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  • 1. Beaugrand, G.
    et al.
    Conversi, A.
    Chiba, S.
    Edwards, M.
    Fonda-Umani, S.
    Greene, C.
    Mantua, N.
    Otto, Saskia A.
    Stockholm University, Faculty of Science, 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 Hemisphere2015In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, no 1659, article id 20130272Article in journal (Refereed)
    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.

  • 2. Callaghan, Terry V.
    et al.
    Jonasson, Christer
    Thierfelder, Tomas
    Yang, Zhenlin
    Hedenås, Henrik
    Johansson, Margareta
    Molau, Ulf
    Stockholm University, Faculty of Science, 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 drivers2013In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 368, no 1624Article in journal (Refereed)
    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.

  • 3. 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
    Stockholm University, Faculty of Science, Department of Zoology.
    Buechel, Severine D.
    Stockholm University, Faculty of Science, Department of Zoology.
    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-analysis2018In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 373, no 1756, article id 20170281Article in journal (Refereed)
    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'.

  • 4. Conversi, Alessandra
    et al.
    Dakos, Vasilis
    Gårdmark, Anna
    Ling, Scott
    Folke, Carl
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. Royal Swedish Academy of Sciences, Sweden.
    Mumby, Peter J.
    Greene, Charles
    Edwards, Martin
    Blenckner, Thorsten
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Casini, Michele
    Pershing, Andrew
    Möllmann, Christian
    A holistic view of marine regime shifts2015In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, no 1659, article id 20130279Article, review/survey (Refereed)
    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.

  • 5.
    Enquist, Magnus
    et al.
    Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution. Stockholm University, Faculty of Science, Department of Zoology.
    Ghirlanda, Stefano
    Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution.
    Eriksson, Kimmo
    Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution.
    Modelling the evolution and diversity of cumulative culture2011In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 366, no 1563, p. 412-423Article in journal (Refereed)
    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).

  • 6.
    Faye, Ingrid
    et al.
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Lindberg, Bo G.
    Towards a paradigm shift in innate immunity-seminal work by Hans G. Boman and co-workers2016In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 371, no 1695, article id 20150303Article, review/survey (Refereed)
    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'.

  • 7.
    Ghirlanda, Stefano
    et al.
    Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution.
    Frasnelli, Elisa
    Vallortigara, Giorgio
    Intraspecific competition and coordination in the evolution of lateralization2009In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, no 1519, p. 861-866Article in journal (Refereed)
    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.

  • 8.
    Höök, Kristina
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Affective loop experiences: designing for interactional embodiment2009In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, no 1535, p. 3585-3595Article in journal (Refereed)
    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.

  • 9. Jickells, T.
    et al.
    Baker, A. R.
    Cape, J. N.
    Cornell, Sarah
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Nemitz, E.
    The cycling of organic nitrogen through the atmosphere2013In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 368, no 1621Article, review/survey (Refereed)
    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.

  • 10.
    Jouffray, Jean-Baptiste
    et al.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. Royal Swedish Academy of Sciences, Sweden.
    Nyström, Magnus
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Norström, Albert V.
    Stockholm University, Faculty of Science, 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 archipelago2015In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, no 1659, article id 20130268Article in journal (Refereed)
    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.

  • 11. Krams, Indrikis
    et al.
    Krama, Tatjana
    Freeberg, Todd M.
    Kullberg, Cecilia
    Stockholm University, Faculty of Science, Department of Zoology.
    Lucas, Jeffrey R.
    Linking social complexity and vocal complexity: a parid perspective2012In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 367, no 1597, p. 1879-1891Article, review/survey (Refereed)
    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.

  • 12. Krause, J.
    et al.
    Herbert-Read, James E.
    Stockholm University, Faculty of Science, Department of Zoology. Uppsala University, Sweden.
    Seebacher, F.
    Domenici, P.
    Wilson, Alexander D. M.
    Stockholm University, Faculty of Science, Department of Zoology. 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 fish2017In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 372, no 1727, article id 20160232Article in journal (Refereed)
    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'.

  • 13.
    Krzewińska, Maja
    et al.
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Archaeological Research Laboratory. University of Oslo, Norway.
    Bjørnstad, Gro
    Skoglund, Pontus
    Olason, Pall Isolfur
    Bill, Jan
    Götherström, Anders
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Archaeological Research Laboratory. Uppsala University, Sweden.
    Hagelberg, Erika
    Mitochondrial DNA variation in the Viking age population of Norway2015In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, no 1660Article in journal (Refereed)
    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.

  • 14.
    Lansing, J. Stephen
    et al.
    Stockholm University, Stockholm Resilience Centre.
    Fox, Karyn M.
    Niche construction on Bali: the gods of the countryside2011In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 366, no 1566, p. 927-34Article in journal (Refereed)
    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.

  • 15. Malmström, Helena
    et al.
    Linderholm, Anna
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies. Durham University, UK.
    Skoglund, Pontus
    Storå, Jan
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies.
    Sjödin, Per
    Gilbert, M. Thomas P.
    Holmlund, Gunilla
    Willerslev, Eske
    Jakobsson, Mattias
    Lidén, Kerstin
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies.
    Götherstrom, Anders
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies. Uppsala University, Sweden.
    Ancient mitochondrial DNA from the northern fringe of the Neolithic farming expansion in Europe sheds light on the dispersion process2015In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, no 1660, article id 20130373Article in journal (Refereed)
    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.

  • 16. Mendez, Derek
    et al.
    Lane, Thomas J.
    Sung, Jongmin
    Sellberg, Jonas
    Stockholm University, Faculty of Science, Department of Physics. 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 resolution2014In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 369, no 1647, p. 20130315-Article in journal (Refereed)
    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.

  • 17. Nunn, Charles L
    et al.
    Lindenfors, Patrik
    Stockholm University, Faculty of Science, Department of Zoology. Stockholm University, Faculty of Humanities, Centre for Cultural Evolution.
    Pursall, E. Rhiannon
    Rolff, Jens
    On sexual dimorphism in immune function2009In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, no 1513, p. 61-69Article in journal (Refereed)
    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.

  • 18.
    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.)1995In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 347, no 1320, p. 139-154Article in journal (Refereed)
    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.

  • 19. Rendell, L.
    et al.
    Boyd, R.
    Enquist, Magnus
    Stockholm University, Faculty of Science, Department of Zoology.
    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 tournament2011In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 366, no 1567, p. 1118-1128Article in journal (Refereed)
    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.

  • 20.
    Rocha, Juan
    et al.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Yletyinen, Johanna
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Biggs, Reinette
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. Stellenbosch University, South Africa.
    Blenckner, Thorsten
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Peterson, Garry
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Marine regime shifts: drivers and impacts on ecosystems services2015In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, no 1659, article id 20130273Article in journal (Refereed)
    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.

  • 21.
    Schönenberger, Jürg
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    von Balthazar, Maria
    Sytsma, Kenneth J.
    Diversity and evolution of floral structure among early diverging lineages in the Ericales2010In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 365, no 1539, p. 437-448Article in journal (Refereed)
    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.

  • 22. Stevens, Martin
    et al.
    Merilaita, Sami
    Stockholm University, Faculty of Science, Department of Zoology.
    Animal camouflage: current issues and new perspectives2009In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, no 1516, p. 423-427Article in journal (Refereed)
  • 23. Stevens, Martin
    et al.
    Merilaita, Sami
    Stockholm University, Faculty of Science, Department of Zoology.
    Defining disruptive coloration and distinguishing its functions2009In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, p. 481-488Article in journal (Refereed)
    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.

  • 24.
    Stobbe, Nina
    et al.
    University of Freiburg, Department of Evolutionary Biology and Animal Ecology.
    Dimitrova, Marina
    Stockholm University, Faculty of Science, Department of Zoology, Department of Animal Ecology. Stockholm University, Faculty of Science, Department of Zoology.
    Merilaita, Sami
    Stockholm University, Faculty of Science, Department of Zoology, Department of Animal Ecology. Stockholm University, Faculty of Science, Department of Zoology.
    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 birds2009In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 364, no 1516, p. 511-517Article in journal (Refereed)
    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.

  • 25. Sumpter, David J. T.
    et al.
    Szorkovszky, Alex
    Kotrschal, Alexander
    Stockholm University, Faculty of Science, Department of Zoology.
    Kolm, Niclas
    Stockholm University, Faculty of Science, Department of Zoology.
    Herbert-Read, James E.
    Stockholm University, Faculty of Science, Department of Zoology.
    Using activity and sociability to characterize collective motion2018In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 373, no 1746, article id 20170015Article, review/survey (Refereed)
    Abstract [en]

    A wide range of measurements can be made on the collective motion of groups, and the movement of individuals within them. These include, but are not limited to: group size, polarization, speed, turning speed, speed or directional correlations, and distances to near neighbours. From an ecological and evolutionary perspective, we would like to know which of these measurements capture biologically meaningful aspects of an animal's behaviour and contribute to its survival chances. Previous simulation studies have emphasized two main factors shaping individuals' behaviour in groups; attraction and alignment. Alignment responses appear to be important in transferring information between group members and providing synergistic benefits to group members. Likewise, attraction to conspecifics is thought to provide benefits through, for example, selfish herding. Here, we use a factor analysis on a wide range of simple measurements to identify two main axes of collective motion in guppies (Poecilia reticulata): (i) sociability, which corresponds to attraction (and to a lesser degree alignment) to neighbours, and (ii) activity, which combines alignment with directed movement. We show that for guppies, predation in a natural environment produces higher degrees of sociability and (in females) lower degrees of activity, while female guppies sorted for higher degrees of collective alignment have higher degrees of both sociability and activity. We suggest that the activity and sociability axes provide a useful framework for measuring the behaviour of animals in groups, allowing the comparison of individual and collective behaviours within and between species.

  • 26.
    Uggla, Caroline
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Sociology. University College London, UK.
    Mace, Ruth
    Adult sex ratio and social status predict mating and parenting strategies in Northern Ireland2017In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 372, no 1729, article id 20160318Article in journal (Refereed)
    Abstract [en]

    Evidence from animal species indicates that a male-biased adult sex ratio (ASR) can lead to higher levels of male parental investment and that there is heterogeneity in behavioural responses to mate scarcity depending on mate value. In humans, however, there is little consistent evidence of the effect of the ASR on pair-bond stability and parental investment and even less of how it varies by an individual's mate value. In this paper we use detailed census data from Northern Ireland to test the association between the ASR and pair-bond stability and parental investment by social status ( education and social class) as a proxy for mate value. We find evidence that female, but not male, cohabitation is associated with the ASR. In female-biased areas women with low education are less likely to be in a stable pair-bond than highly educated women, but in male-biased areas women with the lowest education are as likely to be in a stable pair-bond as their most highly educated peers. For both sexes risk of separation is greater at female-biased sex ratios. Lastly, our data show a weak relationship between parental investment and the ASR that depends on social class. We discuss these results in the light of recent reformulations of parental investment theory. This article is part of the themed issue `Adult sex ratios and reproductive decisions: a critical re-examination of sex differences in human and animal societies'.

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