Inbreeding and Outbreeding Depression in Male Courtship Song Characters in Drosophila Montana

Total Page:16

File Type:pdf, Size:1020Kb

Inbreeding and Outbreeding Depression in Male Courtship Song Characters in Drosophila Montana Heredity 84 (2000) 273±282 Received 9 June 1999, accepted 14 October 1999 Inbreeding and outbreeding depression in male courtship song characters in Drosophila montana JOUNI ASPI University of Oulu, Department of Biology, PO Box 3000, FIN-90401 Oulu, Finland In Drosophila montana, male courtship song frequency is closely associated with male courtship success and ospring survival. Other pulse characters (pulse length and cycle number) may also aect female mate choice, whereas pulse train characters (interpulse interval, pulse number and pulse train length) are not associated with these male ®tness components. Inbreeding depression in these song characters was investigated by comparing the songs of inbred and outbred ¯y strains. The average change in most song characters as a result of inbreeding was only a few percent. However, in male song frequency the average inbreeding depression was about 14%, suggesting that this song character is associated with ®tness. Outbreeding depression and the genetic architecture of song characters were investigated with interpopulation crosses and joint scaling tests. For pulse train characters the generation means show only evidence of additivity, and the existence of dominance or epistasis in these characters was strongly rejected in each case. In pulse characters the means of the F1 males were lower than the average of the parental generations. In pulse length and cycle number this dierence was attributable to dominance alone. In frequency there was outbreeding depression also in the F2 generation, suggesting a break-up of favourable epistatic gene combinations. The outbreeding depression in this character in the F1 generation was caused by dominance, and in the F2 also by duplicate epistasis between dominant decreasers. The possible role of outbreeding depression and epistasis in speciation is discussed. Keywords: courtship song, epistasis, interpopulation hybrids, shifting balance theory. Introduction usually attributed to a break-up of favourable epistatic interactions in the parental lines, or phenotype±envi- The most striking observed consequence of inbreeding ronment interaction (Thornhill, 1993; Lynch & Walsh, is the reduction of the mean phenotypic value shown 1998; Wade & Goodnight, 1998). by characters connected with ®tness, the phenomenon In Drosophila montana, some courtship song charac- known as inbreeding depression (Falconer, 1985; ters are associated with male ®tness. Courtship song in Thornhill, 1993). Under inbreeding, primary ®tness this species consists of a train of polycyclic sound pulses characters tend to exhibit very high levels of inbreeding (Fig. 1). In the wild, females prefer males that produce depression, whereas characters more remotely related to short and dense sound pulses, a combination which ®tness change normally show only low levels (Lynch & leads to a high carrier frequency (Aspi & Hoikkala, Walsh, 1998; De Rose & Ro, 1999). On the other hand, 1995). Pulse train characters, i.e. the interpulse interval, extreme outcrossing may also decrease ospring ®tness; length of a pulse train and number of pulses in a pulse for example, in crosses between distantly related popu- train, do not seem to aect female choice (Aspi & lations, F1 and/or F2 generations are sometimes less ®t Hoikkala, 1995). These results have been con®rmed by than the average of the original parental strains (Wu & Ritchie et al. (1998) under laboratory conditions by Palopoli, 1994; Lynch & Walsh, 1998). This phenom- using simulated background songs. enon is known as outbreeding depression, and it is Male courtship song frequency is also associated with another ®tness component. It is correlated with the survival rate of the male's progeny from egg to *Correspondence: Jouni Aspi, University of Oulu, Department of Biology, PO Box 3000, 90401 Oulu, Finland. Tel: 358-8-5531788; adulthood (Hoikkala et al., 1998). Accordingly, male Fax: 358-8-5531061; E-mail: jouni.aspi@oulu.® song frequency can act as a reliable indicator of male Ó 2000 The Genetical Society of Great Britain. 273 274 J. ASPI Fig. 1 Oscillograms of male courtship songs in inbred strains K12/20 and 1550/ 20 of Drosophila montana. ®tness for females. By choosing a male with courtship eastern Finland (66°25¢N, 29°0¢E). The strain 1550/20 is song frequency one standard deviation higher than the from Yukon, Alaska (61°30¢N, 159°20¢W) and the strain average in the population, a female could increase the 1263/20 from Kawasaki, Japan (34°80¢N, 139°60¢E). viability of her ospring by about 24% (Hoikkala et al., The absence of genetic variation in strains K12/20 and 1998). The other song characters are not associated with 1550/20 has been tested by using RAPD-markers. No ospring survival (Hoikkala et al., 1998). variation within strains was found by using 90 RAPD- Even though the consequences of inbreeding have been markers even though 20 of these markers appeared to studied in several ®tness-related traits (Lynch & Walsh, dier between strains (J. Aspi, unpubl. obs.). 1998; De Rose & Ro, 1999), there have been relatively As outbred ¯ies I used the males of two laboratory few studies designed to investigate the eects of inbreed- strains, 1251 and 1263, from which the inbred lines 1251/ ing on behavioural traits (but see Miller et al., 1993). 20 and 1263/20 originated (the original laboratory strain Data on outbreeding depression in interpopulation of inbred 1550 strain was no longer available). I also used hybrids, especially in animals, are also sparse (Thornhill, F1 male ospring of wild-caught males from a natural 1993). The aim of this study is to investigate possible population near the town of Kemi (from where the strain inbreeding depression and outbreeding depression in K12/20 originated). F1 males were used instead of wild- ®tness-related and non-®tness-related male courtship caught males because songs of D. montana males raised song characters in D. montana. We would expect to ®nd under laboratory conditions seem to dier from those inbreeding depression in pulse characters, especially in of wild-caught males (Aspi & Hoikkala, 1993). These male courtship song frequency, whereas there should not dierences are caused by larger phenotypic variability of be changes in the means of pulse train characters. song characters in the ®eld and also by genotype± Drosophila montana also provides a good opportunity environment interactions (Aspi & Hoikkala, 1993). to study possible outbreeding depression. This species has As the inbred strains K12/20 and 1550/20 strains were a very wide circum-Arctic distribution range (Throck- the most dissimilar ones with respect to male song morton, 1982), and thus it is possible that crosses between characters, and were from the opposite ends of the distant allopatric populations could lead to a signi®cant distribution range, I used these strains to study possible outbreeding depression in some male song characters. outbreeding depression or heterosis. There was a signi®- cant dierence in each male song character between these strains (see Table 2). Parental, and also F ,F and Materials and methods 1 2 backcross generations between parental strains, includ- ing all reciprocals, were raised under similar conditions. Flies and crosses Flies were maintained in culture bottles containing The inbred strains of D. montana used have been inbred malt medium, in continuous light at 19°C. These condi- for 20 generations by brother±sister matings to render tions approximate conditions in the wild when the ¯ies the strains homozygous. The strains originated from mate at northern latitudes. Freshly emerged ¯ies were dierent parts of the species' distribution range. The sexed under light CO2 anaesthesia and maintained in strain K12/20 is from Kemi, northern Finland (65°40¢N, food vials. Flies were used in experiments at the age of 3 23°35¢E) and the strain 1251/20 from Oulanka, north- weeks old, when sexually mature. Ó The Genetical Society of Great Britain, Heredity, 84, 273±282. INBREEDING AND OUTBREEDING DEPRESSION IN MALE SONG 275 where X is the vector of mean, additive, dominance and Song recording and analysis digenic epistatic parameters, m,[a], [d ], [aa], [ad ] and The courtship song of D. montana comprises polycyclic [dd], respectively. C is the matrix of coecients for these sound pulses (Fig. 1). The song of each male was parameters from the equation for predicted family recorded with a Sony TC-FX33 cassette recorder means, W is the diagonal matrix of weights (i.e. the and a JVC-condenser microphone. Song analysis was reciprocals of the variances of the generation means), carried out using the Signal Sound Analysis System and Y is the vector of generation means. The variances (Ó Engineering Design). I measured the lengths of the of the parameter estimates can be obtained from the pulse trains (PTL) and counted the number of pulses per diagonal elements of (C¢WC)±1 given that the model is train (PN) in oscillograms made of the songs. I also adequate (i.e. the chi-squared statistic is not signi®cant). counted the number of cycles (CN) in the fourth sound The observed generation means were ®rst tested for ®t to pulse of each pulse train, and measured the length of this models incorporating only m, m and [a], and m,[a] and pulse (pulse length, PL) and the distance from the [d ], successively. The expected means of the six genera- beginning of this pulse to the beginning of the next one tions were calculated using the parameter estimates, the (interpulse interval, IPI). Carrier frequency of the song goodness-of-®t of the observed generation means was (FRE) was measured from Fourier spectra. For statis- tested with the chi-squared statistic, and the signi®cance tical analysis, PL, FRE, IPI and PTL were transformed of each parameter was tested by using a t-test (Mather & to natural logarithms. Jinks, 1982; Kearsey & Pooni, 1996). The more complex Only one pulse train per male was analysed because the model was applied only if the chi-squared test revealed repeatabilities of most of the song characters have been that the simpler model was inadequate.
Recommended publications
  • Priority Actions to Improve Provenance Decision-Making
    Forum Priority Actions to Improve Provenance Decision-Making MARTIN F. BREED, PETER A. HARRISON, ARMIN BISCHOFF, PAULA DURRUTY, NICK J. C. GELLIE, EMILY K. GONZALES, KAYRI HAVENS, MARION KARMANN, FRANCIS F. KILKENNY, SIEGFRIED L. KRAUSS, ANDREW J. LOWE, PEDRO MARQUES, PAUL G. NEVILL, PATI L. VITT, AND ANNA BUCHAROVA Selecting the geographic origin—the provenance—of seed is a key decision in restoration. The last decade has seen a vigorous debate on whether to use local or nonlocal seed. The use of local seed has been the preferred approach because it is expected to maintain local adaptation and avoid deleterious population effects (e.g., maladaptation and outbreeding depression). However, the impacts of habitat fragmentation and climate change on plant populations have driven the debate on whether the local-is-best standard needs changing. This debate has largely been theoretical in nature, which hampers provenance decision-making. Here, we detail cross-sector priority actions to improve provenance decision-making, including embedding provenance trials into restoration projects; developing dynamic, evidence-based provenance policies; and establishing stronger research–practitioner collaborations to facilitate the adoption of research outcomes. We discuss how to tackle these priority actions in order to help satisfy the restoration sector’s requirement for appropriately provenanced seed. Keywords: assisted migration, ecological restoration, local adaptation, restoration genetics he restoration sector’s demand for seed is Williams et al. 2014, Havens et al. 2015, Prober et al. 2015, Tenormous and is rapidly increasing with the growth Breed et al. 2016b, Christmas et al. 2016b). in the global restoration effort (Verdone and Seidl 2017).
    [Show full text]
  • The Evolution, Diversity, and Host Associations of Rhabdoviruses Ben Longdon,1,* Gemma G
    Virus Evolution, 2015, 1(1): vev014 doi: 10.1093/ve/vev014 Research article The evolution, diversity, and host associations of rhabdoviruses Ben Longdon,1,* Gemma G. R. Murray,1 William J. Palmer,1 Jonathan P. Day,1 Darren J Parker,2,3 John J. Welch,1 Darren J. Obbard4 and Francis M. Jiggins1 1 2 Department of Genetics, University of Cambridge, Cambridge, CB2 3EH, School of Biology, University of Downloaded from St Andrews, St Andrews, KY19 9ST, UK, 3Department of Biological and Environmental Science, University of Jyva¨skyla¨, Jyva¨skyla¨, Finland and 4Institute of Evolutionary Biology, and Centre for Immunity Infection and Evolution, University of Edinburgh, Edinburgh, EH9 3JT, UK *Corresponding author: E-mail: [email protected] http://ve.oxfordjournals.org/ Abstract Metagenomic studies are leading to the discovery of a hidden diversity of RNA viruses. These new viruses are poorly characterized and new approaches are needed predict the host species these viruses pose a risk to. The rhabdoviruses are a diverse family of RNA viruses that includes important pathogens of humans, animals, and plants. We have discovered thirty-two new rhabdoviruses through a combination of our own RNA sequencing of insects and searching public sequence databases. Combining these with previously known sequences we reconstructed the phylogeny of 195 rhabdovirus by guest on December 14, 2015 sequences, and produced the most in depth analysis of the family to date. In most cases we know nothing about the biology of the viruses beyond the host they were identified from, but our dataset provides a powerful phylogenetic approach to predict which are vector-borne viruses and which are specific to vertebrates or arthropods.
    [Show full text]
  • Modeling Factors Affecting the Severity of Outbreeding Depression
    Modeling Factors Affecting the Severity of Outbreeding Depression SUZANNE EDMANDS* AND CHARLES C. TIMMERMAN† *Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, U.S.A., email [email protected] †997 West 30th Street, Los Angeles CA 90007, U.S.A. Abstract: Hybridization between populations may cause either increased fitness (“hybrid vigor”) or de- creased fitness (“outbreeding depression”). Translocation between populations may therefore in some cases be a successful means of combating genetic erosion and preserving evolutionary potential, whereas in other cases it may make the situation worse by inducing outbreeding depression. Because genetic distance alone is a poor predictor of the success or failure of hybridization, we developed a computer model (ELAB) to explore other factors affecting the consequences of hybridization. Our model simulates diploid, unisexual popula- tions following Mendelian rules, and in this study we used it to test the effect of a variety of parameters on both the magnitude and duration of outbreeding depression. We focused our simulations on the effects of (1) divergence between populations, (2) the genetic basis of outbreeding depression (disruption of local adap- tation vs. intrinsic coadaptation), (3) population parameters such as mutation rate and recombination rate, and (4) alternative management schemes (50:50 mixture vs. one migrant per generation). The magnitude of outbreeding depression increased linearly with genetic distance, whereas the duration of outbreeding de- pression showed a more complex curvilinear relationship. With genetic distance held constant, magnitude in- creased with larger population size, lower mutation rate, cross-fertilization, and higher recombination rate, whereas duration increased with larger population size and partial self-fertilization.
    [Show full text]
  • Examining Genetic Diversity, Outbreeding Depression, and Local Adaptation in a Native Fish Reintroduction Program a DISSERTATION
    Examining genetic diversity, outbreeding depression, and local adaptation in a native fish reintroduction program A DISSERTATION SUBMITTED TO THE FACULTY OF THE GRADUATE SCHOOL OF THE UNIVERSITY OF MINNESOTA BY DAVID DERLAND HUFF IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY BRUCE VONDRACEK AND RAYMOND M. NEWMAN, CO-ADVISORS May 2010 © David Derland Huff, 2010 Acknowledgements I am grateful to so many people for their contributions to my work and well-being during my time at the University of Minnesota that is difficult for me to know where to begin. I will start with Bruce Vondracek, who was very involved in this research and went out of his way to make himself available, even on short notice. He was instrumental in helping me obtain resources and funding for research and somehow scrounged funds for travel on every occasion that I asked for it. We also enjoyed many fishing trips in which we cumulatively landed thousands of trout. He always out-fished me no matter how hard I tried, except once, thanks to one ugly little green fly. Austen Cargill II provided me with a fellowship (and the aforementioned green fly) for the duration of my time in Minnesota and was also present on most of our fishing trips. I would like to thank him for this funding and for his generous hospitality, interesting conversations, and valuable fly-fishing advice. Funding was also provided by a doctoral dissertation fellowship from the Graduate School of the University of Minnesota. The Minnesota Department of Natural Resources, U.S.
    [Show full text]
  • Revegetation Priorities D
    Revegetation Priorities D. Terrance Booth and Kenneth P. Vogel Introduction A cultivar is a variety, strain, or population of known genetic Revegetation is a needed means of mitigating man-made and origin, produced under cultivation in a way to ensure its natural disturbance. Our current ability to address environ- genetic integrity is maintained. mental insults contrasts sharply with that existing when John Muir fi rst sowed the roots of environmental awareness or Aldo Leopold and Hugh H. Bennett inspired a land ethic and a sense of stewardship. We now have considerable revegeta- There is agreement among land managers, Federal and tion science and experience and—equally important—viable state agencies, conservation groups, and scientists that the native-seed and revegetation industries expert in repairing decisions should be based on research and science. There are environmental damage. Through the National Plant Mate- hundreds of species on the rangelands of North America and rials program, related and usually cooperative work within rigorous genetic and adaptation studies have been conducted state universities and other entities, and the development of on only a few, so the scientifi c information base is small in ecological service industries, our society has heeded Leop- comparison to that of cultivated crops. Our intent here is to old’s call to take pride in the “husbandry” of wild plants.1 Yet, summarize key aspects of this problem, suggest some potential wild-plant husbandry is now being questioned, as is the wis- approaches and solutions, and encourage further research. dom of much of the knowledge, experience, and use of plant materials developed over the past 3 to 5 decades.
    [Show full text]
  • Evaluating the Relative Risks of Inbreeding and Outbreeding for Conservation and Management
    Molecular Ecology (2007) 16, 463–475 doi: 10.1111/j.1365-294X.2006.03148.x INVITEDBlackwell Publishing Ltd REVIEW Between a rock and a hard place: evaluating the relative risks of inbreeding and outbreeding for conservation and management SUZANNE EDMANDS Department of Biological Sciences, AHF 107, University of Southern California, Los Angeles, CA 90089-0371, USA Abstract As populations become increasingly fragmented, managers are often faced with the dilemma that intentional hybridization might save a population from inbreeding depression but it might also induce outbreeding depression. While empirical evidence for inbreeding depression is vastly greater than that for outbreeding depression, the available data suggest that risks of outbreeding, particularly in the second generation, are on par with the risks of inbreeding. Predicting the relative risks in any particular situation is complicated by vari- ation among taxa, characters being measured, level of divergence between hybridizing populations, mating history, environmental conditions and the potential for inbreeding and outbreeding effects to be occurring simultaneously. Further work on consequences of interpopulation hybridization is sorely needed with particular emphasis on the taxonomic scope, the duration of fitness problems and the joint effects of inbreeding and outbreeding. Meanwhile, managers can minimize the risks of both inbreeding and outbreeding by using intentional hybridization only for populations clearly suffering from inbreeding depression, maximizing the genetic and adaptive similarity between populations, and testing the effects of hybridization for at least two generations whenever possible. Keywords: fitness, hybridization, inbreeding depression, outbreeding depression Received 21 May 2006; revision accepted 1 September 2006 times more fit than the resident lineages (Ebert et al.
    [Show full text]
  • Mixed-Source Reintroductions Lead to Outbreeding Depression in Second-Generation Descendents of a Native North American Fish
    University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Nebraska Cooperative Fish & Wildlife Research Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications Unit 2011 Mixed-source reintroductions lead to outbreeding depression in second-generation descendents of a native North American fish David D. Huff University of Minnesota, [email protected] Loren M. Miller University of Minnesota Christopher J. Chizinski University of Minnesota, [email protected] Bruce Vondracek University of Minnesota, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/ncfwrustaff Part of the Aquaculture and Fisheries Commons, Environmental Indicators and Impact Assessment Commons, Environmental Monitoring Commons, Natural Resource Economics Commons, Natural Resources and Conservation Commons, and the Water Resource Management Commons Huff, David D.; Miller, Loren M.; Chizinski, Christopher J.; and Vondracek, Bruce, "Mixed-source reintroductions lead to outbreeding depression in second-generation descendents of a native North American fish" (2011). Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications. 194. https://digitalcommons.unl.edu/ncfwrustaff/194 This Article is brought to you for free and open access by the Nebraska Cooperative Fish & Wildlife Research Unit at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications by an authorized administrator of DigitalCommons@University
    [Show full text]
  • Outbreeding Depression As a Selective Force on Mixed Mating in the Mangrove Rivulus Fish, Kryptolebias Marmoratus
    bioRxiv preprint doi: https://doi.org/10.1101/2021.02.22.432322; this version posted February 22, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Outbreeding depression as a selective force on mixed mating in the mangrove rivulus fish, Kryptolebias marmoratus bioRxiv preprint doi: https://doi.org/10.1101/2021.02.22.432322; this version posted February 22, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Abstract Mixed mating, a reproduction strategy utilized by many plants and invertebrates, optimizes the cost to benefit ratio of a labile mating system. One type of mixed mating includes outcrossing with conspecifics and self-fertilizing one’s own eggs. The mangrove rivulus fish (Kryptolebias marmoratus) is one of two vertebrates known to employ both self-fertilization (selfing) and outcrossing. Variation in rates of outcrossing and selfing within and among populations produces individuals with diverse levels of heterozygosity. I designed an experiment to explore the consequences of variable heterozygosity across four ecologically relevant conditions of salinity and water availability (10‰, 25‰, and 40‰ salinity, and twice daily tide changes). I report a significant increase in mortality in the high salinity (40‰) treatment. I also report significant effects on fecundity measures with increasing heterozygosity. The odds of laying eggs decreased with increasing heterozygosity across all treatments, and the number of eggs laid decreased with increasing heterozygosity in the 10‰ and 25‰ treatments.
    [Show full text]
  • Homozygosity at Its Limit: Inbreeding Depression in Wild Arabidopsis Arenosa Populations
    bioRxiv preprint doi: https://doi.org/10.1101/2021.01.24.427284; this version posted January 25, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. Barragan et al. Inbreeding Depression in A. arenosa Homozygosity at its Limit: Inbreeding Depression in Wild Arabidopsis arenosa Populations A. Cristina Barragan1, Maximilian Collenberg1, Rebecca Schwab1, Merijn Kerstens1a, Ilja Bezrukov1, Felix Bemm1,b, Doubravka Požárová2, Filip Kolář2, Detlef Weigel1* 1Department of Molecular Biology, Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany 2Department of Botany, Faculty of Science, Charles University, 128 01 Prague, Czech Republic aCurrent address: Department of Plant Developmental Biology, Wageningen University and Research, 6708 PB, Wageningen, Netherlands bCurrent address: KWS Saat, 37574 Einbeck, Germany *Corresponding author: [email protected] (D.W.) Keywords: Arabidopsis arenosa, wild populations, deleterious phenotypes, inbreeding depression Abstract New combinations of genetic material brought together through hybridization can lead to unfit offspring as a result of outbreeding or inbreeding depression. In selfing plants such as Arabidopsis thaliana, outbreeding depression is typically the result of pairwise deleterious epistatic interactions between two alleles that can geographically co-occur. What remains elusive is how often alleles resulting in genetic incompatibilities co-occur in natural populations of outcrossing plant species. To address this question, we screened over two thousand five hundred wild Arabidopsis arenosa hybrid plants in search for potential genetic mismatches. We show that although abnormal deleterious phenotypes are common, the transcriptional profiles of these abnormal A.
    [Show full text]
  • Evolutionary History and Genetic Connectivity Across Highly Fragmented Populations of an Endangered Daisy
    Heredity (2021) 126:846–858 https://doi.org/10.1038/s41437-021-00413-0 ARTICLE Evolutionary history and genetic connectivity across highly fragmented populations of an endangered daisy 1 1 2 3 1 Yael S. Rodger ● Alexandra Pavlova ● Steve Sinclair ● Melinda Pickup ● Paul Sunnucks Received: 29 May 2020 / Revised: 24 January 2021 / Accepted: 25 January 2021 / Published online: 19 February 2021 © The Author(s) 2021. This article is published with open access Abstract Conservation management can be aided by knowledge of genetic diversity and evolutionary history, so that ecological and evolutionary processes can be preserved. The Button Wrinklewort daisy (Rutidosis leptorrhynchoides) was a common component of grassy ecosystems in south-eastern Australia. It is now endangered due to extensive habitat loss and the impacts of livestock grazing, and is currently restricted to a few small populations in two regions >500 km apart, one in Victoria, the other in the Australian Capital Territory and nearby New South Wales (ACT/NSW). Using a genome-wide SNP dataset, we assessed patterns of genetic structure and genetic differentiation of 12 natural diploid populations. We estimated intrapopulation genetic diversity to scope sources for genetic management. Bayesian clustering and principal coordinate 1234567890();,: 1234567890();,: analyses showed strong population genetic differentiation between the two regions, and substantial substructure within ACT/ NSW. A coalescent tree-building approach implemented in SNAPP indicated evolutionary divergence between the two distant regions. Among the populations screened, the last two known remaining Victorian populations had the highest genetic diversity, despite having among the lowest recent census sizes. A maximum likelihood population tree method implemented in TreeMix suggested little or no recent gene flow except potentially between very close neighbours.
    [Show full text]
  • Cognitive Mechanisms Underlying Responses to Sperm Competition in Drosophila Melanogaster
    Cognitive mechanisms underlying responses to sperm competition in Drosophila melanogaster James Luke Rouse Submitted in accordance with the requirements for the degree of Doctor of Philosophy The University of Leeds School of Biology November 2016 The candidate confirms that the work submitted is his/her own, except where work which has formed part of jointly-authored publications has been included. The contribution of the candidate and the other authors to this work has been explicitly indicated below. The candidate confirms that appropriate credit has been given within the thesis where reference has been made to the work of others. Jointly authored publications Rouse, J. Bretman, A. (2016) Exposure time to rivals and sensory cues affect how quickly males respond to changes in sperm competition threat, Animal Behaviour, 122, 1-8 All experimental work was carried out by the author of this thesis; manuscript preparation was jointly shared between the authors This copy has been supplied on the understanding that it is copyright material and that no quotation from the thesis may be published without proper acknowledgement. © 2016 The University of Leeds and James Luke Rouse ii Acknowledgments I doubt many people will read this Thesis too closely, but from personal experience I know the acknowledgments are scrutinised, so I better make them good. First and foremost, I would like to thank my supervisor Amanda for providing me with the opportunity to perform this work. From helping me understand statistics as a baby-faced undergraduate she has encouraged and cajoled me to the baby-faced 24 year old I am today.
    [Show full text]
  • Daily Activity of the Housefly, Musca Domestica, Is Influenced By
    INVESTIGATION Daily Activity of the Housefly, Musca domestica,Is Influenced by Temperature Independent of 39 UTR period Gene Splicing Olga Bazalova*,† and David Dolezel*,†,1 ˇ † *Biology Center, Czech Academy of Sciences, 37005 Ceské Budejovice,ˇ Czech Republic and Department of Molecular ˇ Biology, Faculty of Sciences, University of South Bohemia, 37005 Ceské Budejovice,ˇ Czech Republic ORCID ID: 0000-0001-9176-8880 (D.D.) ABSTRACT Circadian clocks orchestrate daily activity patterns and free running periods of locomotor KEYWORDS activity under constant conditions. While the first often depends on temperature, the latter is temperature- temperature compensated over a physiologically relevant range. Here, we explored the locomotor activity of the compensation temperate housefly Musca domestica. Under low temperatures, activity was centered round a major and of circadian broad afternoon peak, while high temperatures resulted in activity throughout the photophase with a mild rhythms midday depression, which was especially pronounced in males exposed to long photoperiods. While period locomotor (per) mRNA peaked earlier under low temperatures, no temperature-dependent splicing of the last per 3ʹ activity end intron was identified. The expression of timeless, vrille, and Par domain protein 1 was also influenced by transcription temperature, each in a different manner. Our data indicated that comparable behavioral trends in daily mRNA splicing activity distribution have evolved in Drosophila melanogaster and M. domestica, yet the behaviors of these circadian clock two species are orchestrated by different molecular mechanisms. genes Circadian clocks are ubiquitous adaptations to periodic day/night Temperature strongly affects the weak splice site of the last period alternations and orchestrate metabolic and behavioral activities of many (per) gene intron (dmpi8) and locomotor activity pattern of D.
    [Show full text]