Phenotypic plasticity is the ability of an organism to express different phenotypes depending on the biotic or abiotic environment. In many cases, the response to the environment is beneficial to the individual and can therefore represent adaptive phenotypic plasticity. An example includes morphological and life-historical response to predators. Because there has been a weak interest in the effect of these morphological changes, and it often assumes, but rarely shown, that predator-induced changes are adaptive. I tested how different variables, such as maximum acceleration and velocity, were related to each other in different Gosner stages. Eggs and tadpoles of the species Rana temporaria were exposed to various predator enclosures, a control, a stalking predator (European Perch, Perca fluviatilis), and an ambush predator (dragonfly larvae). The tadpoles mean weight, maximum acceleration and velocity, mobility, boldness, and morphological changes in various Gosner stages were analyzed. My tests showed a significant difference in tadpole weight and their morphology, however, there were no differences in speed, acceleration, boldness or mobility. The morphometric analysis of the tadpoles showed a significant change of tadpoles in the perch treatment compared to the tadpoles in the control. The tadpoles in the perch treatment showed a higher TH/TL (tail height/tail length) ratio, and were overall heavier, than the tadpoles in the control, but no significant change compared to the tadpoles in the dragonfly treatment. This shows that the kairomones and alarm cues triggered a large morphological change, but the effect of the change requires more research.

Migration occurs among many animal species for the purpose of, among other things, finding food or to reproduce. Spawning migration is a form of migration that occurs among many fish species where they move to another site for reproduction. The movement can be obstructed by migration barriers like road culverts. Barriers to migration pose one of the greatest threats to biodiversity and ecosystem functions in freshwater. They impair the connectivity of watercourses and may prevent fish from improving reproductive success or completing their life histories altogether. There are both benefits and costs with migration, benefits such as increased survival for the adults and offspring, and costs such as increased energy consumption and increased mortality. The costs are often dependent on the morphological traits of the individual, like body shape and size. In this study, the spawning migration of two species of fish of the family Cyprinidae, ide (Leuciscus idus) and roach (Rutilus rutilus) was investigated. Few studies have been made on ide or on roach compared to other cyprinids and salmonids. This study might therefore enhance the overall knowledge of these two species. The overall aims of this project are to study and compare phenotypic correlates of spawning migration behaviour of ide and roach. The field studies were performed in Oknebäcken, Mönsterås (SE632310-152985), Sweden in March and April 2020. To describe the watercourse and define the location and characteristics of different potential migration barriers, a simplified biotope mapping method was used. The fish were caught in a hoop net and then measured, weighted, sexed, and injected with passive integrated transponder using the bevel down method. In order to register in stream movement of fish, reading stations with antennas were placed, at two locations upstream from the marking station and one downstream at the estuary. The sex ratio differed from the expected 1:1 with a majority of females for both species. This might be a result of fluctuations in survival of spawn coupled with different age-at-maturity between sexes. We found that individuals that arrived early to the stream were larger for both study species, as other studies also reported. Also, male ide was both larger and arrived before female ide. There might be an energy cost associated with early arrival to the stream and therefore, larger individuals arrive first. For roach, there was no difference in arrival time between the sexes although female roach were larger. There was no difference in the time spent in the stream between the species. For ide, females stayed for a longer period of time in the stream than males. However, the opposite was true for roach. This may be because male roach might benefit from more fertilization events when staying longer. There might therefore be a trade-off between the energy cost in staying in the stream and the increased fitness advantage in fertilization events. We found no correlation between any of the morphological traits and migration distance. However, since very few individuals were registered at the upstream reading stations, there might be an effect of migration barriers on the spawning migration. The mortality after spawning was higher for roach than for ide. For ide, a larger proportion of females than males died. For roach, individuals that arrived early was classified as alive to a greater extent than those who arrived late. Both similarities and differences between the species were discovered in this study which concludes that even closely related species might differ substantially from each other.

Sexual conflict is a term that describes the situation where traits can experience opposing selection pressures in the two sexes. Theory suggests this conflict exists in all organisms with separate sexes, and specific chromosome clusters which are possibly sexually antagonistic have been identified in the species Drosophila melanogaster. One of all identified genes is CG3598, which have proved yielding higher fitness for males carrying allele A2 on this gene compared to A1. In this study, factors which contribute to the difference in fitness between these two alleles, with regards to sperm competition and mating success were observed. A double mating design was used, in which males and females were placed in test tubes together in order to examine the number of copulations and the defensive (P1) and offensive (P2) ability of sperm. The relative fitness of males carrying A1 did not differ from males carrying A2, which rejects previous studies, however, A2 had a higher defensive capability compared to A1. On the other hand, A1 instead had better offensive capability and higher amount of rematings. This indicates that the defensive capability of A2 is very strong and opposes the offensive capability of A1, but also the increased rate of rematings in A1. To get a more precise understanding of the fitness relation between A1 and A2 on the gene CG3598, further experiments would need to be performed on the subject. / Sexuell konflikt är ett begrepp som beskriver förhållandet där egenskaper upplever olika selektionstryck beroende på kön. Teorier finns om att den här konflikten existerar i alla organismer med olika kön, och i arten Drosophila melanogaster har det identifierats specifika kromosomkluster som har möjlighet att bidra till sexuell konflikt. En utav alla identifierade gener är CG3598 som har påvisats ge en högre fitness för hanar bärande allel A2 på denna gen jämfört med allel A1. I den här studien undersöks bakomliggande faktorer till skillnaden i fitness mellan dessa två alleler, med avseende på spermiekonkurrens och parningsframgång. Genom en dubbel parningsdesign, där hanar och honor placerades tillsammans i rör undersöktes den defensiva spermieförmågan (P1), den offensiva förmågan (P2) och antal parningar. Den relativa fitnessen hos hanar med A1 skiljde sig inte från A2, vilket motsäger tidigare studier. Däremot var den defensiva förmågan högre för A2 och A1 hade istället högre offensiv förmåga samt en högre andel omparningar. Detta indikerar att A2 har en stark defensiv förmåga som motsätter den offensiva förmågan i A1 men också möjligheten till fler omparningar. För att få en mer precis uppfattning skulle ytterligare experiment behöva utföras då det i denna studie var en väldigt låg andel hanar som parade sig jämfört med vad som förväntas.

Wing polyphenism in insects is a type of phenotypic plasticity where environmental factors trigger the development of a set of discrete wing morphologies. In the water strider Gerris buenoi, photoperiods are the main environmental cue that trigger wing morph determination. The genetic mechanisms connecting environmental cues and the determination of wing morph in G. buenoi are not clear. However, recent experimental work suggests that engagement of the Hippo pathway via ecdysone signalling is a promising model for further investigation. In this study, a reverse-transcription quantitative PCR (RT-qPCR) protocol was developed, aimed at elucidating this potential transduction pathway by quantifying gene expression of Fat, Dachsous, Yorkie, EcR, E75 and E74. This was done using melt curve analysis, gel electrophoresis, sequencing of RT-qPCR products and qPCR standard curves. Additionally, wing morph distribution in extreme and intermediate photoperiods were examined. Wing morph proportions were significantly different between adults emerging in the intermediate photoperiods 15.30:8.30 and 15:9 (hours light : hours dark). An effect of sex was observed, with a higher probability of males becoming long-winged compared to females. This has likely evolved as a result of a dispersal-reproduction trade-off. Taken together, this study provided insight for future investigations of periodically induced wing morph determination and its genetic mechanisms in G. buenoi that will contribute to the understanding of phenotypic plasticity.

Det är allmänt accepterat att lärare bör använda sig av evolutionsteorin som ett sätt att binda ihop undervisningen i biologi. Åtskilliga studier har dock påvisat att flertalet elever har missuppfattningar och föreställningar inom evolution som motverkar deras inlärning av evolutionsteorin. Det samma gäller för begreppsförståelse och konflikten mellan betydelsen av ett ord i vardagsspråket och i ämnesspråket. Tidigare forskning har också kartlagt att biologilärare inte alltid är medvetna om elevers svårigheter eller utformar en evolutionsundervisning som utmanar elevers begreppsförståelse. Denna kvalitativa studie som genomfördes med hjälp av intervjuer med sex olika lärare visar på samma mönster och pekar på några möjliga lösningar för att förbättra elevers förståelse för de evolutionära mekanismerna.  Samtidigt som det finns en stor samstämmighet bland de intervjuade biologilärarna kring begreppsförståelse, precis som i många andra ämnen, resonerar de olika om vilka delar som är viktiga i evolutionsundervisningen och varför. En del fokuserar mer på att lära ut innehållet enligt den lärobok som används medan en del förklarar mer om varför eleverna ska lära sig om evolution.  Som ett resultat av denna studie föreslås bland annat att undervisningen om evolution borde inledas så tidigt som möjligt för att i största möjliga mån minimera risken för att olika missuppfattningar och föreställningar kring evolution inte ska cementeras tidigt. I detta sammanhang bör också information kring ämneskunskap förmedlas vid överlämningarna från ett stadium till ett annat i grundskolan. Vidare föreslås att användandet av CoRe-verktyget implementeras i planeringen av undervisningen och att det införs som ett moment under VFU- arbetet för blivande ämneslärare. Det faktum att tid är en bristvara för lärare innebär att det sällan finns tid för egen reflektion. Därför måste arbetet med CoRe-verktyget schemaläggas på samma sätt som många skolor idag arbetar med kooperativt lärande.

Methods for estimating past demographic events of populations are powerful tools in order to get insights of otherwise hidden pasts. The genetic data of people is a valuable resource for these purposes as patterns of variation can inform of the past evolutionary forces and historical events that generated them. There is, however, a lack of methods within the field that uses this information to its full extent. That is why this project has looked at developing a set of new alternatives for estimating demographic events. The work done has been based on modifying the purely sequence based method TTo (Two-Two-outgroup) for estimating divergence times of two populations. The modifications consisted of using beta distributions to model the polymorphic diversity of the ancestral population in order to increase the max sample size possible. The finished project resulted in two implemented methods: TT-beta and a partial variant of MM. TT-beta was able to produce estimations in the same region as TTo and showed that the usage of beta distributions had real potential. For MM there only was a partial implementation able to be done, but this one also showed promise and the ability to use varying sample sizes to estimate demographic values.

Sexual antagonistic selection is when an allele is favorable to one sex but harmful tothe other sex. Sexual antagonism is very common in nature and occurs among manyspecies. Although sexual antagonism plays an important part in evolution, today weknow very little about the mechanisms that contribute to this phenomenon and veryfew antagonistic locus have been identified. A study examining Drosophilamelanogaster was conducted to find out which locus was associated with sexualantagonism. Several candidates were identified. One of these candidates was the geneCG3598. This study aims to test and confirm whether there is a sexual antagonisticeffect in the locus of the gene CG3598 as a former study predicted. The hypothesis isthat the two alleles of CG3598 will show a sexual antagonistic effect on fitness. To dothis, two experiments were performed, one for D. melanogaster males and one forfemales. The tests were to measure the difference in reproduction of D. melanogasterbetween the two different allele variants that were previously created using theCRISPR/Cas9 technique in a new wild-type background. The two different variantsfor both males and females mated with wild type variants in separate vials and thenwe counted which allele had managed to reproduce the most. The results showed thatthere was a significant difference between the two alleles for males but not forfemales. This means that one allele was better for male reproduction then the other.However, from this test you cannot conclude what made them better. For thefemales, there was a big difference between the test groups, which was not expectedand suggests that something may have gone wrong during the tests. The conclusion isthat there is a difference in fitness in the two alleles of CG3598 for males, however, itis not possible to confirm the hypothesis of a sexual antagonistic effect. / Sexuell antagonistisk selektion är när en allel är gynnsam för ena könet men skadligför det andra könet. Sexuell antagonism är mycket vanligt i naturen och förekommerbland många arter. Även fast sexuell antagonism spelar en viktig del inom evolutionvet vi idag mycket lite om mekanismerna som bidrar till detta fenomen och väldigt fåantagonistiska lokus har identifierats. En tidigare studie undersökte Drosophilamelanogaster för att tar reda på vilken lokus som var associerad med sexuellantagonism. Dem kom fram till ett flertal kandidater, en av dessa kandidater vargenen CG3598. Denna studie går ut på att testa och bekräfta om det finns en sexuellantagonistisks effekt vid lokusen av genen CG3598 som tidigare studie förutspått.Hypotesen är att dem två allelerna av CG3598 kommer visa en sexuell antagonistiskeffekt på fitness. För att göra detta utfördes två experiment, ett för D. melanogasterhanar och ett för honor. Testerna gick ut på att mäta skillnaden i reproduktion hos D.melanogaster mellan de två olika allel varianter som var tidigare skapade medCRISPR/Cas9 tekniken i en ny vildtyp bakgrund. Jag lät dem två olika varianternabåde för hanar och honor para sig med vild typs varianter i separata provrör för attsedan räkna vilken allel som lyckats reproducera sig mest. Resultatet visade att detfanns en signifikant skillnad mellan dem två allelerna för hanar men inte hos honor.Detta betyder att ena allelen var bättre för hanars reproduktion en den andra. Dockkan man inte från detta test av göra vad det är som gör att dem är bättre. För honornavar det stor skillnad mellan testgrupperna vilket inte var förväntat och tyder på attnågot kan gått fel under testerna. Slutsatsen är att det finns en skillnad fitness hos dettvå allelerna av CG3598 för hanar, dock går det inte att bekräfta hypotesen för ensexuell antagonistisk effekt.

Only 40 years ago, just three individuals made the journey from Finland/Russia to found the current wolf population in the southwest of Sweden. This population, that to this date descends from less than 10 founders, has a substantial increased extinction risk due to inbreeding. Several previous studies have used SNPs to monitor the level of inbreeding and homozygosity in the population, as well as measure immigration and the inflow of new genetic material. This study uses both short- and long-read data to discover structural variants (SVs) and small indels in the population, so that they may be used to extend the analyses and provide more insight into the current state of the Scandinavian wolf population. After the calling of the SVs, strict filtering and manual curation were applied to the data, thereby removing many false positive calls and increasing confidence in the remaining SVs. Short-read and long-read SV-callers found 31,800 and 57,821 SVs respectively, with relatively little overlap between the two sets. By far, the most common SV-types were deletions and insertions, at about 30,000 each with varying length ranging from a 50 base pairs to several tens of Mbp. Analyses on the data, such as PCAs and parent-offspring trio analyses, reveal high-confidence calls and consistent results between SV-types and SV-callers, as well as a low estimated genotyping error rate. PCAs performed on the SVs resembled those performed on SNPs, which strengthens the credibility of the identified variants. Finally, this study suggests several alternative steps for possible improvement to the dataset, along with some proposals for subsequent research topics that may use the variants discovered in this study.