1
|
Lush J, Sgrò CM, Hall MD. Anticipating change: The impact of simulated seasonal heterogeneity on heat tolerances along a latitudinal cline. Ecology 2024; 105:e4359. [PMID: 38877760 DOI: 10.1002/ecy.4359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 01/18/2024] [Accepted: 02/19/2024] [Indexed: 06/16/2024]
Abstract
An understanding of thermal limits and variation across geographic regions is central to predicting how any population may respond to global change. Latitudinal clines, in particular, have been used to demonstrate that populations can be locally adapted to their own thermal environment and, as a result, not all populations will be equally impacted by an increase in temperature. But how robust are these signals of thermal adaptation to the other ecological challenges that animals commonly face in the wild? Seasonal changes in population density, food availability, or photoperiod are common ecological challenges that could disrupt patterns of thermal tolerance along a cline if each population differentially used these signals to anticipate future temperatures and adjust their thermal tolerances accordingly. In this study, we aimed to test the robustness of a cline in thermal tolerance to simulated signals of seasonal heterogeneity. Experimental animals were derived from clones of the Australian water flea, Daphnia carinata, sampled from nine distinct populations along a latitudinal transect in Eastern Australia. We then factorially combined summer (18 h light, 6 h dark) and winter (6 h light, 18 h dark) photoperiods with high (5 million algal cells individual-1 day-1) and low (1 million algal cells individual-1 day-1) food availabilities, before performing static heat shock assays to measure thermal tolerance. We found that the thermal tolerances of the clonal populations were sensitive to both measures of seasonal change. In general, higher food availability led to an increase in thermal tolerances, with the magnitude of the increase varying by clone. In contrast, a switch in photoperiod led to rank-order changes in thermal tolerances, with heat resistance increasing for some clones, and decreasing for others. Heat resistance, however, still declined with increasing latitude, irrespective of the manipulation of seasonal signals, with clones from northern populations always showing greater thermal resistance, most likely driven by adaptation to winter thermal conditions. While photoperiod and food availability can clearly shape thermal tolerances for specific populations, they are unlikely to overwhelm overarching signals of thermal adaptation, and thus, observed clines in heat resistance will likely have remained robust to these forms of seasonal heterogeneity.
Collapse
Affiliation(s)
- Jared Lush
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Carla M Sgrò
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Matthew D Hall
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| |
Collapse
|
2
|
Santos JL, Ebert D. The limits of stress-tolerance for zooplankton resting stages in freshwater ponds. Oecologia 2023; 203:453-465. [PMID: 37971560 PMCID: PMC10684647 DOI: 10.1007/s00442-023-05478-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 11/06/2023] [Indexed: 11/19/2023]
Abstract
In seasonal environments, many organisms evolve strategies such as diapause to survive stressful periods. Understanding the link between habitat stability and diapause strategy can help predict a population's survival in a changing world. Indeed, resting stages may be an important way freshwater organisms can survive periods of drought or freezing, and as the frequency and extent of drought or freezing vary strongly among habitats and are predicted to change with climate change, it raises questions about how organisms cope with, and survive, environmental stress. Using Daphnia magna as a model system, we tested the ability of resting stages from different populations to cope with stress during diapause. The combination of elevated temperatures and wet conditions during diapause shows to prevent hatching altogether. In contrast, hatching is relatively higher after a dry and warm diapause, but declines with rising temperatures, while time to hatch increases. Resting stages produced by populations from summer-dry habitats perform slightly, but consistently, better at higher temperatures and dryness, supporting the local adaptation hypothesis. A higher trehalose content in resting eggs from summer-dry habitat might explain such pattern. Considering that temperatures and summer droughts are projected to increase in upcoming years, it is fundamental to know how resting stages resist stressful conditions so as to predict and protect the ecological functioning of freshwater ecosystems.
Collapse
Affiliation(s)
- Joana L Santos
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051, Basel, Switzerland.
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051, Basel, Switzerland
| |
Collapse
|
3
|
Ebert D. Daphnia as a versatile model system in ecology and evolution. EvoDevo 2022; 13:16. [PMID: 35941607 PMCID: PMC9360664 DOI: 10.1186/s13227-022-00199-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 06/20/2022] [Indexed: 11/10/2022] Open
Abstract
Water fleas of the genus Daphnia have been a model system for hundreds of years and is among the best studied ecological model organisms to date. Daphnia are planktonic crustaceans with a cyclic parthenogenetic life-cycle. They have a nearly worldwide distribution, inhabiting standing fresh- and brackish water bodies, from small temporary pools to large lakes. Their predominantly asexual reproduction allows for the study of phenotypes excluding genetic variation, enabling us to separate genetic from non-genetic effects. Daphnia are often used in studies related to ecotoxicology, predator-induced defence, host–parasite interactions, phenotypic plasticity and, increasingly, in evolutionary genomics. The most commonly studied species are Daphnia magna and D. pulex, for which a rapidly increasing number of genetic and genomic tools are available. Here, I review current research topics, where the Daphnia model system plays a critical role.
Collapse
Affiliation(s)
- Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, CH-4051, Basel, Switzerland.
| |
Collapse
|
4
|
Barnard-Kubow KB, Becker D, Murray CS, Porter R, Gutierrez G, Erickson P, Nunez JCB, Voss E, Suryamohan K, Ratan A, Beckerman A, Bergland AO. Genetic Variation in Reproductive Investment Across an Ephemerality Gradient in Daphnia pulex. Mol Biol Evol 2022; 39:msac121. [PMID: 35642301 PMCID: PMC9198359 DOI: 10.1093/molbev/msac121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Species across the tree of life can switch between asexual and sexual reproduction. In facultatively sexual species, the ability to switch between reproductive modes is often environmentally dependent and subject to local adaptation. However, the ecological and evolutionary factors that influence the maintenance and turnover of polymorphism associated with facultative sex remain unclear. We studied the ecological and evolutionary dynamics of reproductive investment in the facultatively sexual model species, Daphnia pulex. We found that patterns of clonal diversity, but not genetic diversity varied among ponds consistent with the predicted relationship between ephemerality and clonal structure. Reconstruction of a multi-year pedigree demonstrated the coexistence of clones that differ in their investment into male production. Mapping of quantitative variation in male production using lab-generated and field-collected individuals identified multiple putative quantitative trait loci (QTL) underlying this trait, and we identified a plausible candidate gene. The evolutionary history of these QTL suggests that they are relatively young, and male limitation in this system is a rapidly evolving trait. Our work highlights the dynamic nature of the genetic structure and composition of facultative sex across space and time and suggests that quantitative genetic variation in reproductive strategy can undergo rapid evolutionary turnover.
Collapse
Affiliation(s)
- Karen B Barnard-Kubow
- Department of Biology, University of Virginia, Charlottesville, VA, USA
- Department of Biology, James Madison University, Harrisonburg, VA, USA
| | - Dörthe Becker
- Department of Biology, University of Virginia, Charlottesville, VA, USA
- School of Biosciences, Ecology and Evolutionary Biology, University of Sheffield, Sheffield, UK
- Department of Biology, University of Marburg, Marburg, Germany
| | - Connor S Murray
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Robert Porter
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Grace Gutierrez
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | | | - Joaquin C B Nunez
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Erin Voss
- Department of Biology, University of Virginia, Charlottesville, VA, USA
- Department of Integrative Biology, UC Berkeley, Berkeley, CA, USA
| | | | - Aakrosh Ratan
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
- Department of Public Health Sciences, University of Virginia, Charlottesville, VA, USA
| | - Andrew Beckerman
- School of Biosciences, Ecology and Evolutionary Biology, University of Sheffield, Sheffield, UK
| | - Alan O Bergland
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| |
Collapse
|
5
|
Fields PD, McTaggart S, Reisser CMO, Haag C, Palmer WH, Little TJ, Ebert D, Obbard DJ. Population-genomic analysis identifies a low rate of global adaptive fixation in the proteins of the cyclical parthenogen Daphnia magna. Mol Biol Evol 2022; 39:6542319. [PMID: 35244177 PMCID: PMC8963301 DOI: 10.1093/molbev/msac048] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Daphnia are well-established ecological and evolutionary models, and the interaction between D. magna and its microparasites is widely considered a paragon of the host-parasite coevolutionary process. Like other well-studied arthropods such as Drosophila melanogaster and Anopheles gambiae, D. magna is a small, widespread, and abundant species that is therefore expected to display a large long-term population size and high rates of adaptive protein evolution. However, unlike these other species, D. magna is cyclically asexual and lives in a highly structured environment (ponds and lakes) with moderate levels of dispersal, both of which are predicted to impact upon long-term effective population size and adaptive protein evolution. To investigate patterns of adaptive protein fixation, we produced the complete coding genomes of 36 D. magna clones sampled from across the European range (Western Palaearctic), along with draft sequences for the close relatives D. similis and D. lumholtzi, used as outgroups. We analyzed genome-wide patterns of adaptive fixation, with a particular focus on genes that have an a priori expectation of high rates, such as those likely to mediate immune responses, RNA interference against viruses and transposable elements, and those with a strongly male-biased expression pattern. We find that, as expected, D. magna displays high levels of diversity and that this is highly structured among populations. However, compared with Drosophila, we find that D. magna proteins appear to have a high proportion of weakly deleterious variants and do not show evidence of pervasive adaptive fixation across its entire range. This is true of the genome as a whole, and also of putative ‘arms race’ genes that often show elevated levels of adaptive substitution in other species. In addition to the likely impact of extensive, and previously documented, local adaptation, we speculate that these findings may reflect reduced efficacy of selection associated with cyclical asexual reproduction.
Collapse
Affiliation(s)
- Peter D Fields
- University of Basel, Department of Environmental Sciences, Zoology, Vesalgasse 1, Basel, CH-4051, Switzerland
| | - Seanna McTaggart
- Institute of Evolutionary Biology; School of Biological Sciences University of Edinburgh, Edinburgh, EH9 3JT, United Kingdom
| | - Céline M O Reisser
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE UMR 5175, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, campus CNRS, 1919, route de Mende, 34293 Montpellier Cedex 5, France.,MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
| | - Christoph Haag
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE UMR 5175, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, campus CNRS, 1919, route de Mende, 34293 Montpellier Cedex 5, France
| | - William H Palmer
- Institute of Evolutionary Biology; School of Biological Sciences University of Edinburgh, Edinburgh, EH9 3JT, United Kingdom
| | - Tom J Little
- Institute of Evolutionary Biology; School of Biological Sciences University of Edinburgh, Edinburgh, EH9 3JT, United Kingdom
| | - Dieter Ebert
- University of Basel, Department of Environmental Sciences, Zoology, Vesalgasse 1, Basel, CH-4051, Switzerland
| | - Darren J Obbard
- Institute of Evolutionary Biology; School of Biological Sciences University of Edinburgh, Edinburgh, EH9 3JT, United Kingdom
| |
Collapse
|
6
|
Santos JL, Ebert D. Trehalose provisioning in Daphnia resting stages reflects local adaptation to the harshness of diapause conditions. Biol Lett 2022; 18:20210615. [PMID: 35135311 PMCID: PMC8826299 DOI: 10.1098/rsbl.2021.0615] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Environmental fluctuations often select for adaptations such as diapause states, allowing species to outlive harsh conditions. The natural sugar trehalose which provides both cryo- and desiccation-protection, has been found in diapause stages of diverse taxa. Here, we hypothesize that trehalose deposition in resting stages is a locally adapted trait, with higher concentrations produced in harsher habitats. We used resting stages, produced under standardized conditions, by 37 genotypes of Daphnia magna collected from Western Palaearctic habitats varying in their propensity to dry in summer and freeze in winter. Resting eggs produced by D. magna from populations from summer-dry habitats showed significantly higher trehalose than those from summer-wet habitats, suggesting that trehalose has a protective function during desiccation. By contrast, winter-freezing did not explain variation in trehalose content. Adaptations to droughts are important, as summer dryness of water bodies is foreseen to increase with ongoing climate change.
Collapse
Affiliation(s)
- Joana L. Santos
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland
| |
Collapse
|
7
|
Lever J, Drapes S, Hall MD, Booksmythe I. Condition-dependent sexual reproduction is driven by benefits, not costs of sex. Behav Ecol 2021. [DOI: 10.1093/beheco/arab103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Facultative sexual organisms must allocate resources to both asexual and sexual reproduction. Optimal patterns of investment in sex depend on the relative costs and benefits of each reproductive mode, and may consequently be context- and condition-dependent. Two proposed explanations for the observed variation in investment in sex among facultative sexual lineages invoke alternative condition-dependent scenarios. Under the fitness-associated sex hypothesis, sex is predicted when individuals are in poor condition or experience stressful environments. Under the resource-demanding sex hypothesis, sex is only affordable to individuals in good condition experiencing favourable environments. Direct tests of these contrasting hypotheses are rare; moreover, investment in different components of sexual reproduction responds differently to cues promoting sex, and may be subject to different energetic constraints. Using genotypes of facultative sexual Daphnia carinata that differ in their level of investment in sex, we manipulated resource availability while accounting for day length (a seasonal cue for sex) to evaluate these hypotheses. The sexual response to day length depended on resource availability: increased day lengths and reduced food availability increased the production of sexual eggs, and relative investment in males, in a manner consistent with the fitness-associated sex hypothesis. The pattern of condition-dependence was specific to each component of reproductive investment – while male production covaried with asexual fecundity across genotypes, increased sexual egg production was associated with reduced asexual reproduction. Our results suggest that investment in sex is determined largely by its context-dependent advantages, and that this investment is not moderated by immediate costs to asexual reproduction.
Collapse
Affiliation(s)
- Jessica Lever
- School of Biological Sciences, Monash University, Melbourne, Victoria 3183, Australia
| | - Sally Drapes
- School of BioSciences, Melbourne University, Parkville, Victoria 3010, Australia
| | - Matthew D Hall
- School of Biological Sciences, Monash University, Melbourne, Victoria 3183, Australia
| | - Isobel Booksmythe
- School of Biological Sciences, Monash University, Melbourne, Victoria 3183, Australia
| |
Collapse
|
8
|
Drapes S, Hall MD, Phillips BL. Effect of habitat permanence on life-history: extending the Daphnia model into new climate spaces. Evol Ecol 2021. [DOI: 10.1007/s10682-021-10119-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
9
|
Schwarzenberger A, Handke NH, Romer T, Wacker A. Geographic clines in Daphnia magna's circadian clock gene expression: Local adaptation to photoperiod. ZOOLOGY 2020; 144:125856. [PMID: 33202364 DOI: 10.1016/j.zool.2020.125856] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 10/11/2020] [Accepted: 10/14/2020] [Indexed: 11/28/2022]
Abstract
Nearly all organisms show daily and seasonal physiological and behavioural responses that are necessary for their survival. Often these responses are controlled by the rhythmic activity of an endogenous clock that perceives day length. Day length differs not only between seasons but also along latitudes, with different seasonal day lengths between the north and the south. Both seasonal and latitudinal differences in day length are discussed to be perceived/processed by the endogenous clock. Some species are distributed over a wide range of latitudes; it should be highly adaptive for these species to be able to time physiological responses (e.g. migration behaviour and diapause) according to the organisms' respective photoperiod, i.e. their respective seasonal and latitudinal day length. The mediator of day length is the indoleamine hormone melatonin which is synthesized by melatonin-producing enzymes (AANAT and HIOMT). These enzymes are in turn controlled by an endogenous clock. The ubiquitous aquatic keystone organism Daphnia possess clock and melatonin synthesis genes that are rhythmically expressed over 24hours. We were able to show that the 24-h rhythm of D. magna's clock persists in constant darkness and is thus truly circadian. In one particular photoperiod, all D. magna clones produced a similar melatonin concentration due to a fixed AANAT activity. However, we have demonstrated that clones originating from different latitudes are adapted to their respective photoperiod by showing a geographic cline in clock and downstream melatonin synthesis gene expression. These findings hint at the problem locally adapted organisms face when they are forced to leave their respective photoperiod, e.g. because of climate change-driven range-expansion. If such a species is incapable of adjusting its endogenous clock to an unknown photoperiod, it will likely become extinct.
Collapse
Affiliation(s)
- Anke Schwarzenberger
- University of Konstanz, Limnological Institute, Mainaustr. 252, 78464 Konstanz, Germany.
| | - Natascha H Handke
- University of Konstanz, Limnological Institute, Mainaustr. 252, 78464 Konstanz, Germany
| | - Tina Romer
- University of Konstanz, Limnological Institute, Mainaustr. 252, 78464 Konstanz, Germany
| | - Alexander Wacker
- University of Greifswald, Zoological Institute and Museum, Department of Animal Ecology, Loitzer Str. 26, 17489 Greifswald, Germany
| |
Collapse
|
10
|
Haag KL, Pombert JF, Sun Y, de Albuquerque NRM, Batliner B, Fields P, Lopes TF, Ebert D. Microsporidia with Vertical Transmission Were Likely Shaped by Nonadaptive Processes. Genome Biol Evol 2020; 12:3599-3614. [PMID: 31825473 PMCID: PMC6944219 DOI: 10.1093/gbe/evz270] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/05/2019] [Indexed: 12/14/2022] Open
Abstract
Microsporidia have the leanest genomes among eukaryotes, and their physiological and genomic simplicity has been attributed to their intracellular, obligate parasitic life-style. However, not all microsporidia genomes are small or lean, with the largest dwarfing the smallest ones by at least an order of magnitude. To better understand the evolutionary mechanisms behind this genomic diversification, we explore here two clades of microsporidia with distinct life histories, Ordospora and Hamiltosporidium, parasitizing the same host species, Daphnia magna. Based on seven newly assembled genomes, we show that mixed-mode transmission (the combination of horizontal and vertical transmission), which occurs in Hamiltosporidium, is found to be associated with larger and AT-biased genomes, more genes, and longer intergenic regions, as compared with the exclusively horizontally transmitted Ordospora. Furthermore, the Hamiltosporidium genome assemblies contain a variety of repetitive elements and long segmental duplications. We show that there is an excess of nonsynonymous substitutions in the microsporidia with mixed-mode transmission, which cannot be solely attributed to the lack of recombination, suggesting that bursts of genome size in these microsporidia result primarily from genetic drift. Overall, these findings suggest that the switch from a horizontal-only to a mixed mode of transmission likely produces population bottlenecks in Hamiltosporidium species, therefore reducing the effectiveness of natural selection, and allowing their genomic features to be largely shaped by nonadaptive processes.
Collapse
Affiliation(s)
- Karen L Haag
- Department of Genetics and Post-Graduation Program of Genetics and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | | | - Yukun Sun
- Department of Biology, Illinois Institute of Technology
| | - Nathalia Rammé M de Albuquerque
- Department of Genetics and Post-Graduation Program of Genetics and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | | | - Peter Fields
- Department of Environmental Sciences, Zoology, Basel University, Switzerland
| | - Tiago Falcon Lopes
- Department of Genetics and Post-Graduation Program of Genetics and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, Basel University, Switzerland
| |
Collapse
|
11
|
An alternative route of bacterial infection associated with a novel resistance locus in the Daphnia-Pasteuria host-parasite system. Heredity (Edinb) 2020; 125:173-183. [PMID: 32561843 PMCID: PMC7490384 DOI: 10.1038/s41437-020-0332-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 06/07/2020] [Accepted: 06/07/2020] [Indexed: 11/23/2022] Open
Abstract
To understand the mechanisms of antagonistic coevolution, it is crucial to identify the genetics of parasite resistance. In the Daphnia magna–Pasteuria ramosa host–parasite system, the most important step of the infection process is the one in which P. ramosa spores attach to the host’s foregut. A matching-allele model (MAM) describes the host–parasite genetic interactions underlying attachment success. Here we describe a new P. ramosa genotype, P15, which, unlike previously studied genotypes, attaches to the host’s hindgut, not to its foregut. Host resistance to P15 attachment shows great diversity across natural populations. In contrast to P. ramosa genotypes that use foregut attachment, P15 shows some quantitative variation in attachment success and does not always lead to successful infections, suggesting that hindgut attachment represents a less-efficient infection mechanism than foregut attachment. Using a Quantitative Trait Locus (QTL) approach, we detect two significant QTLs in the host genome: one that co-localizes with the previously described D. magna PR locus of resistance to foregut attachment, and a second, major QTL located in an unlinked genomic region. We find no evidence of epistasis. Fine mapping reveals a genomic region, the D locus, of ~13 kb. The discovery of a second P. ramosa attachment site and of a novel host-resistance locus increases the complexity of this system, with implications for both for the coevolutionary dynamics (e.g., Red Queen and the role of recombination), and for the evolution and epidemiology of the infection process.
Collapse
|
12
|
Czypionka T, Fields PD, Routtu J, van den Berg E, Ebert D, De Meester L. The genetic architecture underlying diapause termination in a planktonic crustacean. Mol Ecol 2019; 28:998-1008. [PMID: 30592346 DOI: 10.1111/mec.15001] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 11/15/2018] [Accepted: 11/27/2018] [Indexed: 01/17/2023]
Abstract
Diapause is a feature of the life cycle of many invertebrates by which unfavourable environmental conditions can be outlived. The seasonal timing of diapause allows organisms to adapt to seasonal changes in habitat suitability and thus is key to their fitness. In the planktonic crustacean Daphnia, various cues can induce the production of diapause stages that are resistant to heat, drought or freezing and contain one to two embryos in developmental arrest. Daphnia is a keystone species of many freshwater ecosystems, where it acts as the main link between phytoplankton and higher trophic levels. The correct seasonal timing of diapause termination is essential to maintain trophic interactions and is achieved via a genetically based interpretation of environmental cues like photoperiod and temperature. Field monitoring and modelling studies raised concerns on whether populations can advance their seasonal release from diapause to advances in spring phenology under global change, or if a failure to adapt will cause trophic mismatches negatively affecting ecosystem functioning. Our capacity to understand and predict the evolution of diapause timing requires information about the genetic architecture underlying this trait. In this study, we identified eight quantitative trait loci (QTLs) and four epistatic interactions that together explained 66.5% of the variation in diapause termination in Daphnia magna using QTL mapping. Our results suggest that the most significant QTL is modulating diapause termination dependent on photoperiod and is involved in three of the four detected epistatic interactions. Candidate genes at this QTL could be identified through the integration with genome data and included the presynaptic active zone protein bruchpilot. Our findings contribute to understanding the genomic control of seasonal diapause timing in an ecological relevant species.
Collapse
Affiliation(s)
- Till Czypionka
- Laboratory of Aquatic Ecology and Evolutionary Biology, KU Leuven, Leuven, Belgium
| | - Peter D Fields
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland
| | - Jarkko Routtu
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland.,Molecular Ecology, Martin-Luther-Universität, Halle-Wittenberg, Germany
| | - Edwin van den Berg
- Laboratory of Aquatic Ecology and Evolutionary Biology, KU Leuven, Leuven, Belgium
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland
| | - Luc De Meester
- Laboratory of Aquatic Ecology and Evolutionary Biology, KU Leuven, Leuven, Belgium
| |
Collapse
|
13
|
Seudre O, Vanhoenacker E, Mauger S, Coudret J, Roze D. Genetic variability and transgenerational regulation of investment in sex in the monogonont rotifer Brachionus plicatilis. J Evol Biol 2019; 33:112-120. [PMID: 31617617 DOI: 10.1111/jeb.13554] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 09/19/2019] [Accepted: 10/10/2019] [Indexed: 11/26/2022]
Abstract
In cyclical parthenogens such as aphids, cladocerans and rotifers, the coupling between sexual reproduction and the production of resting stages (diapausing eggs) imposes strong constraints on the timing of sex. Whereas induction of sex is generally triggered by environmental cues, the response to such cues may vary across individuals according to genetic and nongenetic factors. In this study, we explored genetic and epigenetic causes of variation for the propensity for sex using a collection of strains from a Spanish population of monogonont rotifers (Brachionus plicatilis) in which variation for the threshold population density at which sex is induced (mixis threshold) had been documented previously. Our results show significant variation for the mixis threshold among 20 clones maintained under controlled conditions for 15 asexual generations. The effect of the number of clonal generations since hatching of the diapausing egg on the mixis ratio (proportion of sexual offspring produced) was tested on 4 clones with contrasted mixis thresholds. The results show a negative correlation between the mixis threshold and mixis ratio, as well as a significant effect of the number of clonal generations since fertilization, sex being repressed during the first few generations after hatching of the diapausing egg.
Collapse
Affiliation(s)
- Océane Seudre
- Evolutionary Biology and Ecology of Algae, UMI 3614, CNRS, Roscoff, France.,Sorbonne Université, Station Biologique de Roscoff, Roscoff, France
| | - Eloïse Vanhoenacker
- Evolutionary Biology and Ecology of Algae, UMI 3614, CNRS, Roscoff, France.,Sorbonne Université, Station Biologique de Roscoff, Roscoff, France
| | - Stéphane Mauger
- Evolutionary Biology and Ecology of Algae, UMI 3614, CNRS, Roscoff, France.,Sorbonne Université, Station Biologique de Roscoff, Roscoff, France
| | - Jérôme Coudret
- Evolutionary Biology and Ecology of Algae, UMI 3614, CNRS, Roscoff, France.,Sorbonne Université, Station Biologique de Roscoff, Roscoff, France
| | - Denis Roze
- Evolutionary Biology and Ecology of Algae, UMI 3614, CNRS, Roscoff, France.,Sorbonne Université, Station Biologique de Roscoff, Roscoff, France
| |
Collapse
|
14
|
Hall MD, Mideo N. Linking sex differences to the evolution of infectious disease life-histories. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2017.0431. [PMID: 30150228 DOI: 10.1098/rstb.2017.0431] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2018] [Indexed: 12/23/2022] Open
Abstract
Sex differences in the prevalence, course and severity of infection are widespread, yet the evolutionary consequences of these differences remain unclear. Understanding how male-female differences affect the trajectory of infectious disease requires connecting the contrasting dynamics that pathogens might experience within each sex to the number of susceptible and infected individuals that are circulating in a population. In this study, we build on theory using genetic covariance functions to link the growth of a pathogen within a host to the evolution and spread of disease between individuals. Using the Daphnia-Pasteuria system as a test case, we show that on the basis of within-host dynamics alone, females seem to be more evolutionarily liable for the pathogen, with higher spore loads and greater divergence among pathogen genotypes as infection progresses. Between-host transmission, however, appears to offset the lower performance of a pathogen within a male host, making even subtle differences between the sexes evolutionarily relevant, as long as the selection generated by the between-host dynamics is sufficiently strong. Our model suggests that relatively simple differences in within-host processes occurring in males and females can lead to complex patterns of genetic constraint on pathogen evolution, particularly during an expanding epidemic.This article is part of the theme issue 'Linking local adaptation with the evolution of sex differences'.
Collapse
Affiliation(s)
- Matthew D Hall
- School of Biological Sciences and Centre for Geometric Biology, Monash University, Melbourne, Victoria 3800, Australia
| | - Nicole Mideo
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
15
|
Hartnett R. Variation in life-history traits among Daphnia and its relationship to species-level responses to phosphorus limitation. ROYAL SOCIETY OPEN SCIENCE 2019; 6:191024. [PMID: 31598264 PMCID: PMC6731724 DOI: 10.1098/rsos.191024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 07/17/2019] [Indexed: 05/31/2023]
Abstract
Currently organisms are experiencing changes in their environment at an unprecedented rate. Therefore, the study of the contributions to and responses in traits linked to fitness is crucial, as they have direct consequences on a population's success in persisting under such a change. Daphnia is used as a model organism as the genus contains keystone primary consumers in aquatic food webs. A life-history table experiment (LHTE) using four species of Daphnia was conducted to compare variation in life-history traits among species across two different environmental conditions (high and low phosphorus availability). Results indicate that the food quality environment had the most impact on life-history traits, while genetic contributions to traits were higher at the species-level than clonal-level. Higher trait variation and species-level responses to P-limitation were more evident in reproductive traits, while growth traits were found to be less affected by food quality and had less variation. Exploring trait variation and potential plasticity in organisms is increasingly important to consider as a potential mechanism for population persistence given the fluctuations in environmental stressors we are currently experiencing.
Collapse
|
16
|
Hartnett R. Variation in life-history traits among Daphnia and its relationship to species-level responses to phosphorus limitation. ROYAL SOCIETY OPEN SCIENCE 2019. [PMID: 31598264 DOI: 10.5061/dryad.d4v7g74] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Currently organisms are experiencing changes in their environment at an unprecedented rate. Therefore, the study of the contributions to and responses in traits linked to fitness is crucial, as they have direct consequences on a population's success in persisting under such a change. Daphnia is used as a model organism as the genus contains keystone primary consumers in aquatic food webs. A life-history table experiment (LHTE) using four species of Daphnia was conducted to compare variation in life-history traits among species across two different environmental conditions (high and low phosphorus availability). Results indicate that the food quality environment had the most impact on life-history traits, while genetic contributions to traits were higher at the species-level than clonal-level. Higher trait variation and species-level responses to P-limitation were more evident in reproductive traits, while growth traits were found to be less affected by food quality and had less variation. Exploring trait variation and potential plasticity in organisms is increasingly important to consider as a potential mechanism for population persistence given the fluctuations in environmental stressors we are currently experiencing.
Collapse
Affiliation(s)
- Rachel Hartnett
- Department of Biology, Program in Ecology and Evolutionary Biology, The University of Oklahoma, 730 Van Vleet Oval, Room 314, Norman, OK 73019, USA
| |
Collapse
|
17
|
Hall MD, Routtu J, Ebert D. Dissecting the genetic architecture of a stepwise infection process. Mol Ecol 2019; 28:3942-3957. [PMID: 31283079 DOI: 10.1111/mec.15166] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 06/27/2019] [Accepted: 06/28/2019] [Indexed: 02/06/2023]
Abstract
How a host fights infection depends on an ordered sequence of steps, beginning with attempts to prevent a pathogen from establishing an infection, through to steps that mitigate a pathogen's control of host resources or minimize the damage caused during infection. Yet empirically characterizing the genetic basis of these steps remains challenging. Although each step is likely to have a unique genetic and environmental signature, and may therefore respond to selection in different ways, events that occur earlier in the infection process can mask or overwhelm the contributions of subsequent steps. In this study, we dissect the genetic architecture of a stepwise infection process using a quantitative trait locus (QTL) mapping approach. We control for variation at the first line of defence against a bacterial pathogen and expose downstream genetic variability related to the host's ability to mitigate the damage pathogens cause. In our model, the water-flea Daphnia magna, we found a single major effect QTL, explaining 64% of the variance, that is linked to the host's ability to completely block pathogen entry by preventing their attachment to the host oesophagus; this is consistent with the detection of this locus in previous studies. In susceptible hosts allowing attachment, however, a further 23 QTLs, explaining between 5% and 16% of the variance, were mapped to traits related to the expression of disease. The general lack of pleiotropy and epistasis for traits related to the different stages of the infection process, together with the wide distribution of QTLs across the genome, highlights the modular nature of a host's defence portfolio, and the potential for each different step to evolve independently. We discuss how isolating the genetic basis of individual steps can help to resolve discussion over the genetic architecture of host resistance.
Collapse
Affiliation(s)
- Matthew D Hall
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland.,School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Jarkko Routtu
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland.,Molecular Ecology, Martin-Luther-Universität, Halle-Wittenberg, Germany
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland
| |
Collapse
|
18
|
Seefeldt L, Ebert D. Temperature- versus precipitation-limitation shape local temperature tolerance in a Holarctic freshwater crustacean. Proc Biol Sci 2019; 286:20190929. [PMID: 31337313 PMCID: PMC6661336 DOI: 10.1098/rspb.2019.0929] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Species with wide geographical distributions are often adapted locally to the prevailing temperatures. To understand how they respond to ongoing climatic change, we must appreciate the interplay between temperature, seasonality and the organism's life cycle. The temperature experienced by many organisms results from an often-overlooked combination of climate and phenology. Summer-active (high latitude) populations are expected to adapt to local summer temperatures, but this is not expected for populations that outlive the summer in their dormant stage (low latitude, precipitation-limited). We recorded reproduction and survival in genotypes from 123 Holarctic populations of Daphnia magna during a multi-generation thermal ramp experiment. Genotypes from summer-active populations showed a positive relationship between heat tolerance and local summer temperature, whereas winter-active populations did not. These findings are consistent with the hypothesis that D. magna adapts to the local temperatures the animals experience during their planktonic phase. We conclude that predicting local temperature adaptation, in particular in the light of climate change, needs to consider the phenology of geographically wide-ranging species.
Collapse
Affiliation(s)
- Leonie Seefeldt
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland
| |
Collapse
|
19
|
Abstract
Daphnia normally reproduce by cyclical parthenogenesis, with offspring sex being determined by environmental cues. However, some females have lost the ability to produce males. Our results demonstrate that this loss of male-producing ability is controlled by a dominant allele at a single locus. We identified the locus by comparing whole-genome sequences of 67 nonmale-producing (NMP) and 100 male-producing (MP) clones from 5 Daphnia pulex populations, revealing 132 NMP-linked SNPs and 59 NMP-linked indels within a single 1.1-Mb nonrecombining region on chromosome I. These markers include 7 nonsynonymous mutations, all of which are located within one unannotated protein-coding gene (gene 8960). Within this single gene, all of the marker-linked NMP haplotypes from different populations form a monophyletic clade, suggesting a single origin of the NMP phenotype, with the NMP haplotype originating by introgression from a sister species, Daphnia pulicaria Methyl farnesoate (MF) is the innate juvenile hormone in daphnids, which induces the production of males and whose inhibition results in female-only production. Gene 8960 is sensitive to treatment by MF in MP clones, but such responsiveness is greatly reduced in NMP clones. Thus, we hypothesize that gene 8960 is located downstream of the MF-signaling pathway in D. pulex, with the NMP phenotype being caused by expression change of gene 8960.
Collapse
|
20
|
Molinier C, Reisser CMO, Fields PD, Ségard A, Galimov Y, Haag CR. Evolution of Gene Expression during a Transition from Environmental to Genetic Sex Determination. Mol Biol Evol 2019; 36:1551-1564. [PMID: 31173134 DOI: 10.1093/molbev/msz123] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Genetic sex determination (GSD) can evolve from environmental sex determination (ESD) via an intermediate state in which both coexist in the same population. Such mixed populations are found in the crustacean Daphnia magna, where non-male producers (NMP, genetically determined females) coexist with male producers (MP), in which male production is environmentally inducible and can also artificially be triggered by exposure to juvenile hormone. This makes Daphnia magna a rare model species for the study of evolutionary transitions from ESD to GSD. Although the chromosomal location of the NMP-determining mutation has been mapped, the actual genes and pathways involved in the evolution of GSD from ESD remain unknown. Here, we present a transcriptomic analysis of MP and NMP females under control (female producing) and under hormone exposure conditions. We found ∼100 differentially expressed genes between MP and NMP under control conditions. Genes in the NMP-determining chromosome region were especially likely to show such constitutive expression differences. Hormone exposure led to expression changes of an additional ∼100 (MP) to ∼600 (NMP) genes, with an almost systematic upregulation of those genes in NMP. These observations suggest that the NMP phenotype is not determined by a simple "loss-of-function" mutation. Rather, homeostasis of female offspring production under hormone exposure appears to be an active state, tightly regulated by complex mechanisms involving many genes. In a broader view, this illustrates that the evolution of GSD, while potentially initiated by a single mutation, likely leads to secondary integration involving many genes and pathways.
Collapse
Affiliation(s)
- Cécile Molinier
- CEFE, CNRS, Univ Montpellier, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| | - Céline M O Reisser
- CEFE, CNRS, Univ Montpellier, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France.,Université de Fribourg, Ecology and Evolution, Fribourg, Switzerland.,IFREMER Centre du Pacifique, UMR 241 EIO, Labex CORAIL, Taravao, Tahiti, Polynésie Française
| | - Peter D Fields
- Universität Basel, Zoology Institute, Evolutionary Biology, Basel, Switzerland
| | - Adeline Ségard
- CEFE, CNRS, Univ Montpellier, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| | - Yan Galimov
- Koltsov Institute of Developmental Biology, RAS, Moscow, Russia
| | - Christoph R Haag
- CEFE, CNRS, Univ Montpellier, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France.,Université de Fribourg, Ecology and Evolution, Fribourg, Switzerland
| |
Collapse
|
21
|
Nørgaard LS, Phillips BL, Hall MD. Can pathogens optimize both transmission and dispersal by exploiting sexual dimorphism in their hosts? Biol Lett 2019; 15:20190180. [PMID: 31213141 DOI: 10.1098/rsbl.2019.0180] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Pathogens often rely on their host for dispersal. Yet, maximizing fitness via replication can cause damage to the host and an associated reduction in host movement, incurring a trade-off between transmission and dispersal. Here, we test the idea that pathogens might mitigate this trade-off between reproductive fitness and dispersal by taking advantage of sexual dimorphism in their host, tailoring responses separately to males and females. Using experimental populations of Daphnia magna and its bacterial pathogen Pasteuria ramosa as a test-case, we find evidence that this pathogen can use male hosts as a dispersal vector, and the larger females as high-quality resource patches for optimized production of transmission spores. As sexual dimorphism in dispersal and body size is widespread across the animal kingdom, this differential exploitation of the sexes by a pathogen might be an unappreciated phenomenon, possibly evolved in various systems.
Collapse
Affiliation(s)
- Louise Solveig Nørgaard
- 1 School of Biological Sciences, Centre for Geometric Biology, Monash University , Melbourne 3800 , Australia
| | - Ben L Phillips
- 2 Department of Biosciences, University of Melbourne , 3010 Parkville, Victoria , Australia
| | - Matthew D Hall
- 1 School of Biological Sciences, Centre for Geometric Biology, Monash University , Melbourne 3800 , Australia
| |
Collapse
|
22
|
Mitogenome phylogeographic analysis of a planktonic crustacean. Mol Phylogenet Evol 2018; 129:138-148. [DOI: 10.1016/j.ympev.2018.06.028] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 06/14/2018] [Accepted: 06/15/2018] [Indexed: 11/17/2022]
|
23
|
Gerber N, Booksmythe I, Kokko H. Sex Allocation Theory for Facultatively Sexual Organisms Inhabiting Seasonal Environments: The Importance of Bet Hedging. Am Nat 2018; 192:155-170. [PMID: 30016165 DOI: 10.1086/697727] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Adaptive explanations for dormancy often invoke bet hedging, where reduced mean fitness can be adaptive if it associates with reduced fitness variance. Sex allocation theory typically ignores variance effects and focuses on mean fitness. For many cyclical parthenogens, these themes become linked, as only sexually produced eggs undergo the dormancy needed to survive harsh conditions. We ask how sex allocation and the timing of sex evolve when this constraint exists in the form of a trade-off between asexual reproduction and sexual production of dormant eggs-the former being crucial for within-season success and the latter for survival across seasons. We show that male production can be temporally separated from or co-occur with sex, depending on whether direct (time) or indirect (population density) cues of the season's end are available and whether population growth is density dependent. Sex generally occurs late in the season but is induced earlier in unpredictable environments. When only indirect cues are available, the temporal spread of sex, and with it the production of dormant stages, is even larger and, given sufficient mortality, leads to endogenous population cycles in which frequent sex coincides with high densities. In all scenarios, algorithms maximizing geometric mean fitness have reduced fitness variance compared with a hypothetical non-bet hedger, confirming that the timing of male production and sex in facultative seasonal settings can be bet-hedging traits.
Collapse
|
24
|
Molinier C, Reisser CMO, Fields P, Ségard A, Galimov Y, Haag CR. Identification of General Patterns of Sex-Biased Expression in Daphnia, a Genus with Environmental Sex Determination. G3 (BETHESDA, MD.) 2018; 8:1523-1533. [PMID: 29535148 PMCID: PMC5940145 DOI: 10.1534/g3.118.200174] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 02/25/2018] [Indexed: 12/18/2022]
Abstract
Daphnia reproduce by cyclic-parthenogenesis, where phases of asexual reproduction are intermitted by sexual production of diapause stages. This life cycle, together with environmental sex determination, allow the comparison of gene expression between genetically identical males and females. We investigated gene expression differences between males and females in four genotypes of Daphnia magna and compared the results with published data on sex-biased gene expression in two other Daphnia species, each representing one of the major phylogenetic clades within the genus. We found that 42% of all annotated genes showed sex-biased expression in D. magna This proportion is similar both to estimates from other Daphnia species as well as from species with genetic sex determination, suggesting that sex-biased expression is not reduced under environmental sex determination. Among 7453 single copy, one-to-one orthologs in the three Daphnia species, 707 consistently showed sex-biased expression and 675 were biased in the same direction in all three species. Hence these genes represent a core-set of genes with consistent sex-differential expression in the genus. A functional analysis identified that several of them are involved in known sex determination pathways. Moreover, 75% were overexpressed in females rather than males, a pattern that appears to be a general feature of sex-biased gene expression in Daphnia.
Collapse
Affiliation(s)
- Cécile Molinier
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)- Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), 1919 Route de Mende, 34293 Montpellier Cedex 5, France
| | - Céline M O Reisser
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)- Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), 1919 Route de Mende, 34293 Montpellier Cedex 5, France
- Université de Fribourg, Ecology and Evolution, Ch. du Musée 10, 1700 Fribourg, Switzerland
- IFREMER Centre du Pacifique, UMR 241 EIO, Labex CORAIL, BP 49, 98719 Taravao, Tahiti, Polynésie Française
| | - Peter Fields
- Universität Basel, Zoology Institute, Evolutionary Biology, Vesalgasse 1, 4051 Basel, Switzerland
| | - Adeline Ségard
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)- Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), 1919 Route de Mende, 34293 Montpellier Cedex 5, France
| | - Yan Galimov
- Koltsov Institute of Developmental Biology RAS ul. Vavilova 26, 119334 Moscow, Russia
| | - Christoph R Haag
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)- Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), 1919 Route de Mende, 34293 Montpellier Cedex 5, France
- Université de Fribourg, Ecology and Evolution, Ch. du Musée 10, 1700 Fribourg, Switzerland
| |
Collapse
|
25
|
Ringot G, Gasparini J, Wagner M, Cheikh Albassatneh M, Frantz A. More and smaller resting eggs along a gradient for pollution by metals: dispersal, dormancy and detoxification strategies in Daphnia? Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/bly026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Gabrielle Ringot
- Sorbonne Universités, Université Paris Diderot, Université Paris-Est Créteil, CNRS, INRA, IRD, Institute of Ecology and Environmental Science – Paris (iEES-Paris), Campus Pierre et Marie Curie, 4 place Jussieu, Paris, France
| | - Julien Gasparini
- Sorbonne Universités, Université Paris Diderot, Université Paris-Est Créteil, CNRS, INRA, IRD, Institute of Ecology and Environmental Science – Paris (iEES-Paris), Campus Pierre et Marie Curie, 4 place Jussieu, Paris, France
| | - Marie Wagner
- Sorbonne Universités, Université Paris Diderot, Université Paris-Est Créteil, CNRS, INRA, IRD, Institute of Ecology and Environmental Science – Paris (iEES-Paris), Campus Pierre et Marie Curie, 4 place Jussieu, Paris, France
| | - Marwan Cheikh Albassatneh
- Sorbonne Universités, Université Paris Diderot, Université Paris-Est Créteil, CNRS, INRA, IRD, Institute of Ecology and Environmental Science – Paris (iEES-Paris), Campus Pierre et Marie Curie, 4 place Jussieu, Paris, France
| | - Adrien Frantz
- Sorbonne Universités, Université Paris Diderot, Université Paris-Est Créteil, CNRS, INRA, IRD, Institute of Ecology and Environmental Science – Paris (iEES-Paris), Campus Pierre et Marie Curie, 4 place Jussieu, Paris, France
| |
Collapse
|
26
|
Booksmythe I, Gerber N, Ebert D, Kokko H. Daphnia females adjust sex allocation in response to current sex ratio and density. Ecol Lett 2018; 21:629-637. [PMID: 29484799 DOI: 10.1111/ele.12929] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 11/19/2017] [Accepted: 01/27/2018] [Indexed: 02/02/2023]
Abstract
Cyclical parthenogenesis presents an interesting challenge for the study of sex allocation, as individuals' allocation decisions involve both the choice between sexual and asexual reproduction, and the choice between sons and daughters. Male production is therefore expected to depend on ecological and evolutionary drivers of overall investment in sex, and those influencing male reproductive value during sexual periods. We manipulated experimental populations, and made repeated observations of natural populations over their growing season, to disentangle effects of population density and the timing of sex from effects of adult sex ratio on sex allocation in cyclically parthenogenetic Daphnia magna. Male production increased with population density, the major ecological driver of sexual reproduction; however, this response was dampened when the population sex ratio was more male-biased. Thus, in line with sex ratio theory, we show that D. magna adjust offspring sex allocation in response to the current population sex ratio.
Collapse
Affiliation(s)
- Isobel Booksmythe
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland.,Tvärminne Zoological Station, J.A. Palmenintie 260, 10900, Hanko, Finland
| | - Nina Gerber
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland.,Tvärminne Zoological Station, J.A. Palmenintie 260, 10900, Hanko, Finland.,Centre of Excellence in Biological Interactions, Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
| | - Dieter Ebert
- Tvärminne Zoological Station, J.A. Palmenintie 260, 10900, Hanko, Finland.,Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, Basel, Switzerland
| | - Hanna Kokko
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| |
Collapse
|
27
|
Gerber N, Kokko H, Ebert D, Booksmythe I. Daphnia invest in sexual reproduction when its relative costs are reduced. Proc Biol Sci 2018; 285:20172176. [PMID: 29343596 PMCID: PMC5805931 DOI: 10.1098/rspb.2017.2176] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 12/11/2017] [Indexed: 11/12/2022] Open
Abstract
The timing of sex in facultatively sexual organisms is critical to fitness, due to the differing demographic consequences of sexual versus asexual reproduction. In addition to the costs of sex itself, an association of sex with the production of dormant life stages also influences the optimal use of sex, especially in environments where resting eggs are essential to survive unfavourable conditions. Here we document population dynamics and the occurrence of sexual reproduction in natural populations of Daphnia magna across their growing season. The frequency of sexually reproducing females and males increased with population density and with decreasing asexual clutch sizes. The frequency of sexually reproducing females additionally increased as population growth rates decreased. Consistent with population dynamic models showing that the opportunity cost of sexual reproduction (foregoing contribution to current population growth) diminishes as populations approach carrying capacity, we found that investment in sexual reproduction was highest when asexual population growth was low or negative. Our results support the idea that the timing of sex is linked with periods when the relative cost of sex is reduced due to low potential asexual growth at high population densities. Thus, a combination of ecological and demographic factors affect the optimal timing of sexual reproduction, allowing D. magna to balance the necessity of sex against its costs.
Collapse
Affiliation(s)
- Nina Gerber
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
- Centre of Excellence in Biological Interactions, Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
- Tvärminne Zoological Station, J.A. Palmenintie 260, 10900 Hanko, Finland
| | - Hanna Kokko
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Dieter Ebert
- Tvärminne Zoological Station, J.A. Palmenintie 260, 10900 Hanko, Finland
- Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland
| | - Isobel Booksmythe
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
- Tvärminne Zoological Station, J.A. Palmenintie 260, 10900 Hanko, Finland
| |
Collapse
|
28
|
Franch-Gras L, García-Roger EM, Serra M, José Carmona M. Adaptation in response to environmental unpredictability. Proc Biol Sci 2017; 284:20170427. [PMID: 29212717 PMCID: PMC5740265 DOI: 10.1098/rspb.2017.0427] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 11/02/2017] [Indexed: 11/12/2022] Open
Abstract
Understanding how organisms adaptively respond to environmental fluctuations is a fundamental question in evolutionary biology. The Mediterranean region typically exhibits levels of environmental unpredictability that vary greatly in habitats over small geographical scales. In cyclically parthenogenetic rotifers, clonal proliferation occurs along with occasional bouts of sex. These bouts contribute to the production of diapausing eggs, which allows survival between growing seasons. Here, we studied two diapause-related traits in rotifers using clones from nine Brachionus plicatilis natural populations that vary in the degree of environmental unpredictability. We tested the hypothesis that the level of environmental unpredictability is directly related to the propensity for sex and inversely related to the hatching fraction of diapausing eggs. We found significant levels of genetic variation within populations for both traits. Interestingly, a positive correlation between pond unpredictability-quantified in a previous study from satellite imagery-and the propensity for sex was found. This correlation suggests a conservative, bet-hedging strategy that provides protection against unexpectedly short growing seasons. By contrast, the hatching fraction of diapausing eggs was not related to the level of environmental predictability. Our results highlight the ability of rotifer populations to locally adapt to time-varying environments, providing an evolutionarily relevant step forward in relating life-history traits to a quantitative measure of environmental unpredictability.
Collapse
Affiliation(s)
- Lluis Franch-Gras
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, A.O. 22085, 46071 Valencia, Spain
| | - Eduardo M García-Roger
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, A.O. 22085, 46071 Valencia, Spain
| | - Manuel Serra
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, A.O. 22085, 46071 Valencia, Spain
| | - María José Carmona
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, A.O. 22085, 46071 Valencia, Spain
| |
Collapse
|
29
|
QTL mapping of a natural genetic polymorphism for long-term parasite persistence in Daphnia populations. Parasitology 2017; 144:1686-1694. [DOI: 10.1017/s0031182017001032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SUMMARYKnowing the determinants of the geographic ranges of parasites is important for understanding their evolutionary ecology, epidemiology and their potential to expand their range. Here we explore the determinants of geographic range in the peculiar case of a parasite species – the microsporidian Hamiltosporidium tvaerminnensis – that has a limited geographic distribution in a wide-spread host – Daphnia magna. We conducted a quantitative trait loci (QTLs) analysis with monoclonal F2D. magna populations originating from a cross between a susceptible northern European genotype and a resistant central European genotype. Contrary to our expectations, long-term persistence turned out to be a quantitative trait across the F2 offspring. Evidence for two QTLs, one epistatic interaction and for further minor QTL was found. This finding contrasts markedly with the previously described bimodal pattern for long-term parasite persistence in natural host genotypes across Europe and leaves open the question of how a quantitative genetic trait could determine the disjunct geographic distribution of the parasite across Europe.
Collapse
|
30
|
Reisser CMO, Fasel D, Hürlimann E, Dukic M, Haag-Liautard C, Thuillier V, Galimov Y, Haag CR. Transition from Environmental to Partial Genetic Sex Determination in Daphnia through the Evolution of a Female-Determining Incipient W Chromosome. Mol Biol Evol 2017; 34:575-588. [PMID: 28007974 DOI: 10.1093/molbev/msw251] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Sex chromosomes can evolve during the evolution of genetic sex determination (GSD) from environmental sex determination (ESD). Despite theoretical attention, early mechanisms involved in the transition from ESD to GSD have yet to be studied in nature. No mixed ESD-GSD animal species have been reported, except for some species of Daphnia, small freshwater crustaceans in which sex is usually determined solely by the environment, but in which a dominant female sex-determining locus is present in some populations. This locus follows Mendelian single-locus inheritance, but has otherwise not been characterized genetically. We now show that the sex-determining genomic region maps to the same low-recombining peri-centromeric region of linkage group 3 (LG3) in three highly divergent populations of D. magna, and spans 3.6 Mb. Despite low levels of recombination, the associated region contains signs of historical recombination, suggesting a role for selection acting on several genes thereby maintaining linkage disequilibrium among the 36 associated SNPs. The region carries numerous genes involved in sex differentiation in other taxa, including transformer2 and sox9. Taken together, the region determining the genetic females shows characteristics of a sex-related supergene, suggesting that LG3 is potentially an incipient W chromosome despite the lack of significant additional restriction of recombination between Z and W. The occurrence of the female-determining locus in a pre-existing low recombining region illustrates one possible form of recombination suppression in sex chromosomes. D. magna is a promising model for studying the evolutionary transitions from ESD to GSD and early sex chromosome evolution.
Collapse
Affiliation(s)
- Céline M O Reisser
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE UMR 5175, CNRS Université de Montpellier Université Paul-Valéry Montpellier EPHE, Montpellier, France.,Université de Fribourg, Ecology and Evolution, Fribourg, Switzerland.,IFREMER Centre du Pacifique, Taravao, Tahiti, Polynésie Française
| | - Dominique Fasel
- Université de Fribourg, Ecology and Evolution, Fribourg, Switzerland
| | - Evelin Hürlimann
- Université de Fribourg, Ecology and Evolution, Fribourg, Switzerland
| | - Marinela Dukic
- Universität Basel, Zoology Institute, Evolutionary Biology, Basel, Switzerland
| | | | | | - Yan Galimov
- Koltsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - Christoph R Haag
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE UMR 5175, CNRS Université de Montpellier Université Paul-Valéry Montpellier EPHE, Montpellier, France.,Université de Fribourg, Ecology and Evolution, Fribourg, Switzerland
| |
Collapse
|
31
|
Bourgeois Y, Roulin AC, Müller K, Ebert D. Parasitism drives host genome evolution: Insights from thePasteuria ramosa-Daphnia magnasystem. Evolution 2017; 71:1106-1113. [DOI: 10.1111/evo.13209] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 02/16/2017] [Indexed: 01/14/2023]
Affiliation(s)
- Yann Bourgeois
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
| | - Anne C. Roulin
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
- Institute of Plant and Microbial Biology; Zollikerstrasse 107 8008 Zürich Switzerland
| | - Kristina Müller
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
| | - Dieter Ebert
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
| |
Collapse
|
32
|
Baumgartner MF, Tarrant AM. The Physiology and Ecology of Diapause in Marine Copepods. ANNUAL REVIEW OF MARINE SCIENCE 2017; 9:387-411. [PMID: 27814030 DOI: 10.1146/annurev-marine-010816-060505] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Diapause is a type of dormancy that requires preparation, typically precedes the onset of unfavorable conditions, and necessitates a period of arrest before development can proceed. Two ecologically important groups of copepods have incorporated diapausing stages into their life histories. In freshwater, estuarine, and coastal environments, species within the Centropagoidea superfamily can produce resting eggs containing embryos that may be quiescent, diapausing, or in some intermediate state. Resting eggs sink into the sediments, remain viable over months to years, and form a reservoir from which the planktonic population is reestablished. In coastal and oceanic environments, copepods within the Calanidae and Eucalanidae families can enter diapause during late juvenile (copepodid) or adult stages. These copepods accumulate large amounts of lipids before they migrate into deep water and diapause for several months. Through respiration, diapausing copepods may sequester more carbon in the deep ocean than any other biogeochemical process, and changes in diapause phenology associated with climate change (particularly reduction in diapause duration) could have a significant impact not only on regional ecosystems, but on global climate as well.
Collapse
Affiliation(s)
- Mark F Baumgartner
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543; ,
| | - Ann M Tarrant
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543; ,
| |
Collapse
|
33
|
Dukić M, Berner D, Roesti M, Haag CR, Ebert D. A high-density genetic map reveals variation in recombination rate across the genome of Daphnia magna. BMC Genet 2016; 17:137. [PMID: 27737627 PMCID: PMC5064971 DOI: 10.1186/s12863-016-0445-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 10/04/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Recombination rate is an essential parameter for many genetic analyses. Recombination rates are highly variable across species, populations, individuals and different genomic regions. Due to the profound influence that recombination can have on intraspecific diversity and interspecific divergence, characterization of recombination rate variation emerges as a key resource for population genomic studies and emphasises the importance of high-density genetic maps as tools for studying genome biology. Here we present such a high-density genetic map for Daphnia magna, and analyse patterns of recombination rate across the genome. RESULTS A F2 intercross panel was genotyped by Restriction-site Associated DNA sequencing to construct the third-generation linkage map of D. magna. The resulting high-density map included 4037 markers covering 813 scaffolds and contigs that sum up to 77 % of the currently available genome draft sequence (v2.4) and 55 % of the estimated genome size (238 Mb). Total genetic length of the map presented here is 1614.5 cM and the genome-wide recombination rate is estimated to 6.78 cM/Mb. Merging genetic and physical information we consistently found that recombination rate estimates are high towards the peripheral parts of the chromosomes, while chromosome centres, harbouring centromeres in D. magna, show very low recombination rate estimates. CONCLUSIONS Due to its high-density, the third-generation linkage map for D. magna can be coupled with the draft genome assembly, providing an essential tool for genome investigation in this model organism. Thus, our linkage map can be used for the on-going improvements of the genome assembly, but more importantly, it has enabled us to characterize variation in recombination rate across the genome of D. magna for the first time. These new insights can provide a valuable assistance in future studies of the genome evolution, mapping of quantitative traits and population genetic studies.
Collapse
Affiliation(s)
- Marinela Dukić
- University of Basel, Zoological Institute, Vesalgasse 1, Basel, CH-4051, Switzerland.
| | - Daniel Berner
- University of Basel, Zoological Institute, Vesalgasse 1, Basel, CH-4051, Switzerland
| | - Marius Roesti
- University of Basel, Zoological Institute, Vesalgasse 1, Basel, CH-4051, Switzerland.,Biodiversity Research Centre and Zoology Department, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Christoph R Haag
- Centre d'Ecologie Fonctionnelle et Evolutive - CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE, campus CNRS, 1919, route de Mende, 34293, Montpellier Cedex 5, France.,Department of Biology, Ecology and Evolution, University of Fribourg, Chemin du Muśee 10, 1700, Fribourg, Switzerland
| | - Dieter Ebert
- University of Basel, Zoological Institute, Vesalgasse 1, Basel, CH-4051, Switzerland
| |
Collapse
|
34
|
Zhang YN, Zhu XY, Wang WP, Wang Y, Wang L, Xu XX, Zhang K, Deng DG. Reproductive switching analysis of Daphnia similoides between sexual female and parthenogenetic female by transcriptome comparison. Sci Rep 2016; 6:34241. [PMID: 27671106 PMCID: PMC5037449 DOI: 10.1038/srep34241] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 09/06/2016] [Indexed: 11/09/2022] Open
Abstract
The water flea Daphnia are planktonic crustaceans commonly found in freshwater environment that can switch their reproduction mode from parthenogenesis to sexual reproduction to adapt to the external environment. As such, Daphnia are great model organisms to study the mechanism of reproductive switching, the underlying mechanism of reproduction and development in cladocerans and other animals. However, little is known about the Daphnia's reproductive behaviour at a molecular level. We constructed a genetic database of the genes expressed in a sexual female (SF) and a parthenogenetic female (PF) of D. similoides using Illumina HiSeq 2500. A total of 1,763 differentially expressed genes (865 up- and 898 down-regulated) were detected in SF. Of the top 30 up-regulated SF unigenes, the top 4 unigenes belonged to the Chitin_bind_4 family. In contrast, of the top down-regulated SF unigenes, the top 3 unigenes belonged to the Vitellogenin_N family. This is the first study to indicate genes that may have a crucial role in reproductive switching of D. similoides, which could be used as candidate genes for further functional studies. Thus, this study provides a rich resource for investigation and elucidation of reproductive switching in D. similoides.
Collapse
Affiliation(s)
- Ya-Nan Zhang
- College of Life Sciences, Huaibei Normal University, Huaibei, China
| | - Xiu-Yun Zhu
- College of Life Sciences, Huaibei Normal University, Huaibei, China
| | - Wen-Ping Wang
- College of Life Sciences, Huaibei Normal University, Huaibei, China
| | - Yi Wang
- College of Life Sciences, Huaibei Normal University, Huaibei, China
| | - Lu Wang
- College of Life Sciences, Huaibei Normal University, Huaibei, China
| | - Xiao-Xue Xu
- College of Life Sciences, Huaibei Normal University, Huaibei, China
| | - Kun Zhang
- College of Life Sciences, Huaibei Normal University, Huaibei, China
| | - Dao-Gui Deng
- College of Life Sciences, Huaibei Normal University, Huaibei, China
| |
Collapse
|
35
|
Roulin AC, Bourgeois Y, Stiefel U, Walser JC, Ebert D. A Photoreceptor Contributes to the Natural Variation of Diapause Induction inDaphnia magna. Mol Biol Evol 2016; 33:3194-3204. [DOI: 10.1093/molbev/msw200] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
36
|
Arbore R, Andras JP, Routtu J, Ebert D. Ecological genetics of sediment browsing behaviour in a planktonic crustacean. J Evol Biol 2016; 29:1999-2009. [PMID: 27329766 DOI: 10.1111/jeb.12923] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 05/30/2016] [Accepted: 06/15/2016] [Indexed: 02/03/2023]
Abstract
Zooplankton can display complex habitat selection behaviours that influence the way they interact with their environments. Some species, although primarily pelagic, can exploit sediment-borne particles as a food source or use sediments as a refuge from pelagic predation. However, this strategy may increase the exposure to other risks such as benthic predation and infection from sediment-borne parasite transmission stages. The evolution of habitat selection behaviour in these species is thus expected to be influenced by multiple and possibly contrasting selective forces. Here, we study the browsing behaviour of the water flea Daphnia magna on bottom sediments. First, we demonstrated genetic variation for sediment browsing among D. magna genotypes from natural populations sampled across a broad geographic range. Next, we used an F2 recombinant panel to perform a QTL analysis and identified three regions in the D. magna genome contributing to variation in browsing behaviour. We also analysed the correlation between our data and previously published data on the phototactic behaviour of genotypes from the same F2 panel. Clonal means of the two behavioral traits were not correlated, suggesting that they may evolve independently. Browsing behaviour is likely to be a relevant component of habitat selection in D. magna, and its study may help to incorporate the interactions with the sediment into eco-evolutionary models of this key freshwater species.
Collapse
Affiliation(s)
- R Arbore
- Department of Environmental Sciences, Zoological Institute, University of Basel, Basel, Switzerland.
| | - J P Andras
- Department of Environmental Sciences, Zoological Institute, University of Basel, Basel, Switzerland.,Department of Biological Sciences, Mount Holyoke College, South Hadley, MA, USA
| | - J Routtu
- Department of Environmental Sciences, Zoological Institute, University of Basel, Basel, Switzerland.,Department of Molecular Ecology, Institute of Biology, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - D Ebert
- Department of Environmental Sciences, Zoological Institute, University of Basel, Basel, Switzerland
| |
Collapse
|
37
|
Roulin AC, Mariadassou M, Hall MD, Walser JC, Haag C, Ebert D. High genetic variation in resting-stage production in a metapopulation: Is there evidence for local adaptation? Evolution 2015; 69:2747-56. [DOI: 10.1111/evo.12770] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 07/20/2015] [Accepted: 08/20/2015] [Indexed: 12/23/2022]
Affiliation(s)
- Anne C. Roulin
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
- Institute of Plant Biology; University of Zurich; Zollikerstrasse 107 8008 Zurich Switzerland
| | | | - Matthew D. Hall
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
- School of Biological Sciences; Monash University; Melbourne 3800 Australia
| | - Jean-Claude Walser
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
- Genetic Diversity Centre; Universitätstrasse 16, CHN E 55 8092 Zürich Switzerland
| | - Christoph Haag
- CNRS-UMR5175 CEFE; 1919, Route de Mende 34293 Montpellier France
| | - Dieter Ebert
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
- Tvärminne Zoological Station; Helsinki University; Hanko Finland
| |
Collapse
|
38
|
Lange B, Kaufmann AP, Ebert D. Genetic, ecological and geographic covariables explaining host range and specificity of a microsporidian parasite. J Anim Ecol 2015; 84:1711-9. [DOI: 10.1111/1365-2656.12421] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 05/24/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Benjamin Lange
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
| | - Andrea Patricia Kaufmann
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
- Tvärminne Zoological Station; Hanko FI-10900 Finland
| | - Dieter Ebert
- Zoological Institute; Basel University; Vesalgasse 1 4051 Basel Switzerland
- Tvärminne Zoological Station; Hanko FI-10900 Finland
| |
Collapse
|
39
|
Fields PD, Reisser C, Dukić M, Haag CR, Ebert D. Genes mirror geography inDaphnia magna. Mol Ecol 2015; 24:4521-36. [DOI: 10.1111/mec.13324] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2015] [Revised: 07/13/2015] [Accepted: 07/14/2015] [Indexed: 02/06/2023]
Affiliation(s)
- Peter D. Fields
- Zoological Institute; University of Basel; Vesalgasse 1 Basel CH-4051 Switzerland
| | - Céline Reisser
- Centre d'Ecologie Fonctionnelle et Evolutive - UMR 5175; campus CNRS 1919 route de Mende 34293 Montpellier Cedex 5 France
- Department of Biology; Ecology and Evolution; University of Fribourg; Chemin du Muśee 10 1700 Fribourg Switzerland
| | - Marinela Dukić
- Zoological Institute; University of Basel; Vesalgasse 1 Basel CH-4051 Switzerland
| | - Christoph R. Haag
- Centre d'Ecologie Fonctionnelle et Evolutive - UMR 5175; campus CNRS 1919 route de Mende 34293 Montpellier Cedex 5 France
- Department of Biology; Ecology and Evolution; University of Fribourg; Chemin du Muśee 10 1700 Fribourg Switzerland
| | - Dieter Ebert
- Zoological Institute; University of Basel; Vesalgasse 1 Basel CH-4051 Switzerland
| |
Collapse
|
40
|
Aránguiz-Acuña A, Ramos-Jiliberto R, Serra M. Zooplankton competition promotes trade-offs affecting diapause in rotifers. Oecologia 2014; 177:273-9. [PMID: 25464990 DOI: 10.1007/s00442-014-3172-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 11/23/2014] [Indexed: 11/26/2022]
Abstract
Facultative diapause should be favoured by natural selection in temporary variable habitats. Diapause patterns are evolutionary constrained because producing diapause is resource demanding, which might have implications for competitive dynamics and competitor coexistence through mechanisms such as the storage effect. Besides these implications, competition intensity might affect the quality of the diapausing stages and the reproductive success of the offspring emerging from them. We experimentally analysed traits involved in diapause in the cyclically parthenogenetic rotifer Brachionus calyciflorus, in relation to the presence of its competitor, the cladoceran Moina micrura. Under competition with Moina, Brachionus produced fewer diapausing eggs, most of which possessed visual attributes indicating a higher quality. These diapausing eggs produced under a competitive environment had a higher hatching success; however, the hatchlings exhibited a lower population growth rate. We propose the existence of trade-offs between traits related to diapause: the number of produced eggs, quality of these eggs and hatchling performance. Our results show that interspecific competition may cause fine-tuned changes in the life cycle patterns of the populations. Furthermore, these changes could affect that abundance and performance of competitors and thereby drive back effects on the competitive output. These diapause-driven feedback mechanisms may have strong implications for the dynamics of the natural communities.
Collapse
Affiliation(s)
- Adriana Aránguiz-Acuña
- Facultad de Ciencias, Departamento de Química, Universidad Católica del Norte, Antofagasta, Chile,
| | | | | |
Collapse
|
41
|
An SNP-based second-generation genetic map of Daphnia magna and its application to QTL analysis of phenotypic traits. BMC Genomics 2014; 15:1033. [PMID: 25431334 PMCID: PMC4301878 DOI: 10.1186/1471-2164-15-1033] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 11/12/2014] [Indexed: 02/08/2023] Open
Abstract
Background Although Daphnia is increasingly recognized as a model for ecological genomics and biomedical research, there is, as of yet, no high-resolution genetic map for the genus. Such a map would provide an important tool for mapping phenotypes and assembling the genome. Here we estimate the genome size of Daphnia magna and describe the construction of an SNP array based linkage map. We then test the suitability of the map for life history and behavioural trait mapping. The two parent genotypes used to produce the map derived from D. magna populations with and without fish predation, respectively and are therefore expected to show divergent behaviour and life-histories. Results Using flow cytometry we estimated the genome size of D. magna to be about 238 mb. We developed an SNP array tailored to type SNPs in a D. magna F2 panel and used it to construct a D. magna linkage map, which included 1,324 informative markers. The map produced ten linkage groups ranging from 108.9 to 203.6 cM, with an average distance between markers of 1.13 cM and a total map length of 1,483.6 cM (Kosambi corrected). The physical length per cM is estimated to be 160 kb. Mapping infertility genes, life history traits and behavioural traits on this map revealed several significant QTL peaks and showed a complex pattern of underlying genetics, with different traits showing strongly different genetic architectures. Conclusions The new linkage map of D. magna constructed here allowed us to characterize genetic differences among parent genotypes from populations with ecological differences. The QTL effect plots are partially consistent with our expectation of local adaptation under contrasting predation regimes. Furthermore, the new genetic map will be an important tool for the Daphnia research community and will contribute to the physical map of the D. magna genome project and the further mapping of phenotypic traits. The clones used to produce the linkage map are maintained in a stock collection and can be used for mapping QTLs of traits that show variance among the F2 clones. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-1033) contains supplementary material, which is available to authorized users.
Collapse
|
42
|
Routtu J, Ebert D. Genetic architecture of resistance in Daphnia hosts against two species of host-specific parasites. Heredity (Edinb) 2014; 114:241-8. [PMID: 25335558 DOI: 10.1038/hdy.2014.97] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2014] [Revised: 08/21/2014] [Accepted: 08/27/2014] [Indexed: 02/04/2023] Open
Abstract
Understanding the genetic architecture of host resistance is key for understanding the evolution of host-parasite interactions. Evolutionary models often assume simple genetics based on few loci and strong epistasis. It is unknown, however, whether these assumptions apply to natural populations. Using a quantitative trait loci (QTL) approach, we explore the genetic architecture of resistance in the crustacean Daphnia magna to two of its natural parasites: the horizontally transmitted bacterium Pasteuria ramosa and the horizontally and vertically transmitted microsporidium Hamiltosporidium tvaerminnensis. These two systems have become models for studies on the evolution of host-parasite interactions. In the QTL panel used here, Daphnia's resistance to P. ramosa is controlled by a single major QTL (which explains 50% of the observed variation). Resistance to H. tvaerminnensis horizontal infections shows a signature of a quantitative trait based in multiple loci with weak epistatic interactions (together explaining 38% variation). Resistance to H. tvaerminnensis vertical infections, however, shows only one QTL (explaining 13.5% variance) that colocalizes with one of the QTLs for horizontal infections. QTLs for resistance to Pasteuria and Hamiltosporidium do not colocalize. We conclude that the genetics of resistance in D. magna are drastically different for these two parasites. Furthermore, we infer that based on these and earlier results, the mechanisms of coevolution differ strongly for the two host-parasite systems. Only the Pasteuria-Daphnia system is expected to follow the negative frequency-dependent selection (Red Queen) model. How coevolution works in the Hamiltosporidium-Daphnia system remains unclear.
Collapse
Affiliation(s)
- J Routtu
- Zoologisches Institut, Universität Basel, Basel, Switzerland
| | - D Ebert
- Zoologisches Institut, Universität Basel, Basel, Switzerland
| |
Collapse
|
43
|
Yampolsky LY, Schaer TMM, Ebert D. Adaptive phenotypic plasticity and local adaptation for temperature tolerance in freshwater zooplankton. Proc Biol Sci 2013; 281:20132744. [PMID: 24352948 DOI: 10.1098/rspb.2013.2744] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Many organisms have geographical distributions extending from the tropics to near polar regions or can experience up to 30°C temperature variation within the lifespan of an individual. Two forms of evolutionary adaptation to such wide ranges in ambient temperatures are frequently discussed: local adaptation and phenotypic plasticity. The freshwater planktonic crustacean Daphnia magna, whose range extends from South Africa to near arctic sites, shows strong phenotypic and genotypic variation in response to temperature. In this study, we use D. magna clones from 22 populations (one clone per population) ranging from latitude 0° (Kenya) to 66° North (White Sea) to explore the contributions of phenotypic plasticity and local adaptation to high temperature tolerance. Temperature tolerance was studied as knockout time (time until immobilization, T(imm)) at 37°C in clones acclimatized to either 20°C or 28°C. Acclimatization to 28°C strongly increased T(imm), testifying to adaptive phenotypic plasticity. At the same time, Timm significantly correlated with average high temperature at the clones' sites of origin, suggesting local adaptation. As earlier studies have found that haemoglobin expression contributes to temperature tolerance, we also quantified haemoglobin concentration in experimental animals and found that both acclimatization temperature (AccT) and temperature at the site of origin are positively correlated with haemoglobin concentration. Furthermore, Daphnia from warmer climates upregulate haemoglobin much more strongly in response to AccT, suggesting local adaptation for plasticity in haemoglobin expression. Our results show that both local adaptation and phenotypic plasticity contribute to temperature tolerance, and elucidate a possible role of haemoglobin in mediating these effects that differs along a cold-warm gradient.
Collapse
Affiliation(s)
- Lev Y Yampolsky
- Department of Biological Sciences, East Tennessee State University, , Johnson City, TN 37614-1710, USA, Zoological Institute, Basel University, , Vesalgasse 1, Basel 4051, Switzerland
| | | | | |
Collapse
|