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De Araujo LI, Karsten M, Terblanche JS. Flight-reproduction trade-offs are weak in a field cage experiment across multiple Drosophila species. CURRENT RESEARCH IN INSECT SCIENCE 2023; 3:100060. [PMID: 37292492 PMCID: PMC10244903 DOI: 10.1016/j.cris.2023.100060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 05/18/2023] [Accepted: 05/23/2023] [Indexed: 06/10/2023]
Abstract
Flight-reproduction trade-offs, such that more mobile individuals sacrifice reproductive output (e.g., fecundity) or incur fitness costs, are well-studied in a handful of wing-dimorphic model systems. However, these trade-offs have not been systematically assessed across reproduction-related traits and taxa in wing monomorphic species despite having broad implications for the ecology and evolution of pterygote insect species. Here we therefore determined the prevalence, magnitude and direction of flight-reproduction trade-offs on several fitness-related traits in a semi-field setting by comparing disperser and resident flies from repeated releases of five wild-caught, laboratory-reared Drosophila species, and explicitly controlling for a suite of potential confounding effects (maternal effects, recent thermal history) and potential morphological covariates (wing-loading, body mass). We found almost no systematic differences in reproductive output (egg production), reproductive fitness (offspring survival), or longevity between flying (disperser) and resident flies in our replicated releases, even if adjusting for potential morphological variation. After correction for false discovery rates, none of the five species showed evidence of a significant fitness trade-off associated with increased flight (sustained, simulated voluntary field dispersal). Our results therefore suggest that flight-reproduction trade-offs are not as common as might have been expected when assessed systematically across species and under the relatively standardized conditions and field setting employed here, at least not in the genus Drosophila. The magnitude and direction of potential dispersal- or flight-induced trade-offs, and the conditions that promote them, clearly require closer scrutiny. We argue that flight or dispersal is either genuinely cheaper than expected, or the costs manifest differently than those assessed here. Lost opportunities (i.e., time spent on mate-finding, mating or foraging) or nutrient-poor conditions could promote fitness costs to dispersal in our study system and that could be explored in future.
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Ng'oma E, Williams-Simon PA, Rahman A, King EG. Diverse biological processes coordinate the transcriptional response to nutritional changes in a Drosophila melanogaster multiparent population. BMC Genomics 2020; 21:84. [PMID: 31992183 PMCID: PMC6988245 DOI: 10.1186/s12864-020-6467-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 01/08/2020] [Indexed: 12/19/2022] Open
Abstract
Background Environmental variation in the amount of resources available to populations challenge individuals to optimize the allocation of those resources to key fitness functions. This coordination of resource allocation relative to resource availability is commonly attributed to key nutrient sensing gene pathways in laboratory model organisms, chiefly the insulin/TOR signaling pathway. However, the genetic basis of diet-induced variation in gene expression is less clear. Results To describe the natural genetic variation underlying nutrient-dependent differences, we used an outbred panel derived from a multiparental population, the Drosophila Synthetic Population Resource. We analyzed RNA sequence data from multiple female tissue samples dissected from flies reared in three nutritional conditions: high sugar (HS), dietary restriction (DR), and control (C) diets. A large proportion of genes in the experiment (19.6% or 2471 genes) were significantly differentially expressed for the effect of diet, and 7.8% (978 genes) for the effect of the interaction between diet and tissue type (LRT, Padj. < 0.05). Interestingly, we observed similar patterns of gene expression relative to the C diet, in the DR and HS treated flies, a response likely reflecting diet component ratios. Hierarchical clustering identified 21 robust gene modules showing intra-modularly similar patterns of expression across diets, all of which were highly significant for diet or diet-tissue interaction effects (FDR Padj. < 0.05). Gene set enrichment analysis for different diet-tissue combinations revealed a diverse set of pathways and gene ontology (GO) terms (two-sample t-test, FDR < 0.05). GO analysis on individual co-expressed modules likewise showed a large number of terms encompassing many cellular and nuclear processes (Fisher exact test, Padj. < 0.01). Although a handful of genes in the IIS/TOR pathway including Ilp5, Rheb, and Sirt2 showed significant elevation in expression, many key genes such as InR, chico, most insulin peptide genes, and the nutrient-sensing pathways were not observed. Conclusions Our results suggest that a more diverse network of pathways and gene networks mediate the diet response in our population. These results have important implications for future studies focusing on diet responses in natural populations.
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Affiliation(s)
- E Ng'oma
- University of Missouri, 401 Tucker Hall, Columbia, MO, 65211, USA.
| | | | - A Rahman
- University of Missouri, 401 Tucker Hall, Columbia, MO, 65211, USA
| | - E G King
- University of Missouri, 401 Tucker Hall, Columbia, MO, 65211, USA
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Ng'oma E, Perinchery AM, King EG. How to get the most bang for your buck: the evolution and physiology of nutrition-dependent resource allocation strategies. Proc Biol Sci 2017; 284:20170445. [PMID: 28637856 PMCID: PMC5489724 DOI: 10.1098/rspb.2017.0445] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 05/23/2017] [Indexed: 12/31/2022] Open
Abstract
All organisms use resources to grow, survive and reproduce. The supply of these resources varies widely across landscapes and time, imposing ultimate constraints on the maximal trait values for allocation-related traits. In this review, we address three key questions fundamental to our understanding of the evolution of allocation strategies and their underlying mechanisms. First, we ask: how diverse are flexible resource allocation strategies among different organisms? We find there are many, varied, examples of flexible strategies that depend on nutrition. However, this diversity is often ignored in some of the best-known cases of resource allocation shifts, such as the commonly observed pattern of lifespan extension under nutrient limitation. A greater appreciation of the wide variety of flexible allocation strategies leads directly to our second major question: what conditions select for different plastic allocation strategies? Here, we highlight the need for additional models that explicitly consider the evolution of phenotypically plastic allocation strategies and empirical tests of the predictions of those models in natural populations. Finally, we consider the question: what are the underlying mechanisms determining resource allocation strategies? Although evolutionary biologists assume differential allocation of resources is a major factor limiting trait evolution, few proximate mechanisms are known that specifically support the model. We argue that an integrated framework can reconcile evolutionary models with proximate mechanisms that appear at first glance to be in conflict with these models. Overall, we encourage future studies to: (i) mimic ecological conditions in which those patterns evolve, and (ii) take advantage of the 'omic' opportunities to produce multi-level data and analytical models that effectively integrate across physiological and evolutionary theory.
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Affiliation(s)
- Enoch Ng'oma
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Anna M Perinchery
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Elizabeth G King
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
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McCue MD, Boardman L, Clusella-Trullas S, Kleynhans E, Terblanche JS. The speed and metabolic cost of digesting a blood meal depends on temperature in a major disease vector. ACTA ACUST UNITED AC 2016; 219:1893-902. [PMID: 27059066 DOI: 10.1242/jeb.138669] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 03/27/2016] [Indexed: 11/20/2022]
Abstract
The energetics of processing a meal is crucial for understanding energy budgets of animals in the wild. Given that digestion and its associated costs may be dependent on environmental conditions, it is necessary to obtain a better understanding of these costs under diverse conditions and identify resulting behavioural or physiological trade-offs. This study examines the speed and metabolic costs - in cumulative, absolute and relative energetic terms - of processing a bloodmeal for a major zoonotic disease vector, the tsetse fly Glossina brevipalpis, across a range of ecologically relevant temperatures (25, 30 and 35°C). Respirometry showed that flies used less energy digesting meals faster at higher temperatures but that their starvation tolerance was reduced, supporting the prediction that warmer temperatures are optimal for bloodmeal digestion while cooler temperatures should be preferred for unfed or post-absorptive flies. (13)C-Breath testing revealed that the flies oxidized dietary glucose and amino acids within the first couple of hours of feeding and overall oxidized more dietary nutrients at the cooler temperatures, supporting the premise that warmer digestion temperatures are preferred because they maximize speed and minimize costs. An independent test of these predictions using a thermal gradient confirmed that recently fed flies selected warmer temperatures and then selected cooler temperatures as they became post-absorptive, presumably to maximize starvation resistance. Collectively these results suggest there are at least two thermal optima in a given population at any time and flies switch dynamically between optima throughout feeding cycles.
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Affiliation(s)
- Marshall D McCue
- Department of Biological Sciences, St Mary's University, San Antonio, TX 78228, USA
| | - Leigh Boardman
- Centre for Invasion Biology, Department of Conservation Ecology and Entomology, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Susana Clusella-Trullas
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Elsje Kleynhans
- Centre for Invasion Biology, Department of Conservation Ecology and Entomology, Stellenbosch University, Stellenbosch 7600, South Africa
| | - John S Terblanche
- Centre for Invasion Biology, Department of Conservation Ecology and Entomology, Stellenbosch University, Stellenbosch 7600, South Africa
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Clark RM, Zera AJ, Behmer ST. Metabolic rate is canalized in the face of variable life history and nutritional environment. Funct Ecol 2015. [DOI: 10.1111/1365-2435.12574] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Rebecca M. Clark
- Department of Entomology Texas A&M University College Station TX 77843 USA
| | - Anthony J. Zera
- School of Biological Sciences University of Nebraska Lincoln NE 68588 USA
| | - Spencer T. Behmer
- Department of Entomology Texas A&M University College Station TX 77843 USA
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6
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McCue MD, Guzman RM, Passement CA, Davidowitz G. How and When Do Insects Rely on Endogenous Protein and Lipid Resources during Lethal Bouts of Starvation? A New Application for 13C-Breath testing. PLoS One 2015; 10:e0140053. [PMID: 26465334 PMCID: PMC4605643 DOI: 10.1371/journal.pone.0140053] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 09/21/2015] [Indexed: 01/16/2023] Open
Abstract
Most of our understanding about the physiology of fasting and starvation comes from studies of vertebrates; however, for ethical reasons, studies that monitor vertebrates through the lethal endpoint are scant. Insects are convenient models to characterize the comparative strategies used to cope with starvation because they have diverse life histories and have evolved under the omnipresent challenge of food limitation. Moreover, we can study the physiology of starvation through its natural endpoint. In this study we raised populations of five species of insects (adult grasshoppers, crickets, cockroaches, and larval beetles and moths) on diets labeled with either 13C-palmitic acid or 13C-leucine to isotopically enrich the lipids or the proteins in their bodies, respectively. The insects were allowed to become postabsorptive and then starved. We periodically measured the δ13C of the exhaled breath to characterize how each species adjusted their reliance on endogenous lipids and proteins as energy sources. We found that starving insects employ a wide range of strategies for regulating lipid and protein oxidation. All of the insects except for the beetle larvae were capable of sharply reducing reliance on protein oxidation; however, this protein sparing strategy was usually unsustainable during the entire starvation period. All insects increased their reliance on lipid oxidation, but while some species (grasshoppers, cockroaches, and beetle larvae) were still relying extensively on lipids at the time of death, other species (crickets and moth larvae) allowed rates of lipid oxidation to return to prestarvation levels. Although lipids and proteins are critical metabolic fuels for both vertebrates and insects, insects apparently exhibit a much wider range of strategies for rationing these limited resources during starvation.
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Affiliation(s)
- Marshall D. McCue
- St. Mary’s University, Department of Biological Sciences, San Antonio, Texas, United States of America
- * E-mail:
| | - R. Marena Guzman
- St. Mary’s University, Department of Biological Sciences, San Antonio, Texas, United States of America
| | - Celeste A. Passement
- St. Mary’s University, Department of Biological Sciences, San Antonio, Texas, United States of America
| | - Goggy Davidowitz
- University of Arizona, Department of Entomology, Tucson, Arizona, United States of America
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Clark RM, Zera AJ, Behmer ST. Nutritional physiology of life history trade-offs: how food protein-carbohydrate content influences life-history traits in the wing-polymorphic cricket Gryllus firmus. J Exp Biol 2014; 218:298-308. [DOI: 10.1242/jeb.112888] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Abstract
Although life-history trade-offs result from the differential acquisition and allocation of nutritional resources to competing physiological functions, many aspects of this topic remain poorly understood. Wing-polymorphic insects, which possess alternate morphs that trade off allocation to flight capability versus early reproduction, provide a good model system for exploring this topic. In this study we used the wing-polymorphic cricket Gryllus firmus to test how expression of the flight capability vs. reproduction trade-off was modified across a heterogeneous protein-carbohydrate nutritional landscape. Newly molted adult female crickets were given one of 13 diets with different concentrations and ratios of protein and digestible carbohydrate; for each cricket we measured consumption patterns, growth, and allocation to reproduction (ovary mass) vs. flight muscle maintenance (flight muscle mass and somatic lipid stores). Feeding responses in both morphs were influenced more by total macronutrient concentration than protein-carbohydrate ratio, except at high macronutrient concentration, where protein-carbohydrate balance was important. Mass gain tended to be greatest on protein-biased diets for both morphs, but was consistently lower across all diets for long-winged females. When long-winged females were fed high-carbohydrate foods they accumulated greater somatic lipid stores; on high-protein foods they accumulated greater somatic protein stores. Food protein-carbohydrate content also affected short-winged females (selected for early reproductive onset), which showed dramatic increases in ovary size, including ovarian stores of lipids and protein, on protein-biased foods. This is the first study to show how the concentration and ratio of dietary protein and carbohydrate affects consumption and allocation to key physiological features associated with the reproduction-dispersal life-history trade-off.
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Hu DB, Luo BQ, Li J, Han Y, Jiang TR, Liu J, Wu G, Hua HX, Xiong YF, Li JS. Genome-wide analysis of Nilaparvata lugens nymphal responses to high-density and low-quality rice hosts. INSECT SCIENCE 2013; 20:703-716. [PMID: 23956011 DOI: 10.1111/j.1744-7917.2012.01571.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/30/2012] [Indexed: 06/02/2023]
Abstract
The brown planthopper (BPH) Nilaparvata lugens is an economically important pest on rice plants. In this study, the higher population density and yellow-ripe stage of rice plants were used to construct adverse survival conditions (ASC) against BPH nymphs. Simultaneously, the low population density and tillering stage of rice plants were used to establish a suitable survival condition (SSC) as a control. Solexa/Illumina sequencing was used to identify genes of BPH nymphs responding to ASC. Significantly longer duration development of BPH nymphs and significantly lower brachypterous ratio of BPH adults were observed by ASC compared with SSC. A total of 2 544 differentially expressed genes (DEGs) were obtained and analyzed by BLASTx, Gene Ontology and KEGG Orthology. Gene ontology analysis revealed that the DEGs were mainly involved in categories of cell, cell part, cellular process, binding, catalytic, organelle and metabolic processes. 1 138 DEGs having enzyme commission numbers were assigned to different metabolic pathways. The largest clusters were neurodegenerative diseases (137, 12.0%), followed by carbohydrate metabolism (113, 9.9%), amino acid metabolism (94, 8.3%), nucleotide metabolism (76, 6.7%), energy metabolism (64, 5.6%), translation (60, 5.3%), lipid metabolism (58, 5.1%), and folding, sorting and degradation (52, 4.6%). Expressing profile of 11 DEGs during eight nymphal developmental stages of BPH were analyzed by quantitative real-time polymerase chain reaction. The 11 genes exhibited differential expression between ASC and SSC during at least one developmental stage. The DEGs identified in this study provide molecular proof of how BPH reconfigures its gene expression profile to adapt to overcrowding and low-quality hosts.
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Affiliation(s)
- Ding-Bang Hu
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070
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9
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VAYSSADE CHLOÉ, MARTEL VÉRONIQUE, MOIROUX JOFFREY, FAUVERGUE XAVIER, VAN ALPHEN JACQUESJM, VAN BAAREN JOAN. The response of life-history traits to a new species in the community: a story of Drosophila parasitoids from the Rhône and Saône valleys. Biol J Linn Soc Lond 2012. [DOI: 10.1111/j.1095-8312.2012.01918.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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10
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Iserbyt A, Van Gossum H, Stoks R. Biogeographical survey identifies consistent alternative physiological optima and a minor role for environmental drivers in maintaining a polymorphism. PLoS One 2012; 7:e32648. [PMID: 22384278 PMCID: PMC3287987 DOI: 10.1371/journal.pone.0032648] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Accepted: 01/28/2012] [Indexed: 11/19/2022] Open
Abstract
The contribution of adaptive mechanisms in maintaining genetic polymorphisms is still debated in many systems. To understand the contribution of selective factors in maintaining polymorphism, we investigated large-scale (>1000 km) geographic variation in morph frequencies and fitness-related physiological traits in the damselfly Nehalennia irene. As fitness-related physiological traits, we investigated investment in immune function (phenoloxidase activity), energy storage and fecundity (abdomen protein and lipid content), and flight muscles (thorax protein content). In the first part of the study, our aim was to identify selective agents maintaining the large-scale spatial variation in morph frequencies. Morph frequencies varied considerably among populations, but, in contrast to expectation, in a geographically unstructured way. Furthermore, frequencies co-varied only weakly with the numerous investigated ecological parameters. This suggests that spatial frequency patterns are driven by stochastic processes, or alternatively, are consequence of highly variable and currently unidentified ecological conditions. In line with this, the investigated ecological parameters did not affect the fitness-related physiological traits differently in both morphs. In the second part of the study, we aimed at identifying trade-offs between fitness-related physiological traits that may contribute to the local maintenance of both colour morphs by defining alternative phenotypic optima, and test the spatial consistency of such trade-off patterns. The female morph with higher levels of phenoloxidase activity had a lower thorax protein content, and vice versa, suggesting a trade-off between investments in immune function and in flight muscles. This physiological trade-off was consistent across the geographical scale studied and supports widespread correlational selection, possibly driven by male harassment, favouring alternative trait combinations in both female morphs.
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Affiliation(s)
- Arne Iserbyt
- Evolutionary Ecology Group, Antwerp University, Antwerp, Belgium.
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11
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Judd ET, Wessels FJ, Drewry MD, Grove M, Wright K, Hahn DA, Hatle JD. Ovariectomy in grasshoppers increases somatic storage, but proportional allocation of ingested nutrients to somatic tissues is unchanged. Aging Cell 2011; 10:972-9. [PMID: 21834847 PMCID: PMC3215815 DOI: 10.1111/j.1474-9726.2011.00737.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Reduced reproduction increases storage and extends lifespan in several animal species. The disposable soma hypothesis suggests this life extension occurs by shifting allocation of ingested nutrients from reproduction to the soma. A great deal of circumstantial evidence supports this hypothesis, but no direct tracking of nutrients has been performed in animals that are long-lived because of direct reduction in reproduction. Here, we use the stable isotopes to track carbon and nitrogen from ingestion to somatic organs in long-lived, ovariectomized grasshoppers. Three estimates of somatic storage (viz., quantity of hemolymph storage proteins, amount of femur muscle carbohydrates, and size of the fat body) all doubled upon ovariectomy. In stark contrast, ovariectomy did not increase the proportion of these tissues that were made from recently ingested foods. In other words, the physiology underlying relative allocation to these somatic tissues was not affected by ovariectomy. Thus, at the level of whole tissue storage, these results are consistent with a trade-off between reproduction and longevity. In contrast, our stable isotope data are inconsistent with the prediction that enhanced storage in ovariectomized females results from a physiological shift in allocation of ingested nutrients.
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Affiliation(s)
- Evan T Judd
- Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, FL 32224, USA
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Bonte D, Van Dyck H, Bullock JM, Coulon A, Delgado M, Gibbs M, Lehouck V, Matthysen E, Mustin K, Saastamoinen M, Schtickzelle N, Stevens VM, Vandewoestijne S, Baguette M, Barton K, Benton TG, Chaput-Bardy A, Clobert J, Dytham C, Hovestadt T, Meier CM, Palmer SCF, Turlure C, Travis JMJ. Costs of dispersal. Biol Rev Camb Philos Soc 2011; 87:290-312. [DOI: 10.1111/j.1469-185x.2011.00201.x] [Citation(s) in RCA: 840] [Impact Index Per Article: 64.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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13
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King EG, Roff DA, Fairbairn DJ. The evolutionary genetics of acquisition and allocation in the wing dimorphic cricket, Gryllus firmus. Evolution 2011; 65:2273-85. [PMID: 21790574 DOI: 10.1111/j.1558-5646.2011.01296.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The evolutionary trajectories of trade-offs are ultimately governed by the evolution of the underlying physiological processes of the acquisition and subsequent allocation of resources. In this study, we focused directly on acquisition and allocation as traits and estimated their genetic architecture in the trade-off between flight capability and reproduction in the cricket, Gryllus firmus. To determine the evolutionary genetics of acquisition and allocation both within and between resource environments, we performed a large-scale quantitative genetic breeding experiment in which families were split over several resource levels. Our findings were fourfold: (1) there was substantial genetic variance in acquisition and allocation, (2) contrary to the assumption of independence between acquisition and allocation, there was a significant genetic correlation between them, (3) the genetic covariance between acquisition and allocation was significantly different in the different food environments, (4) the trade-off, as measured by the genetic correlation between flight muscle mass and ovary mass, was only significant in the food restriction environments. However, when measured directly as the genetic correlation between reproductive allocation and flight allocation, we found a consistent strong negative genetic correlation, demonstrating that when allocation is measured independently of acquisition we find evidence for the trade-off.
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Affiliation(s)
- Elizabeth G King
- Department of Biology and Graduate Program in Evolution, Ecology and Organismal Biology, University of California, Riverside, California 92521, USA.
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14
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Guerra PA. Evaluating the life-history trade-off between dispersal capability and reproduction in wing dimorphic insects: a meta-analysis. Biol Rev Camb Philos Soc 2011; 86:813-35. [PMID: 21199288 DOI: 10.1111/j.1469-185x.2010.00172.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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15
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King EG, Roff DA. Modeling the evolution of phenotypic plasticity in resource allocation in wing-dimorphic insects. Am Nat 2010; 175:702-16. [PMID: 20397908 DOI: 10.1086/652434] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
In nature, resource availability varies spatially and temporally both within and across generations, leading to variation in the amount of energy available to individuals. The optimal allocation strategy can change, depending on the amount of resources available to allocate to life-history functions. If so, selection should favor the evolution of allocation strategies that can respond to variation in environmental resource levels. We address this issue by using two quantitative genetic simulation models in a model system for studying trade-offs, wing-dimorphic insects. Wing dimorphic insects typically exhibit a trade-off in the allocation of resources between migratory ability and reproduction. In our models, we focus on allocation as a genetic trait and model the evolution of phenotypic plasticity in this trait in response to spatiotemporal variation in resource availability. We show that the evolved allocation strategy depends on the predictability of resource levels across time. Specifically, selection favors higher investment in flight under poor conditions in predictable environments and lower investment in unpredictable environments.
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Affiliation(s)
- Elizabeth G King
- Department of Biology, University of California, Riverside, California 92521, USA.
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Reisig DD, Godfrey LD, Marcum DB. Plant quality and conspecific density effects on Anaphothrips obscurus (Thysanoptera: Thripidae) wing diphenism and population ecology. ENVIRONMENTAL ENTOMOLOGY 2010; 39:685-694. [PMID: 20388303 DOI: 10.1603/en09332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Factors that influence thysanopteran wing diphenism are not well known. In these studies, the impact of food quality, mediated through nitrogen addition, and conspecific density was explored on the wing diphenism of an herbivorous thrips species (Anaphothrips obscurus Müller) (Thysanoptera: Thripidae). In the first study, nitrogen was added to timothy grass (Phleum pretense L.) (Poales: Poaceae) transplants, and naturally occurring thrips populations were caged on the plants. Thrips abundance and foliar nutrients were assessed every 2 wk. A separate factorial experiment in growth chambers explored the impact of both plant nitrogen addition and thrips abundance on wing diphenism. Thrips density was manipulated by adding either 3 or 40 thrips to potted and caged timothy. Thrips abundance and foliar nutrients were measured 58 d after treatment placement. Plant quality directly affected thrips wing diphenism independent of thrips density in both experiments. Near the end of the field cage experiment, density may have indirectly impacted wing diphenism. In both experiments, plant quality and thrips density interacted to affect thrips population abundance. Plant quality alone can affect thrips wing diphenism, but it remains unclear whether density alone can affect thrips wing diphenism. This is a unique and understudied system that will be useful to examine generalized theories on the negative interaction between reproduction and dispersal.
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Affiliation(s)
- Dominic D Reisig
- Department of Entomology, North Carolina State University, Vernon G James Research and Extension Center, 207 Research Station Rd, Plymouth, NC 27962, USA.
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17
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Oliver RH, Albury ANJ, Mousseau TA. Programmed cell death in flight muscle histolysis of the house cricket. JOURNAL OF INSECT PHYSIOLOGY 2007; 53:30-9. [PMID: 17118399 PMCID: PMC1936969 DOI: 10.1016/j.jinsphys.2006.09.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2006] [Revised: 09/21/2006] [Accepted: 09/29/2006] [Indexed: 05/12/2023]
Abstract
We have characterized the process of flight muscle histolysis in the female house cricket, Acheta domesticus, through analysis of alterations of tissue wet weight, total protein content, and percent shortening of the dorsal longitudinal flight muscles (DLMs). Our objectives were to (1) define the normal course of histolysis in the cricket, (2) analyze the effects of juvenile hormone (JH) removal and replacement, (3) determine the effects of cycloheximide treatment, and (4) examine patterns of protein expression during histolysis. Our results suggest that flight muscle histolysis in the house cricket is an example of an active, developmentally regulated cell death program induced by an endocrine signal. Initial declines of total protein in DLMs indicated the JH signal that induced histolysis occurred by Day 2 and that histolysis was essentially complete by Day 3. Significant reductions in tissue weight and percent muscle shortening were observed in DLMs from Day 3 crickets. Cervical ligation of Day 1 crickets prevented histolysis but this inhibition could be reversed by continual topical treatments with methoprene (an active JH analog) although ligation of Day 2 crickets did not prevent histolysis. A requirement for active protein expression was demonstrated by analysis of synthesis block by cycloheximide and short-term incorporation of (35)S-methionine. Treatment with cycloheximide prevented histolysis. Autofluorographic imaging of DLM proteins separated by electrophoresis revealed apparent coordinated regulation of protein expression.
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Affiliation(s)
- Rush H Oliver
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA.
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