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Kivelä SM, Välimäki P, Gotthard K. SEASONALITY MAINTAINS ALTERNATIVE LIFE-HISTORY PHENOTYPES. Evolution 2013; 67:3145-60. [DOI: 10.1111/evo.12181] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 05/31/2013] [Indexed: 12/26/2022]
Affiliation(s)
- Sami M. Kivelä
- Department of Biology; University of Oulu; PO Box 3000 90014 University of Oulu Finland
- Current address: Department of Zoology; Stockholm University; SE-10691 Stockholm Sweden
| | - Panu Välimäki
- Department of Biology; University of Oulu; PO Box 3000 90014 University of Oulu Finland
| | - Karl Gotthard
- Department of Zoology; Stockholm University; SE-10691 Stockholm Sweden
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202
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De Loof A, Boerjan B, Ernst UR, Schoofs L. The mode of action of juvenile hormone and ecdysone: towards an epi-endocrinological paradigm? Gen Comp Endocrinol 2013; 188:35-45. [PMID: 23454668 DOI: 10.1016/j.ygcen.2013.02.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 02/07/2013] [Accepted: 02/12/2013] [Indexed: 12/20/2022]
Abstract
In some insect species, two sites of juvenile hormone (JH) synthesis have been reported: the very well documented corpora allata that secrete JH for "general use", and the reproductive system, in particular the male accessory glands, in which the function of the sometimes huge amounts of JH (e.g. in Hyalophora cecropia) remains to be clarified. A recent finding in Schistocerca gregaria, namely that suppression of the ecdysteroid peak preceding a molt by RNAi of the Halloween genes spook, phantom and shade does not impede normal molting, challenges the (never experimentally proven) classical concept that such a peak is causally linked to a molt. Recent developments in epigenetic control of gene expression in both the honey bee and in locusts suggest that, in addition to the classical scheme of hormone-receptor (membrane- and/or nuclear) mode of action, there may be a third way. Upon combining these and other orphan data that do not fit in the commonly accepted textbook schemes, we here advance the working hypothesis that both JH and ecdysone might be important but overlooked players in epigenetic control of gene expression, in particular at extreme concentrations (peak values or total absence). In this review, we put forward how epi-endocrinology can complement classical arthropod endocrinology.
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Affiliation(s)
- Arnold De Loof
- Research Group of Functional Genomics and Proteomics, KU Leuven, Naamsestraat 59, Bus 2465, 3000 Leuven, Belgium.
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203
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Kirk H, Dorn S, Mazzi D. Molecular genetics and genomics generate new insights into invertebrate pest invasions. Evol Appl 2013; 6:842-856. [PMID: 29387170 PMCID: PMC5779122 DOI: 10.1111/eva.12071] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 02/28/2013] [Indexed: 01/08/2023] Open
Abstract
Invertebrate pest invasions and outbreaks are associated with high social, economic, and ecological costs, and their significance will intensify with an increasing pressure on agricultural productivity as a result of human population growth and climate change. New molecular genetic and genomic techniques are available and accessible, but have been grossly underutilized in studies of invertebrate pest invasions, despite that they are useful tools for applied pest management and for understanding fundamental features of pest invasions including pest population demographics and adaptation of pests to novel and/or changing environments. Here, we review current applications of molecular genetics and genomics in the study of invertebrate pest invasions and outbreaks, and we highlight shortcomings from the current body of research. We then discuss recent conceptual and methodological advances in the areas of molecular genetics/genomics and data analysis, and we highlight how these advances will further our understanding of the demographic, ecological, and evolutionary features of invertebrate pest invasions. We are now well equipped to use molecular data to understand invertebrate dispersal and adaptation, and this knowledge has valuable applications in agriculture at a time when these are critically required.
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Affiliation(s)
- Heather Kirk
- ETH ZurichInstitute of Agricultural Sciences, Applied EntomologyZurichSwitzerland
- Present address:
University of ZurichInstitute of Systematic BotanyZurichSwitzerland
| | - Silvia Dorn
- ETH ZurichInstitute of Agricultural Sciences, Applied EntomologyZurichSwitzerland
| | - Dominique Mazzi
- ETH ZurichInstitute of Agricultural Sciences, Applied EntomologyZurichSwitzerland
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204
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Interplay between insulin signaling, juvenile hormone, and vitellogenin regulates maternal effects on polyphenism in ants. Proc Natl Acad Sci U S A 2013; 110:11050-5. [PMID: 23754378 DOI: 10.1073/pnas.1221781110] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Polyphenism is the phenomenon in which alternative phenotypes are produced by a single genotype in response to environmental cues. An extreme case is found in social insects, in which reproductive queens and sterile workers that greatly differ in morphology and behavior can arise from a single genotype. Experimental evidence for maternal effects on caste determination, the differential larval development toward the queen or worker caste, was recently documented in Pogonomyrmex seed harvester ants, in which only colonies with a hibernated queen produce new queens. However, the proximate mechanisms behind these intergenerational effects have remained elusive. We used a combination of artificial hibernation, hormonal treatments, gene expression analyses, hormone measurements, and vitellogenin quantification to investigate how the combined effect of environmental cues and hormonal signaling affects the process of caste determination in Pogonomyrmex rugosus. The results show that the interplay between insulin signaling, juvenile hormone, and vitellogenin regulates maternal effects on the production of alternative phenotypes and set vitellogenin as a likely key player in the intergenerational transmission of information. This study reveals how hibernation triggers the production of new queens in Pogonomyrmex ant colonies. More generally, it provides important information on maternal effects by showing how environmental cues experienced by one generation can translate into phenotypic variation in the next generation.
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205
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Nylin S. Induction of diapause and seasonal morphs in butterflies and other insects: knowns, unknowns and the challenge of integration. PHYSIOLOGICAL ENTOMOLOGY 2013; 38:96-104. [PMID: 23894219 PMCID: PMC3712473 DOI: 10.1111/phen.12014] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/16/2013] [Indexed: 05/26/2023]
Abstract
The 'choice' of whether to enter diapause or to develop directly has profound effects on the life histories of insects, and may thus have cascading consequences such as seasonal morphs and other less obvious forms of seasonal plasticity. Present knowledge of the control of diapause and seasonal morphs at the physiological and molecular levels is briefly reviewed. Examples, mainly derived from personal research (primarily on butterflies), are given as a starting point with the aim of outlining areas of research that are still poorly understood. These include: the role of the direction of change in photoperiod; the role of factors such as temperature and diet in modifying the photoperiodic responses; and the role of sex, parental effects and sex linkage on photoperiodic control. More generally, there is still a limited understanding of how external cues and physiological pathways regulating various traits are interconnected via gene action to form a co-adapted complete phenotype that is adaptive in the wild despite environmental fluctuation and change.
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Affiliation(s)
- Sören Nylin
- Department of Zoology, Stockholm University Stockholm, Sweden
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206
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Uzsák A, Schal C. Social interaction facilitates reproduction in male German cockroaches, Blattella germanica. Anim Behav 2013. [DOI: 10.1016/j.anbehav.2013.04.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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207
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Sandre SL, Kaasik A, Eulitz U, Tammaru T. Phenotypic plasticity in a generalist insect herbivore with the combined use of direct and indirect cues. OIKOS 2013. [DOI: 10.1111/j.1600-0706.2013.00504.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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208
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Glastad KM, Hunt BG, Goodisman MAD. Evidence of a conserved functional role for DNA methylation in termites. INSECT MOLECULAR BIOLOGY 2013; 22:143-154. [PMID: 23278917 DOI: 10.1111/imb.12010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Many organisms are capable of developing distinct phenotypes from the same genotype. This developmental plasticity is particularly prevalent in insects, which can produce alternate adaptive forms in response to distinct environmental cues. The ability to develop divergent phenotypes from the same genotype often relies on epigenetic information, which affects gene function and is transmitted through cell divisions. One of the most important epigenetic marks, DNA methylation, has been lost in several insect lineages, yet its taxonomic distribution and functional conservation remain uninvestigated in many taxa. In the present study, we demonstrate that the signature of high levels of DNA methylation exists in the expressed genes of two termites, Reticulitermes flavipes and Coptotermes formosanus. Further, we show that DNA methylation is preferentially targeted to genes with ubiquitous expression among morphs. Functional associations of DNA methylation are also similar to those observed in other invertebrate taxa with functional DNA methylation systems. Finally, we demonstrate an association between DNA methylation and the long-term evolutionary conservation of genes. Overall, our findings strongly suggest DNA methylation is present at particularly high levels in termites and may play similar roles to those found in other insects.
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Affiliation(s)
- K M Glastad
- School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA
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209
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Mehrparvar M, Zytynska SE, Weisser WW. Multiple cues for winged morph production in an aphid metacommunity. PLoS One 2013; 8:e58323. [PMID: 23472179 PMCID: PMC3589340 DOI: 10.1371/journal.pone.0058323] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Accepted: 02/02/2013] [Indexed: 11/19/2022] Open
Abstract
Environmental factors can lead individuals down different developmental pathways giving rise to distinct phenotypes (phenotypic plasticity). The production of winged or unwinged morphs in aphids is an example of two alternative developmental pathways. Dispersal is paramount in aphids that often have a metapopulation structure, where local subpopulations frequently go extinct, such as the specialized aphids on tansy (Tanacetum vulgare). We conducted various experiments to further understand the cues involved in the production of winged dispersal morphs by the two dominant species of the tansy aphid metacommunity, Metopeurum fuscoviride and Macrosiphoniella tanacetaria. We found that the ant-tended M. fuscoviride produced winged individuals predominantly at the beginning of the season while the untended M. tanacetaria produced winged individuals throughout the season. Winged mothers of both species produced winged offspring, although in both species winged offspring were mainly produced by unwinged females. Crowding and the presence of predators, effects already known to influence wing production in other aphid species, increased the percentage of winged offspring in M. tanacetaria, but not in M. fuscoviride. We find there are also other factors (i.e. temporal effects) inducing the production of winged offspring for natural aphid populations. Our results show that the responses of each aphid species are due to multiple wing induction cues.
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Affiliation(s)
- Mohsen Mehrparvar
- Terrestrial Ecology, Department of Ecology and Ecosystem Management, Center for Life and Food Sciences Weihenstephan, Technische Universität München, Freising, Germany.
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210
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Zeh JA, Zeh DW. On the threshold of dispersal: hitchhiking on a giant fly favours exaggerated male traits in a male-dimorphic pseudoscorpion. Biol J Linn Soc Lond 2013. [DOI: 10.1111/bij.12011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jeanne A. Zeh
- Department of Biology and Program in Ecology, Evolution and Conservation Biology; University of Nevada, Reno; Reno NV 89557 USA
| | - David W. Zeh
- Department of Biology and Program in Ecology, Evolution and Conservation Biology; University of Nevada, Reno; Reno NV 89557 USA
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211
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Plesnar-Bielak A, Jawor A, Kramarz PE. Complex response in size-related traits of the bulb mites (Rhizoglyphus robini) in elevated thermal conditions - an experimental evolution approach. J Exp Biol 2013; 216:4542-8. [DOI: 10.1242/jeb.090951] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Summary
Temperature is a key environmental factor affecting almost all aspects of life histories in ectotherms. The theory predicts that they grow faster, reach smaller sizes and produce smaller offspring when temperature increases. In addition, temperature changes, through their effects on metabolism, may also influence the expression of alternative reproductive phenotypes (ARP) in ectotherms. Although many studies investigated phenotypic plasticity of life history traits in relation to temperature change, little is known about how those traits and phenotypic plasticity may evolve together. In our study we subjected the bulb mites (non-model, soil organisms that normally experience rather stable thermal conditions) to experimental evolution in two temperature treatments: control (24°C) and elevated (28°C). After 18 generations we measured adult body size, eggs size and development time of both treatments at control as well as at elevated temperature (test temperatures). Thus, we were able to detect genetic changes (the effect of selection temperature) and environmental effects (the effects of test temperature). We also observed the ARP expression throughout the experimental evolution. Our results revealed quite complex patterns of life history in traits response to temperature. Mites developed faster and reached smaller sizes at increased temperature, but evolutionary responses to increased temperature were not always parallel to the observed phenotypic plasticity. Additionally, despite smaller body sizes females laid larger eggs at higher temperature. This effect was more pronounced in animals evolving at elevated temperature. Evolution at increased temperature affected also ARP expression with the proportion of armored fighters decreasing from generation to generation. We propose that this could be the consequence of temperature sensitivity of cost to benefits ratio of the expressing ARPs.
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212
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Penick CA, Prager SS, Liebig J. Juvenile hormone induces queen development in late-stage larvae of the ant Harpegnathos saltator. JOURNAL OF INSECT PHYSIOLOGY 2012; 58:1643-1649. [PMID: 23073393 DOI: 10.1016/j.jinsphys.2012.10.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 09/28/2012] [Accepted: 10/01/2012] [Indexed: 06/01/2023]
Abstract
A link between hormones and developmental plasticity has long been established, but understanding how evolution has shaped the physiological systems underlying plasticity remains a major question. Within the eusocial insects, developmental plasticity helps define a reproductive division of labor through the production of distinct queen and worker castes. Caste determination may be triggered via changes in juvenile hormone (JH) levels during specific JH-sensitive periods in development. The timing of these periods, however, can vary and may relate to phenotypic differences observed among species. In order to gain insight into the evolution of caste determining systems in eusocial insects, we investigated the presence of a JH-sensitive period for queen determination in the ant Harpegnathos saltator. This species displays a number of ancestral characteristics, including low queen-worker dimorphism, and should allow insight into the early evolution of caste determining systems in ants. We identified four larval instars in H. saltator, and we found that the application of a JH analog (JHA) to third and fourth instar larvae induced queen development while treatment of early instars did not. This indicated the presence of a JH-sensitive period for queen determination at the end of the larval stage. These results contrast with what has been found in other ant species, where queen determination occurs much earlier in development. Therefore, our results suggest that caste determination originally occurred late in the larval stage in the ancestral condition but has shifted earlier in development in species that began to acquire advanced characteristics. This shift may have facilitated the development of greater queen-worker dimorphism as well as multiple worker castes.
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Affiliation(s)
- Clint A Penick
- School of Life Sciences, Arizona State University, Tempe, AZ 85287-4501, USA.
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213
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Morehouse NI, Mandon N, Christides JP, Body M, Bimbard G, Casas J. Seasonal selection and resource dynamics in a seasonally polyphenic butterfly. J Evol Biol 2012. [DOI: 10.1111/jeb.12051] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- N. I. Morehouse
- Institut de Recherche sur la Biologie de l'Insecte; UMR CNRS 7261; Université de Tours; Tours France
- Department of Biological Sciences; University of Pittsburgh; Pittsburgh PA USA
| | - N. Mandon
- Institut de Recherche sur la Biologie de l'Insecte; UMR CNRS 7261; Université de Tours; Tours France
| | - J.-P. Christides
- Institut de Recherche sur la Biologie de l'Insecte; UMR CNRS 7261; Université de Tours; Tours France
| | - M. Body
- Institut de Recherche sur la Biologie de l'Insecte; UMR CNRS 7261; Université de Tours; Tours France
| | - G. Bimbard
- Institut de Recherche sur la Biologie de l'Insecte; UMR CNRS 7261; Université de Tours; Tours France
| | - J. Casas
- Institut de Recherche sur la Biologie de l'Insecte; UMR CNRS 7261; Université de Tours; Tours France
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214
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Kapheim KM, Smith AR, Nonacs P, Wcislo WT, Wayne RK. Foundress polyphenism and the origins of eusociality in a facultatively eusocial sweat bee, Megalopta genalis (Halictidae). Behav Ecol Sociobiol 2012. [DOI: 10.1007/s00265-012-1453-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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215
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Johansson F, Nilsson-Örtman V. Predation and the relative importance of larval colour polymorphisms and colour polyphenism in a damselfly. Evol Ecol 2012. [DOI: 10.1007/s10682-012-9617-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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216
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Raubenheimer D, Simpson SJ, Tait AH. Match and mismatch: conservation physiology, nutritional ecology and the timescales of biological adaptation. Philos Trans R Soc Lond B Biol Sci 2012; 367:1628-46. [PMID: 22566672 DOI: 10.1098/rstb.2012.0007] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Conservation physiology (CP) and nutritional ecology (NE) are both integrative sciences that share the fundamental aim of understanding the patterns, mechanisms and consequences of animal responses to changing environments. Here, we explore the high-level similarities and differences between CP and NE, identifying as central themes to both fields the multiple timescales over which animals adapt (and fail to adapt) to their environments, and the need for integrative models to study these processes. At one extreme are the short-term regulatory responses that modulate the state of animals in relation to the environment, which are variously considered under the concepts of homeostasis, homeorhesis, enantiostasis, heterostasis and allostasis. In the longer term are developmental responses, including phenotypic plasticity and transgenerational effects mediated by non-genomic influences such as parental physiology, epigenetic effects and cultural learning. Over a longer timescale still are the cumulative genetic changes that take place in Darwinian evolution. We present examples showing how the adaptive responses of animals across these timescales have been represented in an integrative framework from NE, the geometric framework (GF) for nutrition, and close with an illustration of how GF can be applied to the central issue in CP, animal conservation.
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Affiliation(s)
- David Raubenheimer
- Nutritional Ecology Research Group, Massey University, Albany, New Zealand.
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217
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Buzatto BA, Tomkins JL, Simmons LW. Maternal effects on male weaponry: female dung beetles produce major sons with longer horns when they perceive higher population density. BMC Evol Biol 2012; 12:118. [PMID: 22823456 PMCID: PMC3506554 DOI: 10.1186/1471-2148-12-118] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 06/29/2012] [Indexed: 11/17/2022] Open
Abstract
Background Maternal effects are environmental influences on the phenotype of one individual that are due to the expression of genes in its mother, and are expected to evolve whenever females are better capable of assessing the environmental conditions that their offspring will experience than the offspring themselves. In the dung beetle Onthophagus taurus, conditional male dimorphism is associated with alternative reproductive tactics: majors fight and guard females whereas minors sneak copulations. Furthermore, variation in dung beetle population density has different fitness consequences for each male morph, and theory predicts that higher population density might select for a higher frequency of minors and/or greater expenditure on weaponry in majors. Because adult dung beetles provide offspring with all the nutritional resources for their development, maternal effects strongly influence male phenotype. Results Here we tested whether female O. taurus are capable of perceiving population density, and responding by changing the phenotype of their offspring. We found that mothers who were reared with other conspecifics in their pre-mating period produced major offspring that had longer horns across a wider range of body sizes than the major offspring of females that were reared in isolation in their pre-mating period. Moreover, our results indicate that this maternal effect on male weaponry does not operate through the amount of dung provided by females to their offspring, but is rather transmitted through egg or brood mass composition. Finally, although theory predicts that females experiencing higher density might produce more minor males, we found no support for this, rather the best fitting models were equivocal as to whether fewer or the same proportions of minors were produced. Conclusions Our study describes a new type of maternal effect in dung beetles, which probably allows females to respond to population density adaptively, preparing at least their major offspring for the sexual competition they will face in the future. This new type of maternal effect in dung beetles represents a novel transgenerational response of alternative reproductive tactics to population density.
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Affiliation(s)
- Bruno A Buzatto
- Centre for Evolutionary Biology, School of Animal Biology (M092), The University of Western Australia, 35 Stirling Highway, Crawley 6009 WA, Australia.
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218
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Large-scale transcriptome analysis of retroelements in the migratory locust, Locusta migratoria. PLoS One 2012; 7:e40532. [PMID: 22792363 PMCID: PMC3391268 DOI: 10.1371/journal.pone.0040532] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Accepted: 06/10/2012] [Indexed: 11/23/2022] Open
Abstract
Background Retroelements can successfully colonize eukaryotic genome through RNA-mediated transposition, and are considered to be some of the major mediators of genome size. The migratory locust Locusta migratoria is an insect with a large genome size, and its genome is probably subject to the proliferation of retroelements. An analysis of deep-sequencing transcriptome data will elucidate the structure, diversity and expression characteristics of retroelements. Results We performed a de novo assembly from deep sequencing RNA-seq data and identified 105 retroelements in the locust transcriptome. Phylogenetic analysis of reverse transcriptase sequences revealed 1 copia, 1 BEL, 8 gypsy and 23 non-long terminal repeat (LTR) retroelements in the locust transcriptome. A novel approach was developed to identify full-length LTR retroelements. A total of 5 full-length LTR retroelements and 2 full-length non-LTR retroelements that contained complete structures for retrotransposition were identified. Structural analysis indicated that all these retroelements may have been activated or deprived of retrotransposition activities very recently. Expression profiling analysis revealed that the retroelements exhibited a unique expression pattern at the egg stage and showed differential expression profiles between the solitarious and gregarious phases at the fifth instar and adult stage. Conclusion We hereby present the first de novo transcriptome analysis of retroelements in a species whose genome is not available. This work contributes to a comprehensive understanding of the landscape of retroelements in the locust transcriptome. More importantly, the results reveal that non-LTR retroelements are abundant and diverse in the locust transcriptome.
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219
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Krug PJ, Gordon D, Romero MR. Seasonal Polyphenism in Larval Type: Rearing Environment Influences the Development Mode Expressed by Adults in the Sea Slug Alderia willowi. Integr Comp Biol 2012; 52:161-72. [DOI: 10.1093/icb/ics059] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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220
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Penick CA, Liebig J. Regulation of queen development through worker aggression in a predatory ant. Behav Ecol 2012. [DOI: 10.1093/beheco/ars062] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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