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  • 101.
    Sirkiä, Päivi M
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    McFarlane, S. Eryn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Jones, William
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Wheatcroft, David
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Ålund, Murielle
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Rybinski, Jakub
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Qvarnström, Anna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Climate-driven build-up of temporal isolation within a recently formed avian hybrid zone.2018Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 72, nr 2, s. 363-374Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Divergence in the onset of reproduction can act as an important source of reproductive isolation (i.e., allochronic isolation) between co-occurring young species, but evidence for the evolutionary processes leading to such divergence is often indirect. While advancing spring seasons strongly affect the onset of reproduction in many taxa, it remains largely unexplored whether contemporary spring advancement directly affects allochronic isolation between young species. We examined how increasing spring temperatures affected onset of reproduction and thereby hybridization between pied and collared flycatchers (Ficedula spp.) across habitat types in a young secondary contact zone. We found that both species have advanced their timing of breeding in 14 years. However, selection on pied flycatchers to breed earlier was weaker, resulting in a slower response to advancing springs compared to collared flycatchers and thereby build-up of allochronic isolation between the species. We argue that a preadaptation to a broader niche use (diet) of pied flycatchers explains the slower response to raising spring temperature, but that reduced risk to hybridize may contribute to further divergence in the onset of breeding in the future. Our results show that minor differences in the response to environmental change of co-occurring closely related species can quickly cause allochronic isolation.

  • 102.
    Sletvold, Nina
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Mousset, Mathilde
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Hagenblad, Jenny
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Hansson, Bengt
    Ågren, Jon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Strong Inbreeding Depression In Two Scandinavian Populations Of The Self-Incompatible Perennial Herb Arabidopsis Lyrata2013Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 67, nr 10, s. 2876-2888Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Inbreeding depression is a key factor influencing mating system evolution in plants, but current understanding of its relationship with selfing rate is limited by a sampling bias with few estimates for self-incompatible species. We quantified inbreeding depression () over two growing seasons in two populations of the self-incompatible perennial herb Arabidopsis lyrata ssp. petraea in Scandinavia. Inbreeding depression was strong and of similar magnitude in both populations. Inbreeding depression for overall fitness across two seasons (the product of number of seeds, offspring viability, and offspring biomass) was 81% and 78% in the two populations. Chlorophyll deficiency accounted for 81% of seedling mortality in the selfing treatment, and was not observed among offspring resulting from outcrossing. The strong reduction in both early viability and late quantitative traits suggests that inbreeding depression is due to deleterious alleles of both large and small effect, and that both populations experience strong selection against the loss of self-incompatibility. A review of available estimates suggested that inbreeding depression tends to be stronger in self-incompatible than in self-compatible highly outcrossing species, implying that undersampling of self-incompatible taxa may bias estimates of the relationship between mating system and inbreeding depression.

  • 103.
    Sletvold, Nina
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Trunschke, Judith
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Smit, Mart
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Verbeek, Jeffrey
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Ågren, Jon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Strong pollinator-mediated selection for increased flower brightness and contrast in a deceptive orchid2016Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 70, nr 3, s. 716-724Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Contrasting flower color patterns that putatively attract or direct pollinators toward a reward are common among angiosperms. In the deceptive orchid Anacamptis morio, the lower petal, which makes up most of the floral display, has a light central patch with dark markings. Within populations, there is pronounced variation in petal brightness, patch size, amount of dark markings, and contrast between patch and petal margin. We tested whether pollinators mediate selection on these color traits and on morphology (plant height, number of flowers, corolla size, spur length), and whether selection is consistent with facilitated or negative frequency-dependent pollination. Pollinators mediated strong selection for increased petal brightness (Delta beta(poll) = 0.42) and contrast (Delta beta(poll) = 0.51). Pollinators also tended to mediate stabilizing selection on brightness (Delta gamma(poll) = -0.27, n.s.) favoring the most common phenotype in the population. Selection for reduced petal brightness among hand-pollinated plants indicated a fitness cost associated with brightness. The results demonstrate that flower color traits influence pollination success and seed production in A. morio, indicating that they affect attractiveness to pollinators, efficiency of pollen transfer, or both. The documented selection is consistent with facilitated pollination and selection for color convergence toward cooccurring rewarding species.

  • 104.
    Sletvold, Nina
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Ågren, Jon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    There is More to Pollinator-Mediated Selection than Pollen Limitation2014Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 68, nr 7, s. 1907-1918Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Spatial variation in pollinator-mediated selection (Delta beta(poll)) is a major driver of floral diversification, but we lack a quantitative understanding of its link to pollen limitation (PL) and net selection on floral traits. For 2-5 years, we quantified Delta beta(poll) on floral traits in two populations each of two orchid species differing in PL. In both species, spatiotemporal variation in Delta beta(poll) explained much of the variation in net selection. Selection was consistently stronger and the proportion that was pollinator-mediated was higher in the severely pollen-limited deceptive species than in the rewarding species. Within species, variation in PL could not explain variation in Delta beta(poll) for any trait, indicating that factors influencing the functional relationship between trait variation and pollination success govern a major part of the observed variation in Delta beta(poll). Separating the effects of variation in mean interaction intensity and in the functional significance of traits will be necessary to understand spatiotemporal variation in selection exerted by the biotic environment.

  • 105.
    Slotte, Tanja
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Hazzouri, Khaled M.
    Stern, David
    Andolfatto, Peter
    Wright, Stephen I.
    Genetic architecture and adaptive significance of the selfing syndrome in Capsella2012Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 66, nr 5, s. 1360-1374Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The transition from outcrossing to predominant self-fertilization is one of the most common evolutionary transitions in flowering plants. This shift is often accompanied by a suite of changes in floral and reproductive characters termed the selfing syndrome. Here, we characterize the genetic architecture and evolutionary forces underlying evolution of the selfing syndrome in Capsella rubella following its recent divergence from the outcrossing ancestor C. grandiflora. We conduct genotyping by multiplexed shotgun sequencing and map floral and reproductive traits in a large (N= 550) F2 population. Our results suggest that in contrast to previous studies of the selfing syndrome, changes at a few loci, some with major effects, have shaped the evolution of the selfing syndrome in Capsella. The directionality of QTL effects, as well as population genetic patterns of polymorphism and divergence at 318 loci, is consistent with a history of directional selection on the selfing syndrome. Our study is an important step toward characterizing the genetic basis and evolutionary forces underlying the evolution of the selfing syndrome in a genetically accessible model system.

  • 106. South, Sandra H.
    et al.
    Arnqvist, Goran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Servedio, Maria R.
    FEMALE PREFERENCE FOR MALE COURTSHIP EFFORT CAN DRIVE THE EVOLUTION OF MALE MATE CHOICE2012Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 66, nr 12, s. 3722-3735Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The evolution of male mate choice is constrained by costs of choice in species with a male-biased operational sex ratio (OSR). Previous theoretical studies have shown that significant benefits of male choice are required, for example, by mating with more fecund females, in order for these costs to be offset and a male preference to spread. In a series of population genetic models we show the novel effect that male mating preference, expressed as a bias in courtship, can spread when females prefer, and thus are more likely to mate with, males who court more. We explore two female preference functions for levels of male courtship, one representing a threshold and the other a weighted female preference. The basic finding generally holds for both preference functions. However, the preference function greatly affects the spread of a male preference allele after the addition of competing males who can court more in total. Our results thus stress that a thorough understanding of the response of females to male courtship is a critical component to understanding male preference evolution in polygynous species.

  • 107.
    South, Sandra H.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    House, Clarissa M.
    Moore, Allen J.
    Simpson, Stephen J.
    Hunt, John
    Male Cockroaches Prefer a High Carbohydrate Diet that Makes them More Attractive to Females: implications for the study of condition dependence2011Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 65, nr 6, s. 1594-1606Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sexual selection is a major force driving the evolution of elaborate male sexual traits. Handicap models of sexual selection predict that male sexual traits should covary positively with condition, making them reliable indicators of male quality. However, most studies have either manipulated condition through varying diet quantity and/or caloric content without knowledge of specific nutrient effects or have correlated proxies of condition with sexual trait expression. We used nutritional geometry to quantify protein and carbohydrate intake by male cockroaches, Nauphoeta cinerea, and related this to sex pheromone expression, attractiveness, and dominance status. We found that carbohydrate, but not protein, intake is related to male sex pheromone expression and attractiveness but not dominance status. Additionally, we related two condition proxies (weight gain and lipid reserves) to protein and carbohydrate acquisition. Weight gain increased with the intake of both nutrients, whereas lipid reserves only increased with carbohydrate intake. Importantly, lipid accumulation was not as responsive to carbohydrate intake as attractiveness and thus was a less-accurate condition proxy. Moreover, males preferentially consumed high carbohydrate diets with little regard for protein content suggesting that they actively increase their carbohydrate intake thereby maximizing their reproductive fitness by being attractive.

  • 108.
    Spagopoulou, Foteini
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Blom, Mozes P. K.
    Naturhistoriska Riksmuseet, Department of Bioinformatic and Genetics, Stockholm, Sweden.
    Digest: Life history evolution in Darwin's dream ponds2018Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 72, nr 5, s. 1186-1188Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Can variation in sex‐specific parental investment lead to sexual dimorphism in immune response? Keller et al. (2018) measured immune cell parameters, expression of candidate genes and composition of buccal microbiota in mouthbrooding cichlid species from Lake Tanganyika that show either maternal or biparental care. They found that maternal mouthbrooding species have increased sexual dimorphism in immune parameters, while biparental mouthbrooders exhibit an upregulated adaptive immune response, suggesting resource allocation shifts between parental investment and the immune system.

  • 109. Staubach, Fabian
    et al.
    Teschke, Meike
    Voolstra, Christian R.
    Wolf, Jochen B. W.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Tautz, Diethard
    A test of the neutral model of expression change in natural populations of house mouse subspecies2010Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 64, nr 2, s. 549-560Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Changes in expression of genes are thought to contribute significantly to evolutionary divergence. To study the relative role of selection and neutrality in shaping expression changes, we analyzed 24 genes in three different tissues of the house mouse (Mus musculus). Samples from two natural populations of the subspecies M. m. domesticus and M. m. musculus were investigated using quantitative PCR assays and sequencing of the upstream region. We have developed an approach to quantify expression polymorphism within such populations and to disentangle technical from biological variation in the data. We found a correlation between expression polymorphism within populations and divergence between populations. Furthermore, we found a correlation between expression polymorphism and sequence polymorphism of the respective genes. These data are most easily interpreted within a framework of a predominantly neutral model of gene expression change, where only a fraction of the changes may have been driven by positive selection. Although most genes investigated were expressed in all three tissues analyzed, significant changes of expression levels occurred predominantly in a single tissue only. This adds to the notion that enhancer-specific effects or transregulatory effects can modulate the evolution of gene expression in a tissue-specific way.

  • 110. Stenoien, Hans K.
    et al.
    Shaw, A. Jonathan
    Shaw, Blanka
    Hassel, Kristian
    Gunnarsson, Urban
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    North american origin and recent European establishments of the amphi-atlantic peat moss sphagnum angermanicum2011Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 65, nr 4, s. 1181-1194Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Genetic and morphological similarity between populations separated by large distances may be caused by frequent long-distance dispersal or retained ancestral polymorphism. The frequent lack of differentiation between disjunct conspecific moss populations on different continents has traditionally been explained by the latter model, and has been cited as evidence that many or most moss species are extremely ancient and slowly diverging. We have studied intercontinental differentiation in the amphi-Atlantic peat moss Sphagnum angermanicum using 23 microsatellite markers. Two major genetic clusters are found, both of which occur throughout the distributional range. Patterns of genetic structuring and overall migration patterns suggest that the species probably originated in North America, and seems to have been established twice in Northern Europe during the past 40,000 years. We conclude that similarity between S. angermanicum populations on different continents is not the result of ancient vicariance and subsequent stasis. Rather, the observed pattern can be explained by multiple long-distance dispersal over limited evolutionary time. The genetic similarity can also partly be explained by incomplete lineage sorting, but this appears to be caused by the short time since separation. Our study adds to a growing body of evidence suggesting that Sphagnum, constituting a significant part of northern hemisphere biodiversity, may be more evolutionary dynamic than previously assumed.

  • 111.
    Stojkovic, Biljana
    et al.
    Univ Belgrade, Inst Zool, Fac Biol, Studentski Trg 16, Belgrade 11000, Serbia.;Univ Belgrade, Inst Biol Res Sinisa Stankovic, Dept Evolutionary Biol, Despota Stefana Blvd 142, Belgrade 11060, Serbia..
    Sayadi, Ahmed
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Dordevic, Mirko
    Univ Belgrade, Inst Biol Res Sinisa Stankovic, Dept Evolutionary Biol, Despota Stefana Blvd 142, Belgrade 11060, Serbia..
    Jovic, Jelena
    Inst Plant Protect & Environm, Dept Plant Pests, Banatska 33, Zemun 11080, Serbia..
    Savkovic, Uros
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Arnqvist, Göran
    Univ Belgrade, Inst Biol Res Sinisa Stankovic, Dept Evolutionary Biol, Despota Stefana Blvd 142, Belgrade 11060, Serbia..
    Divergent evolution of life span associated with mitochondrial DNA evolution2017Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 71, nr 1, s. 160-166Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mitochondria play a key role in ageing. The pursuit of genes that regulate variation in life span and ageing have shown that several nuclear-encoded mitochondrial genes are important. However, the role of mitochondrial encoded genes (mtDNA) is more controversial and our appreciation of the role of mtDNA for the evolution of life span is limited. We use replicated lines of seed beetles that have been artificially selected for long or short life for >190 generations, now showing dramatic phenotypic differences, to test for a possible role of mtDNA in the divergent evolution of ageing and life span. We show that these divergent selection regimes led to the evolution of significantly different mtDNA haplotype frequencies. Selection for a long life and late reproduction generated positive selection for one specific haplotype, which was fixed in most such lines. In contrast, selection for reproduction early in life led to both positive selection as well as negative frequency-dependent selection on two different haplotypes, which were both present in all such lines. Our findings suggest that the evolution of life span was in part mediated by mtDNA, providing support for the emerging general tenet that adaptive evolution of life-history syndromes may involve mtDNA.

  • 112.
    Svanbäck, Richard
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Eklov, Peter
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Catch me if you can: Predation affetcs divergence in a polyphenic species2011Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 65, nr 12, s. 3515-3526Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Predation is a major driving force in evolution. Predation has been shown to select for size, morphology, and camouflage. Many animals use camouflage to reduce predation risk. In some cases, individuals can adjust their pigmentation, enabling them a higher survival in a heterogeneous environment. Here, we show that the difference in pigmentation between juvenile perch individuals (Perca fluvuiatilis) occupying different environments (open water and vegetated habitats of lakes) is likely a consequence of predator selection. Lightly pigmented individuals have a higher chance of survival in open water whereas darker pigmented individuals survive better in vegetation. As a response to predators, individuals forced into the vegetation by predators developed darker skin whereas the skin of individuals forced into open water became lighter. In a common garden experiment, in the absence of predation, we found that pigmentation in juvenile perch is only due to plasticity and not to genetic variation. However, contrary to predictions, individuals raised in open water developed darker skin compared to individuals raised in vegetation. This may be a response to UV-stress. Overall, our results suggest that predation can be a strong selective agent on pigmentation differences among conspecifics occupying different habitats.

  • 113. Svardal, Hannes
    et al.
    Rüffler, Claus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Doebeli, Michael
    Organismal Complexity and the Potential for Evolutionary Diversification2014Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 68, nr 11, s. 3248-3259Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present two theoretical approaches to investigate whether organismal complexity, defined as the number of quantitative traits determining fitness, and the potential for adaptive diversification are correlated. The first approach is independent of any specific ecological model and based on curvature properties of the fitness landscape as a function of the dimension of the trait space. This approach indeed suggests a positive correlation between complexity and diversity. An assumption made in this first approach is that the potential for any pair of traits to interact in their effect on fitness is independent of the dimension of the trait space. In the second approach, we circumvent making this assumption by analyzing the evolutionary dynamics in an explicit consumer-resource model in which the shape of the fitness landscape emerges from the underlying mechanistic ecological model. In this model, consumers are characterized by several quantitative traits and feed on a multidimensional resource distribution. The consumer's feeding efficiency on the resource is determined by the match between consumer phenotype and resource item. This analysis supports a positive correlation between the complexity of the evolving consumer species and its potential to diversify with the additional insight that also increasing resource complexity facilitates diversification.

  • 114.
    Toräng, Per
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution. Univ Skovde, Sch Biosci, SE-54128 Skovde, Sweden..
    Vikström, Linus
    Uppsala Univ, Dept Plant Ecol & Evolut, Evolutionary Biol Ctr, Norbyvagen 18D, SE-75236 Uppsala, Sweden..
    Wunder, Jörg
    Max Planck Inst Plant Breeding Res, Dept Plant Dev Biol, Carl von Linne Weg 10, D-50829 Cologne, Germany..
    Wötzel, Stefan
    Max Planck Inst Plant Breeding Res, Dept Plant Dev Biol, Carl von Linne Weg 10, D-50829 Cologne, Germany..
    Coupland, George
    Max Planck Inst Plant Breeding Res, Dept Plant Dev Biol, Carl von Linne Weg 10, D-50829 Cologne, Germany..
    Ågren, Jon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Evolution of the selfing syndrome: Anther orientation and herkogamy together determine reproductive assurance in a self-compatible plant2017Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 71, nr 9, s. 2206-2218Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Capacity for autonomous self-fertilization provides reproductive assurance, has evolved repeatedly in the plant kingdom, and typically involves several changes in flower morphology and development (the selfing syndrome). Yet, the relative importance of different traits and trait combinations for efficient selfing and reproductive success in pollinator-poor environments is poorly known. In a series of experiments, we tested the importance of anther-stigma distance and the less studied trait anther orientation for efficiency of selfing in the perennial herb Arabis alpina. Variation in flower morphology among eight self-compatible European populations was correlated with efficiency of self-pollination and with pollen limitation in a common-garden experiment. To examine whether anther-stigma distance and anther orientation are subject to directional and/or correlational selection, and whether this is because these traits affect pollination success, we planted a segregating F2 population at two native field sites. Selection strongly favored a combination of introrse anthers and reduced anther-stigma distance at a site where pollinator activity was low, and supplemental hand-pollination demonstrated that this was largely because of their effect on securing self-pollination. The results suggest that concurrent shifts in more than one trait can be crucial for the evolution of efficient self-pollination and reproductive assurance in pollinator-poor habitats.

  • 115.
    Tsuboi, Masahito
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Husby, Arild
    Kotrschal, Alexander
    Hayward, Alexander
    Buechel, Severine D.
    Zidar, Josefina
    Lovlie, Hanne
    Kolm, Niclas
    Comparative support for the expensive tissue hypothesis: Big brains are correlated with smaller gut and greater parental investment in Lake Tanganyika cichlids2015Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 69, nr 1, s. 190-200Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The brain is one of the most energetically expensive organs in the vertebrate body. Consequently, the energetic requirements of encephalization are suggested to impose considerable constraints on brain size evolution. Three main hypotheses concerning how energetic constraints might affect brain evolution predict covariation between brain investment and (1) investment into other costly tissues, (2) overall metabolic rate, and (3) reproductive investment. To date, these hypotheses have mainly been tested in homeothermic animals and the existing data are inconclusive. However, there are good reasons to believe that energetic limitations might play a role in large-scale patterns of brain size evolution also in ectothermic vertebrates. Here, we test these hypotheses in a group of ectothermic vertebrates, the Lake Tanganyika cichlid fishes. After controlling for the effect of shared ancestry and confounding ecological variables, we find a negative association between brain size and gut size. Furthermore, we find that the evolution of a larger brain is accompanied by increased reproductive investment into egg size and parental care. Our results indicate that the energetic costs of encephalization may be an important general factor involved in the evolution of brain size also in ectothermic vertebrates.

  • 116.
    Tsuboi, Masahito
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Kotrschal, Alexander
    Stockholm Univ, Dept Zool Ethol, Svante Arrhenius Vag 18B, SE-10691 Stockholm, Sweden.
    Hayward, Alexander
    Stockholm Univ, Dept Zool Ethol, Svante Arrhenius Vag 18B, SE-10691 Stockholm, Sweden.
    Buechel, Séverine
    Stockholm Univ, Dept Zool Ethol, Svante Arrhenius Vag 18B, SE-10691 Stockholm, Sweden.
    Zidar, Josefina
    Linkoping Univ, IFM Biol, Campus Valla, SE-58183 Linkoping, Sweden.
    Løvlie, Hanne
    Linkoping Univ, IFM Biol, Campus Valla, SE-58183 Linkoping, Sweden.
    Kolm, Niclas
    Stockholm Univ, Dept Zool Ethol, Svante Arrhenius Vag 18B, SE-10691 Stockholm, Sweden.
    Evolution of brain-body allometry in Lake Tanganyika cichlids2016Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 70, nr 7, s. 1559-1568Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Brain size is strongly associated with body size at all taxonomic levels. This relationship has been hypothesized to be an important constraint on adaptive brain size evolution. The essential assumption of this idea is that allometry has a limited ability to evolve, and that evolution of relative brain size is therefore constrained to occur along the direction of static (i.e. within species) allometry. However, recent studies have reported mixed support for this view. Here, we examine if static allometry has affected the rate of relative brain size evolution in Lake Tanganyika cichlids. The evolution of brain-body allometry showed a recent rapid divergence whereas brain size evolution represented a more gradual phenotypic divergence across the history of diversification. Accordingly, we found no support for that static allometry affected the rate of absolute or relative brain size evolution in this group. Instead, we detected low, but existing evolvability of static allometry. Moreover, static allometry evolved faster in species with relatively small and large brains than in species with medium brain size. We propose that a combination of allometric constraints and partial evolvability of static allometry have allowed for independent evolution of brain size in Lake Tanganyika cichlids. Overall, our results demonstrate a complex, yet important, role of brain-body allometry in brain size evolution. 

  • 117.
    Vallin, Niclas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Rice, Amber M
    Bailey, Richard I
    Husby, Arild
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Qvarnström, Anna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Positive feedback between ecological and reproductive character displacement in a young avian hybrid zone2012Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 66, nr 4, s. 1167-1179Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Character displacement can reduce costly interspecific interactions between young species. We investigated the mechanisms behind divergence in three key traits—breeding habitat choice, timing of breeding, and plumage coloration—in Ficedula flycatchers. We found that male pied flycatchers became expelled from the preferred deciduous habitat into mixed forest as the superior competitor, collared flycatchers, increased in numbers. The peak in food abundance differs between habitats, and the spatial segregation was paralleled by an increased divergence in timing of breeding between the two species. Male pied flycatchers vary from brown to black with brown coloration being more frequent in sympatry with collared flycatchers, a pattern often proposed to result from selection against hybridization, that is, reinforcement. In contrast to this view, we show that brown male pied flycatchers more often hybridize than black males. Male pied flycatcher plumage coloration influenced the territory obtained in areas of co-occurrence with collared flycatchers, and brown male pied flycatchers experienced higher relative fitness than black males when faced with heterospecific competition. We suggest that allopatric divergence in resource defense ability causes a feedback loop at secondary contact where male pied flycatchers with the most divergent strategy compared to collared flycatchers are favored by selection.

  • 118. VanBuren, Collin S.
    et al.
    Campione, Nicolas E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Evans, David C.
    Head size, weaponry, and cervical adaptation: Testing craniocervical evolutionary hypotheses in Ceratopsia2015Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 69, nr 7, s. 1728-1744Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The anterior cervical vertebrae form the skeletal connection between the cranial and postcranial skeletons in higher tetrapods. As a result, the morphology of the atlas-axis complex is likely to be shaped by selection pressures acting on either the head or neck. The neoceratopsian (Reptilia:Dinosauria) syncervical represents one of the most highly modified atlas-axis regions in vertebrates, being formed by the complete coalescence of the three most anterior cervical vertebrae. In ceratopsids, the syncervical has been hypothesized to be an adaptation to support a massive skull, or to act as a buttress during intraspecific head-to-head combat. Here, we test these functional/adaptive hypotheses within a phylogenetic framework and critically examine the previously proposed methods for quantifying relative head size in the fossil record for the first time. Results indicate that neither the evolution of cranial weaponry nor large head size correlates with the origin of cervical fusion in ceratopsians, and we, therefore, reject both adaptive hypotheses for the origin of the syncervical. Anterior cervical fusion has evolved independently in a number of amniote clades, and further research on extant groups with this peculiar anatomy is needed to understand the evolutionary basis for cervical fusion in Neoceratopsia.

  • 119.
    Warsi, Omar M.
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Lundin, Erik
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Lustig, Ulrika
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Näsvall, Joakim
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Andersson, Dan I
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Selection for novel metabolic capabilities in Salmonella enterica2019Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 73, nr 5, s. 990-1000Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Bacteria are known to display extensive metabolic diversity and many studies have shown that they can use an extensive repertoire of small molecules as carbon‐ and energy sources. However, it is less clear to what extent a bacterium can expand its existing metabolic capabilities by acquiring mutations that, for example, rewire its metabolic pathways. To investigate this capability and potential for evolution of novel phenotypes, we sampled large populations of mutagenized Salmonella enterica to select very rare mutants that can grow on minimal media containing 124 low molecular weight compounds as sole carbon sources. We found mutants growing on 18 of these novel carbon sources, and identified the causal mutations that allowed growth for four of them. Mutations that relieve physiological constraints or increase expression of existing pathways were found to be important contributors to the novel phenotypes. For the remaining 14 novel phenotypes, whole genome sequencing of independent mutants and genetic analysis suggested that these novel metabolic phenotypes result from a combination of multiple mutations. This work, by virtue of identifying the genetic and mechanistic basis for new metabolic capabilities, sheds light on the properties of adaptive landscapes underlying the evolution of novel phenotypes.

  • 120.
    Wheatcroft, David
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Qvarnström, Anna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Reproductive character displacement of female, but not male song discrimination in an avian hybrid zone2017Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 71, nr 7, s. 1776-1786Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Divergence of male sexual signals and female preferences for those signals often maintains reproductive boundaries between closely related, co-occurring species. However, contrasting sources of selection, such as interspecific competition, can lead to weak divergence or even convergence of sexual signals in sympatry. When signals converge, assortative mating can be maintained if the mating preferences of females diverge in sympatry (reproductive character displacement; RCD), but there are few explicit examples. Pied flycatchers (Ficedula hypoleuca) are sympatric with collared flycatchers (F. albicollis) on the Baltic island of oland, where males from both species compete over nestboxes, their songs converge, and the two species occasionally hybridize. We compare song discrimination of male and female pied flycatchers on oland and in an allopatric population on the Swedish mainland. Using field choice trials, we show that male pied flycatchers respond similarly to the songs of both species in sympatry and allopatry, while female pied flycatchers express stronger discrimination against heterospecific songs in sympatry than in allopatry. These results are consistent with RCD of song discrimination of female pied flycatchers where they co-occur with collared flycatchers, which should maintain species assortative mating despite convergence of male sexual signals.

  • 121.
    Wiley, Chris
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Zooekologi.
    Qvarnström, Anna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Zooekologi.
    Andersson, Gunilla
    Borge, Thomas
    Saetre, Glenn-Peter
    POSTZYGOTIC ISOLATION OVER MULTIPLE GENERATIONS OF HYBRID DESCENDENTS IN A NATURAL HYBRID ZONE: HOW WELL DO SINGLE-GENERATION ESTIMATES REFLECT REPRODUCTIVE ISOLATION?2009Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 63, nr 7, s. 1731-1739Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Understanding speciation depends on an accurate assessment of the reproductive barriers separating newly diverged populations. In several taxonomic groups, prezygotic barriers, especially preferences for conspecific mates, are thought to play the dominant role in speciation. However, the importance of postzygotic barriers (i.e., low fitness of hybrid offspring) may be widely underestimated. In this study, we examined how well the widely used proxy of postzygotic isolation (reproductive output of F1 hybrids) reflects the long-term fitness consequences of hybridization between two closely related species of birds. Using 40 species-specific single nucleotide polymorphism (SNP) markers, we genotyped a mixed population of collared and pied flycatchers (Ficedula albicollis and F. hypoleuca) to identify grand- and great grand-offspring from interspecific crosses to derive an accurate, multigeneration estimate of postzygotic isolation. Two independent estimates of fitness show that hybridization results in 2.4% and 2.7% of the number of descendents typical of conspecific pairing. This postzygotic isolation was considerably stronger than estimates based on F1 hybrids. Our results demonstrate that, in nature, combined selection against hybrids and backcrossed individuals may result in almost complete postzygotic isolation between two comparatively young species. If these findings are general, postzygotic barriers separating hybridizing populations may be much stronger than previously thought.

  • 122.
    Wright, Dominic
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Kerje, Susanne
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Brändström, Helena
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Schütz, Karin
    Kindmark, Andreas
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Andersson, Leif
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Jensen, Per
    Pizzari, Tommaso
    The genetic architecture of a female sexual ornament2008Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 62, nr 1, s. 86-98Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Understanding the evolution of sexual ornaments, and particularly that of female sexual ornaments, is an enduring challenge in evolutionary biology. Key to this challenge are establishing the relationship between ornament expression and female reproductive investment, and determining the genetic basis underpinning such relationship. Advances in genomics provide unprecedented opportunities to study the genetic architecture of sexual ornaments in model species. Here, we present a quantitative trait locus (QTL) analysis of a female sexual ornament, the comb of the fowl, Gallus gallus, using a large-scale intercross between red junglefowl and a domestic line, selected for egg production. First, we demonstrate that female somatic investment in comb reflects female reproductive investment. Despite a trade-off between reproductive and skeletal investment mediated by the mobilization of skeletal minerals for egg production, females with proportionally large combs also had relatively high skeletal investment. Second, we identify a major QTL for bisexual expression of comb mass and several QTL specific to female comb mass. Importantly, QTL for comb mass were nonrandomly clustered with QTL for female reproductive and skeletal investment on chromosomes one and three. Together, these results shed light onto the physiological and genetic architecture of a female ornament.

  • 123.
    Zhang, Lai
    et al.
    Yangzhou Univ, Sch Math Sci, Yangzhou 225002, Jiangsu, Peoples R China;Umea Univ, Dept Math & Math Stat, SE-90187 Umea, Sweden.
    Thibert-Plante, Xavier
    Umea Univ, Dept Ecol & Environm Sci, SE-90187 Umea, Sweden.
    Ripe, Jorgen
    Lund Univ, Dept Biol, Theoret Populat Ecol & Evolut Grp, S-22362 Lund, Sweden.
    Svanbäck, Richard
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Brannstrom, Ake
    Umea Univ, Dept Math & Math Stat, SE-90187 Umea, Sweden;Int Inst Appl Syst Anal, Evolut & Ecol Program, A-2361 Laxenburg, Austria.
    Biodiversity loss through speciation collapse: Mechanisms, warning signals, and possible rescue2019Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 73, nr 8, s. 1504-1516Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Speciation is the process that generates biodiversity, but recent empirical findings show that it can also fail, leading to the collapse of two incipient species into one. Here, we elucidate the mechanisms behind speciation collapse using a stochastic individual-based model with explicit genetics. We investigate the impact of two types of environmental disturbance: deteriorated visual conditions, which reduce foraging ability and impede mate choice, and environmental homogenization, which restructures ecological niches. We find that: (1) Species pairs can collapse into a variety of forms including new species pairs, monomorphic or polymorphic generalists, or single specialists. Notably, polymorphic generalist forms may be a transient stage to a monomorphic population; (2) Environmental restoration enables species pairs to reemerge from single generalist forms, but not from single specialist forms; (3) Speciation collapse is up to four orders of magnitude faster than speciation, while the reemergence of species pairs can be as slow as de novo speciation; (4) Although speciation collapse can be predicted from either demographic, phenotypic, or genetic signals, observations of phenotypic changes allow the most general and robust warning signal of speciation collapse. We conclude that factors altering ecological niches can reduce biodiversity by reshaping the ecosystem's evolutionary attractors.

  • 124.
    Zwoinska, Martyna K.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Lind, Martin I.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Cortazar-Chinarro, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Ramsden, Mark
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Maklakov, Alexei A.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Selection on learning performance results in the correlated evolution of sexual dimorphism in life history2016Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 70, nr 2, s. 342-357Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The evolution of learning can be constrained by trade-offs. As male and female life histories often diverge, the relationship between learning and fitness may differ between the sexes. However, because sexes share much of their genome, intersexual genetic correlations can prevent males and females from reaching their sex-specific optima resulting in intralocus sexual conflict (IaSC). To investigate if IaSC constraints sex-specific evolution of learning, we selected Caenorhabditis remanei nematode females for increased or decreased olfactory learning performance and measured learning, life span (in mated and virgin worms), reproduction, and locomotory activity in both sexes. Males from downward-selected female lines had higher locomotory activity and longer virgin life span but sired fewer progeny than males from upward-selected female lines. In contrast, we found no effect of selection on female reproduction and downward-selected females showed higher locomotory activity but lived shorter as virgins than upward-selected females. Strikingly, selection on learning performance led to the reversal of sexual dimorphism in virgin life span. We thus show sex-specific trade-offs between learning, reproduction, and life span. Our results support the hypothesis that selection on learning performance can shape the evolution of sexually dimorphic life histories via sex-specific genetic correlations.

  • 125.
    Zwoinska, Martyna K.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi. Univ Lausanne, Dept Ecol & Evolut, CH-1015 Lausanne, Switzerland..
    Maklakov, Alexei A.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Kawecki, Tadeusz J.
    Univ Lausanne, Dept Ecol & Evolut, CH-1015 Lausanne, Switzerland..
    Hollis, Brian
    Univ Lausanne, Dept Ecol & Evolut, CH-1015 Lausanne, Switzerland.;Ecole Polytech Fed Lausanne, Sch Life Sci, Lausanne, Switzerland..
    Experimental evolution of slowed cognitive aging in Drosophila melanogaster2017Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 71, nr 3, s. 662-670Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Reproductive output and cognitive performance decline in parallel during aging, but it is unknown whether this reflects a shared genetic architecture or merely the declining force of natural selection acting independently on both traits. We used experimental evolution in Drosophila melanogaster to test for the presence of genetic variation for slowed cognitive aging, and assess its independence from that responsible for other traits' decline with age. Replicate experimental populations experienced either joint selection on learning and reproduction at old age (Old + Learning), selection on late-life reproduction alone (Old), or a standard two-week culture regime (Young). Within 20 generations, the Old + Learning populations evolved a slower decline in learning with age than both the Old and Young populations, revealing genetic variation for cognitive aging. We found little evidence for a genetic correlation between cognitive and demographic aging: although the Old + Learning populations tended to show higher late-life fecundity than Old populations, they did not live longer. Likewise, selection for late reproduction alone did not result in improved late-life learning. Our results demonstrate that Drosophila harbor genetic variation for cognitive aging that is largely independent from genetic variation for demographic aging and suggest that these two aspects of aging may not necessarily follow the same trajectories.

  • 126.
    Ågren, Jon
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Oakley, Christopher G.
    Michigan State Univ, Dept Plant Biol, E Lansing, MI 48824 USA. WWF Norway, Postboks 6784, N-0130 Oslo, Norway..
    Lundemo, Sverre
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Schemske, Douglas W.
    Michigan State Univ, Dept Plant Biol, E Lansing, MI 48824 USA.;Michigan State Univ, WK Kellogg Biol Stn, E Lansing, MI 48824 USA..
    Adaptive divergence in flowering time among natural populations of Arabidopsis thaliana: Estimates of selection and QTL mapping2017Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 71, nr 3, s. 550-564Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To identify the ecological and genetic mechanisms of local adaptation requires estimating selection on traits, identifying their genetic basis, and evaluating whether divergence in adaptive traits is due to conditional neutrality or genetic trade-offs. To this end, we conducted field experiments for three years using recombinant inbred lines (RILs) derived from two ecotypes of Arabidopsis thaliana (Italy, Sweden), and at each parental site examined selection on flowering time and mapped quantitative trait loci (QTL). There was strong selection for early flowering in Italy, but weak selection in Sweden. Eleven distinct flowering time QTL were detected, and for each the Italian genotype caused earlier flowering. Twenty-seven candidate genes were identified, two of which (FLC and VIN3) appear under major flowering time QTL in Italy. Seven of eight QTL in Italy with narrow credible intervals colocalized with previously reported fitness QTL, in comparison to three of four in Sweden. The results demonstrate that the magnitude of selection on flowering time differs strikingly between our study populations, that the genetic basis of flowering time variation is multigenic with some QTL of large effect, and suggest that divergence in flowering time between ecotypes is due mainly to conditional neutrality.

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