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[Aim] One of the main goals of functional biogeography is to examine distribution patterns of trait diversity, and islands provide excellent study cases for this emerging field. We tested the hypothesis that multiple dispersals from a common mainland pool would promote functional similarity among island systems when environmental conditions are similar, but also novel phenotypic traits related to colonization history and exploitation of new habitats., [Location] Mediterranean Basin and Macaronesian islands., [Taxon] Wolfbane (Periploca laevigata), [Methods] We used the well‐known biogeographical history of a woody plant complex (P. laevigata s.l.) to examine trait variation and how it relates to climatic conditions of mainland and subtropical island settings. In a common garden experiment, we measured a suite of leaf physiological and anatomical traits tightly related to plant performance in 320 seedlings representing 21 populations of five sublineages—the oldest (2.6 my) island colonization (western Canary Islands) as a reference, three sublineages stemming from independent events of island colonization in the last 0.5 my from NW Africa (Cape Verde, Fuerteventura, Lanzarote) and their widespread Mediterranean mainland counterpart., [Results] We observed strong phenotypic divergence between island and mainland sublineages linked to contrasting climatic conditions. Mediterranean mainland populations displayed a very specialized leaf phenotype characteristic of arid plants (i.e. small leaves, amphistomaty, isobilateral mesophyll, high photosynthetic rates). In turn, low seasonality on islands was linked to the recurrent expression of a phenotype characterized by larger leaves and lower photosynthetic rates. Our analyses showed that the high investment in secondary compounds (i.e. tannins) on islands decouples photosynthesis from growth rates. Despite this pattern of parallel differentiation, each island sublineage displayed a distinctive phenotype, with some traits related to colonization time, which resulted in a mosaic of functional variation across island systems., [Main conclusions] Our data suggest that the studied subtropical islands promote expression of traits specific to certain sublineages and other common traits that are no longer adaptive in the original mainland pool due to Pleistocene climatic shifts. These findings ultimately extend the role of islands as biodiversity refugia and hotspots of plant functional diversity.

[Background and Aims] Archipelagos provide a valuable framework for investigating phenotypic evolution under different levels of geographical isolation. Here, we analysed two co-distributed, widespread plant lineages to examine if incipient island differentiation follows parallel patterns of variation in traits related to dispersal and colonization., [Methods] Twenty-one populations of two anemochorous Canarian endemics, Kleinia neriifolia and Periploca laevigata, were sampled to represent mainland congeners and two contrasting exposures across all the main islands. Leaf size, seed size and dispersability (estimated as diaspore terminal velocity) were characterized in each population. For comparison, dispersability was also measured in four additional anemochorous island species. Plastid DNA data were used to infer genetic structure and to reconstruct the phylogeographical pattern of our focal species., [Key Results] In both lineages, mainland-island phenotypic divergence probably started within a similar time frame (i.e. Plio-Pleistocene). Island colonization implied parallel increases in leaf size and dispersability, but seed size showed opposite patterns of variation between Kleinia and Periploca species pairs. Furthermore, dispersability in our focal species was low when compared with other island plants, mostly due to large diaspore sizes. At the archipelago scale, island exposure explained a significant variation in leaf size across islands, but not in dispersability or seed size. Combined analyses of genetic and phenotypic data revealed two consistent patterns: (1) extensive within-island but very limited among-island dispersal, and (2) recurrent phenotypic differentiation between older (central) and younger (peripheral) island populations., [Conclusions] Leaf size follows a more predictable pattern than dispersability, which is affected by stochastic shifts in seed size. Increased dispersability is associated with high population connectivity at the island scale, but does not preclude allopatric divergence among islands. In sum, phenotypic convergent patterns between species suggest a major role of selection, but deviating traits also indicate the potential contribution of random processes, particularly on peripheral islands.

[Premise of the Study] We tested a hypothesis that predicts loss of chemical defenses on island plant populations (LCDIH) as an evolutionary response to limited herbivore pressures., [Methods] Using a common garden approach, we grew 16 populations (N = 286 seedlings) of Periploca laevigata, a Mediterranean shrub for which previous studies suggested that animal browsing elicits defensive responses mediated by tannins. Our experimental setting represented a wide latitudinal gradient (37–15°N) encompassing three island systems, virtually free of large herbivores, and three mainland areas. Putative chemical defenses were estimated from tannin–protein precipitation assays, and inducible responses in growth and chemical traits were assessed between seasons and by subjecting plants to a pruning treatment., [Key Results] We failed to find support for the LCDIH, since island populations (Canary Islands, Cape Verde) had increasingly higher constitutive levels of tannins at lower latitudes. Seasonality, but not experimental pruning, induced variation in levels of tannins in a consistent pattern across populations. Thus, net differences in leaf tannin concentration remained similar among geographical areas regardless of the factor considered, with latitude being the best explanatory factor for this trait over seasonal growth patterns., [Conclusions] Geographical variation in total tannin pools appears to be mediated by factors other than herbivore pressure in P. laevigata. We hypothesize that abiotic correlates of latitude not considered in our study have promoted high constitutive levels of leaf tannins across Macaronesian populations, which ultimately may explain the pattern of seasonal variation and latitudinal increase from Mediterranean to subtropical Cape Verde populations.

Sedimentation of particles in the ocean leads to inhomogeneous horizontal distributions at depth, even if the release process is homogeneous. We study this phenomenon considering a horizontal sheet of sinking particles immersed in an oceanic flow and determine how the particles are distributed when they sediment on the seabed (or are collected at a given depth). The study is performed from a Lagrangian viewpoint attending to the properties of the oceanic flow and the physical characteristics (size and density) of typical biogenic sinking particles. Two main processes determine the distribution, the stretching of the sheet caused by the flow, and its projection on the surface where particles accumulate. These mechanisms are checked, besides an analysis of their relative importance to produce inhomogeneities, with numerical experiments in the Benguela region. Faster (heavier or larger) sinking particles distribute more homogeneously than slower ones.

In an incompressible flow, fluid density remains invariant along fluid element trajectories. This implies that the spatial distribution of non-interacting noninertial particles in such flows cannot develop density inhomogeneities beyond those that are already introduced in the initial condition. However, in certain practical situations, density is measured or accumulated on (hyper-) surfaces of dimensionality lower than the full dimensionality of the flow in which the particles move. An example is the observation of particle distributions sedimented on the floor of the ocean. In such cases, even if the initial distribution of noninertial particles is uniform but its support is finite, advection in an incompressible flow will give rise to inhomogeneities in the observed density. In this paper, we analytically derive, in the framework of an initially homogeneous particle sheet sedimenting toward a bottom surface, the relationship between the geometry of the flow and the emerging distribution. From a physical point of view, we identify the two processes that generate inhomogeneities to be the stretching within the sheet and the projection of the deformed sheet onto the target surface. We point out that an extreme form of inhomogeneity, caustics, can develop for sheets. We exemplify our geometrical results with simulations of particle advection in a simple kinematic flow, study the dependence on various parameters involved, and illustrate that the basic mechanisms work similarly if the initial (homogeneous) distribution occupies a more general region of finite extension rather than a sheet. Sedimentation of small particles in complex flows is an outstanding problem in science and technology. In particular, the sinking of biogenic particles from the marine surface to the bottom is a fundamental process of the biological carbon pump, playing a key role in the global carbon cycle. A complete understanding of this problem is still lacking. It has been recently shown that de

Marine resources stewardships are progressively becoming more receptive to an effective incorporation of both ecosystem and environmental complexities into the analytical frameworks of fisheries assessment. Understanding and predicting marine fish production for spatially and demographically complex populations in changing environmental conditions is however still a difficult task. Indeed, fisheries assessment is mostly based on deterministic models that lack realistic parameterizations of the intricate biological and physical processes shaping recruitment, a cornerstone in population dynamics. We use here a large metapopulation of a harvested fish, the European hake (Merluccius merluccius), managed across transnational boundaries in the northwestern Mediterranean, to model fish recruitment dynamics in terms of physics‐dependent drivers related to dispersal and survival. The connectivity among nearby subpopulations is evaluated by simulating multi‐annual Lagrangian indices of larval retention, imports, and self‐recruitment. Along with a proxy of the regional hydroclimate influencing early life stages survival, we then statistically determine the relative contribution of dispersal and hydroclimate for recruitment across contiguous management units. We show that inter‐annual variability of recruitment is well reproduced by hydroclimatic influences and synthetic connectivity estimates. Self‐recruitment (i.e., the ratio of retained locally produced larvae to the total number of incoming larvae) is the most powerful metric as it integrates the roles of retained local recruits and immigrants from surrounding subpopulations and is able to capture circulation patterns affecting recruitment at the scale of management units. We also reveal that the climatic impact on recruitment is spatially structured at regional scale due to contrasting biophysical processes not related to dispersal. Self‐recruitment calculated for each management unit explains between 19% and 32.9% of the

Sedimentation of particles in the ocean leads to inhomogeneous horizontal distributions at depth. The present dataset contains density and trajectory data for particle sedimentation computed from the velocity field given by a ROMS simulation at 1/12 x 1/12 degrees of horizontal resolution in the region of Benguela (south east Atlantic). Direct particle sampling as well as the result of a geometrical approach are included.

Lagrangian Flow Network (LFN) is a modelling framework in which ocean sub-areas are represented as nodes in a network interconnected by links representing transport of propagules (eggs and larvae) by currents. We asses the sensitivity and robustness of four LFN-derived connectivity metrics measuring retention and exchange. The most relevant parameters are tested over large ranges and a wide region with contrasting hydrodynamics: density of released particles, node size (spatial scale of discretization), Pelagic Larval Duration (PLD) and spawning modality. We find a minimum density of released particles that guarantees reliable values for most of the metrics examined. We also find that node size has a nontrivial influence on them. Connectivity estimates for long PLDs are more robust against biological uncertainties (PLD and spawning date) than for short PLDs. For mass-spawners releasing propagules over short periods (≈ 2-10 days), daily release must be simulated to properly consider connectivity fluctuations due to variable currents. In contrast, average connectivity estimates for species that spawn repeatedly over longer durations (few weeks to few months) remain robust even using longer periodicity (5-10 days). Our results have implications to design connectivity experiments with particle-tracking models and to evaluate the reliability of their results.

We study the problem of sinking particles in a realistic oceanic flow, with major energetic structures in the mesoscale, focussing in the range of particle sizes and densities appropriate for marine biogenic particles. Our aim is to unify the theoretical investigations with its applications in the oceanographic context and considering a mesoscale simulation of the oceanic velocity field. By using the equation of motion of small particles in a fluid flow, we assess the influence of physical processes such as the Coriolis force and the inertia of the particles, and we conclude that they represent negligible corrections to the most important terms, which are passive motion with the velocity of the flow, and a constant added vertical velocity due to gravity. Even if within this approximation three-dimensional clustering of particles can not occur, two-dimensional cuts or projections of the evolving three-dimensional density can display inhomogeneities similar to the ones observed in sinking ocean particles.

History has got the monopoly of legitimate representation of the past, above all due to its privileged academic position. Its accounts operate as true and valid and often label all the rest as fiction. There are nevertheless some other forms, linked to memory, capable of learning from and narrating through emotions, opening paths of understanding, compromise and intervention in society. Referred to the memory of repression in Spain, we talk in this article about graphic novel, photography and documentary films., History has got the monopoly of legitimate representation of the past, above all due to its privileged academic position. Its accounts operate as true and valid and often label all the rest as fiction. There are nevertheless some other forms, linked to memory, capable of learning from and narrating through emotions, opening paths of understanding, compromise and intervention in society. Referred to the memory of repression in Spain, we talk in this article about graphic novel, photography and documentary films.

Assessing the spatial structure and dynamics of marine populations, especially considering the various and interlocked scales typical of oceanic systems, is still a major challenge in Ecology. We present a novel framework based on the construction and analysis of Lagrangian Flow Network (LFNs) which results in a systematic characterization of dispersal and connectivity of early life history stages of marine organisms. The network is constructed by subdividing the basin into an ensemble of sub-regions which are interconnected through the transport of propagules by ocean currents. The analysis of such networks allows the identification of hydrodynamical provinces and the computation of connectivity proxies measuring retention and exchange of larvae at multiple scales. Due to our spatial discretization and subsequent network representation, as well as our Lagrangian approach, further methodological improvements are handily accessible. It permits a better characterization of population connectivity and allows improving the management and protection of marine ecosystems.

We revisit the universal behavior of crystalline membranes at and below the crumpling transition, which pertains to the mechanical properties of important soft and hard matter materials, such as the cytoskeleton of red blood cells or graphene. Specifically, we perform large-scale Monte Carlo simulations of a triangulated two-dimensional phantom network which is freely fluctuating in three-dimensional space. We obtain a continuous crumpling transition characterized by critical exponents which we estimate accurately through the use of finite-size techniques. By controlling the scaling corrections, we additionally compute with high accuracy the asymptotic value of the Poisson ratio in the flat phase, thus characterizing the auxetic properties of this class of systems. We obtain agreement with the value which is universally expected for polymerized membranes with a fixed connectivity.