Browsing by study line "ei opintosuuntaa"
Now showing items 21-40 of 47
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(2022)Gravity has a modifying effect on plant architecture. The phytohormone auxin is known to transmit the signal of gravity perception from gravity-sensing cells to responsive tissues and cause an asymmetric growth response in the receiving organs. Intercellular auxin flux is mediated by many different transporter proteins, of which PIN-FORMED 3 (PIN3) is known to function as an auxin efflux carrier in gravitropic responses. The expression of PIN3 is known to locate in one cell layer of the shoot endodermis in herbaceous plant species and Populus hybrids. The objective of this study was to determine the location of PIN3 ortholog expression using silver birch (Betula pendula) as a model plant of a woody plant species. Agrobacterium tumefaciens C58 strain GV3101 (pMP90), harbouring binary vector pBpPIN3-erVEN-nosT2 containing erVenus (erVEN-YFP) as a marker gene under the BpPIN3 promoter and terminator nosT2, was used in the study to detect the gene expression. The expression vector was constructed by the Gateway® cloning method and transformed into in vitro shoot explants of silver birch by Agrobacterium-mediated transformation (AMT). In the study, transgenic lines were generated successfully, from which the fluorescence of erVEN was observed in the cross-section of the shoot with a fluorescence stereo microscope. The transgenicity of putative transgenic lines was confirmed by PCR of erVEN. BpPIN3 was likely to be expressed to endodermal tissue in the shoots of silver birch. This study can be considered as a screening step for the localization of BpPIN3 expression. The study facilitates the discovery of factors related to the regulation of PIN3 in tropic responses in woody plant species. This information can in the future be utilized in plant breeding to optimize plant architecture.
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(2021)During the last century, a decline in the canopy-forming foundation species Fucus vesiculosus has been observed in the Baltic Sea. The widely studied typical form of F. vesiculosus, that lives anchored to hard substrata, is at risk of further declines in the following century due to eutrophication and changes in water temperature and salinity. Fucus vesiculosus also exists in the Baltic Sea as a less common free-living form, which lives deposited in sheltered and shallow bays. This free-living form has been left understudied and little is known about their role in the ecosystem or the potential consequences of its disappearance. However, their occurrence may be equally or more under threat in the event of the aforementioned environmental changes. Additionally, it is currently unknown if mats of F. vesiculosus cause anoxia in the sediment below. This thesis will investigate the macroepifaunal and macroinfaunal communities associated to the presence of free-living F. vesiculosus across different sites in both Finland and Sweden. We will also estimate if F. vesiculosus causes anoxia. For this study, replicate frames of F. vesiculosus, including all vegetation and epifaunal community, were collected using mesh bags. Infaunal samples were randomly collected using benthic cores, both under the mat of F. vesiculosus and the adjacent bare soft bottom. All macroinvertebrates were identified to the lowest possible taxa, counted and weighed. Morphological measurements of F. vesiculosus thalli, such as length of thallus and wet weight, were recorded for every frame. Our results showed that the presence of free-living F. vesiculosus has a consistent effect across the two study locations. We found that increasing wet weight of F. vesiculosus significantly increased the abundance and biomass of the macroepifauna. The highest infaunal animal abundance and biomass were found in the bare sediment with high occurrence of opportunistic taxa. However, we found potential evidence to suggest that the presence of F. vesiculosus mats does not cause anoxia in the sediment. This study provides a much-needed first look into the macrofaunal communities associated to the free-living Fucus vesiculosus. Our study demonstrated that free-living F. vesiculosus is a potential foundation species in shallow, sheltered bays of the Baltic Sea by increasing the number of present taxa compared to adjacent bare sediment. Higher F. vesiculosus biomass directly increased the abundance and biomass of the macroepifaunal community, and the presence of free-living Fucus vesiculosus was not found to have significant negative effects on the associated macroinfaunal community.
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(2022)Environmental factors are important tools in constructing methane flux models and estimations. Among the abiotic factors, plants and their functional groups have been noted to have significant effect on methane fluxes for three reasons. First, the vegetation community compositions express their abiotic environmental factors that affect not only the plants, but also local methanogen and methanotroph communities. Second, the vegetation itself might produce methane emissions and have a direct effect on methane balance. Third, the plant functional groups and species have differences in their chemical and physical properties that support different methanogen communities and therefore have an indirect impact on methane fluxes. In this study, methane fluxes of different plant communities were observed during one growing season in northern boreal catchment area in Muonio. Study focuses to determine the link between methane fluxes and abiotic and biotic environmental factors in different vegetation types. Closed chamber technique was used to measure methane and carbon dioxide fluxes from 23 plots every two weeks in period of June-August. Environmental data, such as moisture, temperature species composition etc. were collected from the plots. Vegetation types for each plot were determined via ordination analysis. Linear mixed-effects regression model and generalized additive model were applied and compared to observe the relationships of methane and environmental factors in different vegetation types. Dataset was divided into four vegetation types in clustering analysis: wet fen, pine bog, spruce swamp and forest. The greatest amount (average 5959 µg/m²/h) and biggest range (standard deviation 5285 µg/m²/h) of methane emissions were observed on wettest fen-like study sites. Peatland types in general acted as net methane sources. The driest, forest-like vegetation type acted as a net methane sink. The amount (average -107 µg/m²/h) and range (standard deviation 117 µg/m²/h) of methane fluxes were very moderate in comparison to peatland types. These effects intensified towards the climax of growing season. The most significant environmental factors were mostly abiotic on driest study sites and the whole plant biomass was more significant biotic methane flux regulating factor than plant functional groups. On wetter study sites, the role of abiotic factors decreased, and plant functional group increased. Graminoids were linked to bigger methane emissions especially on wetter study sites. Forest mosses and different shrub types seemed to have a link with lower methane emissions or methane absorption. The effect of other plant functional groups on methane fluxes varied more, and their role remains unclear. None of the environmental factors could estimate the methane flux alone, and the methane budget seems to be a sum of multiple variables in each vegetation type. The role of plant functional groups varied in different vegetation types and was dependent on surrounding vegetation. More research is needed to get better tools to estimate methane balance and to understand the underlying mechanisms in climate and environmental change.
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(2024)Nuclei isolation is a method used e.g. as a part of chromatin structure research. DNA structure can be examined in its 3D form from isolated nuclei because DNA is still wrapped around the histone proteins. Examining the chromatin structure can offer information e.g. about gene expression and how it is regulated. Isolating nuclei from plant cells demand more optimization compared to animal cells because of the cell wall, chloroplasts and secondary metabolites. The presence of organellar DNA can hamper the later DNA analysis. Secondary metabolites can hinder the actual isolation process. Finding the suitable isolation protocol for species of interest may need careful optimization of different aspects. Different species can differ from each other based on the structural and biochemical characteristics and because of this the same protocol may not ensure as good results for them. Different tissue types of the same species may have also differences in their biochemical and structural characteristics. In this thesis work, three different isolation protocols were used for three plant species; Pinus sylvestris, Betula pendula and Arabidopsis thaliana. The purpose of the work was to compare the results from each nuclei isolation protocol. Optimization of isolation protocol for P. sylvestris and B. pendula would help the isolation process for later research. Thesis work was done to get guidance for this optimization. Samples handled with different protocols were different from each other based on the sample concentration (particles/mL) and the average size of isolated particles. Chloroplast contamination was tested with chloroplast specific primers with PCR. None of the samples were free from chloroplasts.
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(2021)The three-spined stickleback (Gasterosteus aculeatus) is a model organism for studies of parallel evolution in the wild; marine stickleback populations have repeatedly colonized and successfully adapted to different brackish and freshwater habitats. During Pleistocene glaciations, three-spined stickleback populations inhabiting high-latitude areas of Europe were eradicated, whereas populations residing in (or moving to) the south persisted in refugia. After the retreat of the ice sheets covering northern Europe, the high-latitude areas became recolonized by migration from south, and hence, today’s northern European populations are relatively young. Population genetic studies of European three-spined sticklebacks have usually been conducted at high-latitude areas where freshwater populations are typically less than 10.000 years old. Few studies have focused on southern populations, where more of the ancestral diversity is likely to reside. These studies have utilized a limited number of microsatellite markers and mtDNA sequence fragments, whereas studies of southern populations focusing on genome-wide diversity, in particular from the edge of the southern distribution limit in the Iberian Peninsula, are still missing. Here, I wanted to cover this gap in knowledge by carrying out an empirical and statistical study with RAD-seq data from southern and northern European populations of three-spined stickleback. The main aims of this study were two-fold. First, to investigate whether the southern European freshwater populations of the three-spined stickleback – which currently lack or have limited connection to ancestral marine populations carrying most of the standing genetic variation (SGV) – have lost genetic diversity due to population bottlenecks and inbreeding as compared to their northern European counterparts. Second, to compare the degree of genetic parallelism in southern vs. northern European populations in genomic regions which have been shown to be consistently associated with freshwater colonization in earlier studies. Under the assumption that the lack of continued access to SGV in the ancestral marine population reduces the likelihood of parallel evolution, I hypothesized that the degree of genetic parallelism in genomic regions subject to positive selection in freshwater environments is lower in the southern than in northern European populations. However, if a reduction in genetic diversity and/or cessation of gene flow between southern European freshwater and marine populations occurred following freshwater adaptation, the opposite pattern could be expected. I paid particular attention to chromosomal inversions associated with marine-freshwater adaptations identified in previous studies. The results confirmed my expectation of reduced genetic diversity in southern as compared to northern European stickleback populations. On the other hand, and contrary to what I expected, analysis of clusters of global parallelism involved in freshwater adaptation revealed that southern European populations exhibit a higher degree of genetic parallelism in response to freshwater colonisation than those from northern Europe. This suggests that the loss of genetic diversity in southern populations has occurred after they had adapted to freshwater environments, explaining the high degree of genetic parallelism in spite of the current low levels of genetic diversity. In addition, it could be that selection pressures in south are more homogenous than in north, which would also explain the higher degree of genetic parallelism observed in southern Europe. The findings presented here, challenge the current paradigm that parallel evolution is unlikely in populations with low genetic diversity and that have experienced recent bottlenecks.
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(2020)Biogeography is a crucial aspect to ecological studies, as an ecosystem is comprised of the physical habitat, the organisms living there, and the interactions of these components. Community structure, and therefore functioning, are inherently of a spatial nature. Spatial structure of populations is often crucial basic knowledge for understanding the evolutionary history, dispersal patterns, and resilience of any given species. One aspect of spatial structure, and the topic covered in this study, is community distance decay, or the rate at which community similarity decreases with physical distance. More of the landscape is constantly being altered by humans on a large scale, so it is increasingly important to understand the effects that these anthroprogenic changes to the environment has on local populations. Studying community distance decay helps form understanding of dispersal and establishment limitations for different organisms, which is necessary for mitigating biodiversity loss. Many studies show that habitat fragmentation and loss has greatly impacted the structure of plant and animal communities, but there has been much less focus on fungal communities. There’s no certainty that fungi is impacted in the same ways, given the different lifestyles and dispersal methods, so the aim of this study is to contribute to the much needed research on fungal community structure at various scales. This aim is addressed by examining fungal community distance decay from small scale of a couple kilometers or less to a fairly large scale encompassing a landscape of primarily urban, forest, and agricultural areas. The five main localities of sampling were in middle and southern Finland: Helsinki, Lahti, Tampere, Jyväskylä, and Joensuu. Sampling locations and plot design were chosen to allow the comparison of communities separated by a mosaic, as well as along a short rural to urban gradient, to assess the effects of habitat type. From each location, six plots were decided, two in urban core, one in urban edge, two in natural core, and one in natural edge. The role of dispersal ability and functional traits in distance decay is also studied by comparing results from two different methods of fungi sampling, which were collecting spores from the air using cyclone samplers, and taking soil cores to gather fungal biomass. All samples were DNA analysed with high-throughput sequencing and the results from the DNA barcoding were used to create OTU clusters, by which the 30 plots could be compared through relative abundances of OTU’s. I determined the similarity of fungal communities using an analysis of similarity (ANOSIM) test in R, where all possible variables (site, habitat type, sample type) were used as a grouping in individual tests, thereby indicating which variable is associated with highest community difference. I also determined the differences in functional groups and major taxonomic levels among locations and sampling method using interactive taxanomic (KRONA) charts. Results showed that there are differences in fungal community structure among habitat type and sampling type. However there was greater difference at the level of plots than site locations, so clear patterns of strong community distance decay with physical distance was not measured in this study. The results suggest that fungal communities can be fairly impacted by human caused habitat change, and individual characteristics, such as dispersal methods or lifestyle, effect the rate of community distance-decay. This provides a valuable early insight into fungal community patterns, which need deeper study to understand the complexities and mechanisms behind them.
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(2024)The many symbiotic microbes associated with plants can represent the first line of defence against viral pathogens, which can have profound impacts on plant health and productivity. Unfortunately, although countless studies have investigated variations in the composition of microbial communities associated with crops, showing benefits in the plants’ nutrient acquisition, stress tolerance or growth promotion, much less is known about how viruses might affect the composition of the microbiota associated with plants, and especially non-crop plants. Furthermore, we also often lack an understanding of how plant viruses are transmitted across their environment. Addressing these knowledge gaps is bringing us closer to better describe and manage the complex relationships between plant microbiota and viral pathogens in their natural environment. The main objective of my Master’s study is to examine variations in the bacterial community associated with a plant in the agricultural landscape, and to identify potential players in microbial community changes. With this in mind, I chose to work with the ribwort plantain, Plantago lanceolata, because it has a widespread distribution, it is present around cultivars, and there is extensive knowledge of its biology and genetics. Thus, P. lanceolata, represents an excellent system for investigating the causes of variation in the plant-associated microbiota. More precisely, I worked with the P. lanceolata population evolving in the Åland Islands, in Southwestern Finland, which has been the target of long-term ecological and evolutionary metapopulation studies. The population is also known for co-evolving with several viral pathogens, and with diverse Hemiptera insects (plant sucking-insects) that have been suggested as possible vectors of the viruses between plants. I collected P. lanceolata leaves, and insects found on P. lanceolata specimens from 28 habitat patches, or meadows, from five localities across the Åland Islands (Geta, Sund, Lemland, Finström, Eckerö). I extracted DNA from a total of 10 leaves per patch, as well as 60 Hemiptera specimens (of several uncharacterized species). I screened for viral infection in all samples by amplifying the viral loci for reverse transcriptase form Plantago latent caulimovirus (cauV) and the replication associated protein gene from Plantago lanceolata latent virus (PlLV). In parallel, I characterized the bacterial communities associated with each plant and insect through metabarcoding of the highly variable V5-V6 region of the 16S rRNA bacterial gene. My MSc's project shows that bacterial species richness (alpha-diversity metric) and community composition (beta-diversity metric) vary between plant and insects. But that they do not vary between the virus-infected and uninfected plants tested, and neither between geographical locations within the Åland Islands. This is the first study investigating the effects of two virus infections on the microbiota of a common weed from the Åland Islands. It provides preliminary data for the study of how the bacterial microbiota of P. lanceolata might respond to virus infections, and how viruses might be transmitted between individual plants.
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(2021)Ilmastonmuutos koettelee ankarimmin planeettamme pohjoisia alueita. Näiden alueiden eliöyhteisöt ovat ennestään erityisen herkkiä ympäristön muutoksille. Vaikka arktisen ympäristön fysikaaliset muutokset ovat jo monin paikoin nähtävillä, ovat tiedot näiden muutosten vaikutuksista alueen eliöyhteisöihin ja ekologisiin vuorovaikutussuhteisiin edelleen hyvin puutteelliset. Pohjoisten keväiden aikaistuminen altistaa yhteisöt fenologiselle irtautumiselle, jossa läheisessä ekologisessa vuorovaikutuksessa olevat lajit ajautuvat esiintymisaikojensa suhteen erilleen. Pölyttäjähyönteisen sekä pölytettävän kukkakasvin tapauksessa tästä voi olla seurauksena pölytystehon väheneminen. Tämän ja ilmastomuutoksen muiden seurausten ennustamiseksi käytetään usein nk. ajan ja tilan rinnastus –menetelmää. Menetelmän oletuksena on, että eliöt reagoivat ympäristötekijöihin samalla tavalla, tapahtuivatpa ne sitten ajallisesti tai paikallisesti. Selvittääkseni, onko arktisella alueella havaittavissa fenologista irtautumista, tarkastelen lapinvuokon sekä lajin pölyttäjäyhteisöön kuuluvan 14 hyönteisheimon fenologiaa Koillis-Grönlannissa. Tarkastellakseni, miten ilmaston vaihtelu vuosien välillä kuvastuu hyönteisaktiviteetin ajoittumiseen ja lajiryhmien väliseen vaihteluun, hyödynnän kahdenkymmenen vuoden aikasarjaa (jatkossa: aikasarja-aineisto). Selvittääkseni, miten ilmaston vaihtelu tilassa heijastuu paikallisiin eroihin pölyttäjäaktiviteetin fenologiaan, seuraan hyönteisaktiviteetin ajoittumisen yhden kasvukauden aikana maaston eri osissa (jatkossa: tila-aineisto). Molemmista aineistoista selvitän, mikä ympäristötekijä määrittää voimakkaimmin pölyttäjäyhteisön fenologiaa, keskittyen lumenlähtöpäivään ja lämpösummaan. Lopuksi arvioin, kuinka hyvin ajallinen ja paikallinen ulottuvuus vastaavat toisiaan. Näin pyrin selvittämään sitä, kuinka käyttökelpoinen ajan ja tilan rinnastus –menetelmä on pohjoisten pölyttäjäyhteisöjen tutkimuksessa. Totesin lumenlähtöpäivän selittävän lapinvuokon pölyttäjäyhteisön fenologiaa kokonaisuutena parhaiten. Tämä pätee sekä tila- että aikasarja-aineistossa. Lumenlähtöpäivän ja lämpösumman vaihdellessa eri lajiryhmien ajoitus muuttuu eri tavoin. Muutokset tilassa ja ajassa olivat lapinvuokon tärkeimpien pölyttäjäryhmien kohdalla suhteellisen yhteneväiset, mutta eräiden muiden ryhmien (esim. kukkakärpästen) kohdalla ja samalla koko yhteisön tasolla ennusteet olivat heikompia. Tulokseni osoittavat, että ilmaston vaihdellessa arktisissa yhteisöissä on nähtävissä fenologista irtautumista. Yhteisön sisällä eri lajiryhmät reagoivat sekä lumenlähtöpäivään että lämpösummaan eri tavoin. Tämä altistaa yhteisöjä fenologiselle irtautumiselle ympäristön edelleen muuttuessa. Pölyttäjäfenologiaa tutkittaessa ajan ja tilan rinnastus -menetelmä näyttää toimivan hyvin lapinvuokon ja tämän kasvilajin tärkeimpien pölyttäjäheimojen kohdalla. Koko yhteisön tasolla rinnastuksen ennusteet ovat kuitenkin puutteelliset, sillä joidenkin ryhmien ennusteet eroavat toisistaan merkittävästi sekä ajassa että tilassa. Tulevaisuudessa tulisikin selvittää tarkemmin sitä, kuinka nyt havaittu pölyttäjäyhteisön fenologinen epäyhtenäisyys heijastuu lajien välisiin vuorovaikutussuhteisiin eri trofiatasojen välillä.
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(2021)Ornamentit ovat hyödyllisiä kumppaniehdokkaiden arvioimisessa ja kilpailussa toisia lisääntymishalukkaita yksilöitä vastaan. Naaraiden ornamenttien kehittymistä edistää koiraan korkeat lisääntymiskustannukset, kuten poikasten hoito ja pesän rakentaminen. Kehitystä rajoittavat naaraan ornamenteista koituvat kustannukset, jotka rajoittavat jälkeläisten määrää ja selviytymistä munasoluihin käytettävissä olevien resurssien kautta. Ihmisten toiminnasta johtuva lisääntyvä rehevöityminen vähentää näkyvyyttä ja siten haittaa ornamenttien käyttöä niin kumppaneiden houkuttelussa ja arvioinnissa kuin samaa sukupuolta olevien kilpailussa. Lisääntymiskauden aikana sekä kolmipiikkikoirailla että naarailla on havaittavissa ornamentteja. Itämeren rehevöitymisen on havaittu vaikuttavan kolmipiikkien lisääntymiseen usealla tavalla, kuten seksuaalivalinnan heikkenemisellä ja muutoksilla munien kuoriutumistodennäköisyyteen. Kolmipiikkinaaraiden ornamentin käyttötarkoitukset ja rehevöitymisen vaikutukset siihen ovat kuitenkin vielä tuntemattomia. Tutkin rehevöitymisen vaikutusta kolmipiikkinaaraan ornamenttiin avoimessa ja suojaisassa habitaatissa sekä ornamentin yhteyttä naaraan hedelmällisyyteen. Selvitin, vaikuttaako ornamentin voimakkuus naaraan kumppaninetsintäaktiivisuuteen, koska ornamentin on aiemmin havaittu kertovan lisääntymismotivaatiosta. Lisäksi testasin, suosivatko koiraat ornamentillisia naaraita ja vaikuttaako näkyvyys koiraan valintaan. Tulosteni mukaan naaraan ornamentti ei ilmaissut naaraan hedelmällisyyttä eikä habitaatin suojaisuus vaikuttanut ornamentin kehitykseen. Ornamentin ylläpito ja kumppaninetsintä ovat molemmat resursseja kuluttavia toimintoja. Saadakseen kumppanin heikompilaatuisen naaraan on mahdollisesti panostettava enemmän koiraan etsimiseen kuin ornamenttiin ja siksi havaitsin heikompiraitaisten naaraiden olevan aktiivisempia kumppaninetsinnässä. Naaraiden ornamentti voimistui naaraan ollessa kosiskelevan koiraan seurassa. Kolmipiikkikoiraat suosivatkin ornamentillisia naaraita ja kykenivät valitsemaan ornamentillisen naaraan näkyvyyden heikkenemisestä huolimatta. Toisaalta näkyvyyden heikkeneminen vähensi koiraan kosiskeluaktiivisuutta. Kolmipiikeillä molemmat sukupuolet käyttävät ornamentteja kumppaninvalinnassa, mutta naaraan ornamentin hyödyt koiraalle vaativat vielä lisää tutkimusta.
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(2023)Land-use change stands behind the current biodiversity crisis and all it entails in terms of ecosystem services. Guinea-Bissau, in West Africa, is originally characterized by a forest- savanna mosaic biome. However, while savannas have long been planted with rice, both rice paddies and forest remnants are now being converted into cashew monocultures – the only cash crop in the country – at unprecedented rates. The ecological impact of such rapid change is largely unknown. To help fill this gap, we examined how three diversity metrics – rarefied species richness, abundance and composition – varied across forest remnants, cashew orchards and rice paddies for amphibians and reptiles in northern Guinea-Bissau. To do so, visual encounter surveys were carried across 21 sampling sites, seven of each habitat type. A total of 703 amphibian and 266 reptile encounters was recorded from nine and 14 taxa, respectively. The results show class-specific responses to habitat type. Amphibians’ diversity in forest remnants and cashew orchards was similar across all metrics, but rice paddies had a higher abundance and unique composition compared to forest remnants. Reptiles’ abundance was highest in cashew orchards and this habitat had a distinct composition, when compared to forest remnants. Rice paddies sustained both lower reptile richness and abundance. Overall, our results are not in agreement with the expected detrimental impacts of cashew expansion, which might be due to the still high heterogeneity of habitat types within the landscape. Rice paddies proved particularly important for amphibians, and for open-habitat reptiles, boosting overall species diversity. In face of the eminent habitat conversion, maintaining heterogeneous landscapes, including the persistence of both forest remnants and rice paddies, will allow minimizing biodiversity loss in West Africa.
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(2017)Yersinia pseudotuberculosis voi aiheuttaa ihmiselle suolistoinfektion, yersinioosin. Se tarttuu kontaminoituneiden elintarvikkeiden välityksellä, ja Suomessa on todettu useita epidemioita viimeisen 20 vuoden aikana. Yersinia-suku kuuluu Enterobacteriaceae-heimoon, ja siihen kuuluu tällä hetkellä 18 lajia. Y. pseudotuberculosis-lajin lisäksi sukuun kuuluu kaksi ihmispatogeenia, Yersinia enterocolitica ja Yersinia pestis. Y. enterocolitica on myös elintarvikevälitteinen patogeeni, Y. pestis puolestaan tunnetaan ruton aiheuttajana. Y. pseudotuberculosis kasvaa hyvin jääkaappilämpötiloissa, jolloin nykyaikaiseen elintarvikehygieniaan oleellisena osana kuuluva kylmäsäilytys ei estä sen lisääntymistä elintarvikkeissa. Sen vuoksi onkin tärkeä tutkia tekijöitä, joilla on merkitystä Y. pseudotuberculosis-bakteerin kylmänsiedossa ja muissa stressiolosuhteissa. RNA-helikaasit ovat proteiineja, jotka avaavat kaksijuosteista RNA:ta. Niihin kuuluu useita proteiiniperheitä, mutta suurin niistä on DEAD-box-helikaasiperhe. DEAD-box-helikaaseja löytyy kaikista eliöryhmistä, ja ne osallistuvat kaikkiin RNA-metabolian vaiheisiin. Ne ovat ATP-riippuvaisia helikaaseja ja ne kykenevät avaamaan vain lyhyitä kaksijuosteisia alueita. Y. pseudotuberculosis IP32953- genomi sisältää viisi DEAD-box-helikaasia koodaavaa geeniä, csdA, dbpA, rhlB, rhlE ja srmB. RhlB osallistuu mRNA-molekyylien hajottamiseen osana RNA-degradosomia. Muut proteiinit osallistuvat pääasiassa ribosomin rakentumiseen. Escherichia coli -bakteerilla aiemmin tehdyn tutkimuksen perusteella tiedetään, että CsdA:n ja SrmB:n puuttuminen soluista saa aikaan kylmäherkän fenotyypin. CsdA:n roolia on tutkittu myös Y. pseudotuberculosis-lajilla, jossa toimimaton CsdA heikentää kasvua kylmässä. Tämän tutkielman tarkoituksena oli tutkia RNA-helikaasien vaikutusta Y. pseudotuberculosis IP32953-kannan kasvuun erilaisissa stressiolosuhteissa. RhlE-, DbpA- ja SrmB-deleetiomutanttikantoja kasvatettiin optimilämpötilan (28 °C) lisäksi kylmässä (3 °C), korkeassa suolapitoisuudessa sekä alhaisessa ja korkeassa pH:ssa. Kasvun aikana mitattiin bakteerien kasvua OD600nm-mittausten avulla, ja aineiston perusteella kannoille piirrettiin kasvukäyrät kaikissa olosuhteissa. Lisäksi aineistosta laskettiin käyrän alle jäävä pinta-ala, jonka perusteella tutkittiin kasvuerojen tilastollista merkitsevyyttä Studentin t-testillä. Kannoille määritettiin myös kasvunopeudet eri olosuhteissa. Deleetiomutanttien kasvussa huomattiin eroa alhaisessa lämpötilassa, jossa kaikki deleetiomutanttikannat tilastollisesti merkitsevästi kasvoivat villityypin kantaa huonommin. Lisäksi ΔsrmB -kanta kasvoi tilastollisesti merkitsevästi heikommin optimilämpötilassa ja korkeassa pH:ssa. Näyttääkin siis siltä, että DEAD-box-helikaasit ovat Y. pseudotuberculosis-bakteerilla suuremmassa roolissa kuin E. coli-bakteerilla, ja niitä tarvitaan erityisesti alhaisissa lämpötiloissa.
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(2020)Viime vuosikymmenien maaseutuympäristöjen muutokset, kuten lisääntynyt maankäytön tehostuminen ja kasvinsuojeluaineiden käyttö, ovat saaneet monet Euroopan maaseutuympäristöjen lintujen kannat taantumaan. Jotta lintukantojen muutoksia voitaisiin ymmärtää ja suojelutoimia suunnitella, on lintujen elämänkierron eri vaiheiden, kuten pesimämenestyksen ja elossasäilyvyyden, sekä selviytymiseen vaikuttavien tekijöiden tutkiminen tärkeää. Myös Suomessa maaseutuympäristöjen linnuston tutkimukselle on tarvetta: uusimmassa Suomen luonnon uhanalaisuusarvioinnissa (2019) uhanalaisia tai silmälläpidettäviä maatalousympäristöjen lintulajeja oli 18, mikä on neljä enemmän kuin neljä vuotta aiemmassa arvioinnissa. Yksi näistä on Suomen voimakkaimmin taantunut maalintulaji, peltosirkku (Emberiza hortulana), jonka kanta on kutistunut 80-luvulta alle yhteen prosenttiin. Tämän tutkielman tavoitteena on selvittää yksilöllisin tunnistein merkittyjen lintujen avulla, onko Suomen aikuisten peltosirkkukoiraiden elossasäilyvyys ollut vuosina 2013–2019 poikkeavan matala, mikä voisi selittää lajin kantojen voimakasta laskua. Tavoitteena on myös tarkastella elossasäilyvyyden vuosittaista ja alueellista vaihtelua, peltosirkkujen kannankehityslukuja, sekä selvittää vaikuttivatko muuttokäyttäytymisen tutkimista varten kiinnitetyt valopaikantimet (loggerit) elossasäilyvyyteen. Tutkielman aineisto on kerätty vuosina 2013–2019 niiltä alueilta, joilla peltosirkun on havaittu pesivän. Aineisto koostuu 210 aikuisen (+1kv; vanhempi kuin ensimmäistä kalenterivuottaan elävä lintu) peltosirkun pyynti-jälleenpyynti-aineistosta, jota käyttäen tehtiin elossasäilyvyysanalyysit, sekä peltosirkkujen reviirikartoituksesta, jota käytettiin kannankehityslukujen laskemiseen. Elossasäilyvyysanalyysit tehtiin käyttäen CJS -mallia (Cormack-Jolly-Seber) MARK -ohjelmassa. Analyysia varten aineistosta poistettiin naaraat, paikkaansa vaihtaneet peltosirkut ja Itä-Suomen vaillinaisesti seuratut yksilöt, sekä muodostettiin kaksi pääanalyysia: koko Suomen analyysi ja alueellinen analyysi. Koko Suomen analyysissa tarkasteltiin, oliko loggerilla vaikutusta linnun elossasäilyvyyteen ja vaihteliko elossasäilyvyys vuosien välillä. Alueellisessa analyysissa Suomen peltosirkut jaettiin kolmeen alueeseen: pohjoiseen, lounaiseen ja eteläiseen. Analyysissa tarkasteltiin, onko elossasäilyvyydessä eroa alueiden välillä ja vaihteleeko elossasäilyvyys vuosien välillä. Lopuksi laskettiin R-ohjelmiston Rtrim -paketilla kannankehitysluvut koko Suomelle sekä alueellisessa analyysissa käytetyille kolmelle alueelle. Analyysin tulos oli että Suomen peltosirkkukoiraiden elossasäilyvyys vuosina 2013–2019 oli 43,3 % koko tutkimusjaksolle. Loggeri vaikutti negatiivisesti elossasäilyvyyteen, mutta alueiden tai vuosien välillä ei ollut merkitsevää vaihtelua. Kannankehitysluvut olivat laskusuuntaisia ja niissä oli alueiden välillä merkitseviä eroja. Koko Suomessa kanta laski 19,4 % vuodessa. Alueista suurin lasku oli lounaassa, jossa kanta laski 26,5 % vuodessa. Suomen peltosirkkukoiraiden elossasäilyvyysanalyysin tulosta verrattiin muiden samankokoisten (10–40g) pitkän matkan muuttavien varpuslintujen julkaistuihin elossasäilyvyyslukuihin (41,9-58,0 %; 15 eri lajia). Vertailun perusteella Suomen peltosirkkukoiraiden elossasäilyvyys ei ole ollut poikkeavan matala, eikä siten vaikuta olevan ainakaan tärkein voimakasta kannanlaskua selittävä tekijä. Tämän tutkielman tulosten mukaan Suomen peltosirkkujen kannanlaskun taustalla on luultavimmin muita tekijöitä kuin aikuisten koiraiden elossasäilyvyys, kuten aikuisten naaraiden tai nuorten lintujen (ensimmäistä kalenterivuottaan elävät linnut) kestämättömän suuri kuolleisuus tai kestävälle populaatiokehitykselle liian heikko pesimätulos. Elossasäilyvyydessä ei havaittu myöskään alueellisia vaihteluita, mutta kannankehitysluvuissa näin oli, minkä perusteella ainakin jotkin populaatiokokoa säätelevät tekijät ilmenevät joillakin pesimäalueilla voimakkaammin kuin toisilla. Näin ollen eritoten pesintämenestykseen vaikuttavia tekijöitä kannattaisi kiireellisesti tutkia, jotta peltosirkun kannankehityksen suunta saataisiin tietoon perustuvan suojelusuunnitelman avulla käännettyä.
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(2021)Natural scientists study a wide variety of species, but whether they have identified all studied samples correctly to species is rarely evaluated. Species misidentification in empirical research can cause significant losses of money, information, and time, and contribute to false results. Thus, I study the abundance of species misidentification and ecologists’ perceptions of such mistakes through a web survey targeting researchers from scientific institutes around the globe (including universities, research societies and museums) who completed their doctoral degree in any ecology-related field of science. I received 117 responses with either work or educational background from 30 countries. I found that species misidentification widely existed in respondents’ research: almost 70% of the respondents noticed species misidentification in their own research, while the estimated proportion of existing studies with species misidentification was 34% (95% CI: 28% - 40%). Although misidentification was mainly found during specimen collection, specimen handling and data analysis, misidentifications in reporting stages (writing, revision and after publishing) could persist until publication. Moreover, according to respondents, reviewers seldom comment about species identification methods or their accuracy, which may affect respondents’ (both leading and not leading a research team) low reporting frequency about the possibility of misidentification. Expert checking, training students, and DNA barcoding are the most prevalent approaches to ensure identification accuracy among respondents. My results imply that species misidentification might be widespread in existing ecological research. Although the problem of species misidentification is widely recognized, such an issue seldom be appropriately handled by respondents. To increase the accuracy of species identification and maintain academic integrity, I suggest that researchers need to focus more on the study species (e.g., sampling process, identification method, and accuracy) when writing and reviewing papers. Furthermore, I appeal for guidelines about reporting species identification methods and their accuracy in papers, as well as research on education about identification skills in universities, as these two topics may constrain the precision of species identification.
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(2021)Pohjoisilla soilla on suuri merkitys globaaleissa biogeokemiallisissa kierroissa niiden kerrostaman ja vapauttaman hiilen vaikutuksesta. Ilmastollisten tekijöiden on todettu olevan yhteydessä suon hydrologisiin vaihteluihin, kuten kuivumiseen, vettymiseen, routaantumiseen tai roudan sulamiseen. Muutokset suon hydrologiassa ovat menneisyydessä heijastuneet vuorovaikutteisesti soiden kasvillisuuteen ja niiden rooliin maailmanlaajuisesti merkittävinä hiilinieluina. Pohjoisten ikiroutasoiden ainutlaatuinen ja rikas habitaatti on vaarantunut nykyisen ilmaston lämpenemisen myötä. Maisterintutkielmani tavoitteena on arvioida mahdollisia ilmaston lämpenemisen aiheuttamia vaikutuksia pohjoisiin soihin tutkimalla viimeisten vuosisatojen aikana tapahtuneita muutoksia suokasvillisuudessa. Tutkielmassa selvitin, miten tutkimussuoni kasvillisuus on muuttunut ja millaisia yhteyksiä voidaan havaita eri ilmastovaiheiden merkittävimpiin lämpötilan muutoksiin. Keskityin analysoimaan näitä muutoksia kasvimakrofossiili-analyysin avulla. Näytesarjat ajoitettiin radiometrisin menetelmin. Tulokset osoittivat tutkimussuon käyneen läpi kuivan kasvillisuuden vaiheita sekä ilmastohistorian lämpiminä että kylminä ajanjaksoina. Nykypäivän lämpenemisen aikana eri näytepisteissä on tapahtunut sekä kuivumista että siirtymiä kosteaan suoekosysteemiin ikiroudan sulamisen jälkeisinä ajanjaksoina. Tutkimukseni tulokset auttavat osaltaan ymmärtämään ympäristössä ja ilmastossa tapahtuvien muutosten kompleksista vaikutusta pohjoisiin suoekosysteemeihin. Tutkimuksen perusteella voidaan arvioida nykyisen ilmastonmuutoksen mahdollisia vaikutuksia tutkimussuohon, sekä rinnan muiden tutkimusten kanssa yhteyksiä pohjoisten soiden tulevaisuuden hiilitasapainoon ja suuren mittakaavan biogeokemiallisiin kiertoihin.
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(2018)Lepakot ovat suuri, monimuotoinen ja ekologisesti merkittävä nisäkäslahko. Viime vuosikymmenien aikana ne ovat paljastuneet myös merkittävien zoonottisten taudinaiheuttajien kantajiksi. Suomessa esiintyy kolmetoista lepakkolajia, joista suurin osa esiintyy täällä levinneisyysalueensa pohjoislaidalla ja joiden kantamista taudinaiheuttajista on tehty vielä hyvin vähän tutkimuksia. Tutkielmassani selvitän korona- ja paramyksovirusten esiintymistä eteläisen Suomen lepakoilla vuosina 2013-2016. Lisäksi pyrin kerätyn aineiston perusteella selvittämään, onko näytteitä luovuttaneiden lepakoiden iällä, näytteiden keruukuukaudella tai näytteiden keruualueella vaikutusta löydettyjen virusten esiintyvyyteen. Aineistona käytettiin muiden tutkimusprojektien yhteydessä lepakoilta kerättyjä uloste- ja anaalipyyhkäisynäytteitä sekä lepakoiden päivehtimispaikoilta kerättyjä ulostenäytteitä. Näytteistä eristettiin RNA ja ne seulottiin koronaviruksia ja paramyksoviruksia tunnistavilla ja optimoiduilla kvantitatiivisilla käänteistranskriptio- PCR-menetelmillä (RT-qPCR) ja löydökset varmistettiin tavallisilla käänteistranskriptio-PCR-menetelmillä (RT-PCR). Jälkimmäisistä reaktioista saadut tuotteet myös sekvensoitiin. Ulostenäytteiden seulonnan tuloksista kertyneestä aineistosta tehtiin tilastolliset analyysit yleistetyillä lineaarisilla sekamalleilla, joissa vastemuuttujana käytettiin viruksen esiintymistä ja mallin muuttujina näytteen luovuttaneen lepakon ikäryhmää ja lajia, näytteen keräyskuukautta ja eliömaakuntaa, josta näyte oli kerätty. Mallien satunnaistekijöinä käytettiin näytteiden keräyskuntaa tai näytteiden keräysvuotta. Sekvenssiaineistosta tehtiin fylogeneettiset analyysit käyttäen suurimman todennäköisyyden (Maximum Likelihood) menetelmää ja Bayesilaista menetelmää, joiden tuloksina saatiin kaksi fylogeneettista puuta. Neljän vuoden aineistosta todettiin yhteensä 18 lepakkoyksilöä, jotka kantoivat koronaviruksia, mutta paramyksoviruksia ei aineistosta löydetty. Tilastolliseen tarkasteluun hyväksyttiin 77 ulostenäytettä, joista 13 oli positiivisia koronaviruksille. Anaalipyyhkäisynäytteistä kerättiin 38 kappaletta ja näistä 5 oli positiivisia koronaviruksille. Päivehtimispaikoilta kerättyjä ulostenäytteitä tutkittiin 28 kappaleitta ja näistä 4 oli koronaviruspositiivisia. Koronaviruksia löydettiin Varsinais-Suomen, Uudenmaan, Etelä-Pohjanmaan ja Pohjois-Savon eliömaantieteellisiltä alueilta. Uloste- ja anaalipyyhkäisynäytteiden perusteella koronaviruksia esiintyy Suomessa pohjanlepakoilla, isoviiksisiipoilla, vesisiipoilla ja viiksisiipoilla. Tutkielmassa esitellään ensimmäinen pohjanlepakon beetakoronaviruslöytö. Tämä virus ryhmittyy fylogeneettisissa puissa samaan haaraan muiden saman lepakkosuvun kantamien beetakoronavirusten kanssa ja on samalla melko läheistä sukua MERS-koronavirukselle. Tutkielmassa esitellään myös ensimmäinen isoviiksisiipan koronaviruslöytö, joka fylogeneettisten analyysien perusteella ryhmittyy samaan fylogeneettisen puun haaraan luxemburgilaisen ruskosiipan alfakoronaviruksen kanssa. Eniten koronaviruksia löydettiin vesisiipoilta, jotka suurimmalta osin ryhmittyivät samaan fylogeneettisen puun haaraan. Merenkurkussa sijaitsevasta Mustasaaren kunnasta kerätystä vesisiipan ulostenäytteestä löydetty sekvenssi kuitenkin sijoittui erilleen muista suomalaisista sekvensseistä ja eteläisestä Euroopasta todettujen sekvenssien joukkoon, mikä voi viitata tämän alueen lepakkopopulaation ja sen kantamien virusten levinneen Suomeen läntistä reittiä. Tutkielman tulokset luovat hyvän pohjan jatkotutkimuksille, joissa voidaan selvittää virusten tarkempaa esiintyvyyttä sekä niiden tarkempia ominaisuuksia.
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(2024)Lichens are symbioses between fungi, photosynthetic algae and other organisms. The fact that several different fungi may occur in the same lichen thallus adds a further dimension to the diversity of these miniature ecosystems. Calicioids are a polyphyletic group of predominantly lichenised fungi which includes many species with stalked ascomata, topped with a persistent spore mass (mazaedium). One such species is Chaenotheca chrysocephala, a relatively common crustose lichen with a wide distribution. The lichenicolous fungus Chaenothecopsis consociata grows on the thallus of C. chrysocephala and is generally considered to be a parasite. This study aims to map the temporal and geographical distribution of C. chrysocephala and C. consociata in Europe in order to find out whether the parasite was present there before the year 1942, when the species was described, and to identify possible patterns which may affect the population dynamics of these two species. This study found that C. consociata was indeed present in Europe before 1942, at least in Norway, Sweden and Finland. Additionally, the percentage of infected C. chrysocephala thalli seems to have increased in Europe since the parasite was first found. The GBIF dataset showed a significant increase in infected C. chrysocephala thalli in northern Europe (N-EU) compared to central-southern Europe (CS-EU). Although the exact reason is unclear, this increase may be related to differences in forest structure across Europe. Firstly, the host lichen seems to prefer Picea and Pinus as its substrate, these being typical trees of needleleaf forests in Europe. Furthermore, the decrease of old-growth forest stands in Sweden and Finland may have reduced suitable habitat for the host, while the concurrent increase of disturbed stands may have favoured the dispersal of the parasite.
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(2021)Lake ecosystems are shaped by water chemistry processes that affect the lake environment and the species communities within. Changes in the water chemistry thus have far-reaching consequences. Water colour is one variable that affects water chemistry and stems from humic substances in the water. Dark water reduces light availability and also affects nutrient and oxygen availability. A trend of brownification of freshwater systems has been observed in recent years and it is expected to influence species community’s diversity and composition. The aim of this thesis was to study whether brownification is an ongoing issue in the study lakes and whether it has had a negative effect on phytoplankton diversity and resulted in shifts in the phytoplankton composition. A data set including about a 100 lakes in Finland with measurements from 1965 up until now served as the study system which was analysed with statistical methods. The results indicated a brownification trend in the past decades. The brownification so far had a positive impact on species richness but a negative impact on beta diversity. Brownification also affected species composition. Flagellates and autotrophic species increased in darker waters but mixotrophic species that are known to dominate in dark water colour, did not show a clear increase with water colour. Other hydrological variables than water colour could have had a bigger impact on the phytoplankton community than water colour but future monitoring of the phytoplankton community is recommended to see if water colour will have a negative impact on species diversity in the future.
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(2021)Birdsong is information, communication and a target of sexual selection. Song complexity is the variation in bird song structure. Within-song complexity is variation in song components, in number and order of syllables and phrases. Song complexity is an honest trait under sexual selection and competition for mates increases it. When species expands its range front to a new area, the population density is low in the beginning. Males in the new population do not need to compete as hard as before, because population density is decreased, which decreases song complexity. Many warblers have complex songs and they do not have a colourful plumage. It is well possible that song complexity is the main target of sexual selection in warblers. The purpose of this study was to investigate if there were differences in song complexity in Eurasian reed warblers (Acrocephalus scirpaceus) breeding at their range front in Finland. The population of Finland is 100 years old and the population density is still decreased in compared to Central Europe. My hypothesis was that reed warblers would sing less complex songs at lower densities as competition for mates is low. I used song recordings of 51 reed warbler males, which I recorded during the breeding season 2019 in song complexity analyses. Recordings were from South Finland from 14 locations in 6 municipalities. Most of the recording places were coastal reedbeds. A couple of recording places were reedbeds in inland ponds and reedbeds in a flooded forest. I counted the male densities within 50 m and 200 m radius around the recorded males using Google Maps. I took account the males which were at least 20 m away from each other and were there in the same week than the recorded male. I extracted four within-song complexity variables from the recordings: Total number of syllables, number of syllable types, number of syllable transitions and mean frequency bandwidth. I measured song complexity with spectral analyses using Koe, a bioacoustic software. I did next analyses with R to see if there is association between local density and complexity. I found that one of the song complexity variables, total number of syllables, was significantly positively associated with the density of singing males within 200 m radius. The other variables were not significantly associated with male density, but number of syllable types and number of syllable transitions showed a similar relationship with singing male density within 200 m. Previous studies support the hypothesis that higher local density can increase some aspects of song complexity, for example number of syllables or length of phrases. Some males did not have neighbours within 50 m. Density within 50 m had no significant relationship with song complexity variables. However, mean frequency bandwidth, total number of syllables and number of syllable types showed more variation when neighbours were present, which suggest that males increase their effort when they have competition. Finally, I found that the number of syllable transitions decreased as the breeding season progressed. This could be explained with younger birds coming to breed later or with paired males singing less.
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(2021)The general structure of the vertebrate brain is highly conserved. However, a large amount of variation exists in brain size and shape, both regarding the whole brain and its subdivisions. This variation is caused by selection acting on species’ behavioural traits and shaping the evolution of the brain in the same process. It is known that one of the factors affecting vertebrate brain morphology is ecology, including habitat complexity, activity patterns and diet. The effects of diet on brain size have been studied in primates, bats and small mammals, where frugivory in primates and bats and insectivory in small mammals, are linked to larger brains. The effect of diet on brain morphology has not been studied in squamate reptiles (lizards and snakes) and the ecological factors behind size and shape variation are largely unknown in squamates compared to other vertebrates. Squamates show large diversity in diet preference as well as feeding behaviour in general, which makes them a suitable model organism to study brain evolution. Further, squamates have highly developed nasal chemical senses that are important for feeding behaviour. These factors in mind, it would be expected that diet has an effect on squamate brain morphology, and especially the brain regions important for feeding behaviour, such as the olfactory bulbs in the forebrain. To study the effects of diet on squamate brain size and shape, the brains of 51 squamate species were micro-CT scanned and 3D-brain surfaces were generated for each species. The species were categorized into four diet groups: carnivorous, herbivorous, omnivorous and insectivorous. To analyse shape and size change across species and diet groups, 73 landmarks were placed on each 3D-brain surface, covering all brain regions: olfactory bulbs, cerebral hemispheres, telencephalon, diencephalon, midbrain, cerebellum and hindbrain. The results from this study show that diet affects significantly the shape of the whole squamate brain, as well as the size of the telencephalon. Telencephalon size differed significantly between the herbivorous and carnivorous groups. Diet had no significant effect on the other brain subdivisions studied here, including the olfactory bulbs. Diet is a large part of a species’ ecology and it is very complex behaviour involving several senses and brain regions, which could explain the results obtained from this study. The results from this study are preliminary, but they indicate that diet could be one of the factors affecting brain morphology in squamates. In the future, including other factors of feeding behaviour than food choice and analysing the effects of diet on a deeper level, such as including brain regions within the brain and analysing cellular organization, could shed some new light on how diet affects squamate brain morphology.
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(2020)Anthropogenic activity has enhanced global warming at alarming rates, causing temperatures to increase and heat waves to occur more frequently. The effects of global warming are prominent in aquatic ecosystems, particularly in the Baltic Sea. Temperature increases and fluctuations in the Baltic Sea create a changing environment and this can affect inhabiting species’ behaviors, specifically behaviors during reproduction. Reproductive behavior influences both the number and quality of offspring born into a population therefore making behavior changes during reproduction important to study. The three-spined stickleback (Gasterosteus aculeatus), an ectothermic animal, inhabits the Baltic Sea and is an ideal species to study reproductive behavioral changes. Although previous studies have researched three-spined sticklebacks in changing environments, none had specifically looked into the effects of rising temperatures and temperature fluctuations on male three-spined stickleback reproductive behavior. The three-spined stickleback is of particular interest because it reproduces in shallow waters which tend to be more affected by temperature changes. In this study, I aimed to investigate behavioral responses of stickleback males to higher temperatures and to temperature fluctuations during reproduction, as well as the consequences the responses have for reproductive success and the viability of offspring. In order to see how this species would cope with rising temperatures and heat waves during reproduction, a comparative climate chamber experiment was executed in Southern Finland at Tvärminne Zoological Station. Males were housed in either 19°C or 14°C for two breeding cycles, and for the second breeding cycle eight males switched temperatures to experience a temperature fluctuation. Results show that during reproduction, three-spined sticklebacks respond to higher temperatures with increased courtship activity, increased parental activity, quicker breeding cycles, and more weight lost. Parental care activity in constant high temperature decreases from the first to the second breeding cycle, while parental activity in constant low temperature increases. During temperature fluctuations, males experiencing a rise in temperature increase their parental care activity, while males experiencing a drop in temperature demonstrate the opposite. However, no significant consequences of temperature and temperature changes for reproductive success and the viability of offspring were detected during the two breeding cycles. Overall, the results of this study would indicate that the three-spined stickleback will prove to be a resilient species, and maintain population growth in the face of increased temperatures and temperature fluctuations in the Baltic Sea.
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