge they present have recently generated considerable interest. Social insects provide some of the most familiar and spectacular examples of social groups with large interindividual differences. Investigating these within-group differences has a long research tradition, and behavioural variability among the workers of a colony is increasingly regarded as fundamental for a key feature of social insects: division of labour. The goal of this review is to illustrate what we know about both the proximate mechanisms underlying behavioural variability among the workers of a colony and its ultimate consequences; and to highlight the many open questions in this research field. We begin by reviewing the literature on mechanisms that potentially introduce, maintain, and adjust the behavioural differentiation among workers. We highlight the fact that so far, most studies have focused on behavioural variability based on genetic variability, provided by e.g. multiple mating of the queen, while other mechanisms that may be responsible for the behavioural differentiation among workers have been largely neglected. These include maturational, nutritional and environmental influences. We further discuss how feedback provided by the social environment and learning and experience of adult workers provides potent and little-explored sources of differentiation. In a second part, we address what is known about the potential benefits and costs of increased behavioural variability within the workers of a colony. We argue that all studies documenting a benefit of variability so far have done so by manipulating genetic variability, and that a direct test of the effect of behavioural variability on colony productivity has yet to be provided. We emphasize that the costs associated with interindividual variability have been largely overlooked, and that a better knowledge of the cost/benefit balance of behavioural variability is crucial for our understanding of the evolution of the mechanisms underlying the social organization of insect societies. We conclude by highlighting what we believe to be promising but little-explored avenues for future research on how within-colony variability has evolved and is maintained. We emphasize the need for comparative studies and point out that, so far, most studies on interindividual variability have focused on variability in individual response thresholds, while the significance of variability in other parameters of individual response, such as probability and intensity of the response, has been largely overlooked. We propose that these parameters have important consequences for the colony response. Much more research is needed to understand if and how interindividual variability is modulated in order to benefit division of labour, homeostasis and ultimately colony fitness in social insects.
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Affiliation(s)
- Raphaël Jeanson
- Centre National de la Recherche Scientifique, Centre de Recherches sur la Cognition Animale, 118 Route de Narbonne, 31062 Cedex 9, Toulouse, France; Centre de Recherches sur la Cognition Animale, Université Paul Sabatier, 118 Route de Narbonne, 31062 Cedex 9, Toulouse, France
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10
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Abstract
Eusocial Hymenoptera, such as the European honey bee, Apis mellifera, have the highest recombination rates of multicellular animals.(1) Recently, we showed(2) that a side-effect of recombination in the honey bee, GC biased gene conversion (bGC), helps maintain the unusual bimodal GC-content distribution of the bee genome by increasing GC-content in high recombination areas while low recombination areas are losing GC-content because of biased AT mutations and low rates of bGC. Although the very high recombination rate of A. mellifera makes GC-content evolution easier to study, the pattern is consistent with results found in many other species including mammals and yeast.(3) Also consistent across phyla is the association of higher genetic diversity and divergence with high GC and high recombination areas.(4) (,) (5) Finally, we showed that genes overexpressed in the brains of workers cluster in GC-rich genomic areas with the highest rates of recombination and molecular evolution.(2) In this Addendum we present a conceptual model of how eusociality and high recombination rates may co-evolve.
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Affiliation(s)
- Clement F Kent
- Department of Biology; York University; Toronto, ON Canada
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