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Lorenz C, Suesdek L. The use of wing shape for characterising macroevolution in mosquitoes (Diptera: Culicidae). INFECTION GENETICS AND EVOLUTION 2019; 77:104052. [PMID: 31669430 DOI: 10.1016/j.meegid.2019.104052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 09/16/2019] [Accepted: 09/24/2019] [Indexed: 10/25/2022]
Abstract
The wing form of culicid mosquitoes shows considerable variation among groups: this phenomenon has been addressed by several studies through space-time analyses in mosquito populations, species, and genera. The observed variation results from a combination of two distinct factors: heredity and phenotypic plasticity. The first is usually related to wing shape, a complex character that may serve as a taxonomic marker in specific cases. We hypothesized that wing shape might be phylogenetically meaningful in Culicidae. In this study, we applied a geometric morphometrical approach based on 18 landmarks in 81 species of mosquitoes, representing 19 different genera, to investigate whether wing shape can help retrieve macroevolutionary patterns or identify any phylogenetic signals. We observed that wing shape differed considerably among groups, especially between Anophelinae and Culicinae subfamilies; thus, some wing shape elements may be synapomorphic. Comparisons among wing consensus after Procrustes superimposition revealed that landmark #1, located between the veins RS and R1, was the most variable. Sabethini tribe was distinguished from other taxa owing to a strong phylogenetic signal of its wings, whereas other culicids presented weaker signals and were not that distinguishable. Evolutionary forces such as natural selection, evolutionary limitation/constraint, or canalization mechanisms might drive the evolution of wing phenotype. These findings suggest that the wing undergoes evolution over long periods, but is not neutral enough to reconstruct the phylogenetic history of these insects. Gene-based studies should be performed to understand the driving forces in wing evolution.
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Affiliation(s)
- Camila Lorenz
- Departamento de Epidemiologia, Faculdade de Saúde Pública, Universidade de São Paulo, Av. Dr. Arnaldo, 715, São Paulo CEP 05509-300, Brazil; Biologia da Relação Patógeno-Hospedeiro- Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Prof. Lineu Prestes, 2415, São Paulo CEP 05508-000, Brazil.
| | - Lincoln Suesdek
- Instituto Butantan, Av. Vital Brazil 1500, Butantã, São Paulo, SP CEP 05503-900, Brazil; Instituto de Medicina Tropical, Universidade de São Paulo, Av. Dr. Enéas de Carvalho Aguiar 470, Jardim América, São Paulo, SP CEP 05403-000, Brazil
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Varón-González C, Navarro N. Epistasis regulates the developmental stability of the mouse craniofacial shape. Heredity (Edinb) 2019; 122:501-512. [PMID: 30209292 PMCID: PMC6461946 DOI: 10.1038/s41437-018-0140-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 07/13/2018] [Accepted: 07/14/2018] [Indexed: 12/19/2022] Open
Abstract
Fluctuating asymmetry is a classic concept linked to organismal development. It has traditionally been used as a measure of developmental instability, which is the inability of an organism to buffer environmental fluctuations during development. Developmental stability has a genetic component that influences the final phenotype of the organism and can lead to congenital disorders. According to alternative hypotheses, this genetic component might be either the result of additive genetic effects or a by-product of developmental gene networks. Here we present a genome-wide association study of the genetic architecture of fluctuating asymmetry of the skull shape in mice. Geometric morphometric methods were applied to quantify fluctuating asymmetry: we estimated fluctuating asymmetry as Mahalanobis distances to the mean asymmetry, correcting first for genetic directional asymmetry. We applied the marginal epistasis test to study epistasis among genomic regions. Results showed no evidence of additive effects but several interacting regions significantly associated with fluctuating asymmetry. Among the candidate genes overlapping these interacting regions we found an over-representation of genes involved in craniofacial development. A gene network is likely to be associated with skull developmental stability, and genes originally described as buffering genes (e.g., Hspa2) might occupy central positions within these networks, where regulatory elements may also play an important role. Our results constitute an important step in the exploration of the molecular roots of developmental stability and the first empirical evidence about its genetic architecture.
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Affiliation(s)
- Ceferino Varón-González
- Biogéosciences, UMR CNRS 6282, Université Bourgogne Franche-Comté, 6 Bd Gabriel, 21000, Dijon, France
| | - Nicolas Navarro
- Biogéosciences, UMR CNRS 6282, Université Bourgogne Franche-Comté, 6 Bd Gabriel, 21000, Dijon, France.
- EPHE, PSL University, 6 Bd Gabriel, 21000, Dijon, France.
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Analyzing Fluctuating Asymmetry with Geometric Morphometrics: Concepts, Methods, and Applications. Symmetry (Basel) 2015. [DOI: 10.3390/sym7020843] [Citation(s) in RCA: 213] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Dolgova O, Rego C, Calabria G, Balanyà J, Pascual M, Rezende EL, Santos M. Genetic constraints for thermal coadaptation in Drosophila subobscura. BMC Evol Biol 2010; 10:363. [PMID: 21108788 PMCID: PMC3003277 DOI: 10.1186/1471-2148-10-363] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Accepted: 11/25/2010] [Indexed: 11/23/2022] Open
Abstract
Background Behaviour has been traditionally viewed as a driver of subsequent evolution because behavioural adjustments expose organisms to novel environments, which may result in a correlated evolution on other traits. In Drosophila subobscura, thermal preference and heat tolerance are linked to chromosomal inversion polymorphisms that show parallel latitudinal clines worldwide, such that "cold-climate" ("warm-climate") chromosome arrangements collectively favour a coherent response to colder (warmer) settings as flies carrying them prefer colder (warmer) conditions and have lower (higher) knock out temperatures. Yet, it is not clear whether a genetic correlation between thermal preference and heat tolerance can partially underlie such response. Results We have analyzed the genetic basis of thermal preference and heat tolerance using isochromosomal lines in D. subobscura. Chromosome arrangements on the O chromosome were known to have a biometrical effect on thermal preference in a laboratory temperature gradient, and also harbour several genes involved in the heat shock response; in particular, the genes Hsp68 and Hsp70. Our results corroborate that arrangements on chromosome O affect adult thermal preference in a laboratory temperature gradient, with cold-climate Ost carriers displaying a lower thermal preference than their warm-climate O3+4 and O3+4+8 counterparts. However, these chromosome arrangements did not have any effect on adult heat tolerance and, hence, we putatively discard a genetic covariance between both traits arising from linkage disequilibrium between genes affecting thermal preference and candidate genes for heat shock resistance. Nonetheless, a possible association of juvenile thermal preference and heat resistance warrants further analysis. Conclusions Thermal preference and heat tolerance in the isochromosomal lines of D. subobscura appear to be genetically independent, which might potentially prevent a coherent response of behaviour and physiology (i.e., coadaptation) to thermal selection. If this pattern is general to all chromosomes, then any correlation between thermal preference and heat resistance across latitudinal gradients would likely reflect a pattern of correlated selection rather than genetic correlation.
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Affiliation(s)
- Olga Dolgova
- Departament de Genètica i de Microbiologia, Grup de Biologia Evolutiva (GBE), Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
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5
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Henry A, Thongsripong P, Fonseca-Gonzalez I, Jaramillo-Ocampo N, Dujardin JP. Wing shape of dengue vectors from around the world. INFECTION GENETICS AND EVOLUTION 2010; 10:207-14. [DOI: 10.1016/j.meegid.2009.12.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2009] [Revised: 11/16/2009] [Accepted: 12/05/2009] [Indexed: 10/20/2022]
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Deciphering morphology in Triatominae: the evolutionary signals. Acta Trop 2009; 110:101-11. [PMID: 19026978 DOI: 10.1016/j.actatropica.2008.09.026] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2008] [Revised: 09/30/2008] [Accepted: 09/30/2008] [Indexed: 11/20/2022]
Abstract
Many species of Triatominae show evidence for morphological plasticity. Frequent taxonomic questions arose from this variability leading to disputes about describing new subspecies, species or even genera. We suggest this phenotypic flexibility is primarily an intraspecific feature, but with potential for evolutionary changes. We present arguments for a selection regime leading to the separation of species having low developmental canalization into morphologically distinct ecotypes. We suggest that these ecotypes, or morphs, or forms, may have evolutionary importance even if gene flow still exists between them. Thus, although we consider the morphological plasticity of Triatominae as an intraspecific trait, we defend the idea that it might represent a common evolutionary route to new species. Speciation processes in Triatominae could result from disruptive selection regimes combined with weak developmental canalization. Added to this basic pattern, accidental events could hasten evolutionary change. We suggest the heterosis as one of them.
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Morphometrics applied to medical entomology. INFECTION GENETICS AND EVOLUTION 2008; 8:875-90. [DOI: 10.1016/j.meegid.2008.07.011] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2008] [Revised: 07/28/2008] [Accepted: 07/30/2008] [Indexed: 11/18/2022]
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Abstract
Chromosomal inversions suppress recombination in heterokaryotypes and may help to maintain positive epistatic interactions among groups of alleles at loci contained in the inversion. Here I evaluate the protective effect of inversions on recombination when different chromosomal segments, or even the whole chromosome O of Drosophila subobscura, can be effectively prevented from undergoing recombination in several naturally occurring heterokaryotypes. The fitness of flies made homozygous for recombinant chromosomes was generally lower when compared to their nonrecombinant counterparts, thus suggesting that segregating gene arrangements in this species hold together favorable combinations of alleles that interact epistatically.
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Mestres F, Serra L. The Va/Ba balanced lethal strain: thirty years of research in Drosophila subobscura (1977–2007). J ZOOL SYST EVOL RES 2008. [DOI: 10.1111/j.1439-0469.2008.00463.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Bubliy OA, Tcheslavskaia KS, Kulikov AM, Lazebny OE, Mitrofanov VG. Variation of wing shape in the Drosophila virilis species group (Diptera: Drosophilidae). J ZOOL SYST EVOL RES 2007. [DOI: 10.1111/j.1439-0469.2007.00437.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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SANTOS M. Evolution of total net fitness in thermal lines: Drosophila subobscura likes it ‘warm’. J Evol Biol 2007; 20:2361-70. [DOI: 10.1111/j.1420-9101.2007.01408.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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12
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Hatadani LM, Klaczko LB. Shape and size variation on the wing of Drosophila mediopunctata: influence of chromosome inversions and genotype-environment interaction. Genetica 2007; 133:335-42. [DOI: 10.1007/s10709-007-9217-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Accepted: 10/05/2007] [Indexed: 11/28/2022]
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Breuker CJ, Patterson JS, Klingenberg CP. A single basis for developmental buffering of Drosophila wing shape. PLoS One 2006; 1:e7. [PMID: 17183701 PMCID: PMC1762351 DOI: 10.1371/journal.pone.0000007] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Accepted: 09/07/2006] [Indexed: 11/19/2022] Open
Abstract
The nature of developmental buffering processes has been debated extensively, based on both theoretical reasoning and empirical studies. In particular, controversy has focused on the question of whether distinct processes are responsible for canalization, the buffering against environmental or genetic variation, and for developmental stability, the buffering against random variation intrinsic in developmental processes. Here, we address this question for the size and shape of Drosophila melanogaster wings in an experimental design with extensively replicated and fully controlled genotypes. The amounts of variation among individuals and of fluctuating asymmetry differ markedly among genotypes, demonstrating a clear genetic basis for size and shape variability. For wing shape, there is a high correlation between the amounts of variation among individuals and fluctuating asymmetry, which indicates a correspondence between the two types of buffering. Likewise, the multivariate patterns of shape variation among individuals and of fluctuating asymmetry show a close association. For wing size, however, the amounts of individual variation and fluctuating asymmetry are not correlated. There was a significant link between the amounts of variation between wing size and shape, more so for fluctuating asymmetry than for variation among individuals. Overall, these experiments indicate a considerable degree of shared control of individual variation and fluctuating asymmetry, although it appears to differ between traits.
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Santos M, Brites D, Laayouni H. Thermal evolution of pre-adult life history traits, geometric size and shape, and developmental stability in Drosophila subobscura. J Evol Biol 2006; 19:2006-21. [PMID: 17040398 DOI: 10.1111/j.1420-9101.2006.01139.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Replicated lines of Drosophila subobscura originating from a large outbred stock collected at the estimated Chilean epicentre (Puerto Montt) of the original New World invasion were allowed to evolve under controlled conditions of larval crowding for 3.5 years at three temperature levels (13, 18 and 22 degrees C). Several pre-adult life history traits (development time, survival and competitive ability), adult life history related traits (wing size, wing shape and wing-aspect ratio), and wing size and shape asymmetries were measured at the three temperatures. Cold-adapted (13 degrees C) populations evolved longer development times and showed lower survival at the highest developmental temperature. No divergence for wing size was detected following adaptation to temperature extremes (13 and 22 degrees C), in agreement with earlier observations, but wing shape changes were obvious as a result of both thermal adaptation and development at different temperatures. However, the evolutionary trends observed for the wing-aspect ratio were inconsistent with an adaptive hypothesis. There was some indication that wing shape asymmetry has evolutionarily increased in warm-adapted populations, which suggests that there is additive genetic variation for fluctuating asymmetry and that it can evolve under rapid environmental changes caused by thermal stress. Overall, our results cast strong doubts on the hypothesis that body size itself is the target of selection, and suggest that pre-adult life history traits are more closely related to thermal adaptation.
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Affiliation(s)
- M Santos
- Departament de Genètica i de Microbiologia, Grup de Biologia Evolutiva (GBE), Universitat Autònoma de Barcelona, Bellaterra (Barcelona), Spain.
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Rego C, Matos M, Santos M. SYMMETRY BREAKING IN INTERSPECIFIC DROSOPHILA HYBRIDS IS NOT DUE TO DEVELOPMENTAL NOISE. Evolution 2006. [DOI: 10.1111/j.0014-3820.2006.tb01153.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Seligmann H, Krishnan NM. Mitochondrial replication origin stability and propensity of adjacent tRNA genes to form putative replication origins increase developmental stability in Lizards. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2006; 306:433-49. [PMID: 16463378 DOI: 10.1002/jez.b.21095] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Secondary structure stability of mitochondrial origins of light-strand replication (OL) presumably reduces delayed formation of light-strand initiating replication forks on the heavy strand. Delayed replication initiation prolongs single strandedness of the heavy strand. More mutations accumulate during the prolonged time spent single stranded. Presumably, delayed replication initiation and excess mutations affect mitochondrial biochemical processes and ultimately morphological outcomes of development at the whole-organism level. This predicts that developmental stability increases with OL secondary structure stability and with formation of OL-like structures by the five tRNA genes flanking recognized OLs. Stable OLs and high percentages of OL-resembling secondary structures of adjacent tRNA genes (predicted by Mfold) correlate positively with developmental stability in three lizard families (Anguidae, Amphisbaenidae, and Polychrotidae). Accounting for effects of the regular OL, Sfold-predicted OL-like propensity of the entire tRNA gene cluster (not of individual genes) correlates with increased developmental stability in Anguidae, also across the entire free-energy range of Boltzmann's distribution of secondary structures. In the fossorial Amphisbaenidae, the OL-like structure-forming propensity of tRNA genes correlates positively with developmental stability for the distribution's sub-optimally stable regions, and negatively for its optimally stable regions, suggesting the thermoregulated functioning of OL vs. flanking tRNA genes as replication origins. Results for polychrotid tRNA genes are intermediate. Anguid tRNA genes possibly function in addition to the regular OL. Mitochondrial tRNA genes may thus frequently acquire and lose the alternative OL function, without sequence (gene) duplication and loss of their primary function.
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Affiliation(s)
- Hervé Seligmann
- Department of Evolution, Systematics and Ecology, The Hebrew University of Jerusalem, 91404, Israel.
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Rego C, Matos M, Santos M. SYMMETRY BREAKING IN INTERSPECIFIC DROSOPHILA HYBRIDS IS NOT DUE TO DEVELOPMENTAL NOISE. Evolution 2006. [DOI: 10.1554/05-540.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Klingenberg CP, Monteiro LR. Distances and Directions in Multidimensional Shape Spaces: Implications for Morphometric Applications. Syst Biol 2005; 54:678-88. [PMID: 16126663 DOI: 10.1080/10635150590947258] [Citation(s) in RCA: 243] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Affiliation(s)
- Christian Peter Klingenberg
- Faculty of Life Sciences, The University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, United Kingdom.
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Santos M, Iriarte PF, Céspedes W. Genetics and geometry of canalization and developmental stability in Drosophila subobscura. BMC Evol Biol 2005; 5:7. [PMID: 15663797 PMCID: PMC548280 DOI: 10.1186/1471-2148-5-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2004] [Accepted: 01/22/2005] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Many properties of organisms show great robustness against genetic and environmental perturbations. The terms canalization and developmental stability were originally proposed to describe the ability of an organism to resist perturbations and to produce a predictable target phenotype regardless of random developmental noise. However, the extent to which canalization and developmental stability are controlled by the same set of genes and share underlying regulatory mechanisms is largely unresolved. RESULTS We have analyzed the effects of clinical genetic variation (inversion polymorphism) on wing asymmetry by applying the methods of geometric morphometrics in the context of quantitative genetics using isochromosomal lines of Drosophila subobscura. For the analysis of overall size, developmental stability was positively correlated with levels of heterozygosity and development at the optimal temperature. For analyses of shape, the overall comparisons by matrix correlations indicate that inter- and intraindividual variation levels were poorly correlated, a result also supported when comparing the vectors describing patterns of variation of landmark position. The lack of similarity was basically due to the discrepancy between the genetic and environmental components of the interindividual variation. Finally, the analyses have also underscored the presence of genetic variation for directional asymmetry. CONCLUSIONS The results strongly support the hypothesis that environmental canalization and developmental stability share underlying regulatory mechanisms, but environmental and genetic canalization are not functionally the same. A likely explanation for this lack of association is that natural wing shape variation in Drosophila populations is loosely related to individual fitness.
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MESH Headings
- Analysis of Variance
- Animals
- Chromosomes
- Crosses, Genetic
- Drosophila/genetics
- Environment
- Evolution, Molecular
- Female
- Gene Expression Regulation, Developmental
- Genes, Insect
- Genetic Variation
- Genetics, Population
- Male
- Models, Biological
- Models, Genetic
- Models, Statistical
- Models, Theoretical
- Phenotype
- Polymorphism, Genetic
- Sex Factors
- Software
- Species Specificity
- Temperature
- Wings, Animal
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Affiliation(s)
- Mauro Santos
- Grup de Biologia Evolutiva (GBE), Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain
| | - Pedro Fernández Iriarte
- Grup de Biologia Evolutiva (GBE), Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain
- CICyTTP-CONICET, Matteri y España (3105) Diamante, Entre Ríos, Argentina
| | - Walkiria Céspedes
- Grup de Biologia Evolutiva (GBE), Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain
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Santos M, Céspedes W, Balanyà J, Trotta V, Calboli FCF, Fontdevila A, Serra L. Temperature-related genetic changes in laboratory populations of Drosophila subobscura: evidence against simple climatic-based explanations for latitudinal clines. Am Nat 2004; 165:258-73. [PMID: 15729655 DOI: 10.1086/427093] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2004] [Accepted: 10/18/2004] [Indexed: 11/03/2022]
Abstract
Parallel latitudinal clines to the long-standing ones in the original Palearctic populations have independently evolved at different rates for chromosomal polymorphism and body size in South and North American populations of Drosophila subobscura since colonization around 25 years ago. This strongly suggests that (micro) evolutionary changes are largely predictable, but the underlying mechanisms are unknown. The putative role of temperature per se was investigated by using three sets of populations at each of three temperatures (13 degrees , 18 degrees , and 22 degrees C) spanning much of the tolerable range for this species. We found a lower chromosomal diversity at the warmest temperature; a quick and consistent shift in gene arrangement frequencies in response to temperature; an evolutionary decrease in wing size, mediated by both cell area and cell number, at 18 degrees C; no relationship between wing size and those inversions involved in latitudinal clines; and a shortening of the basal length of longitudinal vein IV relative to its total length with increasing standard dose. The trends for chromosomal polymorphism and body size were generally inconsistent from simple climatic-based explanations of worldwide latitudinal patterns. The findings are discussed in the light of available information on D. subobscura and results from earlier thermal selection experiments with various Drosophila species.
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Affiliation(s)
- Mauro Santos
- Grup de Biologia Evolutiva, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
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