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  • 1. Anderies, J. M.
    et al.
    Folke, Carl
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. Royal Swedish Academy of Sciences, Sweden.
    Connecting human behaviour, meaning and nature2024Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 379, nr 1903, artikel-id 20220314Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Much of the discourse around climate change and the situation of diverse human societies and cultures in the Anthropocene focuses on responding to scientific understanding of the dynamics of the biosphere by adjusting existing institutional and organizational structures. Our emerging scientific understanding of human behaviour and the mechanisms that enable groups to achieve large-scale coordination and cooperation suggests that incrementally adjusting existing institutions and organizations will not be sufficient to confront current global-scale challenges. Specifically, the transaction costs of operating institutions to induce selfish rational actors to consider social welfare in their decision-making are too high. Rather, we highlight the importance of networks of shared stories that become real—imagined orders—that create context, meaning and shared purpose for framing decisions and guiding action. We explore imagined orders that have contributed to bringing global societies to where they are and propose elements of a science-informed imagined order essential to enabling societies to flourish in the Anthropocene biosphere.

  • 2. Beaugrand, G.
    et al.
    Conversi, A.
    Chiba, S.
    Edwards, M.
    Fonda-Umani, S.
    Greene, C.
    Mantua, N.
    Otto, Saskia A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. University of Hamburg, Germany.
    Reid, P. C.
    Stachura, M. M.
    Stemmann, L.
    Sugisaki, H.
    Synchronous marine pelagic regime shifts in the Northern Hemisphere2015Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, nr 1659, artikel-id 20130272Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Regime shifts are characterized by sudden, substantial and temporally persistent changes in the state of an ecosystem. They involve major biological modifications and often have important implications for exploited living resources. In this study, we examine whether regime shifts observed in 11 marine systems from two oceans and three regional seas in the Northern Hemisphere (NH) are synchronous, applying the same methodology to all. We primarily infer marine pelagic regime shifts from abrupt shifts in zooplankton assemblages, with the exception of the East Pacific where ecosystem changes are inferred from fish. Our analyses provide evidence for quasi-synchronicity of marine pelagic regime shifts both within and between ocean basins, although these shifts lie embedded within considerable regional variability at both year-to-year and lower-frequency time scales. In particular, a regime shift was detected in the late 1980s in many studied marine regions, although the exact year of the observed shift varied somewhat from one basin to another. Another regime shift was also identified in the mid-to late 1970s but concerned less marine regions. We subsequently analyse the main biological signals in relation to changes in NH temperature and pressure anomalies. The results suggest that the main factor synchronizing regime shifts on large scales is NH temperature; however, changes in atmospheric circulation also appear important. We propose that this quasi-synchronous shift could represent the variably lagged biological response in each ecosystem to a large-scale, NH change of the climatic system, involving both an increase in NH temperature and a strongly positive phase of the Arctic Oscillation. Further investigation is needed to determine the relative roles of changes in temperature and atmospheric pressure patterns and their resultant teleconnections in synchronizing regime shifts at large scales.

  • 3. Bebbington, Jan
    et al.
    Blasiak, Robert
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Larrinaga, Carlos
    Russell, Shona
    Sobkowiak, Madlen
    Jouffray, Jean-Baptiste
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Österblom, Henrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Shaping nature outcomes in corporate settings2024Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 379, nr 1903, artikel-id 20220325Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Transnational companies have substantive impacts on nature: a hallmark of living in the Anthropocene. Understanding these impacts through company provision of information is a precursor to holding them accountable for nature outcomes. The effect of increasing disclosures (of varying quality) is predicated on 'information governance', an approach that uses disclosure requirements to drive company behaviour. However, its efficacy is not guaranteed. We argue that three conditions are required before disclosures have the possibility to shape nature outcomes, namely: (1) radical traceability that links company actions to outcomes in particular settings; (2) developing organizational routines, tools and approaches that translate strategic intent to on-the-ground behaviour; and (3) mobilizing and aligning financial actors with corporate nature ambitions. While disclosure is key to each of these conditions, its limits must be taken into account and it must be nested in governance approaches that shape action, not just reporting.This article is part of the theme issue 'Bringing nature into decision-making'.

  • 4. Berdan, Emma L.
    et al.
    Blanckaert, Alexandre
    Butlin, Roger K.
    Flatt, Thomas
    Slotte, Tanja
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    Wielstra, Ben
    Mutation accumulation opposes polymorphism: supergenes and the curious case of balanced lethals2022Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 377, nr 1856, artikel-id 20210199Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Supergenes offer spectacular examples of long-term balancing selection in nature, but their origin and maintenance remain a mystery. Reduced recombination between arrangements, a critical aspect of many supergenes, protects adaptive multi-trait phenotypes but can lead to mutation accumulation. Mutation accumulation can stabilize the system through the emergence of associative overdominance (AOD), destabilize the system, or lead to new evolutionary outcomes. One outcome is the formation of maladaptive balanced lethal systems, where only heterozygotes remain viable and reproduce. We investigated the conditions under which these different outcomes occur, assuming a scenario of introgression after divergence. We found that AOD aided the invasion of a new supergene arrangement and the establishment of a polymorphism. However, this polymorphism was easily destabilized by further mutation accumulation, which was often asymmetric, disrupting the quasi-equilibrium state. Mechanisms that accelerated degeneration tended to amplify asymmetric mutation accumulation between the supergene arrangements and vice-versa. As the evolution of balanced lethal systems requires symmetric degeneration of both arrangements, this leaves only restricted conditions for their evolution, namely small population sizes and low rates of gene conversion. The dichotomy between the persistence of polymorphism and degeneration of supergene arrangements likely underlies the rarity of balanced lethal systems in nature.This article is part of the theme issue 'Genomic architecture of supergenes: causes and evolutionary consequences'.

  • 5.
    Burian, Alfred
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik. University of Derby, UK.
    Nielsen, Jens M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Hansen, Thomas
    Bermudez, Rafael
    Winder, Monika
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    The potential of fatty acid isotopes to trace trophic transfer in aquatic food-webs2020Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 375, nr 1804, artikel-id 20190652Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Compound-specific isotope analyses (CSIA) of fatty acids (FA) constitute a promising tool for tracing energy flows in food-webs. However, past applications of FA-specific carbon isotope analyses have been restricted to a relatively coarse food-source separation and mainly quantified dietary contributions from different habitats. Our aim was to evaluate the potential of FA-CSIA to provide high-resolution data on within-system energy flows using algae and zooplankton as model organisms. First, we investigated the power of FA-CSIA to distinguish among four different algae groups, namely cyanobacteria, chlorophytes, haptophytes and diatoms. We found substantial within-group variation but also demonstrated that delta C-13 of several FA (e.g. 18:3 omega 3 or 18:4 omega 3) differed among taxa, resulting in group-specific isotopic fingerprints. Second, we assessed changes in FA isotope ratios with trophic transfer. Isotope fractionation was highly variable in daphnids and rotifers exposed to different food sources. Only delta C-13 of nutritionally valuable poly-unsaturated FA remained relatively constant, highlighting their potential as dietary tracers. The variability in fractionation was partly driven by the identity of food sources. Such systematic effects likely reflect the impact of dietary quality on consumers' metabolism and suggest that FA isotopes could be useful nutritional indicators in the field. Overall, our results reveal that the variability of FA isotope ratios provides a substantial challenge, but that FA-CSIA nevertheless have several promising applications in food-web ecology. This article is part of the theme issue 'The next horizons for lipids as 'trophic biomarkers': evidence and significance of consumer modification of dietary fatty acids'.

  • 6. Callaghan, Terry V.
    et al.
    Jonasson, Christer
    Thierfelder, Tomas
    Yang, Zhenlin
    Hedenås, Henrik
    Johansson, Margareta
    Molau, Ulf
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. University of Gothenburg, Sweden.
    Van Bogaert, Rik
    Michelsen, Anders
    Olofsson, Johan
    Gwynn-Jones, Dylan
    Bokhorst, Stef
    Phoenix, Gareth
    Bjerke, Jarle W.
    Tommervik, Hans
    Christensen, Torben R.
    Hanna, Edward
    Koller, Eva K.
    Sloan, Victoria L.
    Ecosystem change and stability over multiple decades in the Swedish subarctic: complex processes and multiple drivers2013Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 368, nr 1624Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The subarctic environment of northernmost Sweden has changed over the past century, particularly elements of climate and cryosphere. This paper presents a unique geo-referenced record of environmental and ecosystem observations from the area since 1913. Abiotic changes have been substantial. Vegetation changes include not only increases in growth and range extension but also counterintuitive decreases, and stability: all three possible responses. Changes in species composition within the major plant communities have ranged between almost no changes to almost a 50 per cent increase in the number of species. Changes in plant species abundance also vary with particularly large increases in trees and shrubs (up to 600%). There has been an increase in abundance of aspen and large changes in other plant communities responding to wetland area increases resulting from permafrost thaw. Populations of herbivores have responded to varying management practices and climate regimes, particularly changing snow conditions. While it is difficult to generalize and scale-up the site-specific changes in ecosystems, this very site-specificity, combined with projections of change, is of immediate relevance to local stakeholders who need to adapt to new opportunities and to respond to challenges. Furthermore, the relatively small area and its unique datasets are a microcosm of the complexity of Arctic landscapes in transition that remains to be documented.

  • 7. Cauchoix, M.
    et al.
    Chow, P. K. Y.
    van Horik, J. O.
    Atance, C. M.
    Barbeau, E. J.
    Barragan-Jason, G.
    Bize, P.
    Boussard, Annika
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Buechel, Severine D.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Cabirol, A.
    Cauchard, L.
    Claidiere, N.
    Dalesman, S.
    Devaud, J. M.
    Didic, M.
    Doligez, B.
    Fagot, J.
    Fichtel, C.
    Henke-von der Malsburg, J.
    Hermer, E.
    Huber, L.
    Huebner, F.
    Kappeler, P. M.
    Klein, S.
    Langbein, J.
    Langley, E. J. G.
    Lea, S. E. G.
    Lihoreau, M.
    Lovlie, H.
    Matzel, L. D.
    Nakagawa, S.
    Nawroth, C.
    Oesterwind, S.
    Sauce, B.
    Smith, E. A.
    Sorato, E.
    Tebbich, S.
    Wallis, L. J.
    Whiteside, M. A.
    Wilkinson, A.
    Chaine, A. S.
    Morand-Ferron, J.
    The repeatability of cognitive performance: a meta-analysis2018Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 373, nr 1756, artikel-id 20170281Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Behavioural and cognitive processes play important roles in mediating an individual's interactions with its environment. Yet, while there is a vast literature on repeatable individual differences in behaviour, relatively little is known about the repeatability of cognitive performance. To further our understanding of the evolution of cognition, we gathered 44 studies on individual performance of 25 species across six animal classes and used meta-analysis to assess whether cognitive performance is repeatable. We compared repeatability (R) in performance (1) on the same task presented at different times (temporal repeatability), and (2) on different tasks that measured the same putative cognitive ability (contextual repeatability). We also addressed whether R estimates were influenced by seven extrinsic factors (moderators): type of cognitive performance measurement, type of cognitive task, delay between tests, origin of the subjects, experimental context, taxonomic class and publication status. We found support for both temporal and contextual repeatability of cognitive performance, with mean R estimates ranging between 0.15 and 0.28. Repeatability estimates were mostly influenced by the type of cognitive performance measures and publication status. Our findings highlight the widespread occurrence of consistent inter-individual variation in cognition across a range of taxa which, like behaviour, may be associated with fitness outcomes. This article is part of the theme issue 'Causes and consequences of individual differences in cognitive abilities'.

  • 8. Conversi, Alessandra
    et al.
    Dakos, Vasilis
    Gårdmark, Anna
    Ling, Scott
    Folke, Carl
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. Royal Swedish Academy of Sciences, Sweden.
    Mumby, Peter J.
    Greene, Charles
    Edwards, Martin
    Blenckner, Thorsten
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Casini, Michele
    Pershing, Andrew
    Möllmann, Christian
    A holistic view of marine regime shifts2015Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, nr 1659, artikel-id 20130279Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Understanding marine regime shifts is important not only for ecology but also for developing marine management that assures the provision of ecosystem services to humanity. While regime shift theory is well developed, there is still no common understanding on drivers, mechanisms and characteristic of abrupt changes in real marine ecosystems. Based on contributions to the present theme issue, we highlight some general issues that need to be overcome for developing a more comprehensive understanding of marine ecosystem regime shifts. We find a great divide between benthic reef and pelagic ocean systems in how regime shift theory is linked to observed abrupt changes. Furthermore, we suggest that the long-lasting discussion on the prevalence of top-down trophic or bottom-up physical drivers in inducing regime shifts may be overcome by taking into consideration the synergistic interactions of multiple stressors, and the special characteristics of different ecosystem types. We present a framework for the holistic investigation of marine regime shifts that considers multiple exogenous drivers that interact with endogenous mechanisms to cause abrupt, catastrophic change. This framework takes into account the time-delayed synergies of these stressors, which erode the resilience of the ecosystem and eventually enable the crossing of ecological thresholds. Finally, considering that increased pressures in the marine environment are predicted by the current climate change assessments, in order to avoid major losses of ecosystem services, we suggest that marine management approaches should incorporate knowledge on environmental thresholds and develop tools that consider regime shift dynamics and characteristics. This grand challenge can only be achieved through a holistic view of marine ecosystem dynamics as evidenced by this theme issue.

  • 9. Currie, Thomas E.
    et al.
    Mulder, Monique Borgerhoff
    Fogarty, Laurel
    Schlüter, Maja
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Folke, Carl
    Haider, L. Jamila
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Caniglia, Guido
    Tavoni, Alessandro
    Jansen, Raf E. V.
    Søgaard Jørgensen, Peter
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. Royal Swedish Academy of Sciences, Sweden.
    Waring, Timothy M.
    Integrating evolutionary theory and social–ecological systems research to address the sustainability challenges of the Anthropocene2024Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 379, nr 1893, artikel-id 20220262Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The rapid, human-induced changes in the Earth system during the Anthropocene present humanity with critical sustainability challenges. Social–ecological systems (SES) research provides multiple approaches for understanding the complex interactions between humans, social systems, and environments and how we might direct them towards healthier and more resilient futures. However, general theories of SES change have yet to be fully developed. Formal evolutionary theory has been applied as a dynamic theory of change of complex phenomena in biology and the social sciences, but rarely in SES research. In this paper, we explore the connections between both fields, hoping to foster collaboration. After sketching out the distinct intellectual traditions of SES research and evolutionary theory, we map some of their terminological and theoretical connections. We then provide examples of how evolutionary theory might be incorporated into SES research through the use of systems mapping to identify evolutionary processes in SES, the application of concepts from evolutionary developmental biology to understand the connections between systems changes and evolutionary changes, and how evolutionary thinking may help design interventions for beneficial change. Integrating evolutionary theory and SES research can lead to a better understanding of SES changes and positive interventions for a more sustainable Anthropocene.

  • 10. De Dreu, Carsten K. W.
    et al.
    Triki, Zegni
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Intergroup conflict: Origins, dynamics and consequences across taxa2022Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 377, nr 1851, s. 332-342Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Although uniquely destructive and wasteful, intergroup conflict and warfare are not confined to humans. They are seen across a range of group-living species, from social insects, fishes and birds to mammals, including nonhuman primates. With its unique collection of theory, research and review contributions from biology, anthropology and economics, this theme issue provides novel insights into intergroup conflict across taxa. Here, we introduce and organize this theme issue on the origins and consequences of intergroup conflict. We provide a coherent framework by modelling intergroup conflicts as multi-level games of strategy in which individuals within groups cooperate to compete with (individuals in) other groups for scarce resources, such as territory, food, mating opportunities, power and influence. Within this framework, we identify cross-species mechanisms and consequences of (participating in) intergroup conflict. We conclude by highlighting crosscutting innovations in the study of intergroup conflict set forth by individual contributions. These include, among others, insights on how within-group heterogeneities and leadership relate to group conflict, how intergroup conflict shapes social organization and how climate change and environmental degradation transition intergroup relations from peaceful coexistence to violent conflict.

  • 11.
    Enquist, Magnus
    et al.
    Stockholms universitet, Humanistiska fakulteten, Centrum för evolutionär kulturforskning. Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Ghirlanda, Stefano
    Stockholms universitet, Humanistiska fakulteten, Centrum för evolutionär kulturforskning.
    Eriksson, Kimmo
    Stockholms universitet, Humanistiska fakulteten, Centrum för evolutionär kulturforskning.
    Modelling the evolution and diversity of cumulative culture2011Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 366, nr 1563, s. 412-423Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Previous work on mathematical models of cultural evolution has mainly focused on the diffusion of simple cultural elements. However, a characteristic feature of human cultural evolution is the seemingly limitless appearance of new and increasingly complex cultural elements. Here, we develop a general modelling framework to study such cumulative processes, in which we assume that the appearance and disappearance of cultural elements are stochastic events that depend on the current state of culture. Five scenarios are explored: evolution of independent cultural elements, stepwise modification of elements, differentiation or combination of elements and systems of cultural elements. As one application of our framework, we study the evolution of cultural diversity (in time as well as between groups).

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  • 12.
    Faye, Ingrid
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för molekylär biovetenskap, Wenner-Grens institut.
    Lindberg, Bo G.
    Towards a paradigm shift in innate immunity-seminal work by Hans G. Boman and co-workers2016Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 371, nr 1695, artikel-id 20150303Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Four decades ago, immunological research was dominated by the field of lymphoid biology. It was commonly accepted that multicellular eukaryotes defend themselves through phagocytosis. The lack of lymphoid cells in insects and other simpler animals, however, led to the common notion that they might simply lack the capacity defend themselves with humoral factors. This view was challenged by microbiologist Hans G. Boman and co-workers in a series of publications that led to the advent of antimicrobial peptides as a universal arm of the immune system. Besides ingenious research, Boman ignited his work by posing the right questions. He started off by asking himself a simple question: 'Antibodies take weeks to produce while many microbes divide hourly; so how come we stay healthy?'. This led to two key findings in the field: the discovery of an inducible and highly potent antimicrobial immune response in Drosophila in 1972, followed by the characterization of cecropin in 1981. Despite broadly being considered an insect-specific response at first, the work of Boman and co-workers eventually created a bandwagon effect that unravelled various aspects of innate immunity. This article is part of the themed issue 'Evolutionary ecology of arthropod antimicrobial peptides'.

  • 13.
    Fitzpatrick, John L.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Sperm competition and fertilization mode in fishes2020Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 375, nr 1813, artikel-id 20200074Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Sperm competition is a powerful selective force that has shaped sexual traits throughout animal evolution. Yet, how fertilization mode (i.e. external versus internal fertilization) influences the scope and potential for sperm competition to act on ejaculates remains unclear. Here, I examine how fertilization mode shapes ejaculatory responses to sperm competition in fishes, a diverse group that constitute the majority of vertebrate biological diversity. Fishes are an ideal group for this examination because they exhibit a wide range of reproductive behaviours and an unparalleled number of transitions in fertilization mode compared to any other vertebrate group. Drawing on data from cartilaginous and bony fishes, I first show that rates of multiple paternity are higher in internally than externally fertilizing fishes, contrary to the prevailing expectation. I then summarize how sperm competition acts on sperm number and quality in internally and externally fertilizing fishes, highlighting where theoretical predictions differ between these groups. Differences in how ejaculates respond to sperm competition between fertilization modes are most apparent when considering sperm size and swimming performance. Clarifying how fertilization mode influences evolutionary responses in ejaculates will inform our understanding of ejaculate evolution across the animal tree of life. This article is part of the theme issue 'Fifty years of sperm competition'.

  • 14. Friesen, Christopher R.
    et al.
    Kahrl, Ariel F.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Olsson, Mats
    Sperm competition in squamate reptiles2020Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 375, nr 1813, artikel-id 20200079Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Multiple paternity is ubiquitous within the polyphyletic group called 'reptiles', especially within the lizards and snakes. Therefore, the probability of sperm competition occurring, and being intense, is high. Squamates exhibit a diversity of tactics to ensure fertilization success in the face of sperm competition. The duration of female sperm storage, which can be many months and even years in some species, remains an enigma. Here, we emphasize some mechanisms that might affect patterns of paternity, the source and function of ejaculates and features of the female reproductive tract that may aid in long-term sperm storage. In doing so, we present a new analysis of the relationship between sperm size, the strength of sperm competition and the duration of female sperm storage. Lizards and snakes are a diverse group that has provided many excellent models for the study of an array of life-history strategies. However, when it comes to postcopulatory sexual selection, there is much left to discover. This article is part of the theme issue 'Fifty years of sperm competition'.

  • 15. Garlovsky, Martin D.
    et al.
    Yusuf, Leeban H.
    Ritchie, Michael G.
    Snook, Rhonda R.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Within-population sperm competition intensity does not predict asymmetry in conpopulation sperm precedence2020Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 375, nr 1813, artikel-id 20200071Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Postcopulatory sexual selection can generate evolutionary arms races between the sexes resulting in the rapid coevolution of reproductive phenotypes. As traits affecting fertilization success diverge between populations, postmating prezygotic (PMPZ) barriers to gene flow may evolve. Conspecific sperm precedence is a form of PMPZ isolation thought to evolve early during speciation yet has mostly been studied between species. Here, we show conpopulation sperm precedence (CpSP) between Drosophila montana populations. Using Pool-seq genomic data we estimate divergence times and ask whether PMPZ isolation evolved in the face of gene flow. We find models incorporating gene flow fit the data best indicating populations experienced considerable gene flow during divergence. We find CpSP is asymmetric and mirrors asymmetry in non-competitive PMPZ isolation, suggesting these phenomena have a shared mechanism. However, we show asymmetry is unrelated to the strength of postcopulatory sexual selection acting within populations. We tested whether overlapping foreign and coevolved ejaculates within the female reproductive tract altered fertilization success but found no effect. Our results show that neither time since divergence nor sperm competitiveness predicts the strength of PMPZ isolation. We suggest that instead cryptic female choice or mutation-order divergence may drive divergence of postcopulatory phenotypes resulting in PMPZ isolation. This article is part of the theme issue 'Fifty years of sperm competition'.

  • 16.
    Ghirlanda, Stefano
    et al.
    Stockholms universitet, Humanistiska fakulteten, Centrum för evolutionär kulturforskning.
    Frasnelli, Elisa
    Vallortigara, Giorgio
    Intraspecific competition and coordination in the evolution of lateralization2009Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, nr 1519, s. 861-866Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent studies have revealed a variety of left-right asymmetries among vertebrates and invertebrates. In many species, left-and right-lateralized individuals coexist, but in unequal numbers ('populationlevel' lateralization). It has been argued that brain lateralization increases individual efficiency (e. g. avoiding unnecessary duplication of neural circuitry and reducing interference between functions), thus counteracting the ecological disadvantages of lateral biases in behaviour (making individual behaviour more predictable to other organisms). However, individual efficiency does not require a definite proportion of left-and right-lateralized individuals. Thus, such arguments do not explain population-level lateralization. We have previously shown that, in the context of prey-predator interactions, population-level lateralization can arise as an evolutionarily stable strategy when individually asymmetrical organisms must coordinate their behaviour with that of other asymmetrical organisms. Here, we extend our model showing that populations consisting of left-and right-lateralized individuals in unequal numbers can be evolutionarily stable, based solely on strategic factors arising from the balance between antagonistic (competitive) and synergistic (cooperative) interactions.

  • 17.
    Höök, Kristina
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Affective loop experiences: designing for interactional embodiment2009Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, nr 1535, s. 3585-3595Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Involving our corporeal bodies in interaction can create strong affective experiences. Systems that both can be influenced by and influence users corporeally exhibit a use quality we name an affective loop experience. In an affective loop experience, (i) emotions are seen as processes, constructed in the interaction, starting from everyday bodily, cognitive or social experiences; (ii) the system responds in ways that pull the user into the interaction, touching upon end users’ physical experiences; and (iii) throughout the interaction the user is an active, meaning-making individual choosing how to express themselves—the interpretation responsibility does not lie with the system. We have built several systems that attempt to create affective loop experiences with more or less successful results. For example, eMoto lets users send text messages between mobile phones, but in addition to text, the messages also have colourful and animated shapes in the background chosen through emotion-gestures with a sensor-enabled stylus pen. Affective Diary is a digital diary with which users can scribble their notes, but it also allows for bodily memorabilia to be recorded from body sensors mapping to users’ movement and arousal and placed along a timeline. Users can see patterns in their bodily reactions and relate them to various events going on in their lives. The experiences of building and deploying these systems gave us insights into design requirements for addressing affective loop experiences, such as how to design for turn-taking between user and system, how to create for ‘open’ surfaces in the design that can carry users’ own meaning-making processes, how to combine modalities to create for a ‘unity’ of expression, and the importance of mirroring user experience in familiar ways that touch upon their everyday social and corporeal experiences. But a more important lesson gained from deploying the systems is how emotion processes are co-constructed and experienced inseparable from all other aspects of everyday life. Emotion processes are part of our social ways of being in the world; they dye our dreams, hopes and bodily experiences of the world. If we aim to design for affective interaction experiences, we need to place them into this larger picture.

  • 18.
    Jansson, Fredrik
    et al.
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur, Centrum för evolutionär kulturforskning. Mälardalen University, Sweden.
    Aguilar, Elliot
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur, Centrum för evolutionär kulturforskning.
    Acerbi, Alberto
    Enquist, Magnus
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur, Centrum för evolutionär kulturforskning. Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Modelling cultural systems and selective filters2021Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 376, nr 1828, artikel-id 20200045Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A specific goal of the field of cultural evolution is to understand how processes of transmission and selection at the individual level lead to population-wide patterns of cultural diversity and change. Models of cultural evolution have typically assumed that traits are independent of one another and essentially exchangeable. But culture has a structure: traits bear relationships to one another that affect the transmission and selection process itself. Here, we introduce a modelling framework to explore the effect of interdependencies on the process of learning. Through simulations, we find that introducing a simple structure changes the cultural dynamics. Based on a basic filtering mechanism for parsing trait relationships, more elaborate cultural filters emerge. In a mostly incompatible cultural domain of traits, these filters organize culture into mostly (but not fully) consistent and stable systems. Incompatible domains produce small homogeneous cultures, while more compatibility increases size, diversity and group divergence. When individuals copy based on a trait's features (here, its compatibility relationships), they produce more homogeneous cultures than when they copy based on the agent carrying the cultural trait. We discuss the implications of considering cultural systems and filters in the dynamics of cultural change. This article is part of the theme issue 'Foundations of cultural evolution'.

  • 19.
    Jastroch, Martin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för molekylär biovetenskap, Wenner-Grens institut.
    Seebacher, Frank
    Importance of adipocyte browning in the evolution of endothermy2020Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 375, nr 1793, artikel-id 20190134Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Endothermy changes the relationship between organisms and their environment fundamentally, and it is therefore of major ecological and evolutionary significance. Endothermy is characterized by non-shivering thermogenesis, that is metabolic heat production in the absence of muscular activity. In many eutherian mammals, brown adipose tissue (BAT) is an evolutionary innovation that facilitates non-shivering heat production in mitochondria by uncoupling food-derived substrate oxidation from chemical energy (ATP) production. Consequently, energy turnover is accelerated resulting in increased heat release. The defining characteristics of BAT are high contents of mitochondria and vascularization, and the presence of uncoupling protein 1. Recent insights, however, reveal that a range of stimuli such as exercise, diet and the immune system can cause the browning of white adipocytes, thereby increasing energy expenditure and heat production even in the absence of BAT. Here, we review the molecular mechanisms that cause browning of white adipose tissue, and their potential contribution to thermoregulation. The significance for palaeophysiology lies in the presence of adipose tissue and the mechanisms that cause its browning and uncoupling in all amniotes. Hence, adipocytes may have played a role in the evolution of endothermy beyond the more specific evolution of BAT in eutherians. This article is part of the theme issue 'Vertebrate palaeophysiology'.

  • 20. Jickells, T.
    et al.
    Baker, A. R.
    Cape, J. N.
    Cornell, Sarah
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Nemitz, E.
    The cycling of organic nitrogen through the atmosphere2013Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 368, nr 1621Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Atmospheric organic nitrogen (ON) appears to be a ubiquitous but poorly understood component of the atmospheric nitrogen deposition flux. Here, we focus on the ON components that dominate deposition and do not consider reactive atmospheric gases containing ON such as peroxyacyl nitrates that are important in atmospheric nitrogen transport, but are probably not particularly important in deposition. We first review the approaches to the analysis and characterization of atmospheric ON. We then briefly summarize the available data on the concentrations of ON in both aerosols and rainwater from around the world, and the limited information available on its chemical characterization. This evidence clearly shows that atmospheric aerosol and rainwater ON is a complex mixture of material from multiple sources. This synthesis of available information is then used to try and identify some of the important sources of this material, in particular, if it is of predominantly natural or anthropogenic origin. Finally, we suggest that the flux of ON is about 25 per cent of the total nitrogen deposition flux.

  • 21. Jombart, Thibaut
    et al.
    Ghozzi, Stéphane
    Schumacher, Dirk
    Taylor, Timothy J.
    Leclerc, Quentin J.
    Jit, Mark
    Flasche, Stefan
    Greaves, Felix
    Ward, Tom
    Eggo, Rosalind M.
    Nightingale, Emily
    Meakin, Sophie
    Brady, Oliver J.
    Medley, Graham F.
    Höhle, Michael
    Stockholms universitet, Naturvetenskapliga fakulteten, Matematiska institutionen.
    Edmunds, W. John
    Real-time monitoring of COVID-19 dynamics using automated trend fitting and anomaly detection2021Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 376, nr 1829, artikel-id 20200266Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    As several countries gradually release social distancing measures, rapid detection of new localized COVID-19 hotspots and subsequent intervention will be key to avoiding large-scale resurgence of transmission. We introduce ASMODEE (automatic selection of models and outlier detection for epidemics), a new tool for detecting sudden changes in COVID-19 incidence. Our approach relies on automatically selecting the best (fitting or predicting) model from a range of user-defined time series models, excluding the most recent data points, to characterize the main trend in an incidence. We then derive prediction intervals and classify data points outside this interval as outliers, which provides an objective criterion for identifying departures from previous trends. We also provide a method for selecting the optimal breakpoints, used to define how many recent data points are to be excluded from the trend fitting procedure. The analysis of simulated COVID-19 outbreaks suggests ASMODEE compares favourably with a state-of-art outbreak-detection algorithm while being simpler and more flexible. As such, our method could be of wider use for infectious disease surveillance. We illustrate ASMODEE using publicly available data of National Health Service (NHS) Pathways reporting potential COVID-19 cases in England at a fine spatial scale, showing that the method would have enabled the early detection of the flare-ups in Leicester and Blackburn with Darwen, two to three weeks before their respective lockdown. ASMODEE is implemented in the free R package trendbreaker.

  • 22.
    Jouffray, Jean-Baptiste
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. Royal Swedish Academy of Sciences, Sweden.
    Nyström, Magnus
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Norström, Albert V.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Williams, Ivor D.
    Wedding, Lisa M.
    Kittinger, John N.
    Williams, Gareth J.
    Identifying multiple coral reef regimes and their drivers across the Hawaiian archipelago2015Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, nr 1659, artikel-id 20130268Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Loss of coral reef resilience can lead to dramatic changes in benthic structure, often called regime shifts, which significantly alter ecosystem processes and functioning. In the face of global change and increasing direct human impacts, there is an urgent need to anticipate and prevent undesirable regime shifts and, conversely, to reverse shifts in already degraded reef systems. Such challenges require a better understanding of the human and natural drivers that support or undermine different reef regimes. The Hawaiian archipelago extends across a wide gradient of natural and anthropogenic conditions and provides us a unique opportunity to investigate the relationships between multiple reef regimes, their dynamics and potential drivers. We applied a combination of exploratory ordination methods and inferential statistics to one of the most comprehensive coral reef datasets available in order to detect, visualize and define potential multiple ecosystem regimes. This study demonstrates the existence of three distinct reef regimes dominated by hard corals, turf algae or macroalgae. Results from boosted regression trees show nonlinear patterns among predictors that help to explain the occurrence of these regimes, and highlight herbivore biomass as the key driver in addition to effluent, latitude and depth.

  • 23. Keesstra, Saskia
    et al.
    Sannigrahi, Srikanta
    López-Vicente, Manuel
    Pulido, Manuel
    Novara, Agata
    Visser, Saskia
    Kalantari, Zahra
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi. Sustainability Science and Engineering (SEED), Sweden.
    The role of soils in regulation and provision of blue and green water2021Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 376, nr 1834, artikel-id 20200175Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The United Nations Sustainable Development Goal 6 aims for clean water and sanitation for all by 2030, through eight subgoals dealing with four themes: (i) water quantity and availability, (ii) water quality, (iii) finding sustainable solutions and (iv) policy and governance. In this opinion paper, we assess how soils and associated land and water management can help achieve this goal, considering soils at two scales: local soil health and healthy landscapes. The merging of these two viewpoints shows the interlinked importance of the two scales. Soil health reflects the capacity of a soil to provide ecosystem services at a specific location, taking into account local climate and soil conditions. Soil is also an important component of a healthy and sustainable landscape, and they are connected by the water that flows through the soil and the transported sediments. Soils are linked to water in two ways: through plant-available water in the soil (green water) and through water in surface bodies or available as groundwater (blue water). In addition, water connects the soil scale and the landscape scale by flowing through both. Nature-based solutions at both soil health and landscape-scale can help achieve sustainable future development but need to be embedded in good governance, social acceptance and economic viability.

  • 24. Krams, Indrikis
    et al.
    Krama, Tatjana
    Freeberg, Todd M.
    Kullberg, Cecilia
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Lucas, Jeffrey R.
    Linking social complexity and vocal complexity: a parid perspective2012Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 367, nr 1597, s. 1879-1891Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The Paridae family (chickadees, tits and titmice) is an interesting avian group in that species vary in important aspects of their social structure and many species have large and complex vocal repertoires. For this reason, parids represent an important set of species for testing the social complexity hypothesis for vocal communication-the notion that as groups increase in social complexity, there is a need for increased vocal complexity. Here, we describe the hypothesis and some of the early evidence that supported the hypothesis. Next, we review literature on social complexity and on vocal complexity in parids, and describe some of the studies that have made explicit tests of the social complexity hypothesis in one parid-Carolina chickadees, Poecile carolinensis. We conclude with a discussion, primarily from a parid perspective, of the benefits and costs of grouping and of physiological factors that might mediate the relationship between social complexity and changes in signalling behaviour.

  • 25. Krause, J.
    et al.
    Herbert-Read, James E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Uppsala University, Sweden.
    Seebacher, F.
    Domenici, P.
    Wilson, Alexander D. M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Germany.
    Marras, S.
    Svendsen, M. B. S.
    Strömbom, D.
    Steffensen, J. F.
    Krause, S.
    Viblanc, P. E.
    Couillaud, P.
    Bach, P.
    Sabarros, P. S.
    Zaslansky, P.
    Kurvers, R. H. J. M.
    Injury-mediated decrease in locomotor performance increases predation risk in schooling fish2017Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 372, nr 1727, artikel-id 20160232Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The costs and benefits of group living often depend on the spatial position of individuals within groups and the ability of individuals to occupy preferred positions. For example, models of predation events for moving prey groups predict higher mortality risk for individuals at the periphery and front of groups. We investigated these predictions in sardine (Sardinella aurita) schools under attack from group hunting sailfish (Istiophorus platypterus) in the open ocean. Sailfish approached sardine schools about equally often from the front and rear, but prior to attack there was a chasing period in which sardines attempted to swim away from the predator. Consequently, all sailfish attacks were directed at the rear and peripheral positions of the school, resulting in higher predation risk for individuals at these positions. During attacks, sailfish slash at sardines with their bill causing prey injury including scale removal and tissue damage. Sardines injured in previous attacks were more often found in the rear half of the school than in the front half. Moreover, injured fish had lower tail-beat frequencies and lagged behind uninjured fish. Injuries inflicted by sailfish bills may, therefore, hinder prey swimming speed and drive spatial sorting in prey schools through passive self-assortment. We found only partial support for the theoretical predictions from current predator-prey models, highlighting the importance of incorporating more realistic predator-prey dynamics into these models. This article is part of the themed issue 'Physiological determinants of social behaviour in animals'.

  • 26.
    Krzewińska, Maja
    et al.
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur, Arkeologiska forskningslaboratoriet. University of Oslo, Norway.
    Bjørnstad, Gro
    Skoglund, Pontus
    Olason, Pall Isolfur
    Bill, Jan
    Götherström, Anders
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur, Arkeologiska forskningslaboratoriet. Uppsala University, Sweden.
    Hagelberg, Erika
    Mitochondrial DNA variation in the Viking age population of Norway2015Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, nr 1660, artikel-id 20130384Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The medieval Norsemen or Vikings had an important biological and cultural impact on many parts of Europe through raids, colonization and trade, from about AD 793 to 1066. To help understand the genetic affinities of the ancient Norsemen, and their genetic contribution to the gene pool of other Europeans, we analysed DNA markers in Late Iron Age skeletal remains from Norway. DNA was extracted from 80 individuals, and mitochondrial DNA polymorphisms were detected by next-generation sequencing. The sequences of 45 ancient Norwegians were verified as genuine through the identification of damage patterns characteristic of ancient DNA. The ancient Norwegians were genetically similar to previously analysed ancient Icelanders, and to present-day Shetland and Orkney Islanders, Norwegians, Swedes, Scots, English, German and French. The Viking Age population had higher frequencies of K*, U*, V* and I* haplogroups than their modern counterparts, but a lower proportion of T* and H* haplogroups. Three individuals carried haplotypes that are rare in Norway today (U5b1b1, Hg A* and an uncommon variant of H*). Our combined analyses indicate that Norse women were important agents in the overseas expansion and settlement of the Vikings, and that women from the Orkneys and Western Isles contributed to the colonization of Iceland.

  • 27. Kuijper, Bram
    et al.
    Leimar, Olof
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Hammerstein, Peter
    McNamara, John M.
    Dall, Sasha R. X.
    The evolution of social learning as phenotypic cue integration2021Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 376, nr 1828, artikel-id 20200048Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Most analyses of the origins of cultural evolution focus on when and where social learning prevails over individual learning, overlooking the fact that there are other developmental inputs that influence phenotypic fit to the selective environment. This raises the question of how the presence of other cue ‘channels’ affects the scope for social learning. Here, we present a model that considers the simultaneous evolution of (i) multiple forms of social learning (involving vertical or horizontal learning based on either prestige or conformity biases) within the broader context of other evolving inputs on phenotype determination, including (ii) heritable epigenetic factors, (iii) individual learning, (iv) environmental and cascading maternal effects, (v) conservative bet-hedging, and (vi) genetic cues. In fluctuating environments that are autocorrelated (and hence predictable), we find that social learning from members of the same generation (horizontal social learning) explains the large majority of phenotypic variation, whereas other cues are much less important. Moreover, social learning based on prestige biases typically prevails in positively autocorrelated environments, whereas conformity biases prevail in negatively autocorrelated environments. Only when environments are unpredictable or horizontal social learning is characterized by an intrinsically low information content, other cues such as conservative bet-hedging or vertical prestige biases prevail.

    This article is part of the theme issue ‘Foundations of cultural evolution’.

  • 28.
    Lansing, J. Stephen
    et al.
    Stockholms universitet, Stockholm Resilience Centre.
    Fox, Karyn M.
    Niche construction on Bali: the gods of the countryside2011Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 366, nr 1566, s. 927-34Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Human niche construction encompasses both purely biological phenomena, such as the evolution of lactose tolerance, and dual inheritance theory, which investigates the transmission of cultural information. But does niche construction help to explain phenomena in which conscious intention also plays a role? The creation of the engineered landscape of Balinese rice terraces offers a test case. Population genetic analysis and archaeological evidence are used to investigate whether this phenomenon emerged historically from trial and error by generations of farmers, or alternatively was designed by Bali's rulers. In light of strong support for the former hypothesis, two models are developed to explore the emergence of functional structure at both local and global scales. As time goes forward and selected patterns of irrigation schedules are implemented, local variation in rice harvests influences future decisions by the farmers, creating a coupled human-natural system governed by feedback from the environment. This mathematical analysis received a measure of empirical support when government agricultural policies severed the local feedback channels, resulting in the almost instantaneous collapse of rice harvests. The historical process of niche construction may also have included an evolution of religious consciousness, reflected in the beliefs and practices of the water temple cult.

  • 29.
    Larsson, Petter
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    von Seth, Johanna
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    Hagen, Ingerid J.
    Götherström, Anders
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur.
    Androsov, Semyon
    Germonpre, Mietje
    Bergfeldt, Nora
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    Fedorov, Sergey
    Eide, Nina E.
    Sokolova, Natalia
    Berteaux, Dominique
    Angerbjörn, Anders
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Flagstad, Øystein
    Plotnikov, Valeri
    Norén, Karin
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Díez-del-Molino, David
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    Dussex, Nicolas
    Stanton, David W. G.
    Dalén, Love
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    Consequences of past climate change and recent human persecution on mitogenomic diversity in the arctic fox2019Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 374, nr 1788, artikel-id 20190212Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ancient DNA provides a powerful means to investigate the timing, rate and extent of population declines caused by extrinsic factors, such as past climate change and human activities. One species probably affected by both these factors is the arctic fox, which had a large distribution during the last glaciation that subsequently contracted at the start of the Holocene. More recently, the arctic fox population in Scandinavia went through a demographic bottleneck owing to human persecution. To investigate the consequences of these processes, we generated mitogenome sequences from a temporal dataset comprising Pleistocene, historical and modern arctic fox samples. We found no evidence that Pleistocene populations in mid-latitude Europe or Russia contributed to the present-day gene pool of the Scandinavian population, suggesting that postglacial climate warming led to local population extinctions. Furthermore, during the twentieth-century bottleneck in Scandinavia, at least half of the mitogenome haplotypes were lost, consistent with a 20-fold reduction in female effective population size. In conclusion, these results suggest that the arctic fox in mainland Western Europe has lost genetic diversity as a result of both past climate change and human persecution. Consequently, it might be particularly vulnerable to the future challenges posed by climate change. This article is part of a discussion meeting issue 'The past is a foreign country: how much can the fossil record actually inform conservation?'

  • 30.
    Leimar, Olof
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    McNamara, John M.
    Game theory in biology: 50 years and onwards2023Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Philosophical Transactions of the Royal Society B, ISSN 0962-8436, Vol. 378, nr 1876, artikel-id 20210509Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Game theory in biology gained prominence 50 years ago, when Maynard Smith & Price formulated the concept of an evolutionarily stable strategy (ESS). Their aim was to explain why conflicts between animals of the same species usually are of a ‘limited war’ type, not causing serious injury. They emphasized that game theory is an alternative to previous ideas about group selection, which were used by ethologists to explain limited aggression. Subsequently, the ESS concept was applied to many phenomena with frequency dependence in the evolutionary success of strategies, including sex allocation, alternative mating types, contest behaviour and signalling, cooperation, and parental care. Both the analyses of signalling and cooperation were inspired by similar problems in economics and attracted much attention in biology. Here we give a perspective on which of the ambitions in the field have been achieved, with a focus on contest behaviour and cooperation. We evaluate whether the game-theoretical study of the evolution of cooperation has measured up to expectations in explaining the behaviour of non-human animals. We also point to potentially fruitful directions for the field, and emphasize the importance of incorporating realistic behavioural mechanisms into models.

  • 31. Lenton, Timothy M.
    et al.
    Buxton, Joshua E.
    Armstrong McKay, David I.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. University of Exeter, UK.
    Abrams, Jesse F.
    Boulton, Chris A.
    Lees, Kirsten
    Powell, Thomas W. R.
    Boers, Niklas
    Cunliffe, Andrew M.
    Dakos, Vasilis
    A resilience sensing system for the biosphere2022Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 377, nr 1857, artikel-id 20210383Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We are in a climate and ecological emergency, where climate change and direct anthropogenic interference with the biosphere are risking abrupt and/or irreversible changes that threaten our life-support systems. Efforts are underway to increase the resilience of some ecosystems that are under threat, yet collective awareness and action are modest at best. Here, we highlight the potential for a biosphere resilience sensing system to make it easier to see where things are going wrong, and to see whether deliberate efforts to make things better are working. We focus on global resilience sensing of the terrestrial biosphere at high spatial and temporal resolution through satellite remote sensing, utilizing the generic mathematical behaviour of complex systems—loss of resilience corresponds to slower recovery from perturbations, gain of resilience equates to faster recovery. We consider what subset of biosphere resilience remote sensing can monitor, critically reviewing existing studies. Then we present illustrative, global results for vegetation resilience and trends in resilience over the last 20 years, from both satellite data and model simulations. We close by discussing how resilience sensing nested across global, biome-ecoregion, and local ecosystem scales could aid management and governance at these different scales, and identify priorities for further work.

  • 32. Lüpold, Stefan
    et al.
    de Boer, Raïssa A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Evans, Jonathan P.
    Tomkins, Joseph L.
    Fitzpatrick, John L.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    How sperm competition shapes the evolution of testes and sperm: a meta-analysis2020Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 375, nr 1813, artikel-id 20200064Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Females of many species mate with multiple males, thereby inciting competition among ejaculates from rival males for fertilization. In response to increasing sperm competition, males are predicted to enhance their investment in sperm production. This prediction is so widespread that testes size (correcting for body size) is commonly used as a proxy of sperm competition, even in the absence of any other information about a species' reproductive behaviour. By contrast, a debate about whether sperm competition selects for smaller or larger sperm has persisted for nearly three decades, with empirical studies demonstrating every possible response. Here, we synthesize nearly 40 years of sperm competition research in a meta-analytical framework to determine how the evolution of sperm number (i.e. testes size) and sperm size (i.e. sperm head, midpiece, flagellum and total length) is influenced by varying levels of sperm competition across species. Our findings support the long-held assumption that higher levels of sperm competition are associated with relatively larger testes. We also find clear evidence that sperm competition is associated with increases in all components of sperm length. We discuss these results in the context of different theoretical predictions and general patterns in the breeding biology and selective environment of sperm. This article is part of the theme issue 'Fifty years of sperm competition'.

  • 33. Malmström, Helena
    et al.
    Linderholm, Anna
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur. Durham University, UK.
    Skoglund, Pontus
    Storå, Jan
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur.
    Sjödin, Per
    Gilbert, M. Thomas P.
    Holmlund, Gunilla
    Willerslev, Eske
    Jakobsson, Mattias
    Lidén, Kerstin
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur.
    Götherstrom, Anders
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur. Uppsala University, Sweden.
    Ancient mitochondrial DNA from the northern fringe of the Neolithic farming expansion in Europe sheds light on the dispersion process2015Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, nr 1660, artikel-id 20130373Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The European Neolithization process started around 12 000 years ago in the Near East. The introduction of agriculture spread north and west throughout Europe and a key question has been if this was brought about by migrating individuals, by an exchange of ideas or a by a mixture of these. The earliest farming evidence in Scandinavia is found within the Funnel Beaker Culture complex (Trichterbecherkultur, TRB) which represents the northernmost extension of Neolithic farmers in Europe. The TRB coexisted for almost a millennium with hunter-gatherers of the Pitted Ware Cultural complex (PWC). If migration was a substantial part of the Neolithization, even the northerly TRB community would display a closer genetic affinity to other farmer populations than to hunter-gatherer populations. We deep-sequenced the mitochondrial hypervariable region 1 from seven farmers (six TRB and one Battle Axe complex, BAC) and 13 hunter-gatherers (PWC) and authenticated the sequences using postmortem DNA damage patterns. A comparison with 124 previously published sequences from prehistoric Europe shows that the TRB individuals share a close affinity to Central European farmer populations, and that they are distinct from hunter-gatherer groups, including the geographically close and partially contemporary PWC that show a close affinity to the European Mesolithic hunter-gatherers.

  • 34. Mendez, Derek
    et al.
    Lane, Thomas J.
    Sung, Jongmin
    Sellberg, Jonas
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum. SLAC National Accelerator Laboratory, USA.
    Levard, Clement
    Watkins, Herschel
    Cohen, Aina E.
    Soltis, Michael
    Sutton, Shirley
    Spudich, James
    Pande, Vijay
    Ratner, Daniel
    Doniach, Sebastian
    Observation of correlated X-ray scattering at atomic resolution2014Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 369, nr 1647, s. 20130315-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tools to study disordered systems with local structural order, such as proteins in solution, remain limited. Such understanding is essential for e. g. rational drug design. Correlated X-ray scattering (CXS) has recently attracted new interest as a way to leverage next-generation light sources to study such disordered matter. The CXS experiment measures angular correlations of the intensity caused by the scattering of X-rays from an ensemble of identical particles, with disordered orientation and position. Averaging over 15 496 snapshot images obtained by exposing a sample of silver nanoparticles in solution to a micro-focused synchrotron radiation beam, we report on experimental efforts to obtain CXS signal from an ensemble in three dimensions. A correlation function was measured at wide angles corresponding to atomic resolution that matches theoretical predictions. These preliminary results suggest that other CXS experiments on disordered ensembles-such as proteins in solution-may be feasible in the future.

  • 35.
    Nedergaard, Jan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för molekylär biovetenskap, Wenner-Grens institut.
    von Essen, Gabriella
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för molekylär biovetenskap, Wenner-Grens institut.
    Cannon, Barbara
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för molekylär biovetenskap, Wenner-Grens institut.
    Brown adipose tissue: can it keep us slim? A discussion of the evidence for and against the existence of diet-induced thermogenesis in mice and men2023Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 378, nr 1888, artikel-id 20220220Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The issue under discussion here is whether a decrease in the degree of UCP1 activity (and brown adipose tissue activity in general) could be a cause of obesity in humans. This possibility principally requires the existence of the phenomenon of diet-induced thermogenesis. Obesity could be a consequence of a reduced functionality of diet-induced thermogenesis. Experiments in mice indicate that diet-induced thermogenesis exists and is dependent on the presence of UCP1 and thus of brown adipose tissue activity. Accordingly, many (but not all) experiments indicate that in the absence of UCP1, mice become obese. Whether similar mechanisms exist in humans is still unknown. A series of studies have indicated a correlation between obesity and low brown adipose tissue activity, but it may be so that the obesity itself may influence the estimates of brown adipose tissue activity (generally glucose uptake), partly explaining the relationship. Estimates of brown adipose tissue catabolizing activity would seem to indicate that it may possess a capacity sufficient to help maintain body weight, and obesity would thus be aggravated in its absence.

  • 36. Nunn, Charles L
    et al.
    Lindenfors, Patrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Stockholms universitet, Humanistiska fakulteten, Centrum för evolutionär kulturforskning.
    Pursall, E. Rhiannon
    Rolff, Jens
    On sexual dimorphism in immune function2009Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, nr 1513, s. 61-69Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sexual dimorphism in immune function is a common pattern in vertebrates and also in a number of invertebrates. Most often, females are more ‘immunocompetent’ than males. The underlying causes are explained by either the role of immunosuppressive substances, such as testosterone, or by fundamental differences in male and female life histories. Here, we investigate some of the main predictions of the immunocompetence handicap hypothesis (ICHH) in a comparative framework using mammals. We focus specifically on the prediction that measures of sexual competition across species explain the observed patterns of variation in sex-specific immunocompetence within species. Our results are not consistent with the ICHH, but we do find that female mammals tend to have higher white blood cell counts (WBC), with some further associations between cell counts and longevity in females. We also document positive covariance between sexual dimorphism in immunity, as measured by a subset of WBC, and dimorphism in the duration of effective breeding. This is consistent with the application of ‘Bateman's principle’ to immunity, with females maximizing fitness by lengthening lifespan through greater investment in immune defences. Moreover, we present a meta-analysis of insect immunity, as the lack of testosterone in insects provides a means to investigate Bateman's principle for immunity independently of the ICHH. Here, we also find a systematic female bias in the expression of one of the two components of insect immune function that we investigated (phenoloxidase). From these analyses, we conclude that the mechanistic explanations of the ICHH lack empirical support. Instead, fitness-related differences between the sexes are potentially sufficient to explain many natural patterns in immunocompetence.

  • 37.
    Nussbaum, Thomas
    et al.
    Institute of Zoophysiology, University of Bonn, Germany.
    Dircksen, Heinrich
    Institute of Zoophysiology, University of Bonn, Germany.
    Neuronal pathways of classical crustacean neurohormones in the central nervous system of the woodlouse, Oniscus asellus (L.)1995Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 347, nr 1320, s. 139-154Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Neuropeptide-immunoreactive neurons have been mapped by immunocytochemistry in whole-mount preparations and sections of the central nervous system of Oniscus asellus. We tested rabbit antisera against decapod crustacean hyperglycemic hormone (CHH), moult inhibiting hormone (MIH), pigment dispersing hormone (PDH) and red pigment concentrating hormone (RPCH). Four CHH- and three PDH-immunoreactive neurons localized in the superior median protocerebrum of the brain constitute neurosecretory pathways to the neurohaemal sinus gland. No immunoreactive structures have been detected with an antiserum against MIH of Carcinus maenus. Another, newly identified neurosecretory pathway is formed by a group of RPCH-immunoreactive neurons in the mandibular ganglion. These neurons project to the neurohaemal lateral cephalic nerve plexus. Further PDH- and RPCH-immunoreactive neurons and fibres occur in the brain and the ventral nerve cord (VNC). Two groups of PDH-immunoreactive neurons supply brain and optic lobe neuropils, the bases of the ommatidia, and probably give rise to descending fibres innervating all VNC-neuropils. Two groups and five individuals of RPCH-immunoreactive neurons that innervate several brain neuropils or occur as ascending neurons in the VNC have been reconstructed. The CHH-immunoreactive neurons, and distinct types of PDH- and RPCH-immunoreactive neurons obviously belong to classical hormone-producing neurosecretory pathways. At least the CHH-immunoreactive cells seem to be part of an isopod homologue of the decapod X-organ. The existence of other PDH- and RPCH-immunoreactive interneurons suggests additional functions of these peptides as neurotransmitters or neuromodulators, which is in agreement with similar observations in the decapod central nervous system.

  • 38. Oleszkiewicz, A.
    et al.
    Kunkel, F.
    Larsson, Maria
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen, Perception och psykofysik.
    Hummel, T.
    Consequences of undetected olfactory loss for human chemosensory communication and well-being2020Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 375, nr 1800, artikel-id 20190265Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Olfactory perception has implications for human chemosensory communication and in a broader context, it affects well-being. However, most of the studies investigating the consequences of olfactory loss have recruited patients who have already been categorized as having a dysfunctional sense of smell and sought help in an ENT clinic. We revisit these findings by distinguishing subjects with olfactory impairment from a group of subjects who all declared a normal sense of smell when enrolling for this study. In the initial sample of 203 individuals, we found 59 to have impaired olfaction and four with marginal olfactory performance, not useful in daily life. Interestingly, we found a significant between-group difference in cognitive functioning, further supporting the notion of the relationship between cognition and olfactory performance. However, their chemosensory communication and well-being appeared not to be different from subjects with normosmia. Impaired olfactory function certainly has a severe impact on daily life but more so in individuals who are bothered with it and decide to seek treatment. The limited-to-no olfactory perception in the fraction of subjects who neither complain about it nor seek help in ENT clinics does not seem to have a major effect on their social, cognitive, emotional and health functioning. This article is part of the Theo Murphy meeting issue 'Olfactory communication in humans'.

  • 39. Rendell, L.
    et al.
    Boyd, R.
    Enquist, Magnus
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Feldman, M. W.
    Fogarty, L.
    Laland, K. N.
    How copying affects the amount, evenness and persistence of cultural knowledge: insights from the social learning strategies tournament2011Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 366, nr 1567, s. 1118-1128Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Darwinian processes should favour those individuals that deploy the most effective strategies for acquiring information about their environment. We organized a computer-based tournament to investigate which learning strategies would perform well in a changing environment. The most successful strategies relied almost exclusively on social learning (here, learning a behaviour performed by another individual) rather than asocial learning, even when environments were changing rapidly; moreover, successful strategies focused learning effort on periods of environmental change. Here, we use data from tournament simulations to examine how these strategies might affect cultural evolution, as reflected in the amount of culture (i.e. number of cultural traits) in the population, the distribution of cultural traits across individuals, and their persistence through time. We found that high levels of social learning are associated with a larger amount of more persistent knowledge, but a smaller amount of less persistent expressed behaviour, as well as more uneven distributions of behaviour, as individuals concentrated on exploiting a smaller subset of behaviour patterns. Increased rates of environmental change generated increases in the amount and evenness of behaviour. These observations suggest that copying confers on cultural populations an adaptive plasticity, allowing them to respond to changing environments rapidly by drawing on a wider knowledge base.

  • 40. Rinne, J.
    et al.
    Tuovinen, J.-P.
    Klemedtsson, L.
    Aurela, M.
    Holst, J.
    Lohila, A.
    Weslien, P.
    Vestin, P.
    Łakomiec, P.
    Peichl, M.
    Tuittila, E.-S.
    Heiskanen, L.
    Laurila, T.
    Li, X.
    Alekseychik, P.
    Mammarella, I.
    Ström, L.
    Crill, Patrick
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologiska vetenskaper.
    Nilsson, M. B.
    Effect of the 2018 European drought on methane and carbon dioxide exchange of northern mire ecosystems2020Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 375, nr 1810, artikel-id 20190517Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We analysed the effect of the 2018 European drought on greenhouse gas (GHG) exchange of five North European mire ecosystems. The low precipitation and high summer temperatures in Fennoscandia led to a lowered water table in the majority of these mires. This lowered both carbon dioxide (CO2) uptake and methane (CH4) emission during 2018, turning three out of the five mires from CO(2)sinks to sources. The calculated radiative forcing showed that the drought-induced changes in GHG fluxes first resulted in a cooling effect lasting 15-50 years, due to the lowered CH(4)emission, which was followed by warming due to the lower CO(2)uptake. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'.

  • 41.
    Rocha, Juan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Yletyinen, Johanna
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Biggs, Reinette
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. Stellenbosch University, South Africa.
    Blenckner, Thorsten
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Peterson, Garry
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Marine regime shifts: drivers and impacts on ecosystems services2015Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, nr 1659, artikel-id 20130273Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Marine ecosystems can experience regime shifts, in which they shift from being organized around one set of mutually reinforcing structures and processes to another. Anthropogenic global change has broadly increased a wide variety of processes that can drive regime shifts. To assess the vulnerability of marine ecosystems to such shifts and their potential consequences, we reviewed the scientific literature for 13 types of marine regime shifts and used networks to conduct an analysis of co-occurrence of drivers and ecosystem service impacts. We found that regime shifts are caused by multiple drivers and have multiple consequences that co-occur in a non-random pattern. Drivers related to food production, climate change and coastal development are the most common co-occurring causes of regime shifts, while cultural services, biodiversity and primary production are the most common cluster of ecosystem services affected. These clusters prioritize sets of drivers for management and highlight the need for coordinated actions across multiple drivers and scales to reduce the risk of marine regime shifts. Managerial strategies are likely to fail if they only address well-understood or data-rich variables, and international cooperation and polycentric institutions will be critical to implement and coordinate action across the scales at which different drivers operate. By better understanding these underlying patterns, we hope to inform the development of managerial strategies to reduce the risk of high-impact marine regime shifts, especially for areas of the world where data are not available or monitoring programmes are not in place.

  • 42. Romano, A.
    et al.
    Giardini, F.
    Columbus, S.
    de Kwaadsteniet, E. W.
    Kisfalusi, D.
    Triki, Zegni
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Neuchâtel, Switzerland.
    Snijders, C.
    Hagel, K.
    Reputation and socio-ecology in humans2021Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 376, nr 1838, artikel-id 20200295Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Reputation is a fundamental feature of human sociality as it sustains cooperative relationships among unrelated individuals. Research from various disciplines provides insights on how individuals form impressions of others, condition their behaviours based on the reputation of their interacting partners and spread or learn such reputations. However, past research has often neglected the socio-ecological conditions that can shape reputation systems and their effect on cooperation. Here, we outline how social environments, cultural values and institutions come to play a crucial role in how people navigate reputation systems. Moreover, we illustrate how these socio-ecological dimensions affect the interdependence underlying social interactions (e.g. potential recipients of reputational benefits, degree of dependence) and the extent to which reputation systems promote cooperation. To do so, we review the interdisciplinary literature that illustrates how reputation systems are shaped by the variation of prominent ecological features. Finally, we discuss the implications of a socio-ecological approach to the study of reputation and outline potential avenues for future research.

  • 43. Rosani, Umberto
    et al.
    Bortoletto, Enrico
    Bai, Chang-Ming
    Novoa, Beatriz
    Figueras, Antonio
    Venier, Paola
    Fromm, Bastian
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för molekylär biovetenskap, Wenner-Grens institut.
    Digging into bivalve miRNAomes: between conservation and innovation2021Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 376, nr 1825, artikel-id 20200165Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Bivalves are a diverse mollusc group of economic and ecological importance. An evident resilience to pollution, parasites and extreme environments makes some bivalve species important models for studying adaptation and immunity. Despite substantial progress in sequencing projects of bivalves, information on non-coding genes and gene-regulatory aspects is still lacking. Here, we review the current repertoire of bivalve microRNAs (miRNAs), important regulators of gene expression in Metazoa. We exploited available short non-coding RNA (sncRNA) data for Pinctada martensii, Crassostrea gigas, Corbicula fluminea, Tegillarca granosa and Ruditapes philippinarum, and we produced new sncRNA data for two additional bivalves, the Mediterranean mussel Mytilus galloprovincialis and the blood clam Scapharca broughtonii. We found substantial heterogeneity and incorrect annotations of miRNAs; hence, we reannotated conserved miRNA families using recently established criteria for bona fide microRNA annotation. We found 106 miRNA families missing in the previously published bivalve datasets and 89 and 87 miRNA complements were identified in the two additional species. The overall results provide a homogeneous and evolutionarily consistent picture of miRNAs in bivalves and enable future comparative studies. The identification of two bivalve-specific miRNA families sheds further light on the complexity of transcription and its regulation in bivalve molluscs.

    This article is part of the Theo Murphy meeting issue ‘Molluscan genomics: broad insights and future directions for a neglected phylum’.

  • 44. Sarolidou, Georgia
    et al.
    Axelsson, John
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Kimball, Bruce A.
    Sundelin, Tina
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Regenbogen, Christina
    Lundström, Johan N.
    Stockholms universitet, Humanistiska fakulteten, Institutionen för lingvistik. Karolinska Institutet, Sweden; University of Pennsylvania, USA; Monell Chemical Senses Center, USA.
    Lekander, Mats
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet. Karolinska Institutet, Sweden.
    Olsson, Mats J.
    People expressing olfactory and visual cues of disease are less liked2020Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 375, nr 1800, artikel-id 20190272Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For humans, like other social animals, behaviour acts as a first line of defence against pathogens. A key component is the ability to detect subtle perceptual cues of sick conspecifics. The present study assessed the effects of endotoxin-induced olfactory and visual sickness cues on liking, as well as potential involved mechanisms. Seventy-seven participants were exposed to sick and healthy facial pictures and body odours from the same individual in a 2 x 2 factorial design while disgust-related facial electromyography (EMG) was recorded. Following exposure, participants rated their liking of the person presented. In another session, participants also answered questionnaires on perceived vulnerability to disease, disgust sensitivity and health anxiety. Lower ratings of liking were linked to both facial and body odour disease cues as main effects. Disgust, as measured by EMG, did not seem to be the mediating mechanism, but participants who perceived themselves as more prone to disgust, and as more vulnerable to disease, liked presented persons less irrespectively of their health status. Concluding, olfactory and visual sickness cues that appear already a few hours after the experimental induction of systemic inflammation have implications for human sociality and may as such be a part of a behavioural defence against disease. This article is part of the Theo Murphy meeting issue 'Olfactory communication in humans'.

  • 45.
    Schönenberger, Jürg
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    von Balthazar, Maria
    Sytsma, Kenneth J.
    Diversity and evolution of floral structure among early diverging lineages in the Ericales2010Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 365, nr 1539, s. 437-448Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This is a combination of review and original data on floral structure and diversity in the two earliest diverging lineages of the Ericales, i.e. the balsaminoids, comprising Balsaminaceae, Marcgraviaceae and Tetrameristaceae, and the polemonioids, comprising Fouquieriaceae and Polemoniaceae. Each clade is strongly supported in molecular studies, while structural synapomorphies have largely been lacking. For the balsaminoid families, we compare floral morphology, anatomy and histology among selected taxa and find that the entire clade is strongly supported by the shared presence of nectariferous tissue in the floral periphery, thread-like structures on anthers, truncate stigmas, secretion in the ovary, as well as mucilage cells, raphides and tannins in floral tissues. A possible sister group relationship between Balsaminaceae and Tetrameristaceae is supported by the shared presence of post-genital fusion of filaments and ovary and a star-shaped stylar canal. For polemonioids, we document unexpected diversity of floral features in Polemoniaceae, partly providing structural links to Fouquieriaceae. Features include cochlear and quincuncial corolla aestivation, connective protrusions, ventrifixed anthers and nectariferous tissue in the base of the ovary. In addition, we outline future directions for research on floral structure in the Ericales and briefly discuss the general importance of structural studies for our understanding of plant phylogeny and evolution.

  • 46. Smolla, Marco
    et al.
    Jansson, Fredrik
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur, Centrum för evolutionär kulturforskning. Mälardalen University, Sweden.
    Lehmann, Laurent
    Houkes, Wybo
    Weissing, Franz J.
    Hammerstein, Peter
    Dall, Sasha R. X.
    Kuijper, Bram
    Enquist, Magnus
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur, Centrum för evolutionär kulturforskning. Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Underappreciated features of cultural evolution2021Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 376, nr 1828, artikel-id 20200259Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Cultural evolution theory has long been inspired by evolutionary biology. Conceptual analogies between biological and cultural evolution have led to the adoption of a range of formal theoretical approaches from population dynamics and genetics. However, this has resulted in a research programme with a strong focus on cultural transmission. Here, we contrast biological with cultural evolution, and highlight aspects of cultural evolution that have not received sufficient attention previously. We outline possible implications for evolutionary dynamics and argue that not taking them into account will limit our understanding of cultural systems. We propose 12 key questions for future research, among which are calls to improve our understanding of the combinatorial properties of cultural innovation, and the role of development and life history in cultural dynamics. Finally, we discuss how this vibrant research field can make progress by embracing its multidisciplinary nature. This article is part of the theme issue 'Foundations of cultural evolution'.

  • 47.
    Stajic, Dragan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Jansen, Lars E. T.
    Empirical evidence for epigenetic inheritance driving evolutionary adaptation2021Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 376, nr 1826, artikel-id 20200121Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The cellular machinery that regulates gene expression can be self-propagated across cell division cycles and even generations. This renders gene expression states and their associated phenotypes heritable, independently of genetic changes. These phenotypic states, in turn, can be subject to selection and may influence evolutionary adaptation. In this review, we will discuss the molecular basis of epigenetic inheritance, the extent of its transmission and mechanisms of evolutionary adaptation. The current work shows that heritable gene expression can facilitate the process of adaptation through the increase of survival in a novel environment and by enlarging the size of beneficial mutational targets. Moreover, epigenetic control of gene expression enables stochastic switching between different phenotypes in populations that can potentially facilitate adaptation in rapidly fluctuating environments. Ecological studies of the variation of epigenetic markers (e.g. DNA methylation patterns) in wild populations show a potential contribution of this mode of inheritance to local adaptation in nature. However, the extent of the adaptive contribution of the naturally occurring variation in epi-alleles compared to genetic variation remains unclear.

    This article is part of the theme issue ‘How does epigenetics influence the course of evolution?’

  • 48. Stevens, Martin
    et al.
    Merilaita, Sami
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Animal camouflage: current issues and new perspectives2009Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, nr 1516, s. 423-427Artikel i tidskrift (Refereegranskat)
  • 49. Stevens, Martin
    et al.
    Merilaita, Sami
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Defining disruptive coloration and distinguishing its functions2009Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, s. 481-488Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Disruptive coloration breaks up the shape and destroys the outline of an object, hindering detection. The principle was first suggested approximately a century ago, but, although research has significantly increased, the field remains conceptually unstructured and no unambiguous definition exists. This has resulted in variable use of the term, making it difficult to formulate testable hypotheses that are comparable between studies, slowing down advancement in this field. Related to this, a range of studies do not effectively distinguish between disruption and other forms of camouflage. Here, we give a formal definition of disruptive coloration, reorganize a range of sub-principles involved in camouflage and argue that five in particular are specifically related to disruption: differential blending; maximum disruptive contrast; disruption of surface through false edges; disruptive marginal patterns; and coincident disruptive coloration. We discuss how disruptive coloration can be optimized, how it can relate to other forms of camouflage markings and where future work is particularly needed.

  • 50.
    Stobbe, Nina
    et al.
    University of Freiburg, Department of Evolutionary Biology and Animal Ecology.
    Dimitrova, Marina
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för zoologisk ekologi. Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Merilaita, Sami
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för zoologisk ekologi. Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Schaefer, H. Martin
    University of Freiburg, Department of Evolutionary Biology and Animal Ecology.
    Chromaticity in the UV/blue range facilitates the search for achromatically background-matching prey in birds2009Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, nr 1516, s. 511-517Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A large variety of predatory species rely on their visual abilities to locate their prey. However, thesearch for prey may be hampered by prey camouflage. The most prominent example of concealingcoloration is background-matching prey coloration characterized by a strong visual resemblance ofprey to the background. Even though this principle of camouflage was recognized to efficiently workin predator avoidance a long time ago, the underlying mechanisms are not very well known. In thisstudy, we assessed whether blue tits (Cyanistes caeruleus) use chromatic cues in the search for prey.Weused two prey types that were achromatically identical but differed in chromatic properties in theUV/blue range and presented them on two achromatically identical backgrounds. The backgroundshad either the same chromatic properties as the prey items (matching combination) or differed intheir chromatic properties (mismatching combination). Our results show that birds use chromaticcues in the search for mismatching prey, whereupon chromatic contrast leads to a ‘pop-out’ of theprey item from the background. When prey was presented on a matching background, search timeswere significantly higher. Interestingly, search for more chromatic prey on the matching backgroundwas easier than search for less chromatic prey on the matching background. Our results indicate thatbirds use both achromatic and chromatic cues when searching for prey, and that the combination ofboth cues might be helpful in the search task.

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