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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.

Diabetic ovarian cancer patients who take metformin as part of their anti-diabetic medication generally respond better to DNA-damaging cancer treatment. The molecular mechanisms of the anti-cancer effects of metformin are currently being investigated, but they remain poorly elucidated. Not much is understood about the metformin effect on DNA damage in ovarian cancer cells, where it is of particular importance. When chemotherapy-induced double-stranded DNA breaks are unrepaired, cells reach a point when they cannot tolerate the accumulated DNA damage and die. However, some ovarian cancer cells efficiently employ DNA repair mechanisms, the most prominent being homologous recombination (HR), to overcome DNA damage. Efficient HR causes chemoresistance. An important question is whether metformin has the ability to induce the HR-deficient state in cancer cells, thereby sensitizing them to treatment. This study did not examine HR directly, but it assessed HR indirectly by observing the effect of metformin on recovery from DNA damage in two ovarian cancer cell lines: OVCAR4 (HR-proficient) and Kuramochi (HR-deficient). Additionally, this study evaluated the metformin effect on cell proliferation and apoptosis. OVCAR4 and Kuramochi cells were exposed to varying metformin concentrations (0,5 mM, 5 mM, 10 mM, 15 mM, 20 mM and 25 mM) and for varying durations (24 hours and 48 hours). This study also tested how metformin pretreatment affected the cells’ ability to repair externally (ionizing irradiation) induced DNA damage. The cells were imaged with a high-content imaging system, and percentages of nuclei that were positive for markers for different cellular processes (i.e., DNA damage, proliferation, and apoptosis) were calculated. The study found that only high metformin concentrations, such as 20 mM were able to increase DNA damage and reduce cell proliferation in HR-proficient OVCAR4 cells, both non-irradiated and irradiated. The HR-deficient Kuramochi cell line was generally more sensitive to metformin, particularly with regards to DNA damage, which increased using metformin concentrations < 20 mM. However, 20 mM concentration resulted in the most significant effects. Similarly, only high metformin concentration (25 mM) increased apoptosis, although data were obtained only for a limited number of Kuramochi cells. More experiments on apoptosis would be beneficial. Also, more extensive experiments for the irradiation part are needed to validate these preliminary findings, as well as examining whether high metformin concentrations (> 20 mM) affect specifically the HR-mediated DNA repair pathway.

Kainate receptors (KARs) are glutamate receptors that modulate neurotransmission and neuronal excitability. They assemble from five subunits (GRIK1-5 or GluK1-5) present at both pre- and postsynaptic membranes. KAR function is regulated by neuropilin and tolloid-like (NETO) proteins, which also regulate postsynaptic GRIK2 abundance. Some KAR subunit gene variants associate with psychiatric disorders. Moreover, Grik1, Grik2 and Grik4 knock-out (KO) mice display changes in anxiety- and fear-related behaviours. In previous work, Neto2 KO mice expressed higher fear and impaired fear extinction in the fear conditioning paradigm. We hypothesised that this phenotype could be due to reduced KAR subunit abundance in fear-related brain regions, i.e. ventral hippocampus, amygdala and medial prefrontal cortex (mPFC). We specifically investigated GRIK2/3 and GRIK5 levels in the subcellular synaptosomal (SYN) fraction using western blot. We did not observe any difference between genotypes in any of the brain regions. However, our statistical power may have been insufficient, particularly for amygdala and mPFC. Also, an effect on synaptic KAR subunit abundance might be specific to either pre- or postsynaptic compartment, and thus more difficult to detect in SYN fractions. Alternatively, NETO2 absence may affect KAR actions instead of their subunit levels in fear-related brain regions, which could be examined through electrophysiological recordings. Ultimately, unravelling how a molecular system without NETO2 gives rise to fear behaviour in mice may lead to a better understanding of fear-related disorders in human and to new therapeutic strategies.

Agroforestry is a collective name for land-use systems and technologies where woody perennials are deliberately used on the same land-management units as agricultural crops and/or animals. Silvopasture is a type of agroforestry that integrates trees, livestock, and forage crops on the same piece of land. This topic is specifically interesting because silvopasture is already present in Finland, mostly in the form of traditional biotopes, despite these being endangered habitats. Agroforestry is also recognized by the Kyoto Protocol as an afforestation practice that has several advantages. These include environmental benefits, increased productivity, and animal welfare. However, there has been discussion on detrimental effects of animal presence to the trees as well. This research aims to explore the effects of silvopasture on trees, cattle, and the environment in South-western Finland traditional biotopes. Several individual criteria are assessed in three categories: woodland, animal performance and biodiversity. Data was collected on three farms on four pastures through field surveys and farmer interviews. The data is analyzed through multi criterium decision analysis (MCDA) with normalized values from agriculture and forestry to assess performance of silvopastures on three separate categories. Results from four pastures follow a somewhat similar pattern but variation occurs. High scores of forest indicators are reached in woodland category whereas biodiversity category results are lower. Silvopasture negatively affects forest regeneration but otherwise does not have adverse effects. Cattle performance is positive outcome whereas biodiversity category has room for improvement. To get more accurate and comprehensive results the research should be conducted during growing season and with several farms around Finland. However, silvopasture is a meaningful measure to diversify habitats, contribute to animal wellbeing and strengthen ecosystem services.

Fear has far-reaching physiological and behavioural effects for animals, altering their foraging efficiency, parental care and breeding success. Extensive research shows that an animal’s perceived risk of predation, for example, can have fitness effects equivalent to direct killing. However, less work has explored the effects of fear induced by other natural enemies. Here I investigated by field experiment how the perceived risk of brood parasitism by common cuckoos (Cuculus canorus) affects behaviour of reed warblers (Acrocephalus scirpaceus), one of the favourite host species. Previous work shows that reed warblers upregulate behavioural defences based on social information about parasitism risk, but it is not known whether this alters their behaviour outside of an encounter with a cuckoo. Therefore, I manipulated social information about parasitism risk using models and alarm-call playbacks, and measured differences in vigilance behaviour depending on the amount of social information provided (high, medium, low, no risk). I found that vigilance increased when the perception of parasitism risk increased, both during social information presentations and 6 days later during incubation (when the nest is no longer at risk of parasitism). The findings suggest that when perceived risks are high, incubation behaviour is adapted to reduce parasitism risk. Additionally, the cues indicating increased parasitism risk reduced the fledging success, possibly due to the increased stress and the time allocated into vigilance rather than parental care. Therefore, these changes in incubation behaviour impact individual fitness. Further study is required into the behavioural changes in parenting during chick rearing from the increased perception of parasitism risk.

Kiihtyvän ilmastonmuutoksen aikana on entistä tärkeämpää löytää tapoja vähentää päästöjä ja sitoa hiiltä. Biohiilen käyttö on yksi keino ilmastonmuutoksen hillitsemiseen, ja sillä on potentiaalia parantaa maatalouden satoja. Ennen kuin biohiilen käyttö voi yleistyä, sen mahdolliset ulkoisvaikutukset, kuten vaikutukset maaperän eliöstöön, on kuitenkin ensin selvitettävä. Tässä opinnäytetyössä tutkittiin biohiilen käytön vaikutuksia mikrobien suhteelliseen runsauteen, kastematoyhteisöihin ja mikrobibiomassaan. Vain lauhkean ja boreaalisen vyöhykkeen kenttätutkimukset olivat osana tutkimusta. Biohiilen vaikutukset mikrobiryhmien suhteelliseen määrään selvitettiin kirjallisuuskatsauksella. Kirjallisuuskatsaus tehtiin myös selvittäessä biohiilen vaikutuksia kastematoihin. Biohiilen vaikutukset mikrobibiomassaan selvitettiin meta-analyysillä. Meta-analyysissä käytetyt tutkimukset luokiteltiin muuttujien, kuten biohiilen raaka-aineen, pyrolyysilämpötilan, maaperän pH:n, SOC:n, maaperän rakenteen ja biohiilen levitysmäärän perusteella. Tätä kautta voitiin selvittää, voisiko jokin näistä muuttujista selittää meta-analyysin tulokset. Mikrobien suhteellisen runsauden havaittiin muuttuvan biohiilen lisäyksen myötä, mutta reagoivat organismiryhmät vaihtelivat suuresti ja vaikutus yleensä haihtui ajan myötä. Biohiilen lisääminen ei vaikuttanut kastematoihin merkittävästi. Meta-analyysien tulokset viittaavat siihen, että biohiilellä ei myöskään ole merkittävää vaikutusta mikrobien kokonaisbiomassaan. Eri muuttujilla tehdyt meta-analyysit viittaavat siihen, että biohiilen lisäyksellä on positiivisin vaikutus mikrobien biomassaan happamissa maaperissä, joissa on karkea rakenne ja korkea SOC-pitoisuus, kun biohiiltä tuotetaan 500 °C–700 °C:ssa ja levitetään määrinä, jotka ovat suurempia tai yhtä suuri kuin 30 t ha-1. Biohiilen raaka-aineella ei havaittu olevan merkittävää vaikutusta. Yhteenvetona voidaan todeta, että mikrobi- ja kastematoyhteisöt pysyvät yleensä vakaina biohiiltä käytettäessä. Tämä mahdollistaisi biohiilen käytön mm. hiilen sitomiseen ja maaperän hedelmällisyyden lisäämiseen maaperän eliöstöä vahingoittamatta. Lisätutkimusta kaivataan kuitenkin erityisesti boreaalisilla alueilla sekä biohiilen ja pääviljelykasvin mahdollisista vuorovaikutuksista. Tutkia kannattaisi myös mahdollisuuksia käyttää biohiiltä yhdessä muiden orgaanisten käsittelyjen, kuten lannan tai kompostin kanssa biologisen monimuotoisuuden ja sadon parantamiseksi.

Sex determination in humans occurs via the sex chromosomes, X and Y. Females carry two X chromosomes while males are XY individuals. Due to this X chromosome distribution the expression of X-linked genes is balanced with a process called X chromosome inactivation (XCI) where one of the X chromosomes is silenced, selected either randomly or preferentially, in early female embryogenesis. X-linked disorders are more prevalent in males as, generally, in females the effects of a disease-causing variant in other of the X chromosomes can be compensated with the normal allele on the other X whereas male express the allele on their only X chromosome. However, cases of heterozygous females manifesting an assumed recessive X-linked disorder have been reported although the symptoms are usually milder in these cases than in males. One suggested reason behind this is a skewed XCI where the majority of female’s cells express the mutated allele. The main goal of this thesis was to examine how often heterozygous female carriers have symptoms of X-linked disorders. To achieve this goal, likely pathogenic and pathogenic X-chromosomal variants were retrieved from the ClinVar database and their global allele frequencies were examined from The Genome Aggregation Database (gnomAD). The genetic and phenotypic data of 500,000 individuals from the UK Biobank (UKB) were used to conduct genetic association analyses between the ClinVar variants and quantitative traits related to their reported phenotypes. The associations were tested in males and in females separately to allow for examination of sex-specific effects and inheritance models via the comparison of effect sizes. 89 (likely) pathogenic variants were detected from UKB, and the majority of these were extremely rare with minor allele frequency below 0.01% in the global population. 11 and 27 of them were selected for the association analyses for the male and female populations of UKB, respectively, after filtering out variants that did not meet requirements such as enough carriers. One to five quantitative traits were chosen for each variant resulting in 28 tests among males and 87 among females. These analyses showed few significant associations while the majority of the tested variants were observed to have no effects on the chosen trait. The most statistically significant association was observed with variant rs137852591 on the gene AR (androgen receptor) in males. The variant was related to lower muscle mass and shorter height that are associated partial androgen insensitivity syndrome reported in ClinVar for this variant. Nominally significant associations were seen with this variant and the same traits in heterozygous females suggesting that there might be, indeed, symptoms of the syndrome in females as well. Additionally, in both sexes variants on gene G6PD seemed related to traits that are characteristics of glucose 6 phosphate dehydrogenase deficiency. The limitations of these databases must be taken into account when conducting studies utilizing them. However, this thesis demonstrated that heterozygous female carriers may have symptoms of X-linked disorders assumed to have recessive inheritance pattern. In the future, a wider set of phenotypes could be used to investigate the impacts of the X-linked variants more broadly.

The non-lethal effects of predation, i.e. predation risk, can significantly affect the prey population by inducing changes in behavior to reduce the risk of predation. Vigilance, hiding, and fleeing are common responses in order to lower predation risk while changes in habitat selection, habitat use, and changes in activity patterns are more severe changes and can profoundly affect prey fitness. Prey may begin to avoid habitats frequented by predators and may begin to reduce their activity during the time of day when predators are active. Human disturbance can be comparable to predation risk as it may induce similar changes in behavior. Therefore, human activity can be compared to predation risk even though the risk posed by humans may rarely be lethal. For many large vertebrates, however, humans do pose a direct and lethal threat. This is especially true for large predators whose severe decline has been attributed to centuries of persecution and habitat loss and whose populations have only recently began to increase following more favourable management plans and conservation efforts. Similarly, brown bear (Ursus arctos) populations have only recently began to increase in many parts of Europe and North America. In Finland brown bears survived extinction only in the wilderness areas in the north and in the east but have recolonized much of the country in the past decades. These solitary, opportunistic omnivores prefer forested habitats and usually try to avoid humans who they may view as predators. The limited availability of ideal habitats and extensive human activity means that bears may have to use spatio-temporal avoidance of humans rather than large scale spatial avoidance in order to reduce the risk of encountering humans. This should be evident in bear daybed selection whereby bears should select daybed sites away from human activity and select sites that provide good cover against humans while the bear rests during the day i.e. peak period of human activity. Additionally the daybed concealment should be higher closer to human activity. I studied bear daybed selection using GPS location data from collared bears from Central Finland and North Karelia regions and identifying possible daybed sites. Habitat of the daybeds was studied both by visiting daybeds in the field to assess the tree height, tree species composition, and concealment (visibility and canopy cover) and by using GIS software to identify large scale habitat preference. Effects of human activity (house, small roads, large roads) were studied by comparing the concealment of the daybed to a nearby random site and by comparing the bears' early morning locations' distance to human activity with subsequent daybed locations. Further tests were performed to test if season, bear sex, or the study area affected bear daybed selection. The results indicate that bears strongly preferred forested habitats in daybed selection and preferred mixed forests and woodland shrub habitat over the dominant coniferous forests possibly due to their higher proportion and availability of spruce (Picea abies) and deciduous trees (e.g. Betula spp. and Populus tremula) that can offer better cover than pine (Pinus sylvestris) which is dominant in coniferous forests. Mixed forests and woodland shrub may also be preferred as they provide bears with more nutritious vegetation as a food source. Both males and females preferred sites with shorter trees for better concealment while females with cubs preferred sites with taller trees with less concealment. Thus females with cubs may have to trade high concealment for better escape chances for the cubs to avoid potentially infanticidal males. Human activity was shown to affect daybed selection as daybed sites were more concealed than nearby random sites and bears were also closer to human activity during early morning but selected their daybeds farther away. Daybeds were considerably farther away from houses and large roads than from small roads which were often scarcely used forestry roads. Concealment did not change with distance to human activity indicating that bears may not be able to avoid human activity at a large spatial scale even in areas of low human population density. Due to low sample sizes and individual bias the results of this study should be considered more indicative than of high probability. Nevertheless they provide largely new information on bear daybed selection that may be of public interest in reducing human bear conflicts and of use in bear conservation and management.

The gut microbiome of mammals plays many important roles in the host, including preventing colonization of pathogens, maintaining intestinal homeostasis, helping digest nutrients and even affecting host behavior. The composition of mammalian gut microbiota varies greatly between individuals, species and in time. When a mammal is born, it acquires its first, mostly anaerobic, gut microbiota through maternal transmission in the birth canal. After the initial transmission of bacteria, host genotype, especially genes related to immunity, become an important factor that helps determine which species get to stay in the gut and prosper. In adulthood age, sex, diet, disease and contact with others all become important shapers of microbiome composition. Since microbial communities are comparable to any macroecological communities, they can be explained through ecological theories. For example, community assembly theory can help distinguish the effects of input (e.g. transmission) from selective processes (e.g. filtering host genotype) on gut microbiome composition. Community assembly can lead to multiple stable equilibria determined by which species colonized the area first (“priority effect”), emphasizing the importance of early transmission, such as that maternal transmission birth. Metacommunity theory on the other hand, views a large ecosystem as a mosaic of patches and can be helpful in describing the composition of the microbiome in adult individuals. In this thesis, I use community assembly theory and metacommunity theory as a framework to explore determinants of individual gut microbiome composition in wild European wood mice (Apodemus sylvaticus). Specifically, I set out to investigate how much of the gut microbial community variation was accountable for host relatedness and how much of this effect is due maternal transmission (input) versus host genotype (filtering). To find out more about what affects the composition of the gut microbiome in wild animals, I collected both tissue and microbiome samples from wood mice in the Wytham woods research area near Oxford, Great Britain. In addition to the data collected in Wytham, I was given another similarly collected dataset from Silwood Park. My study questions were: What proportion of gut microbiome composition in wood mice is determined by host genotype? Do mothers affect their offspring’s microbiome more than fathers through maternal transmission of bacteria? DNA extractions and mouse genotyping were done by me in the MES laboratory at the University of Helsinki. Sequencing of microbial DNA was done by my co-supervisor at Royal Veterinary College in London. Microbiome similarity was compared to host genetic relatedness using Mantel test and likelihood ratio tests on linear models with dyadic data (comparing relatedness and microbiome similarity of each pair). According to the results, related individuals had a significantly more similar microbiome in Wytham, but not in Silwood. In both populations, microbiome similarity was also affected significantly by age and home range area. The general trend was, that mother-pup and fullsib pairs had more similar microbiome than unrelated pairs (though this effect was significant only in Wytham) and father-pup pairs had a more different microbiome than unrelated pairs (though this effect was significant only in Silwood). All data combined, mice had significantly more similar microbiome with their mother than father. The higher similarity between mother-pup pairs and full siblings can be explained by maternal transmission and postnatal physical contact. Since the father’s effect is purely genetic, their microbiome differing from their offspring even more than from unrelated individuals could be explained by lack of physical contact and different age. Alternatively, females could even be choosing to mate with males with different immunogenotypes, and thus more different microbiome from themselves than expected by chance. Based on my results, transmission of bacteria during and shortly after birth is a key factor shaping microbiome composition and it might even account for the “genetic” effect seen in previous studies.

Suot ovat tärkeä osa maailmanlaajuista hiilen kiertokulkua, koska ne varastoivat suuria määriä hiiltä eloperäiseen materiaaliin turpeen muodossa, joka muodostuu biomassan hitaasta hajoamisesta kylmän, hapettoman ja matalan pH:n ympäristön vuoksi. Soista vapautuu myös metaania (CH4), joka on voimakas kasvihuonekaasu, jonka lämmityspotentiaali on 28 kertaa voimakkaampi kuin hiilidioksidin (CO2). Turvemaiden netto-C-päästöt riippuvat suotyypistä ja ympäristöolosuhteiden muutoksista, kuten pohjaveden korkeudesta tai turpeen lämpötilasta, ja niistä johtuvasta tasapainosta CH4-päästöjen ja turpeen muodostumisesta johtuvan hiilinielun välillä. Tämän tutkimuksen tavoitteena oli selvittää, miten kasviyhteisöt ja muut säätelevät tekijät, kuten lämpötila, pohjaveden korekus, LAI ja suotyyppi vaikuttavat sekä ilmakehän hiilivirtaan että turpeen CH4- ja CO2-pitoisuuksiin. Lisäksi tehtiin stabiiliin hiili-13 isotoopin mittauksia, jolla saadaan lisätietoa metanogeneesin biogeokemiasta. Mittaukset otettiin rahkasammalvaltaisista mättäistä ja saravaltaisista välipinnoista. Mittauspisteille tehtiin kolme kasvillisuuden manipulointia, joilla selvitettiin kasvillisuuden vaikutuksia hiilidynamiikkaan 1. putkilokasvien ja sammaleiden poisto, 2. pelkkä putkilokasvien poisto, 3. Kaikki kasvillisuus tallella. Tutkimuspaikka sijaitsee Etelä-Suomessa Siikanevan suoalueella. Mittaukset tehtiin vuonna 2018 touko-syyskuussa ombrotrofisessa keidasrämeessä ja oligotrofisessa saranevassa. Mittauskausi oli poikkeuksellisen kuiva ja pohjavedenkorkeus oli keskiarvoa matalammalla. Tästä johtuen monia aikaisemmin havaittuja korrelaatioita ei löytynyt. CH4-virtojen suuruus riippui suotyypistä ja kasvillisuuden manipuloinnista. Keskimääräiset turpeen CH4 ja CO2 pitoisuudet olivat hieman korkeammat mittauspisteissä saranavevalla. Pitoisuudet kasvoivat nopeasti syvyyden myötä, 50 cm:n syvyydessä pitoisuudet olivat useita suuruusluokkia suurempia kuin 7-20 cm:n syvyyksissä korkeimpien, mittausten ollessa yli 500 000 ppm. δ13C-CH4-arvot muuttuivat negatiivisemmiksi tyypillisesti syvyyden myötä, kun hydrogenotrofinen metanogeneesi yleistyi. Kasvillisuuden manipuloinneilla oli vaihtelevia vaikutuksia CH4-vuohon, eikä lehtipinta-alaindeksi osoittanut vahvaa lineaarista korrelaatiota CH4:n kanssa. CH4-virtaus oli myös epäherkkä pohjaveden korkeudelle, mutta kasvien välittämä CH4-kuljetus ei todennäköisesti ollut syynä, koska kasvillisuuden poistokäsitellyt mittauspisteet osoittivat myös samanlaista epäherkkyyttä veden korkeudelle. Putkilokasvien ja sammaleiden poistaminen vähensi yleensä CH4-virtoja. Mättäissä, joissa putkilokasvit oli poistettu, mutta sammaleita ei, oli alhaisimmat CH4-virrat. Yhteenvetona voidaan todeta, että useimmat ympäristömuuttujat eivät osoittaneet vahvaa korrelaatiota CH4:n kanssa. Mikään yksittäinen muuttuja ei selittänyt selvästi eroja CH4-vuossa. Turpeen CH4 ja CO2 pitoisuudet riippuvat voimakkaasti syvyydestä ja suotyypistä. Kasvillisuuden poistaminen tyypillisesti vähensi CH4-virtoja.