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Animal eyes typically possess specialized regions for guiding different behavioural tasks within their specific visual habitat. These specializations, and evolutionary changes to them, can be crucial for understanding an animal's ecology. Here, we explore how the visual systems of some of the smallest flying insects, fungus gnats, have adapted to different types of forest habitat over time (approx. 30 Myr to today). Unravelling how behavioural, environmental and phylogenetic factors influence the evolution of visual specializations is difficult, however, because standard quantitative techniques often require fresh tissue and/or provide data in eye-centric coordinates that prevent reliable comparisons between species with different eye morphologies. Here, we quantify the visual world of three gnats from different time periods and habitats using X-ray microtomography to create high-resolution three-dimensional models of the compound eyes of specimens in different preservation states-fossilized in amber, dried or stored in ethanol. We present a method for analysing the geometric details of individual corneal facets and for estimating and comparing the sensitivity, spatial resolution and field of view of species across geographical space and evolutionary time. Our results indicate that, despite their miniature size, fungus gnats do have variations in visual properties across their eyes. We also find some indication that these visual specializations vary across species and may represent adaptations to their different forest habitats. Overall, the findings demonstrate how such investigations can be used to study the evolution of visual specializations-and sensory ecology in general-across a range of insect taxa from different geographical locations and across time.

This thesis comprises investigations of microstructures and molecular remains, preserved in a variety of fossil specimens. The results are presented in six papers, collectively aiming to thoroughly examine fossil traces of such remains by employing a combination of both established and relatively new analytical methods. The main questions asked are: What can we learn about the biology, ecology and behaviour of ancient organisms by studying these fossilised remnants, and what methods are best suited to accomplish this?The work presented herein has been conducted through a series of case studies performed on fossils representing an array of taxa, collected from different geological ages and settings. Methods applied include light and electron microscopy, computed tomography, and molecular analyses, such as time-of-flight secondary ion mass spectrometry, IR microspectroscopy and X-ray absorption spectroscopy. Microscopic analysis and histology of teeth from Mesozoic marine reptiles allowed calculations of dentine formation and tooth replacement rates. My findings include evidence that while teeth of larger mosasaur taxa took longer time to develop, their dentine formation rates were more rapid, relative to that of smaller species.In other fossils, microscopic investigations of eye, skin and feather remnants revealed aggregations of micrometre-sized, sub-rounded to elongate structures. Because similar microbodies have previously been described alternatively as relict melanosomes (i.e. pigment-containing, eukaryotic cellular organelles) and lithified bacteria, my co-authors and I performed chemical and molecular analyses in order to explore the affinity of these structures. To ascertain the chemical identity of our fossil samples, corresponding analyses were carried out also on molecularly similar compounds, including modern eumelanin, as controls. My studies show chemical evidence of animal eumelanin in close association with the microbodies, advocating the melanosome i

Feathers are amongst the most complex epidermal structures known, and they have a well-documented evolutionary trajectory across non-avian dinosaurs and basal birds. Moreover, melanosome-like microbodies preserved in association with fossil plumage have been used to reconstruct original colour, behaviour and physiology. However, these putative ancient melanosomes might alternatively represent microorganismal residues, a conflicting interpretation compounded by a lack of unambiguous chemical data. We therefore used sensitive molecular imaging, supported by multiple independent analytical tests, to demonstrate that the filamentous epidermal appendages in a new specimen of the Jurassic paravian Anchiornis comprise remnant eumelanosomes and fibril-like microstructures, preserved as endogenous eumelanin and authigenic calcium phosphate. These results provide novel insights into the early evolution of feathers at the sub-cellular level, and unequivocally determine that melanosomes can be preserved in fossil feathers.

Colour, derived primarily from melanin and/or carotenoid pigments, is integral to many aspects of behaviour in living vertebrates, including social signalling, sexual display and crypsis. Thus, identifying biochromes in extinct animals can shed light on the acquisition and evolution of these biological traits. Both eumelanin and melanin-containing cellular organelles (melanosomes) are preserved in fossils, but recognizing traces of ancient melanin-based coloration is fraught with interpretative ambiguity, especially when observations are based on morphological evidence alone. Assigning microbodies (or, more often reported, their 'mouldic impressions') as melanosome traces without adequately exduding a bacterial origin is also problematic because microbes are pervasive and intimately involved in organismal degradation. Additionally, some forms synthesize melanin. In this review, we survey both vertebrate and microbial melanization, and explore the conflicts influencing assessment of microbodies preserved in assodation with ancient animal soft tissues. We discuss the types of data used to interpret fossil melanosomes and evaluate whether these are sufficient for definitive diagnosis. Finally, we outline an integrated morphological and geochemical approach for detecting endogenous pigment remains and associated microstructures in multimillion-year-old fossils.

Feathers are amongst the most complex epidermal structures known, and they have a well-documented evolutionary trajectory across non-avian dinosaurs and basal birds. Moreover, melanosome-like microbodies preserved in association with fossil plumage have been used to reconstruct original colour, behaviour and physiology. However, these putative ancient melanosomes might alternatively represent microorganismal residues, a conflicting interpretation compounded by a lack of unambiguous chemical data. We therefore used sensitive molecular imaging, supported by multiple independent analytical tests, to demonstrate that the filamentous epidermal appendages in a new specimen of the Jurassic paravian Anchiornis comprise remnant eumelanosomes and fibril-like microstructures, preserved as endogenous eumelanin and authigenic calcium phosphate. These results provide novel insights into the early evolution of feathers at the sub-cellular level, and unequivocally determine that melanosomes can be preserved in fossil feathers.

Feathers are amongst the most complex epidermal structures known, and they have a well-documented evolutionary trajectory across non-avian dinosaurs and basal birds. Moreover, melanosome-like microbodies preserved in association with fossil plumage have been used to reconstruct original colour, behaviour and physiology. However, these putative ancient melanosomes might alternatively represent microorganismal residues, a conflicting interpretation compounded by a lack of unambiguous chemical data. We therefore used sensitive molecular imaging, supported by multiple independent analytical tests, to demonstrate that the filamentous epidermal appendages in a new specimen of the Jurassic paravian Anchiornis comprise remnant eumelanosomes and fibril-like microstructures, preserved as endogenous eumelanin and authigenic calcium phosphate. These results provide novel insights into the early evolution of feathers at the sub-cellular level, and unequivocally determine that melanosomes can be preserved in fossil feathers.

Feathers are amongst the most complex epidermal structures known, and they have a well-documented evolutionary trajectory across non-avian dinosaurs and basal birds. Moreover, melanosome-like microbodies preserved in association with fossil plumage have been used to reconstruct original colour, behaviour and physiology. However, these putative ancient melanosomes might alternatively represent microorganismal residues, a conflicting interpretation compounded by a lack of unambiguous chemical data. We therefore used sensitive molecular imaging, supported by multiple independent analytical tests, to demonstrate that the filamentous epidermal appendages in a new specimen of the Jurassic paravian Anchiornis comprise remnant eumelanosomes and fibril-like microstructures, preserved as endogenous eumelanin and authigenic calcium phosphate. These results provide novel insights into the early evolution of feathers at the sub-cellular level, and unequivocally determine that melanosomes can be preserved in fossil feathers.

Feathers are amongst the most complex epidermal structures known, and they have a well-documented evolutionary trajectory across non-avian dinosaurs and basal birds. Moreover, melanosome-like microbodies preserved in association with fossil plumage have been used to reconstruct original colour, behaviour and physiology. However, these putative ancient melanosomes might alternatively represent microorganismal residues, a conflicting interpretation compounded by a lack of unambiguous chemical data. We therefore used sensitive molecular imaging, supported by multiple independent analytical tests, to demonstrate that the filamentous epidermal appendages in a new specimen of the Jurassic paravian Anchiornis comprise remnant eumelanosomes and fibril-like microstructures, preserved as endogenous eumelanin and authigenic calcium phosphate. These results provide novel insights into the early evolution of feathers at the sub-cellular level, and unequivocally determine that melanosomes can be preserved in fossil feathers.

Title: “Spatiality, function and symbolism - Medieval Scandinavian burial customs with focus on children in churches”. The aim of this master thesis is to shed light upon children buried inside churches. To do this, the author uses spatiality, symbolism, functionality and gender as theorethical perspectives. The material culture comes from seven different sites around Scandinavia. They are connected such a way that both the church and the surrounding cemetery have been excavated. Also earlier research and medieval texts are used as material. The method used in the thesis is comparison. The author wants to see if there are similarities or differences between the different geographical areas but also within each site. The author believes that there are connections between children buried in the churches and those buried in the cemetery, according to the used grave material. But analyzing the children in churches together with the used perspectives, it seems that those children might have been placed in this high status area for many reasons.

The dentine of teeth from five genera of mosasaurs [i.e., Clidastes, Halisaurus, Dollosaurus (Prognathodon),cf. Platecarpus, and Tylosaurus] and a Mesozoic crocodylian (Aigialosuchus) from the Campanian of the Kristianstad Basin, southernmost Sweden, displays two types of incremental growth lines; i.e., von Ebner’s and, for the first time in extinct animals, Andresen’s lines. These lines are homologous to incremental growth lines found in the dentine of extant mammals and reptiles, as well as in the teeth of non-avian dinosaurs and extinct mammal-like reptiles, and are probably homologous for the entire Amniota. The incremental lines document different accumulation rates, where the lines of von Ebner are deposited daily and the Andresen’s lines are deposited roughly every 7–8 day. Incremental lines were measured and counted to obtain replacement rate values for the teeth being analysed. For mosasaurs, the tooth replacement rates varied between 260 (Platecarpus) and 593 days (Tylosaurus), whereas the corresponding rate for the contemporaneous crocodylian Aigialosuchus was 240 days. The dentine accretion rates were similar to one another independent on phylogenetic relationship and tooth-size, to suggest that the tempo was genetically controlled rather than an effect of diet or habits. A replacement tooth was observed growing inside the functional Aigialosuchus tooth, thus providing evidence that tooth replacement was a continuous process where a germ tooth was always ready to replace an older one., Liksom en trädstam uppvisar årsringar som kan användas för att beräkna dess ålder, bildas också tillväxtringar i tänderna hos många djur, även hos dem som regelbundet byter tanduppsättning. Detta fenomen noterades av paleontologen Richard Owen redan i mitten av 1800-talet, men det är först de senaste decennierna som forskningen inom tandersättningscykler hos utdöda djur har tagit fart. Så kallade von Ebnerlinjer uppstår dagligen i tänderna när nytt dentin deponeras och därefter mineraliseras. Genom att göra tvärsnitt genom en tand och räkna dessa tillväxtringar kan man således se hur många dagar tanden växt innan den ersattes av en ny s.k. ersättningstand. Denna metod har använts för att studera tänderna hos både människor och djur, men tandersättningen hos utdöda djur är ännu mycket outforskad, då endast ett fåtal studier (bl. a. av tänder från dinosaurier och däggdjursliknande reptiler) har genomförts. I denna studie har tillväxtlinjerna i tänder från mosasaurier (en grupp utdöda, havslevande varanödlor) och fossila krokodiler undersökts. Genom att jämföra de linjer som dessa djurs tänder uppvisar med linjer från djur med kända tandersättningscykler kan man styrka att tandersättningsmekanismen fungerat på samma sätt. Baserat på detta visar det sig att mosasaurier bytte sina tanduppsättningar under en tidsrymd som sträcker sig mellan 260 (cf. Platecarpus) och 593 dagar (Tylosaurus), medan de fossila krokodilerna bytte tänder något oftare; i snitt var 240:e dag. Trots variationen i ersättningscyklerna så har dentinet ackumulerats ungefär lika fort oberoende av djurens inbördes släktskap och tändernas storlek, vilket tyder på att tillväxthastigheten troligtvis styrts av genetiskt betingade faktorer och inte av levnadsförhållande eller födoval. Förutom von Ebnerlinjer observerades även så kallade Andresenlinjer i tänderna från cf. Platecarpus och Tylosaurus. Andresenlinjer har en annan depositionsrytm än von Ebnerlinjer, och är hitintills odokumenterade hos utdöda dju

Osteo-histology provides information on age, growth strategies, and lifestyles of both recent and ancient animals. This study deals with the histology of fossilized bone from three groups of tetrapods – sea turtles, ichthyosaurs and plesiosaurs – all secondarily adapted to marine life, but with rather different bone microstructures. As a result of extensive vascularization (i.e. osteoporosis), ichthyosaur bone is light, which may have contributed to increased manoeuvrability in open waters. This structure is comparable to that of most extant whales and dolphins. Plesiosaur bone, on the other hand, is very dense (i.e. pachyosteosclerotic) and therefore heavy. This extra weight may have been used for ballasting in a near-shore, shallow marine environment, indicative of habits similar to those of modern sirenians. Sea turtles display a lamellar, moderately vascularized bone pattern comparable to that of most recent turtles and crocodiles. This structure also indicates relatively slower growth rates compared to those of ichthyosaurs. The maturity of the animals at hand has also been investigated, and the sea turtle is adult, displaying at least 17 annual growth rings, whereas the ichthyosaur is a young adult or late juvenile and the plesiosaur is immature., Genom osteohistologiska analyser kan stora mängder information erhållas. Förutom möjligheten att uppskatta åldern och mognadsgraden hos ett djur kan tillväxtsmärken i skelettet, så kallade ’growth marks’ eller GM, också innehålla information om benens tillväxtshastighet, djurets tillväxtstrategi och till och med levnadssätt. Denna studie avhandlar histologin hos fossiliserade ben tillhörande en havssköldpadda, en fisködla och en svanödla, vilka alla var sekundärt anpassade till ett marint liv men hade skild skelettuppbyggnad. Fisködlebenet uppvisar en mycket stor kärlfrekvens (osteoporos) vilket kan ha minskat skelettets totala vikt och därmed förbättrat djurets rörelse- och manövreringsmöjligheter i öppna vatten. Denna benstruktur är jämförbar med den vi ser i de flesta av dagens valar och delfiner. Svanödlebenet är mycket kompakt (pachyosteosklerotiskt) vilket troligtvis bidragit till att skelettet var tungt. Denna extra vikt kan ha använts som ballast i en kustnära grundhavsmiljö, analogt med den livsstil dagens sirendjur har. Havssköldpaddan har en laminär, måttligt vaskulariserad benstruktur, jämförbar med nutida havssköldpaddor och krokodiler. Denna struktur påvisar också en långsam tillväxthastighet i förhållande till den hos fisködlan. Djurens ontogeni har också studerats och havssköldpaddebenet bedöms vara från ett vuxet djur, med en ålder av minst 17 år baserat på antalet tillväxtsringar, fisködlan var en äldre juvenil eller ett ungt vuxet djur, medan svanödlan var ett ungdjur.

Denna uppsats är tänkt att samla de fall där personer har gravlagts i romanska västtorn från tiden cirka 1050 – 1300 i det medeltida Danmark. Texten blir därmed en forskningsöversikt och en katalog rörande torngravar. Huvudfrågan med uppsatsen har varit att ta reda på om vem som helst fick bli begraven på detta sätt, om det är stiftargravar som vissa forskare påstår. Genom att väva in tolkningar av västtorn samt tolkningar om gravläggningar rent allmänt till de existerande torngravsteorierna, ges förhoppningsvis en bredare bild av fenomenet. Utifrån sammanställningen av torngravar och den tidigare forskningen anser författaren att stiftargravar är ett för snävt begrepp. Det kan mycket väl vara andra individer som blivit begravda i västtornen.