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  • 201.
    Ah-King, Malin
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Centre for Gender Research.
    Flexible mate choice2010In: Encyclopedia of Animal Behavior / [ed] Janice Moore & Michael D. Breed, Elsevier , 2010Chapter in book (Other academic)
  • 202.
    Ah-King, Malin
    Stockholm University, Faculty of Humanities, Department of Ethnology, History of Religions and Gender Studies, Gender Studies.
    Flexible Mate Choice2019In: Encyclopedia of Animal Behavior / [ed] Jae Chun Choe, Elsevier, 2019, 2, p. 421-431Chapter in book (Refereed)
    Abstract [en]

    Traditionally, investigators and theorists have supposed that mate choice is directional and fixed within a species as well as static within individuals over time. Lately, accumulating evidence shows that mate choice is often flexible, so that individuals change their behavior, depending on the social or ecological situation they experience or their condition. Recent theory proposes that animals should change their mate choice adaptively moment by moment in response to changes in environmental, internal, and social factors. Mate choice plasticity should be explored more in empirical studies as well as its implications for mate choice evolution and sexual selection.

  • 203.
    Ah-King, Malin
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Centre for Gender Research.
    Nature queer, vers un point de vue non-normatif sur la diversité biologique.2013In: Le sexe biologique - Anthologie historique et critique Volume 1, Femelles et Mâles ? Histoire naturelle des (deux) sexes / [ed] Thierry Hoquet, Editions Hermann, 2013Chapter in book (Refereed)
  • 204. Ah-King, Malin
    Phylogenetic analyses of parental care evolution2003Doctoral thesis, comprehensive summary (Other academic)
  • 205.
    Ah-King, Malin
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Centre for Gender Research.
    Queer nature: towards a non-normative perspective on biological diversity2009In: Body Claims, 2009Chapter in book (Other academic)
  • 206.
    Ah-King, Malin
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Centre for Gender Research.
    Queering animal sexual behavior in biology textbooks2013In: Confero: Essays on Education, Philosophy and Politics, ISSN 2001-4562, Vol. 1, no 2, p. 46-89Article in journal (Refereed)
  • 207.
    Ah-King, Malin
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Centre for Gender Research.
    Barron, Andrew B.
    Herberstein, Marie E.
    Genital Evolution: Why Are Females Still Understudied?2014In: PLoS biology, ISSN 1544-9173, E-ISSN 1545-7885, Vol. 12, no 5, p. e1001851-Article in journal (Refereed)
    Abstract [en]

    The diversity, variability, and apparent rapid evolution of animal genitalia are a vivid focus of research in evolutionary biology, and studies exploring genitalia have dramatically increased over the past decade. These studies, however, exhibit a strong male bias, which has worsened since 2000, despite the fact that this bias has been explicitly pointed out in the past. Early critics argued that previous investigators too often considered only males and their genitalia, while overlooking female genitalia or physiology. Our analysis of the literature shows that overall this male bias has worsened with time. The degree of bias is not consistent between subdisciplines: studies of the lock-and-key hypothesis have been the most male focused, while studies of cryptic female choice usually consider both sexes. The degree of bias also differed across taxonomic groups, but did not associate with the ease of study of male and female genital characteristics. We argue that the persisting male bias in this field cannot solely be explained by anatomical sex differences influencing accessibility. Rather the bias reflects enduring assumptions about the dominant role of males in sex, and invariant female genitalia. New research highlights how rapidly female genital traits can evolve, and how complex coevolutionary dynamics between males and females can shape genital structures. We argue that understanding genital evolution is hampered by an outdated single-sex bias.

  • 208. Ah-King, Malin
    et al.
    Elofsson, Helena
    Kvarnemo, Charlotta
    Rosenqvist, Gunilla
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Why is there no sperm competition in a pipefish with externally brooding males? Insights from sperm activitation and morphology2006In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 68, no 3, p. 958-962Article in journal (Refereed)
    Abstract [en]

    Nerophis ophidion sperm activation and morphology were investigated with the aim of explaining the apparent lack of sperm competition in this syngnathid with externally brooding males. Nerophis ophidion sperm were activated by a mixture of ovarian fluid and sea water, but not by sea water alone. This indicated that sperm were not shed into the water but needed to be released near the eggs, which probably restrained sperm competition.

  • 209.
    Ah-King, Malin
    et al.
    Stockholm University, Faculty of Humanities, Department of Ethnology, History of Religions and Gender Studies. Uppsala University, Sweden; University of California, USA.
    Gowaty, Patricia Adair
    A conceptual review of mate choice: stochastic demography, within-sex phenotypic plasticity, and individual flexibility2016In: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, no 14, p. 4607-4642Article, review/survey (Refereed)
    Abstract [en]

    Mate choice hypotheses usually focus on trait variation of chosen individuals. Recently, mate choice studies have increasingly attended to the environmental circumstances affecting variation in choosers' behavior and choosers' traits. We reviewed the literature on phenotypic plasticity in mate choice with the goal of exploring whether phenotypic plasticity can be interpreted as individual flexibility in the context of the switch point theorem, SPT (Gowaty and Hubbell ). We found >3000 studies; 198 were empirical studies of within-sex phenotypic plasticity, and sixteen showed no evidence of mate choice plasticity. Most studies reported changes from choosy to indiscriminate behavior of subjects. Investigators attributed changes to one or more causes including operational sex ratio, adult sex ratio, potential reproductive rate, predation risk, disease risk, chooser's mating experience, chooser's age, chooser's condition, or chooser's resources. The studies together indicate that choosiness of potential mates is environmentally and socially labile, that is, induced - not fixed - in the choosy sex with results consistent with choosers' intrinsic characteristics or their ecological circumstances mattering more to mate choice than the traits of potential mates. We show that plasticity-associated variables factor into the simpler SPT variables. We propose that it is time to complete the move from questions about within-sex plasticity in the choosy sex to between- and within-individual flexibility in reproductive decision-making of both sexes simultaneously. Currently, unanswered empirical questions are about the force of alternative constraints and opportunities as inducers of individual flexibility in reproductive decision-making, and the ecological, social, and developmental sources of similarities and differences between individuals. To make progress, we need studies (1) of simultaneous and symmetric attention to individual mate preferences and subsequent behavior in both sexes, (2) controlled for within-individual variation in choice behavior as demography changes, and which (3) report effects on fitness from movement of individual's switch points.

  • 210.
    Ah-King, Malin
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Centre for Gender Research. Dept Ecol & Evolutionary Biol, 621 Charles E Young Dr S, Los Angeles, CA 90095 USA.;Stockholm Univ, Dept Ethnol Hist Relig & Gender Studies, Univ Vagen 10 E, SE-10691 Stockholm, Sweden..
    Gowaty, Patricia Adair
    Dept Ecol & Evolutionary Biol, 621 Charles E Young Dr S, Los Angeles, CA 90095 USA.;Smithsonian Trop Res Inst, DPO, Box 0948,AA 34002-9998, Washington, DC USA.;Univ Calif Los Angeles, Inst Environm & Sustainabil, Los Angeles, CA 90095 USA..
    A conceptual review of mate choice: stochastic demography, within-sex phenotypic plasticity, and individual flexibility2016In: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, no 14, p. 4607-4642Article, review/survey (Refereed)
    Abstract [en]

    Mate choice hypotheses usually focus on trait variation of chosen individuals. Recently, mate choice studies have increasingly attended to the environmental circumstances affecting variation in choosers' behavior and choosers' traits. We reviewed the literature on phenotypic plasticity in mate choice with the goal of exploring whether phenotypic plasticity can be interpreted as individual flexibility in the context of the switch point theorem, SPT (Gowaty and Hubbell ). We found >3000 studies; 198 were empirical studies of within-sex phenotypic plasticity, and sixteen showed no evidence of mate choice plasticity. Most studies reported changes from choosy to indiscriminate behavior of subjects. Investigators attributed changes to one or more causes including operational sex ratio, adult sex ratio, potential reproductive rate, predation risk, disease risk, chooser's mating experience, chooser's age, chooser's condition, or chooser's resources. The studies together indicate that choosiness of potential mates is environmentally and socially labile, that is, induced - not fixed - in the choosy sex with results consistent with choosers' intrinsic characteristics or their ecological circumstances mattering more to mate choice than the traits of potential mates. We show that plasticity-associated variables factor into the simpler SPT variables. We propose that it is time to complete the move from questions about within-sex plasticity in the choosy sex to between- and within-individual flexibility in reproductive decision-making of both sexes simultaneously. Currently, unanswered empirical questions are about the force of alternative constraints and opportunities as inducers of individual flexibility in reproductive decision-making, and the ecological, social, and developmental sources of similarities and differences between individuals. To make progress, we need studies (1) of simultaneous and symmetric attention to individual mate preferences and subsequent behavior in both sexes, (2) controlled for within-individual variation in choice behavior as demography changes, and which (3) report effects on fitness from movement of individual's switch points.

  • 211.
    Ah-King, Malin
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Centre for Gender Research.
    Hayward, Eva
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Centre for Gender Research.
    Toxic sexes—Perverting pollution and queering hormone disruption2013In: O-zone: A Journal of Object Oriented Studies, ISSN ISSN 2326-8344, Vol. 1Article in journal (Refereed)
  • 212.
    Ah-King, Malin
    et al.
    Zoologiska institutionen, Stockholms universitet.
    Kvarnemo, Charlotta
    Zoologiska institutionen, Stockholms universitet.
    Tullberg, Birgitta S.
    Zoologiska institutionen, Stockholms universitet.
    The influence of territoriality and mating system for the evolution of male care, a phylogenetic study on fish2005In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101Article in journal (Refereed)
    Abstract [en]

    Evolution of male care is still poorly understood. Using phylogeneticallymatched-pairs comparisons we tested for effects of territoriality and matingsystem on male care evolution in fish. All origins of male care were found inpair-spawning species (with or without additional males such as sneakers) andnone were found in group-spawning species. However, excluding groupspawners, male care originated equally often in pair-spawning species withadditional males as in strict pair-spawning species. Evolution of male care wasalso significantly related to territoriality. Yet, most pair-spawning taxa withmale care are also territorial, making their relative influence difficult toseparate. Furthermore, territoriality also occurs in group-spawning species.Hence, territoriality is not sufficient for male care to evolve. Rather, we arguethat it is the combination of territoriality and pair spawning with sequentialpolygyny that favours the evolution of male care, and we discuss our results inrelation to paternity assurance and sexual selection.

  • 213. Ah-King, Malin
    et al.
    Nylin, Sören
    Stockholm University, Faculty of Science, Department of Zoology.
    Sex in an Evolutionary Perspective: Just Another Reaction Norm2010In: Evolutionary biology, ISSN 0071-3260, E-ISSN 1934-2845, Vol. 37, no 4, p. 234-246Article, review/survey (Refereed)
    Abstract [en]

    It is common to refer to all sorts of clear-cut differences between the sexes as something that is biologically almost inevitable. Although this does not reflect the status of evolutionary theory on sex determination and sexual dimorphism, it is probably a common view among evolutionary biologists as well, because of the impact of sexual selection theory. To get away from thinking about biological sex and traits associated with a particular sex as something static, it should be recognized that in an evolutionary perspective sex can be viewed as a reaction norm, with sex attributes being phenotypically plastic. Sex determination itself is fundamentally plastic, even when it is termed "genetic". The phenotypic expression of traits that are statistically associated with a particular sex always has a plastic component. This plasticity allows for much more variation in the expression of traits according to sex and more overlap between the sexes than is typically acknowledged. Here we review the variation and frequency of evolutionary changes in sex, sex determination and sex roles and conclude that sex in an evolutionary time-frame is extremely variable. We draw on recent findings in sex determination mechanisms, empirical findings of morphology and behaviour as well as genetic and developmental models to explore the concept of sex as a reaction norm. From this point of view, sexual differences are not expected to generally fall into neat, discrete, pre-determined classes. It is important to acknowledge this variability in order to increase objectivity in evolutionary research.

  • 214.
    Ah-King, Malin
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Centre for Gender Research.
    Nylin, Sören
    Zoologiska institutionen, Stockholms universitet.
    Sex in an Evolutionary Perspective: Just Another Reaction Norm2010In: Evolutionary biology, ISSN 0071-3260, E-ISSN 1934-2845, Vol. 37, no 4, p. 234-246Article, review/survey (Refereed)
    Abstract [en]

    It is common to refer to all sorts of clear-cut differences between the sexes as something that is biologically almost inevitable. Although this does not reflect the status of evolutionary theory on sex determination and sexual dimorphism, it is probably a common view among evolutionary biologists as well, because of the impact of sexual selection theory. To get away from thinking about biological sex and traits associated with a particular sex as something static, it should be recognized that in an evolutionary perspective sex can be viewed as a reaction norm, with sex attributes being phenotypically plastic. Sex determination itself is fundamentally plastic, even when it is termed “genetic”. The phenotypic expression of traits that are statistically associated with a particular sex always has a plastic component. This plasticity allows for much more variation in the expression of traits according to sex and more overlap between the sexes than is typically acknowledged. Here we review the variation and frequency of evolutionary changes in sex, sex determination and sex roles and conclude that sex in an evolutionary time-frame is extremely variable. We draw on recent findings in sex determination mechanisms, empirical findings of morphology and behaviour as well as genetic and developmental models to explore the concept of sex as a reaction norm. From this point of view, sexual differences are not expected to generally fall into neat, discrete, pre-determined classes. It is important to acknowledge this variability in order to increase objectivity in evolutionary research.

  • 215.
    Ah-King, Malin
    et al.
    Zoologiska institutionen, Stockholms universitet.
    Tullberg, Birgitta S.
    Zoologiska institutionen, Stockholms universitet.
    Phylogenetic analysis of twinning in Callitrichinae2000In: American Journal of Primatology, ISSN 0275-2565, E-ISSN 1098-2345, Vol. 51, no 2, p. 135-146Article in journal (Refereed)
    Abstract [en]

    The callitrichines are known for twinning and for a communal rearingsystem in which all or most group members help care for the offspring.The origin of twinning has been the subject of much speculation. In thisstudy predictions from earlier hypotheses are tested on the basis of twoalternative phylogenetic trees. From this analysis we infer that helpingbehavior and male care preceded the origin of twinning, and that thesetraits did not coevolve with, but might have been important prerequisitesfor twinning in callitrichines. Small body size does not necessarilyresult in twinning, although it might still have been a prerequisite forits evolution. Gum feeding was an ecological change which evolved alongwith twinning. If nutrition was a limiting factor in the number of offspringproduced, then the use of a new feeding resource could have beencrucial for the origin of twinning in callitrichines. According to one of thetwo alternative solutions inferred by the total evidence tree, and in accordancewith the morphological tree, semi-annual breeding appears inthe marmosets together with specialization in gum feeding. The fact thatgums are available for these monkeys all year may have facilitated semiannualbreeding. We suggest that the exploitation of gums as a feedingresource could have been the decisive factor in the increase of the reproductiverate by twinning and by semi-annual breeding.

  • 216.
    Ahl, David
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology, Integrative Physiology.
    Roos, Stefan
    Phillipson, Mia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology, Integrative Physiology.
    Holm, Lena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology, Integrative Physiology.
    CX3CR1 deficiency alters response to L-reuteri treatment of DSS-induced colitis in mice2014In: The FASEB Journal, ISSN 0892-6638, E-ISSN 1530-6860, Vol. 28, no 1, article id 902.10Article in journal (Other academic)
  • 217. Ahlandsberg, Staffan
    Metabolic engineering of starch synthesis in barley2001Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Starch is an important industrial raw material both for food and non-food purposes. In plants, starch is deposited in the leaf and in the storage tissues such as seed endosperm, roots or tubers. Starch is a glucose polymer, and its synthesis involves four groups of enzymes, ADP-glucose-pyrophosphorylase (AGPase), starch synthases (SS), starch branching enzymes (SBE), and starch debranching enzymes (DBE). In barley, four isoforms of SBE have been identified and the temporal and spatial expression of their genes (sbe) has been studied in our lab.

    The long-term objective of our research is to produce novel starches in planta for industrial applications. This requires the transformation of barley in order to produce transgenic plants with altered activity for one or more sbe genes. Using a plant-optimized version of Green Fluorescent Protein (GFP) as the only marker we produced a transgenic Nordic elite cultivar of barley in 1999. The usefulness of GFP as a marker has also been applied in various transient experiments and for this reason a set of monocotyledonous expression vectors has been developed. Using these vectors, the spatial expression pattern of the sbeII genes has been investigated.

    The sbeIIa and sbeIIb genes are differentially transcribed during barley seed development. The sbeIIb gene is expressed exclusively in the endosperm while the sbeIIa gene is expressed also in embryonic and vegetative tissues. The tissue specific regulation of the sbeII genes was hown to be executed via a repressor protein acting on a cis element located in the second intron of the sbeIIb gene. We also suggest that the repression is controlled by the local sugar concentration in the barley seed endosperm.

  • 218.
    Ahlbeck, Ida
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Living in a predation matrix: Studies on fish and their prey in a Baltic Sea coastal area2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis was written within the framework of a biomanipulation project where young-of-the-year (YOY) pikeperch (Sander lucioperca) were stocked to a Baltic Sea bay to improve water quality through a top-down trophic cascade. The aim of my doctorial studies was however focused on a broader ecological question, namely predation (the main driving force in a biomanipulation). Hence, this thesis consists of four papers where we study the interactions between predator and prey using fish and zooplankton and how these interactions can be measured.

    In paper I we evaluated the performance of different diet analysis methods by individual based modelling and found that when having a nutritional gain perspective, mass based methods described diets best. Paper II investigated how the explorative, foraging and anti-predator behaviour of the YOY pikeperch used for stocking were affected by their rearing environment (pond vs. tank rearing). The more complex and varied environment in the semi-natural ponds seemed to promote a more flexible and active behaviour, better equipping young fish for survival in the wild. For paper III we studied the diel vertical migration in the six copepodite stages of the zooplankton Acartia spp. and Eurytemora affinis in relation to fish biomass, phytoplankton abundance and temperature. Both species migrated and in addition showed increased migration range with size within species, indicating evasion from visual predators. Paper IV addressed the movement of littoral Eurasian perch (Perca fluviatilis) via stable isotope signatures (13C and 15N) and body condition. We found clear indications of sedentarity and intra-habitat dietary differences. Interactions between predators and prey are complex and affected by both physiological and environmental characteristics as well as behavioural traits. The results in this thesis suggest that different species and even different life stages pursue different strategies to survive.

  • 219.
    Ahlbeck, Ida
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Hansson, Sture
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Hjerne, Olle
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Evaluating fish diet analysis methods by individual-based modelling2012In: Canadian Journal of Fisheries and Aquatic Sciences, ISSN 0706-652X, E-ISSN 1205-7533, Vol. 69, no 7, p. 1184-1201Article in journal (Refereed)
    Abstract [en]

    Knowledge of diet compositions is important in ecological research. There are many methods available and numerous aspects of diet composition. Here we used modelling to evaluate how well different diet analysis methods describe the true diet of fish, expressed in mass percentages. The methods studied were both basic methods (frequency of occurrence, dominance, numeric, mass, points) and composite indices (Index of Relative Importance, Comparative Feeding Index). Analyses were based on both averaged stomach content of individual fish and on pooled content from several fish. Prey preference, prey size, and evacuation rate influenced the performance of the diet analysis methods. The basic methods performed better than composite indices. Mass and points methods produced diet compositions most similar to the true diet and were also most robust, indicating that these methods should be used to describe energetic-nutritional sources of fish.

  • 220.
    Ahlbeck, Ida
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Hansson, Sture
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Hjerne, Olle
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Evaluation of diet analysis methods by individual based modellingIn: Canadian Journal of Fisheries and Aquatic Sciences, ISSN 0706-652X, E-ISSN 1205-7533Article in journal (Refereed)
  • 221.
    Ahlbeck, Ida
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Hansson, Sture
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Karlöf, Oliver
    Sedentarity in Eurasian perch (Perca fluviatilis) in a coastal Baltic Sea areaIn: Ecology of Freshwater Fish, ISSN 0906-6691, E-ISSN 1600-0633Article in journal (Refereed)
  • 222.
    Ahlbeck, Ida
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Holliland, Per B.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Rearing environment affect important life skills in pikeperch (Sander lucioperca)2012In: Boreal environment research, ISSN 1239-6095, E-ISSN 1797-2469, Vol. 17, no 3-4, p. 291-304Article in journal (Refereed)
    Abstract [en]

    The effect of rearing environment on the behaviour of young-of-the-year pikeperch (Sander lucioperca) bred at three different production facilities was investigated. Two groups were reared in semi-natural ponds and one group in indoor tanks. Exploratory, foraging and anti-predator behaviours were studied in aquarium experiments. There were no significant differences between pond- and tank-reared fish in reluctance to explore their new environment, but pond-reared fish spent significantly more time in macro-vegetation. Pond-reared fish were significantly faster to start foraging on live prey (Neomysis integer) that they had not encountered before. As compared with tank-reared fish, pond-reared fish were also significantly more active in their anti-predator response. Rearing environment obviously influences the development of important life skills. These differences may impact the success rate when stocking young-of-the-year pikeperch into natural waters.

  • 223.
    Ahlberg, Per
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Can fossils illuminate the evolution of gnathostome head development?2006In: European Society for Evolutionary Developmental Biology: The First and Founding Meeting, August 2006, Prague, 2006, p. 363-Conference paper (Other (popular scientific, debate etc.))
  • 224.
    Ahlberg, Per
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology. Evolutionär organismbiologi.
    CT scanning the nose of Eusthenopteron.2006In: Journal of Vertebrate Paleontology, ISSN 0272-4634, Vol. 26, no 3(supplement), p. 35A-Article in journal (Other scientific)
  • 225.
    Ahlberg, Per
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology. Evolutionär organismbiologi.
    Fossils, developmental patterning and the origin of tetrapods.2003In: The new panorama of animal evolution, Pensoft Publishers, Sofia, Bulgaria , 2003, p. 45-54Chapter in book (Refereed)
  • 226.
    Ahlberg, Per
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology. Evolutionär organismbiologi.
    Clack, Jennifer
    Blom, Henning
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    The axial skeleton of the Devonian tetrapod Ichthyostega.2005In: Nature, ISSN 0028-0836, Vol. 437, no 7055, p. 137-140Article in journal (Refereed)
    Abstract [en]

    Ichthyostega was the first Devonian tetrapod to be subject to a whole-body reconstruction and remains, together with Acanthostega one of only two Devonian tetrapods for which near-complete postcranial material is available. It is thus crucially important for our understanding of the earliest stages of tetrapod evolution and terrestrialization. Based on extensive re-examination of original material, augmented by recently collected specimens, we present a new reconstruction of Ichthyostega that differs substantially from those previously published and reveals hitherto unrecognised regionalization in the vertebral column. Ichthyostega is the earliest vertebrate to show obvious adaptations for non-swimming locomotion. Uniquely among early tetrapods, the presacral vertebral column shows pronounced regionalization of neural arch morphology, suggesting that it was adapted for dorsoventral rather than lateral flexion.

  • 227.
    Ahlberg, Per
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Clack, Jennifer
    Luksevics, Ervins
    Blom, Henning
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Zupins, Ivars
    Ventastega curonica and the origin of tetrapod morphology2008In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 453, no 7199, p. 1199-1204Article in journal (Refereed)
    Abstract [en]

    The gap in our understanding of the evolutionary transition from fish to tetrapod is beginning to close thanks to the discovery of new intermediate forms such as Tiktaalik roseae. Here we narrow it further by presenting the skull, exceptionally preserved braincase, shoulder girdle and partial pelvis of Ventastega curonica from the Late Devonian of Latvia, a transitional intermediate form between the 'elpistostegids' Panderichthys and Tiktaalik and the Devonian tetrapods (limbed vertebrates) Acanthostega and Ichthyostega. Ventastega is the most primitive Devonian tetrapod represented by extensive remains, and casts light on a part of the phylogeny otherwise only represented by fragmentary taxa: it illuminates the origin of principal tetrapod structures and the extent of morphological diversity among the transitional forms

  • 228.
    Ahlberg, Per E.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Birth of the jawed vertebrates2009In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 457, p. 1094-1095Article in journal (Other academic)
    Abstract [en]

    The discovery of embryos in certain fossil fishes not only shows that internal fertilization and live birth evolved early in vertebrate history, but also raises questions about the origin of jawed vertebrates.

  • 229.
    Ahlberg, Per E.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Eusthenopteron foordi, Fossil Lobe-finned Fish. In Digital Morphology (DigiMorph)2007Other (Other (popular science, discussion, etc.))
  • 230.
    Ahlberg, Per E.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Fossils, developmental patterning and the origin of tetrapods2003In: The new panorama of animal evolution: Proceedings of the 18th international congress of zoology, Sofia and Moscow: Pensoft Publishers , 2003, p. 44-54Chapter in book (Other academic)
  • 231.
    Ahlberg, Per E
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology. Evolutionär organismbiologi.
    The early evolution of the tetrapod humerus2004In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 305, no 5691, p. 1715-1715Article in journal (Other academic)
  • 232.
    Ahlberg, Per E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Blom, HenningUppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.Boisvert, CatherineUppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Forty years of Early Vertebrates: papers from the 11th International Symposium on Early and Lower Vertebrates2009Collection (editor) (Other academic)
  • 233.
    Ahlberg, Per E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Blom, Henning
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Boisvert, Catherine
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Introduction: Forty years of Early Vertebrates: papers from the 11th International Symposium on Early and Lower Vertebrates.2009In: Forty years of Early Vertebrates: papers from the 11th International Symposium on Early and Lower Vertebrates., 2009, p. 1-2Conference paper (Refereed)
  • 234.
    Ahlberg, Per E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Blom, Henning
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Brazeau, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Clément, Gaël
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Snitting, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    The virtual Eusthenopteron: inside the head of a Devonian lobe-fin with CT. In A. Ivanov and G. Young (eds.), Middle Palaeozoic Vertebrates from Laurussia: Relationships with Siberia, Kazakhstan, Asia and Gondwana. Ichthyolith Issues Special Publication 9:3–4.2005Other (Other academic)
  • 235.
    Ahlberg, Per E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Clack, Jennifer A.
    Palaeontology: A firm step from water to land2006In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 440, no 7085, p. 747-749Article in journal (Refereed)
  • 236.
    Ahlberg, Per Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Humeral homology and the origin of the tetrapod elbow: a reinterpretation of the enigmatic specimens ANSP 21350 and GSM 1045362011In: Studies on fossil tetrapods / [ed] P. M. Barrett, A. R. Milner, London: The Palaeontological Association , 2011, p. 17-29Chapter in book (Refereed)
    Abstract [en]

    Two putative tetrapod humeri of Devonian age, ANSP 21350 from the late Famennian of Pennsylvania and GSM 104536 from the late Frasnian of Scat Craig, Scotland, are reinterpreted in the light of more recent discoveries. The morphology of ANSP 21350 can be more fully homologized with those of elpistostegids and early tetrapods than previously recognized. Unique features include distally displaced dorsal muscle attachments and a ventrally rotated distal face of the bone. This suggests that a weight-bearing ventrally directed forearm was created, not by means of a flexed elbow as in other tetrapods, but by distorting the humerus. The olecranon process on the ulna was probably poorly developed or absent. Primitive characters that are absent in other tetrapods add support to the contention that ANSP 21350 is the least crownward of known tetrapod humeri. Contrary to previous claims, Acanthostega has a characteristic tetrapod ulnar morphology with an olecranon process; it does not resemble an elpistostegid ulna and is not uniquely primitive for tetrapods. This suggests that the flexed tetrapod elbow with ulnar extensor muscles attached to the olecranon evolved simultaneously with the large rectangular entepicondyle typical for early tetrapods, probably as part of a single functional complex. GSM 104536 is denfinitely not a primitive tetrapod humerus, nor a sarcopterygian branchial bone, but cannot be positively identified at present.    

  • 237.
    Ahlberg, Per Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Sky konspiratörernas dimma - I: Uppsala Nya Tidning (UNT), 27 dec2008Other (Other (popular science, discussion, etc.))
  • 238.
    Ahlberg, Per Erik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Trinajstic, Kate
    Johanson, Zerina
    Long, John
    Pelvic claspers confirm chondrichthyan-like internal fertilization in arthrodires2009In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 460, no 7257, p. 888-889Article in journal (Refereed)
    Abstract [en]

    Recent finds(1,2) demonstrate that internal fertilization and   viviparity (live birth) were more widespread in the Placodermi, an   extinct group of armoured fishes, than was previously realized.   Placoderms represent the sister group of the crown group jawed   vertebrates (Gnathostomata)(3,4), making their mode(s) of reproduction   potentially informative about primitive gnathostome conditions. An   ossified pelvic fin basipterygium discovered in the arthrodire   Incisoscutum ritchiei was hypothesized to be identical in males and   females, with males presumed to have an additional cartilaginous   element or series forming a clasper. Here we report the discovery of a   completely ossified pelvic clasper in Incisoscutum ritchiei (WAM   03.3.28) which shows that this interpretation was incorrect: the   basipterygium described previously(1) is in fact unique to females. The   male clasper is a slender rod attached to a square basal plate that   articulates directly with the pelvis. It carries a small cap of dermal   bone covered in denticles and small hooks that may be homologous with   the much larger dermal component of the ptyctodont clasper.

  • 239.
    Ahlberg, Per
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology. Evolutionär organismbiologi.
    Friedman, Matt
    Blom, Henning
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    New light on the earliest known tetrapod jaw.2005In: Journal of Vertebrate Paleontology, ISSN 0272-4634, Vol. 25, no 3, p. 720-724Article in journal (Refereed)
  • 240.
    Ahlberg, Per
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology. Evolutionär organismbiologi.
    Köntges, Georgy
    Homologies and cell populations: a response to Sánchez-Villagra and Maier.2006In: Evolution and Development, ISSN 1520-541X, Vol. 8, p. 116-118Article in journal (Other (popular scientific, debate etc.))
  • 241.
    Ahlberg, Per
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Smith, Moya
    MRC Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK.
    Johanson, Zerina
    Department of Biological Sciences and MUCEP, Department of Earth and Planetary Sciences, Macquarie University, Sydney 2010, Australia.
    Developmental plasticity and disparity in early dipnoan (lungfish) dentitions.2006In: Evolution & Development, ISSN 1520-541X, E-ISSN 1525-142X, Vol. 8, no 4, p. 331-349Article in journal (Refereed)
    Abstract [en]

    Although the lungfish (Dipnoi) belong within the Osteichthyes, their dentitions are radically different from other osteichthyans. Lungfish dentitions also show a uniquely high structural disparity during the early evolution of the group, partly owing to the independent variation of odontogenic and odontoclastic processes that are tightly and stereotypically coordinated in other osteichthyans. We present a phylogenetic analysis of early lungfishes incorporating a novel approach to coding these process characters in preference to the resultant adult dental morphology. The results only partially resolve the interrelationships of Devonian dipnoans, but show that the widely discussed hypothesis of separate tooth-plated, dentine-plated, and denticulated lineages is unlikely to be true. The dipnoan status of Diabolepis is corroborated. Lungfish dentitions seem to have undergone extensive and nonparsimonious evolution during the early history of the group, but much of the resulting disparity can be explained by a modest number of evolutionary steps in the underlying developmental processes, those for dental formation (odontogenic) and those for the remodeling of dentine tissue (odontoclastic). Later in lungfish evolution, this disparity was lost as the group settled to a pattern of dental development that is just as stereotypic as, but completely different from, that of other osteichthyans.

  • 242.
    Ahlbert, Inga-Britt
    Stockholm University.
    Organization of the cone cells in the retinae of some teleosts in relation to their feeding habits1975Doctoral thesis, comprehensive summary (Other academic)
  • 243.
    Ahlborg, Niklas
    Stockholm University, Faculty of Science, The Wenner-Gren Institute, Immunology.
    Immune responses to repeat sequences of the Plasmodium falciparum malaria antigen Pf3321995Doctoral thesis, comprehensive summary (Other academic)
  • 244.
    Ahlen, Ingemar
    Executive, Universitet, Swedish University of Agricultural Sciences, Sveriges lantbruksuniversitet, skoglig resurshållning.
    Skydd av biotoper för bevarande av vitryggig hackspett i nedre Dalälven1976Report (Other academic)
    Abstract [sv]

    Den vitryggiga hackspetten Dendrocopos leucotos, som ursprungligen förekommit över nästan hela landet, har under de senaste hundra åren blivit allt sällsyntare och finns nu, förutom i några spridda förekomster av enstaka par eller ensamma fåglar, i landet endast kvar med en fast population i nedre Dalälvsområdet mellan Avesta och Älvkarleby.

    De hotade hackspettarterna har sedan 1974 varit föremål för ekologisk forskning och inventeringsarbete. I bilagda ”information om projekt hackspettars ekologi” 1976-01-18 redovisas projektets syfte och kortfattad redogörelse för arbetet under 1975 ges. Hänvisning kan också göras till tidskriften Vår Fågelvärlds första nummer 1976 där resultat av 1973 års riksinventering av gråspett och vitryggig hackspett redovisas.

  • 245.
    Ahlgren Berg, Alexandra
    Stockholm University, Faculty of Science, Department of Genetics, Microbiology and Toxicology.
    Developmental switches in a family of temperate phages2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    P2 is the prototype phage of the non-lambdoid P2 family of temperate phages. A developmental switch determines whether a temperate phage will grow lytically or form lysogeny after infection. P2 related phages have two face-to-face located promoters controlling the lysogenic and the lytic operon respectively, and two repressors. The immunity C repressor of P2 is the first gene of the lysogenic operon and it represses the lytic promoter. The Cox protein, the first gene of the lytic operon, is multifunctional. It represses the lysogenic promoter, acts as a directionality factor in site-specific recombination and activates the PLL promoter of satellite phage P4.

    This thesis focuses on comparisons between the developmental switches of P2 and the two heteroimmune family members, P2 Hy dis and WΦ. A characterization of the developmental switch region of P2 Hy dis identifies a directly repeated sequence which is important for C repression. P2 Hy dis Cox can substitute for P2 Cox in repression of the P2 lysogenic promoter, excision of a P2 prophage and activation of P4 PLL. The P4 ε protein can derepress the developmental switch of P2 Hy dis.

    Functional characterizations of the C repressors and Cox proteins of P2 and WΦ show that both C repressors induce bending of their respective DNA targets. WΦ C, like P2 C, has a strong dimerization activity in vivo, but there are no indications of higher oligomeric forms. Despite the high degree of identity in the C-terminus, required for dimerization in P2 C, they seem to be unable to form heterodimers. The two Cox proteins are predicted to have identical secondary structures containing a helix-turn-helix motif believed to be involved in DNA binding. It is, however, not possible to change the DNA specificity of P2 Cox to that of WΦ Cox by swapping the presumed recognition helix. P2 Cox recognizes a sequence repeated at least six times in the different targets, while WΦ Cox seems to recognize a single direct repeat. In contrast to P2 Cox, WΦ Cox binds with a stronger affinity to the switch region than to the attachment site (attP). The Cox proteins induce a strong bend in their DNA targets, strengthening the hypothesis that they have a structural role at site-specific recombination. Both proteins show a capacity to oligomerize, but P2 Cox has a higher tendency to form oligomers than WΦ Cox.

    The P2 integrase mediates site-specific recombination leading to integration or excision of the P2 genome in or out of the host chromosome. P2 Cox controls the direction by inhibiting integration and promoting excision. In this work it is shown that Cox and Int bind cooperatively to attP.

  • 246.
    Ahlgren, Gunnel
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Limnology. Limnologi.
    Hyenstrand, Per
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Limnology. Limnologi.
    Nitrogen limitation effects of different nitrogen sources on nutritional quality of two freshwater organisms, Scenedesmus Quadricauda (Clorophyceae) and Synechococcus sp. (Cyanophyceae)2003In: J. Phycol., Vol. 39, p. 906-917Article in journal (Refereed)
  • 247.
    Ahlgren, Gunnel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Limnology.
    Tilahun, Girma
    Fatty acid quality of the basic food web in the Ethiopian lakes Awassa, Chamo, and Ziway2008In: INTERNATIONAL ASSOCIATION OF THEORETICAL AND APPLIED LIMNOLOGY, VOL 30, PT 4, PROCEEDINGS / [ed] Jones J, Faaborg J, 2008, Vol. 30, no 4, p. 581-586Conference paper (Refereed)
  • 248.
    Ahlgren, Gunnel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Limnology.
    Vrede, Tobias
    Goedkoop, Willem
    Fatty acid ratios in freshwater fish, zooplankton and zoobenthos - Are there specific optima?2009In: Lipids in aquatic ecosystems / [ed] Michael T. Arts, Michael T. Brett, Martin J. Kainz, London: Springer , 2009, p. 147-178Chapter in book (Other (popular science, discussion, etc.))
  • 249.
    Ahlgren, Gunnel
    et al.
    Department of Ecology and Evolution (Limnology), Uppsala University, Uppsala, Sweden.
    Vrede, Tobias
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Goedkoop, Willem
    Department of Environmental Assessment, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden.
    Fatty Acid Ratios in Freshwater Fish, Zooplankton and Zoobenthos - Are There Specific Optima?2009In: Lipids in Aquatic Ecosystems / [ed] Martin Kainz, Michael T. Brett, Michael T. Arts, New York: Springer-Verlag New York, 2009, p. 147-178Chapter in book (Other academic)
    Abstract [en]

    Two groups of polyunsaturated fatty acids (PUFA), termed omega-3 and omega-6 in food (or here as n-3 and n-6 PUFA, respectively), are essential for all vertebrates and probably also for nearly all invertebrates. The absolute concentrations of the different PUFA are important, as is an appropriate balance between the two. The optimal ratio of n-3/n-6 is not known for most organisms but is anticipated to be more or less species-specific (Sargent et al. 1995). The three most important PUFA in vertebrates are eicosapentaenoic acid (EPA, 20:5n-3), docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (ARA, 20:4n-6). Both EPA and ARA are precursors for biologically active eicosanoids that are vital components of cell membranes and play many dynamic roles in mediating and controlling a wide array of cellular activities (Crawford et al. 1989; Harrison 1990; Henderson et al. 1996; see Chap. 9). Since n-3 and n-6 PUFA cannot be synthesized de novo by most metazoans, they must be included in the diet, either as EPA, DHA and ARA, or as their precursors, such as α-linolenic acid (ALA, 18:3n-3, precursor of EPA and DHA) and linoleic acid (LIN, 18:2n-6, precursor of ARA) (Bell et al. 1986; Sargent et al. 1995). Both ALA and LIN are produced in the thylacoid membranes of algae and plants with chlorophyll (Sargent at al. 1987).

  • 250.
    Ahlgren, Hans
    et al.
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies.
    Norén, Karin
    Stockholm University, Faculty of Science, Department of Zoology.
    Angerbjörn, Anders
    Stockholm University, Faculty of Science, Department of Zoology.
    Lidén, Kerstin
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies.
    Multiple prehistoric introductions of the mountain hare (Lepus timidus) on a remote island, as revealed by ancient DNA2016In: Journal of Biogeography, ISSN 0305-0270, E-ISSN 1365-2699, Vol. 43, no 9, p. 1786-1796Article in journal (Refereed)
    Abstract [en]

    Aim: The majority of the non-volant mammals now present on the island of Gotland, Sweden, have been introduced in modern times. One exception is the mountain hare (Lepus timidus), which was present on the island more than 9000 years ago. This paper investigates the origins of the Gotland hares and temporal changes in their genetic structure, and considers how they may have reached the island.

    Location: The island of Gotland, Sweden (57°30′ N, 18°20′ E).

    Methods: Two fragments of the mitochondrial D-loop 130 + 164 base pairs in length from skeletal remains from 40 ancient mountain hares from Gotland, 38 from the Swedish mainland and five from Lithuania were analysed and compared with 90 modern L. timidus haplotypes from different locations in Eurasia and five haplotypes of the Don-hare (Lepus tanaiticus) morphotype.

    Results: The Mesolithic hares from Gotland (7304 bc–5989 bc) cluster with modern hares from Russia, Scotland, the Alps and Fennoscandia whereas the Gotland hares from the Neolithic and onwards (2848 bc–1641 ad) cluster with Neolithic hares from the Swedish mainland and modern hares from Fennoscandia. The Neolithic haplotypes from Lithuania and the Don-hare haplotypes were dispersed within the network. The level of differentiation (FST) between the Mesolithic and Neolithic hares on Gotland was twice as great as that observed on the mainland.

    Main conclusions: The ancient hares on Gotland fall into two haplogroups separated in time, indicating that the mountain hare became extinct at one point, with subsequent re-colonization events. In view of the isolated location of Gotland, it is probable that the hares were brought there by human means of transport.

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