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Wildfire byproducts enter into the oceans via terrestrial and atmospheric routes. They pose a challenge to the sustainability of marine ecosystems, especially under the current increase in fire activity. Research is needed to unravel the dynamics between wildfires and marine life, and the oceans' potential to mitigate wildfire emissions. [ABSTRACT FROM AUTHOR]

Marine protected areas (MPAs) provide multiple conservation benefits, thus raising the question of how good and consistent they are at their roles. Here, we quantified three components, namely, diversity, biomass, and other relevant variables, in numerous protected and unprotected areas across four marine ecoregions in south-western Europe. We created a "global conservation status index" (CSI global) as the sum of CSI diversity , CSI biomass , and CSI relevant. We then tested whether CSI and its three components varied as a function of protection and marine ecoregion. MPA efficiency, defined as the effect size of protection on CSI global , was unreliable and varied with geography. CSI biomass and CSI relevant contributed to the unreliability of MPA efficiency, while CSI diversity was reliable. CSI biomass showed the major efficiency in protected areas (60%). Biomass of threatened species was the single largest variable that contributed to MPA efficiency. Our easy-to-use approach can identify high- and low-efficient MPAs and help to clarify their actual roles. • We develop the Conservation Status Index to test the efficiency of marine protection. • The efficiency of marine protection depends on the ecoregion. • The CSI biomass shows the major efficiency in protected areas. • The biomass of threatened species presents the highest contribution to the efficiency. [ABSTRACT FROM AUTHOR]

Highlights • Classical ecosystem ecology (EE) is rooted in thermodynamics (T). • The concept degrees of freedom (df) is key in T; it should have an equivalent in EE. • The triad biomass-dispersal-diversity is proposed as the main set of ecological df. • Six essential traits that support the previous proposal are explored. • Intra- & inter-disciplinary cases based on field data backing this proposal are shown. Abstract There is a neglected old schism in ecosystem ecology (EE): the foundations of crucial concepts and principles of EE lie in thermodynamics, but the current mainstream of ecological thought is significantly biased towards contingent mathematical models disconnected from physics. Frequently, these models have weak theoretical support in ecology itself, as well as a limited empirical validation. This situation emerged when some ecologists became aware that, seemingly, thermodynamics (devoted to study the dynamics of closed systems in equilibrium) should be useless to understand ecosystems (far-from-equilibrium open systems). The solution was, either developing a sort of "new physics" weakly linked to the principles and methods of conventional physics, or a direction change towards an astonishing diversification of analytical ways. In practice, both things have happened simultaneously. One of the many expressions of this controversial decision was a sort of rigmarole in the use of the concept of "degrees of freedom". This article, based on a recent proposal (organic biophysics of ecosystems, OBEC): (i) contributes to resolve the dilemma physics vs. non-physics in EE; (ii) proposes a plausible and empirically-backed approach to the meaning, interaction and use of the concept of "degrees of freedom" in EE by reducing them to an inseparable triad of indicators (species diversity, dispersal intensity, and fresh biomass or body weight per individual) valid for any kind of ecosystem (non-contingency) and backed by six essential traits (simplicity, universality, evolvability, empirical manageability, inter-model inclusivity, and interdisciplinary scope); and (iii) explores the aftermaths of the aforementioned approach to propose a complementary explanation to the metabolic theory of ecology, as well as the cornerstone of an analytical framework commonly shared by economics and EE, in order to develop a new way of getting reliable results in regard to the interaction between society and nature. In summary, the results included in these three analytical axes (from i to iii) are based on previous publications including empirical field data from 12 different kinds of taxocenes involving a total of 1649 plots and 8.874 × 107 individuals belonging to 1280 species. Besides, this article includes in itself additional data from 638 species of mammals, 97 samples of ruderal vegetation, 26 samples of zooplankton, as well as data in reference to a significant fraction of the U.S.A. population as a whole (x ¯ = 2.973 × 108±8.657 × 106 −S.D.− individuals per year) in combination with abiotic environmental data (mean temperature and emission of greenhouse gases at the country level) over 12 consecutive years. [ABSTRACT FROM AUTHOR]

• There is an analytical gap between species diversity (SDi) and trophodynamics (TD) • A biomass-dispersal trade-off as a function of SDi (bdtSDi) bridges such a gap. • BdtSDi yields an ecological equivalent (k e) of Boltzmann's constant on a global scale. • k e -based calculations provide new indicators for conservation in dynamic multiscapes. • This proposal highlights the link between analytical simplicity and reliability. The spectrum of species diversity (SDi) can be broken down into α SDi (taxocene level), β SDi (community level), and γ SDi (metacommunity level). Species richness (S) and Shannon's index (H) are well-known SDi measures. The use of S as a surrogate for SDi often neglects evenness (J). Additionally, there is a wide variety of indicators of SDi. However, there are no reliable theoretical criteria for selecting the most appropriate SDi index despite the undeniable empirical usefulness of this parameter. This situation is probably due to the analytical gap still existing between SDi and trophodynamics. This article contributes to closing that gap by analyzing why S as a single surrogate for SDi is inconsistent from the trophodynamic point of view, so that an index combining S and J , such as H or H B (Brillouin's index), are the most appropriate choices in the context of a new theoretical framework (organic biophysics of ecosystems, OBEC) based on the well-known classical links between ecosystem ecology and thermodynamics. Exploration of data from reef fish surveys under stationary and non-stationary conditions corroborated the existence of the ecological equivalent of Boltzmann's constant (k eτ (e)) at the worldwide scale. This result substantiates the usefulness of the ecological equivalent of the compressibility factor as an indicator of environmental impact. k eτ (e) stablishes an analytical linkage between ecology, information theory, and statistical mechanics that allowed us to propose a new measure of total negative entropy (a.k.a. syntropy) per survey (S eτT) that is easy to calculate and displayed a highly significant correlation with total standing biomass per survey (m eTs). According to the slope of the regression equation S eτT , m eTs there is a large portion of S eτT that leaks into the environment and/or is captured by numerous ecological degrees of freedom independent of standing biomass. According to the changing value of the exponent of k eτ (e) , even among coexisting taxocenes, it would have been impossible to obtain the results discussed in this article if the analysis had been carried out at the β SDi or γ SDi level. This establishes α SDi as the most appropriate level of analysis to obtain empirically useful results about the key functional connections on which trophodynamic stability depends in dynamic multispaces. The results summarized here are based on the careful selection and intertwining of a few key variables, which indicates the importance of developing models as simple as possible in order to achieve the reliability necessary for successful biological conservation. [ABSTRACT FROM AUTHOR]

Atmospheric deposition of desert dust and other aerosols influence on the open ocean ecosystem and climate. These aerosols provide iron, phosphorus and bio-essential trace elements, which affect the composition and growth of phytoplankton, generating new organic matter that is distributed across the food web. Although this process has an impact on upper trophic levels and fisheries, direct evidence is lacking. Skipjack tropical tuna (Katsuwonus pelamis) is the most important commercial tuna in the Atlantic, main stocks occur in the tropical and subtropical North-East Atlantic. We found that the migrations and fisheries of skipjack are connected to Saharan dust variability. From boreal winter to summer, skipjack performs an Atlantic-Saharan migration, from equatorial (0-5°N) to subtropical waters of the North-East Atlantic (regularly reaching open waters off Mauritania ∼20°N and the Canary Islands ∼28°N), tracking the seasonal shift of dust deposition in the North-East Atlantic. The observed long-term associations of skipjack catch with the seasonal cycles, anomalies and meridional variability of dust over the North-East Atlantic, shows that along the year skipjack catches mainly occur in waters affected by massive dust deposition linked (i) to dust wet deposition in tropical waters and (ii) to dust dry deposition in the Saharan desert-dust outflow. Atmospheric deposition of dust in the open ocean and in upwelling waters contributes to support zooplankton-rich areas, which are optimal for feeding small fish, molluscs and cephalopods, and suitable for feeding large predators, as skipjacks, where they are caught in abundance. The most important fishing area of Atlantic skipjack tuna is located off North West Africa in the waters affected by massive dust deposition that underly the dusty airstream from the North Africa desert. The role of dust as fertilizing and supporter of phytoplankton and zooplankton rich areas also has implications for other species of fishing interest, including other tropical tuna (e.g. bigeye and yellowfin), which are often exploited simultaneously with skipjack by the same fisheries. As far as we know this is the first study showing the connexions between atmospheric inputs of desert dust to ocean and the migrations and fisheries of marine species. These results have important implications on our understanding on the influence of atmospheric dust on marine ecosystems and on the management of fisheries. [Display omitted] • Saharan dust fertilizes the Atlantic Ocean with iron, phosphorous and relevant trace elements for the growth of phytoplankton • The new organic matter and nutrients supported by Saharan dust are transferred across the food web • Skipjack tuna migrates tracking the seasonal shift of Saharan dust deposition in the Atlantic • The most important fishing area of Atlantic skipjack tuna is located off NW Africa in waters affected by massive Saharan dust deposition • Dust deposition over upwelling waters support zooplankton rich areas, optimal for fish larvae, molluscs, cephalopods, and large predators [ABSTRACT FROM AUTHOR]

We herein explore the connections between the current condition of ecology concerning to sustainable development and the statement of Rutherford regarding the importance of physics to understand sustainability and biological conservation. The recent emergence of organic biophysics of ecosystems (OBEC) may constitute a feasible alternative to fill the gap between conventional ecological thinking and physics, especially thermodynamics. However, our comprehension of sustainability and biological conservation is influenced by the interactions between information and entropy, because we tend to exclude parts of the biosphere as well as their relationships among them. We explore the use of a holistic analysis of sustainability and biological conservation using physics, and also establish a parallelism between Maxwell's demons and human beings. Lastly, the ecological meaning of the hypothetical feasibility of Maxwell's demon at the anthroposphere scale is analyzed starting from the objections of von Smoluchowski, Szilard and Bennet. [ABSTRACT FROM AUTHOR]

Uneaten feeding pellets and fish released faeces cause the most severe impact on the benthos beneath aquaculture offshore sea-cages. A modelling tool, ‘MACAROMOD', composed of particulate waste dispersion and benthic response, was developed to predict the environmental disturbances of offshore sea-bream ( Sparus aurata ), sea-bass ( Dicentrarchus labrax ) and meagre ( Argyrosomus regius ) aquaculture in the Macaronesian region (oceanic archipelagos in the north-eastern Atlantic). MACAROMOD was tested at 8 sites (7 farms in the Canary Islands and 1 farm in Madeira), hence covering a high variability in oceanographic and environmental conditions. In general, a low percentage of lost pellets was found (3%), while a high rate of pellets were consumed by wild fishes (97%). Considering all studied sites, significant correlations were shown between observed and predicted solid fluxes (R 2 = 0.89), and also between solid fluxes and the depositional footprint on the benthos, by taken advantage of observed and predicted values of the ecological status AMBI index (R 2 = 0.6966). A flux threshold of 12 kg solids m −2 yr −1 was predicted as a boundary from which ecological degradation occurs for the study region. MACAROMOD is therefore a valid tool to improve planning and monitoring Macaronesian aquaculture. [ABSTRACT FROM AUTHOR]

Seagrasses like Posidonia oceanica provide a wide range of benefits for the ocean and for the planet. Efforts in conservation and restoration have increased in the last 20 years to preserve P. oceanica meadows; a plenty of works have been conducted to develop restoration and planting actions as a way to offset the regression of this seagrass in the Mediterranean Sea. We here compile the information on these studies to make a bibliographic review. The review results showed that seedlings grow better on dead matte and rock covered with algae in calm waters with moderate depths. We highlighted the gaps of knowledge on restoration actions of Posidonia oceanica. Furthermore, with intensive and integrative work these gaps could be filled in the upcoming years. • Seedlings grow better on dead matte and rock covered with algae. • Seedlings survival increase in calm waters with moderate depths. • Gaps of knowledge on restoration actions of Posidonia oceanica are highlighted. [ABSTRACT FROM AUTHOR]

Intertidal mollusks are subjected to an intense environmental pressure, from human-induced stressors, mainly harvesting, to competition for food and space with other species. Here we used mollusk shell size as a measure of size distribution and reproductive potential of intertidal limpets. Two species of exploited limpets ( Patella candei crenata and Patella aspera ) were monitored throughout the littoral of Tenerife (Canary Islands, NE Atlantic Ocean), an overpopulated island with a high coastal pressure. The exploitation of these two limpet species is controlled by regional legislation, with seasonal closures and limits of harvest for professional (10 kg) and recreational harvesters (3–5 kg). A long-term comparison (1994–2014) of limpet size has been conducted as a surrogate of the state of conservation of these two limpets. Both species showed populations dominated largely by small-sized individuals (<30 mm) and a lack of large adults (>60 mm). The proximity to coastal settlements was not a factor to explain limpet assemblage structure. The temporal (1994–2014) comparative study showed a sharp decrease in the mean size of both limpet species (7 mm in P . aspera and 5 mm in P . candei crenata ). These results might be indicative of overharvesting of both species in Tenerife. The conservation of the two studied species needs to be accomplished by the strict fulfillment of current protective strategies, as well as the creation of marine protected areas where intertidal harvesting is totally banned all over the year. [ABSTRACT FROM AUTHOR]

Seagrasses are experiencing fragmentation and regression globally; thus, protection and recovery of meadows are a preservation priority. However, conservation actions must consider inherent regional conditions, since certain coastal areas are not suitable for the settlement of extensive meadows. Likewise, small oceanic archipelagos are not always able to fulfil the habitat requirements of seagrass habitats but can harbour small patches that in turn provide unique research opportunities. In this study, we focused on the seagrass Cymodocea nodosa in the archipelago of Madeira (NE Atlantic Ocean). Here we compile historical and contemporary records of this species along with characterization of associated communities (fish and invertebrates). A bionomic map with potentially suitable areas for the establishment and settlement of this species is also included. Lastly, we highlight coastal management and restoration actions and future research directions to preserve this species in Madeira Island. [ABSTRACT FROM AUTHOR]

Lack of knowledge of the marine realm may bias our perception of the current status and threats to marine biodiversity. Less than 10% of all ecological literature is related to the ocean, and the information we have on marine species that are threatened or on the verge of extinction is scarce. This lack of information is particularly critical for isolated areas such as oceanic archipelagos. Here we review published and grey literature on the current status of marine organisms in the Canary Islands as a case description of the consequences that current out-of-sight out-of-mind attitudes may have on this unique environment. Global change, as represented by coastal development, pollution, exotic species and climate change, are currently affecting the distribution and abundance of Canarian marine organisms, and pose multiple threats to local species and communities. Environmental risks are significant at community and species levels, particularly for threatened species. Failure to address these trends will result in shifts in local biodiversity with important ecological, social, and economic consequences. Scientists, policy makers, educators, and relevant societal groups need to collaborate to reverse deleterious coastal biodiversity trends. [ABSTRACT FROM AUTHOR]

Abstract: Desalination plants generate large volumes of hypersaline brine, likely affecting recipient communities. We aimed to assess whether proximity to a brine discharge point altered the abundance, assemblage structure and diversity of macrobenthic fauna. Collection of samples took place twice (May 2008 and January 2009) at 0, 15 and 30m away from a brine discharge point. Total macrofaunal abundance increased with increasing distance from the brine discharge point, though the magnitude of differences was inconsistent between successive years, probably as a result of a change in particle size distribution. Proximity to the brine discharge point also altered patterns in macrofaunal assemblage structure. The macrofaunal species density was higher at 15 and 30m than at 0m. In conclusion, proximity to a brine discharge point significantly altered the ecological pattern of macrobenthic fauna, though disentangling the effect of the increase in salinity from particle size distribution remains undetermined. [Copyright &y& Elsevier]

Abstract: Interannual variability (2003–2008) of meiofaunal assemblages were analyzed in sediments beneath fish cages (Impact group) and in areas not affected by aquaculture activities (Control group). Organisms responded with spatial and seasonal variation in meiofauna assemblages, with an abrupt increase of abundances in locations beneath fish cages throughout the study period. This increase was greater during the last sampling year (2008) and mainly due to high abundances of nematodes. Univariate analyses showed differences between control and impacted sites at both sites, however, only significant variations were found in Los Gigantes, which are consistent with seasonal meiofauna variations throughout the study period. These results are partially explained by differences in current velocity between both sampling areas. The Ne/Co index showed the same trend and it seems to be a reliable index in sediment slightly affected by aquaculture wastes. This index is especially recommended in oligotrophic areas (e.g. Canary Islands) where meiofaunal assemblages are poorly represented in terms of abundances. [Copyright &y& Elsevier]

Oil and gas platforms act as artificial habitats for a myriad of marine organisms. In this study, we used opportunistic remotely operated vehicle (ROV) data to describe fouling assemblages through the characterization of functional groups in the Al Shaheen oil field, situated in Qatari waters. The surveys showed a strong vertical stratification, with the number of functional groups increasing from the surface to the bottom. In addition, the majority of functional groups had their highest frequency of occurrence in the 35–60 m interval. In turn, multivariate analyses showed a slight structure among platforms with different ages. The lowest number of functional groups occurred in the early ages (2–3 years old), and some groups either increased or decreased their frequency and abundance along the years. A step further is now required to determine whether these platform foundations should be converted to reefs after their decommissioning (i.e., Rigs to Reefs approach). • There is a strong structure in the vertical distribution of fouling organisms inhabiting offshore platforms in the Arabian Gulf. • The composition, abundance and frequency of occurrence of fouling organisms inhabiting platforms along the years. • Azooxanthellate scleractinian corals and soft corals are commonly observed. [ABSTRACT FROM AUTHOR]

Displaying an appropriate dispersal intensity (DI) in response to environmental fluctuations may determine if a given species goes extinct or not. Thus, developing indicators of the DI necessary to harness a given ecological niche breadth is urgent due to the changing latitudinal boundaries between the Earth's great climate belts because of global warming. So, a better assessment of extinction risk should require DI as a complementary indicator. However, the IUCN Red List, indirectly linked to niche assessments, does not take into account DI, and its values are expressed on an ordinal scale. In contrast, there is a theoretical consensus about the link between DI and extinction risk, as well as about the continuous nature of species extinction, which therefore should be measured on a ratio scale. This paper proposes solutions to the above-mentioned issues. Assuming the trait of ergodicity, successfully applied in several publications in ecology so far, measurements of the average values of recent indicators of DI of birds at the species level as well as at the plot level were performed starting from 52 samplings of roadkill events, in eight European countries. DI values were correlated with the respective values of extinction risk reported by the IUCN Red List. Collaterally, a comparative study between DI and two key environmental variables (traffic intensity, and average temperature over land areas) was performed. Inverse and significant correlations between DI and the ordinal scale of IUCN Red List values were obtained, indicating that higher DI values seem to reduce extinction probability. Our results also show that birds seem able to display rapid adaptive behaviors to the increase of traffic intensity. It was found that DI peaks of European birds are associated with deviations of only half a degree Celsius above the general background of temperature over land areas. This set of results, based on a new theoretical framework (Organic Biophysics of Ecosystems –OBEC–; see references and explanatory notes in the main text), is in favor of the appropriateness to rescue the classical foundations of ecosystem ecology based on interdisciplinary links between ecology and physics to promote a better management of the Anthropocene challenges, all of them typified by interdisciplinary traits that require holistic approaches. [ABSTRACT FROM AUTHOR]

Homing behaviour is frequently observed in marine intertidal invertebrate species. This behaviour may help species to deal with the environmental variability of the intertidal, providing shelter during low tides and areas to explore and search for food during high tides. The capacity of individuals to show fidelity behaviour should be an adaptive trait, due to the uncertainty that finding a new shelter in each tidal cycle implies. Chiton granosus is a common polyplacophora of the Southeastern Pacific rocky intertidal zone. During high tides, individuals move throughout the substratum in search of food; meanwhile, they are found within crevices in groups of variable sizes during low tides. According to previous works, this species shows some degree of fidelity to these shelters. Using field and laboratory experiments, we herein evaluate the factors determining the degree of site fidelity in C. granosus , taking into account the distance travelled from the shelter and food availability. Also, we evaluated the importance that chemical signs from the pedal mucus have in aiding C. granosus to return to its refuge. Field observations showed that C. granosus presents variable levels of site fidelity covering a maximum distance of 50 cm from its shelter. Laboratory results suggested that fidelity to shelters is related to the proximity of food sources. Chemical cues from the pedal mucus could be used to find the shelter after exploratory activities during high tides. • Homing behaviour was observed in the intertidal mollusk Chiton granosus. • Site fidelity was related to the proximity of food sources. • Site fidelity showed levels of fidelity up to distances of 50 cm from the shelter. • Chemical signs are important to return to the refuge (crevice). [ABSTRACT FROM AUTHOR]

The interaction between bottom-up and top-down processes in coastal ecosystems has been scarcely studied so far. Temporal changes in trophic interactions of Zostera marina along the Swedish west coast are relatively well studied, with the exception of epifaunal communities. Epifauna was used as a model study to explore resource (bottom-up) or predator (top-down) regulated in a vegetated ecosystem. We conducted a 21-year comparative study (1997 and 2018) using epifauna of 19 Zostera marina meadows along the Swedish Skagerrak coast. Large changes were observed in the composition of small (0.2–1 mm) and large (>1 mm) epifauna. In the small-sized epifauna, the nematode Southernia zosterae and harpacticoids showed an increase of 90% and a decrease of 50% of their abundances, respectively. In the large-sized epifauna, the polychaete Platynereis dumerilii and chironomid larvae were absent in 1997 but thrived in 2018 (>2000 ind. m−2). Mesoherbivores (Idoteids and gammarids) were locally very abundant in 1997 but disappeared in 2018. An 83% decline of mytilids settling in Zostera marina leaves was observed. Our results showed that epifauna is predominantly top-down regulated. An integrative framework of the study area is outlined to shed light on the causes and consequences of the environmental shifts reported in Zostera meadows from the northern Skagerrak area throughout the last three decades. • Epifaunal communities greatly varied from 1997 to 2018. • Epifauna is mainly top-down regulated. • Filamentous algae thrive in the study region. • Several shifts on Zostera marina meadows from the Skagerrak coast [ABSTRACT FROM AUTHOR]

• Mesh sizes used in fish trap fisheries rank from 12.5–64 mm. • Catch rates varied from 0.16–23.9 kg/trap. • Some targeted species increased in abundance, but most fish stocks were in decline. • Ghost fishing mortality could be minimized by the presence of escape mechanism. • The majority of fish trap fisheries remain poorly managed. Fish traps are extensively used in tropical and subtropical reef fisheries. Despite this, there is a significant lack of extensive and consecutive research concerning the basic aspects of trap fishing. We herein compile the available information from the main coral and rocky reef fish trap fisheries, and compared their main aspects (i.e., mesh size, CPUE, catch composition, ghost fishing, and management) to assess the dynamics of these fisheries and their environmental impact. The analysis revealed that most fish stocks showed declining trends, with only few species under heavy management being capable of withstanding high fishing pressure. In other fisheries, due to fishing down the web, miscellaneous reef fish comprised the bulk of the catch, while the proportion of high-value landed species was insignificant. Gear restrictions remain the most common management method in trap fisheries; however, even the minimum mesh size has not been ubiquitously enforced, while due to great variability of targeted fish species, use of a uniform mesh size is highly unlikely. Other management tools, such as, restrictions in effort, size, and species, temporal and spatial closures were also widely used, but effective only when well enforced and interconnected. Rates of trap loss widely differed as well as the reported rates of ghost fishing mortality. In most cases, incorporation of escape panels resulted in almost complete elimination of ghost fishing. However, further research is required concerning these issues. [ABSTRACT FROM AUTHOR]

Post-settlement movement has been reported mainly in marine species with low or reduced adult mobility, where distribution varies in accordance with ontogeny, thus avoiding or reducing environmental stress or biological interactions. Mussels show high dispersal at the larval stage, and settlement is a highly complex process in which larvae must choose an appropriate site to attach. Although adults are mainly sedentary, it has been shown that they move on a local scale during the benthic phase in response to physical and biological factors. Semimytilus algosus and Perumytilus purpuratus are two bioengineer mussel species cohabiting most of the Chilean rocky shores. While S. algosus occurs in the low intertidal zone, P. purpuratus dominates the mid and mid-high zones. Field and laboratory experiments have shown that S. algosus is a weak competitor with respect to P. purpuratus , and post-settlers present high mobility to relocate in the intertidal. Under this scenario, we evaluated the dispersal behavior of juveniles and adults of S. algosus as a potential response to competition with P. purpuratus. We also measured the attachment strength of S. algosus in the presence of its competitor, as a measure of its escape response ability. Our results showed that the presence of P. purpuratus increased the movement activity of juveniles and adults of S. algosus and decreased their attachment strength. Field experiments carried out with marked individuals in a Chilean rocky shore, showed that S. algosus exhibits higher local dispersion in the zone where P. purpuratus is present. Mussels' high dispersal ability throughout the whole benthic phase may not only serve to reach the optimal physiological position in the intertidal, but also to reduce competition interaction. • Post-settlement movement in mussels has been reported to avoid or reduce environmental stress or biological interactions. • We evaluated post-settlement dispersal in S. algosus as a potential response to competition with P. purpuratus. • Laboratory and field data showed that the presence of P. purpuratus increases the movement activity of S. algosus. • Post-settlement escape ability may reduce competition and help to explain distributional patterns of both mussel species. [ABSTRACT FROM AUTHOR]

Abstract Ocean sprawl is replacing natural substrates with artificial alternatives. We hypothesized that, after submersion, high occupancy, high mobility species colonize artificial substrates faster than low occupancy, low mobility species, a biodiversity divergence that will slowly fade out with time. Using quantitative visual census of species in 10 artificial and their adjacent natural substrates, we tested for the existence and temporal evolution of this divergence. Assigning species to one of three occupancy and one of three mobility categories, we found that artificial substrates increased the performance of high mobility, high occupancy species while decreased the performance of low occupancy species with medium and low mobility. This biodiversity divergence remained unchanged over the 50-year underwater timespan of the artificial substrates investigated. Our results suggest that proliferation of artificial substrates is building up a biodiversity loss driven by the least conspicuous and uncommon benthic and sessile species that is undermining coastal marine biodiversity. Highlights • Artificial and natural substrates seem to share common biodiversity. • Species occupancy and mobility are critical traits to detect differences. • High mobility, high occupancy species thrive in artificial substrates. • Medium and low mobility species with low occupancy thrive in natural substrates. • Biodiversity differences show no fade-out trend in over 50 years of submersion. [ABSTRACT FROM AUTHOR]

The theory of food chains, and therefore the assembly and modifications of trophic pyramids depending on environmental influences, is an essential part of modern ecosystem ecology. A general model of energy pyramids based on a fruitful but simple analytical connection between ecology and conventional physics has been proposed by Rodríguez et al. (2015a). However, this model has several drawbacks. Among them: it has only been tested for isolated taxocenes and under stationary ecological conditions (SEC). Besides, it has not been tested if the internal distribution of typical species groups within the obtained pyramids follows the expected pattern according to the well-known trophic habits of these typical groups of species. This article starts with a brief summary of the most relevant drawbacks of our conventional point of view about trophic pyramids in order to highlight the differences, as well as the advantageous coincidences, of the above-mentioned new model in comparison with our orthodox point of view about trophic pyramids. This summary connects with a description of the obstacles that should be surpassed in order to develop a more general model ( i ) valid at the inter-taxocene scale and ( ii ) fully useful to model systems under non-stationary ecological conditions (NSEC). The article proposes two simple mathematical modifications of the original model in order to achieve items ( i ) and ( ii ). In subsequent sections, the effectiveness of these modifications is tested by using field data from 25 samplings belonging to 6 different taxocenes, by including a majority of zooplankton data from a human-made highly eutrophic reservoir (Acton Lake; Hueston Woods State Park, Ohio, U.S.A.) with frequent and contingent episodes of NSEC. According to our results, it is not possible to reject either the hypothesis about the validity of modifying the original equation to model ecosystems as a whole under NSEC or the hypothesis that typical species groups follow a distribution within their respective pyramid in agreement with the expected pattern according to their trophic habits. In summary, this article is an additional step in favor of the usefulness of rescuing and expanding the original epistemological roots of ecosystem ecology in connection with conventional physics. [ABSTRACT FROM AUTHOR]

Despite the well-known thermodynamic traits of ecosystem functioning, their description by means of conventional physics should be regarded as incomplete, even if we take into account the most recent advancements in this field. The analytical difficulties in this field have been especially complex to get a reliable modeling of species diversity per plot ( H p ) by endowing this indicator with a fully clear theoretical meaning. This article contributes to resolve such difficulties starting from (a) the previous proposal of an ecological state equation, and (b) the preceding empirical finding of an ecological equivalent of Planck's constant at the evolutionary scale. So, in the first instance, this article proposes an equation for density distributions of H p values (ED H ) based on a simple transformation of the Maxwell–Boltzmann distribution for molecular velocity values (M–B D v ). Our results indicate that the above-mentioned equation allows an appropriate fit between expected and observed distributions. Besides, the transformation from M–B D v to ED H establishes connections between species diversity and other indicators that are consistent with well-known ecological principles. This article, in the second instance, uses ED H s from a wide spectrum of surveys as an analytical framework to explore the nature and meaning of stationary trophic information waves (STIWs) whose stationary nature depends on the biomass-dispersal trade-off in function of H p values (B-D TO- H ) that characterizes the most of the explored surveys. B-D TO- H makes these surveys behave as ecological cavity resonators (ECR) by trapping functional oscillations that bounce back and forth between the two opposite edges of the ECR: from r -strategy (at low biomass and diversity, and high dispersal) to K -strategy, and vice versa. STIWs were obtained by using the spline-adjusted values from the arithmetical difference between standardized values of species richness ( S ) and evenness ( J ′) in function of H p values (i.e., a 2D scalar space H p , S–J ′). Twice the distance on the abscissas (2Δ H p ) between successive extreme values on the ordinates (whatever a maximum or a minimum) along the above-mentioned spline adjustment was taken as the value of ecological wavelength ( λ e ). λ e was assessed in order to obtain the value of the ecological equivalent of Planck's constant ( h e ec ) at the intra-survey scale that was calculated as: h e ec = λ e × m e × I e ; where m e : individual biomass, and I e : an ad-hoc indicator of dispersal activity. Our main result is that the observed value of h e ec 's mantissa is statistically equivalent to the mantissa of the physical Planck's constant ( h = 6.62606957E − 34 J s) in all of the discontinuous (i.e., with interspersed categories in which n = 0) statistical density distributions of H p values per survey. This means that h e ec = 6.62606957E φ J e nat/individual, where φ = − x i , …, −3, −2, −1, 0,+1, +2, +3, …,+ x i depending on the type of taxocenosis explored. That is to say, h e ec indicates the minimum amount of energy exchange allowed between two individuals. The exploration of the analytical meaning of this result in the final sections of the article explains why quantum mechanics (QM) is a useful tool in order to explain several key questions in evolutionary biology and ecology, as for example: the physical limit of adaptive radiation; the balance between competitive exclusion and functional redundancy to promote species coexistence by avoiding the negative effects of competitive exclusion; the apparent holes in the fossil record; the progression of body size along a wide spectrum of taxa as a general evolutionary trend; the non-continuous nature of net energy flow at the ecosystem level; the way in which the energy level is stabilized under stationary ecological conditions; the reasons of the higher sensitivity of high diversity ecosystems under environmental impact despite their higher stability under natural conditions; the tangible expression of complex concept as ecological inertia and elasticity; as well as the increased risk from pushing the biosphere until a rupture limit because of the potential discrete behavior of ecological resilience in the large scale due to the quantum nature of ecosystem functioning. [ABSTRACT FROM AUTHOR]

A new and wide area of theoretical and methodological overlap between ecology and conventional physics has emerged from the development of an ecological state equation and its consequences. Specifically, the discontinuous (discrete) increase of the ecological equivalent ( k e ) of Boltzmann's constant ( k B ) suggests a startling hypothesis: most general principles of quantum mechanics could be valid at the ecosystem level. In this paper, we show a single result supported on previous theoretical results as well as on already published data: that a significant and robust straight line adjustment with an intercept at the coordinate's origin between the mean value of eco-kinetic energy per individual and k e at the inter-taxocenosis scale has a regression constant (slope) whose mantissa coincides with the Planck's constant mantissa at the 1000th level. From this result, we propose two simple equations, with increasing exactness, to assess the expected mean values of individual eco-kinetic energy per survey at the inter-taxocenosis level with a reliable statistical adjustment in comparison with the respective observed values. This result means that the evolutionary process as a whole could be understood as a “staggered propulsion” of a tiny initial clot of life that has been ecologically driven across a discontinuous evolutionary gradient of exchange of information by trophic energy with an increment rate ruled by constant quantum parameters. The potential meaning of this finding for evolutionary ecology and our understanding of the ecosystem functioning is analyzed, and the future challenges to develop a holistic theoretical framework based on this result are stated. [ABSTRACT FROM AUTHOR]

Conventional thermodynamics and statistical mechanics deal with the study of physical systems under equilibrium conditions (EC). Internal EC at a temperature that differs from the environment temperature are sustained, in general, by some type of artificial boundaries imposed with research aims or with quotidian utility goals in many kind of domestic appliances; the typical example of academic lab is a closed system immersed in a thermal bath which keeps the temperature constant. However, the ecosystem is a far-from-EC open system. Therefore, conventional thermodynamics and statistical mechanics tend to be orthodoxly regarded as limited to explain the ecosystem functioning since, at the first glance; there seem to be several essential functional differences between it and the previously-mentioned kind of physical systems. This viewpoint averse to conventional physics is paradoxical in regard to the current ecological paradigm given the fully thermodynamic foundation of ecosystem ecology. However, additional evidence in favor of the usefulness of conventional physics to describe the ecosystem functioning have recently been published, pointing out to the possibility that the analytical approach to ecology based on our undergraduate knowledge of physics, unfortunately, could have been hastily neglected before producing its most valuable results. This paper, fully based on the above-mentioned evidence, performs an unavoidable additional step in order to complete such a proposal by showing that the Boltzmann distribution of molecular energy values can be simply and successfully adapted to model the distribution of values of a proxy for trophic energy across an increasing gradient of energy levels, in a very similar fashion to that of a standard trophic pyramid. Starting from this result and by using a balanced combination between plausible theoretical considerations and abundant empirical data, we analyze why this approach is in agreement with well-known ecological principles, at the same time that we explore the general empirical advantages and aftermaths derived from this suggestion. Finally, the article explores the usefulness of the thermo-statistical modeling of eco-kinetic energy per plot to understand those essential physical factors that: promote biological evolution, facilitate species coexistence, can explain the holes in the fossil record, and enhance our current viewpoint about the ecological meaning of entropy. In summary, this article provides simply understandable additional information that indicates, despite its far-from-EC nature, any natural ecosystem is not far away from the most orthodox principles of conventional physics. [ABSTRACT FROM AUTHOR]

Abstract: Marine vegetated habitats, e.g. seagrass meadows, deliver essential functions and services to coastal ecosystems and human welfare. Impacts induced by humans, however, have facilitated the replacement of seagrasses by alternative vegetation, e.g. green rhizophytic seaweeds. The implications of habitat shifts for ecosystem attributes and processes and the services they deliver remain poorly known. In this study, we compared ecosystem structure and function between Cymodocea nodosa seagrass meadows and bottoms dominated by Caulerpa prolifera, a green, native, rhizophytic seaweed, through 5 ecological proxies: (i) primary production (via community metabolism), (ii) composition and abundance of epifauna (a proxy for provision of habitat for epifauna), composition and abundance of (iii) small-sized (juvenile) and (iv) large-sized (adult) fishes (proxies for provision of habitat for fishes), and (v) sediment retention (a proxy for sediment stabilization). Four of these proxies were greater in C. nodosa seagrass meadows than in C. prolifera beds: gross primary productivity (∼1.4 times), the total abundance, species density and biomass of small-sized fishes (∼2.1, 1.3 and 1.3 times, respectively), the total abundance and species density of large-sized fishes (∼3.6 and 1.5 times, respectively), and sediment stabilization (∼1.4 times). In contrast, the total abundance and species density of epifauna was larger (∼3.1 and 1.7 times, respectively) in C. prolifera than in C. nodosa seagrass beds. These results suggest that ecosystem structure and function may differ if seagrasses are replaced by green rhizophytic seaweeds. Importantly, ecosystem functions may not be appropriate surrogates for one another. As a result, assessments of ecosystem services associated with ecosystem functions cannot be based on exclusively one service that is expected to benefit other services. [Copyright &y& Elsevier]

Abstract: The common octopus (Octopus vulgaris), a promising species for aquaculture, spawns easily under captivity from mature females (usually above 1kg wet weight). Octopus juveniles and adults are collected from nature to obtain eggs and paralarvae for aquaculture development trials. In July 2011, a very small female (150g wet weight but with an age estimation of 300 days-old) spawned almost 77,000 paralarvae. Malformations of paralarvae were noticed in the first spawning days, namely the absence of arms. Despite not being lethal, these abnormalities might be derived from the physiological condition of the breeding specimen (the female's lower weight to the estimated amount of living days), which might be eventually related to nutritional unbalances or genetic parameters that were transferred to the eggs. [Copyright &y& Elsevier]

Particulate wastes (uneaten feed and faeces) are assumed to cause the most intense impact on the benthic community beneath aquaculture cages. Settling velocity of uneaten feed pellets and faecal material, required as model input data, represents a key parameter for waste dispersion models. In this study, settling velocity rates of two commercial meagre (Argyrosomus regius) feed pellets (EFICO Sigma 578 — Biomar 9 and 12mm) and faecal material from two size categories of cultured meagre (small: 0.821±0.157kg; large: 1.663±0.371kg) were determined. Settling velocity for Biomar 9 and 12 pellets followed a normal distribution, with mean values of 9.83±0.17cms−1 (n=78) and 9.67±0.28cms−1 (n=76) respectively and 9.75±0.24cms−1 for all data (n=154). On the contrary, faecal particle settling velocity data did not comply with normal distribution assumptions. Settling rates were not significantly different (P =0.37) between the two meagre size categories, but significant variation (P <0.001) in settling velocity between all interval categories was found. Settling velocities generally increase with particle size. Particles with slow settling velocities (<1cms−1) dominated samples (87.0%) and fast settling velocities (2–3cms−1) were uncommon, with values of 1.1%. Yet, particles with small settling velocities (<1cms−1) only account for 38% of the mass. Particles with medium settling velocities (1–2cms−1), in which frequency distribution was much lower (12%) had the highest mass distribution, 51%. Waste dispersion modelling scenarios based on specific meagre settling feed and faeces settling velocity data, resulted in a wider dispersion area and lower flux values, hence in a smaller severity of predicted deposition, when compared with model output scenarios based on non-specific sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata) settling velocity data. [ABSTRACT FROM AUTHOR]

• Fishery operations induced biases in predator diet and cannibalism estimation. • Methods to estimate daily ration and consumption based on stomach content are underestimated. • Bioenergetic methods are better estimators of daily ration and consumption. Only few studies on the feeding and cannibalism behavior of the jumbo squid have been conducted in the Humboldt Current System despite this species is currently considered an important economic resource. It is possible that the diet of this ommastrephid squid varies throughout the year, among areas and body size. Therefore, we herein collected jumbo squids from commercial catches during January to December 2014 using purse-seine nets. The stomach contents were analyzed in terms of frequency of occurrence, number, and weight of prey items. The diet composition was analyzed using Detrended Correspondence Analysis. The variation of jumbo squid diet composition was evaluated from different biological and temporal predictors (sex, maturity, body size and months), considering and analyzing cannibalism. Daily ration was estimated using three methods to calculate consumption and consumption/biomass ratio. Our results suggest that there are significant differences in diet throughout the year, among sizes, and between sexes, however, no differences were found according to the interactions of these factors, except for the interaction between sex and month. In addition, significant differences were detected for each factor (sex, month and body size) when evaluating cannibalism, although these differences were only significant when factors were evaluated independently. Body size was the best predictor of diet composition, richness and cannibalism variation. Stomach content weight was highly biased due to the advanced level of digestion, which in turn biased the diet based on weight, daily ration and consumption analyses. In this sense, the bioenergetic model based on water temperature fitted better than models based on stomach content weight and body mass. These results showed that D. gigas mostly predates on crustaceans and cephalopods, which contrasts with most ecosystem models that suggest that this species highly predates on commercially-exploited fish species. [ABSTRACT FROM AUTHOR]

The species occurrence of mesopelagic fish collected in the scattering layers was studied across the Indian Ocean subtropical gyre during the dry season (2015). Ocean eddies can retain zooplankton and plastic debris, and determine biological composition through advection. The conditions inside the gyre were stabilised by low chlorophyll- a concentrations and a deep nutricline. A diverse assemblage of mesopelagic fish, dominated by myctophids, exhibited diel migrations to the upper water layers for feeding since the early night. Myctophids were concentrated ca. 100 m depth, where the deep chlorophyll maximum was located, and coinciding with the nutricline. Another group of mesopelagic fish remained in deeper waters during the daytime, with a higher occurrence of Stomiiformes (Phoshycthyidae and Sternoptychidae) at the 500–600 m Deep Scattering Layer. Moreover, the diets of 220 myctophid specimens belonging to the species Ceratoscopelus warmingii , Diaphus effulgens , and Symbolophorus evermanni , were investigated based on stomach content analysis. Calanoid copepods, mainly Pleuromamma abdominalis , made up 30% of the diet in the three myctophid species, with interspecific differences in the preferred second item: C. warmingii preferred ostracods, D. effulgens , non-calanoid copepods, and S. evermanni , euphausiids. Thus, partial dietary segregation was observed among the three species. We hypothesized that these myctophid diets differed between stations located at the gyre core and its outer edge. Any dietary pattern indicating aggregation of food resources, or an enhancement of the foraging opportunities for myctophids, was discerned as an effect of the gyre advection. However, prey composition diverged between the core and the outer edge stations regardless of the fish species, with a higher dietary representation of P. abdominalis and euphausiids (migratory zooplankton) in the individuals collected in the core-influenced area. A total of six plastic pieces were present in the stomachs of D. effulgens and S. evermanni , in contrast with the high presence of plastic particles found at the surface in most sampling stations (average number of plastic pieces was 41 per hour). The selected myctophid species did not appear to be important transport vectors for microplastics in comparison with species from other oceans. [ABSTRACT FROM AUTHOR]

Abstract Intertidal limpets are subject to harvesting pressure in regions, e.g. oceanic islands, where marine organisms are a more accessible source of protein. These molluscs are very sensitive to human exploitation which often results on a decrease of their densities and an over-representation of immature individuals, because of the loss of large-sized reproductive specimens. Two species of exploited limpets (Patella aspera and Patella candei) were assessed throughout 21 years, before (1996–2006) and after (2007–2017) the implementation of conservation measures for their sustainable management in Madeira (North-eastern Atlantic Ocean). Different levels of anthropogenic pressure were also taken in account in this comparative study: (i) proximity to coastal settlements ("Near" vs. "Far") and (ii) accessibility to the coast (North vs. South), that may be considered surrogates of harvesting pressure on the intertidal of Madeira. The present results showed that the stocks of P. aspera and P. candei are slightly recovered after regulatory measures entered into force, with an increase of mean shell length and dominance of reproductive individuals (>40 mm). P. aspera populations showed a clearer effect mainly due to the higher exploitation rate relative to P. candei. Conservation measures prompted a positive effect on both exploited limpet species, but further assessment studies are necessary to address the evolution of stocks over time. Highlights • Populations of P. aspera and P. candei were assessed throughout 21 years in NE Atlantic. • Impact of harvesting effort on the stocks of P. aspera and P. candei was evaluated. • Effect of proximity and accessibility on the stocks was analysed. • Stocks of limpets are slightly recovered after regulatory measures entered into force. • Further assessment studies are warranted to address the evolution of stocks over time. [ABSTRACT FROM AUTHOR]

Abstract Porcelain crabs inhabit from upper intertidal to subtidal habitats. These environments are characterized by highly variable environmental conditions, which subject species found in these habitats to stress. In this study, we compared reproductive traits of mothers [i.e. fecundity, reproductive output (RO), dry weight, organic matter] and physiological parameters of their offspring (i.e. wet weight, water content, dry weight, organic matter, lactate content of embryos) of three species of porcelain crabs that inhabit the Southeastern Pacific: Petrolisthes laevigatus (upper intertidal); P. violaceus (low intertidal); Allopetrolisthes punctatus (subtidal). Overall, female P. laevigatus had lower fecundity (802 ± 115 vs. 4181 ± 1097 embryos) and amount of organic matter in their embryo masses (0.053 ± 0.006 vs. 0.27 ± 0.025 g) but higher RO values (1.34 ± 0.34 vs. 0.20 ± 0.07) than Allopetrolisthes punctatus. In addition, P. laevigatus embryos had higher organic matter content (81.09 ± 28.8 vs. 64.54 ± 6.1 μg), higher water content (188.6 ± 91.9 vs. 152.4 ± 30.8 μL) and higher lactate content (0.26 ± 0.04% vs. 0.07 ± 0.01% dry weight) than that found in A. punctatus embryos. Furthermore, females and embryos of P. violaceus showed low values and similar to those observed in P. laevigatus. As a potential strategy to increase survival of the offspring, P. laevigatus seems to invest a large portion of its energy in production of high quality embryos, despite costs to fecundity. This study reveals that porcelain crabs have physiological adaptations during their ontogeny that allow them to survive in fluctuating environments. [ABSTRACT FROM AUTHOR]

Conventional ecology lacks a non-contingent theory on the relationship between abiotic, biotic and anthropogenic factors under natural or quasi-natural conditions. As a result, since ecology is the science that studies the interaction between ecological factors in nested complex systems, we should recognize that ecology needs significant enhancements to understand the functioning of ecosystems. This article combines the ecological state equation (ESE, one of the earliest models derived from the Organic Biophysics of Ecosystem –OBEC), with abundant field data of abiotic factors, biotic factors and human factors from inland water rotifers and crustaceans (1022 samples taken over 21 years), litter invertebrates in laurel forest and pine forest (308 samples), and marine interstitial meiofauna of sandy beaches (90 samples). This has been done in order to obtain additional empirical evidence on the intrinsic trend to stationarity in the long run, even in perturbed ecosystems (man-made eutrophic water reservoirs, forest vegetation affected by traffic, and coastal ecosystems close to disposal points of sewage that are fully or partially treated, respectively to the above-mentioned taxocenes), and the relationship between the above-mentioned ecological factors. Our results indicate that there is a complex natural arrangement that intertwines the trend to stationarity and the resilience capability of ecosystems with a clear pattern of hierarchical setup between ecological factors. This is reflected by the role of ESE as a trophodynamic interface in hierarchical statistical models (cluster analysis) because they involve, in the following order of increasing rank: lower level abiotic factors (a.f.), biotic factors (b.f.), the holistic combination of state variables included in the ESE and, finally, higher level human factors (h.f.). In such a way, there is a clear trend to a hierarchical assemblage in agreement with the evolutionary origin of ecological factors in the deep time, as well as in regard to the net direction (⟵) of ecological homeostasis: a.f. ⟵ b.f. ⟵ h.f. In this setup, the ESE accomplishes a key liaison role, because it reflects a long run trend to stationarity which allows an essential degree of ecological stability, as well as our capability to classify ecosystems, in spite of the random influence of ecological perturbations in the short run. The above-mentioned set of additional evidence can be regarded as a step to develop a non-contingent theory about the relationship between abiotic, biotic and anthropogenic factors. Furthermore, since the OBEC, in its origin, deals with only the dynamics of biotic variables, this is the first time that the interaction between one of its main models and other kind of ecological factors is studied yielding reliable results in the process. [ABSTRACT FROM AUTHOR]

The emergence of organic biophysics of ecosystems (OBEC: an interdisciplinary approach supported by thirteen previous articles in order to get a non-contingent explanation of ecosystem dynamics) may close the gap between the foundation of ecosystem ecology in classical thermodynamics and the paradoxical fact that conventional thermostatistics is currently regarded as useless to explain ecosystem functioning. The measurement of eco-kinetic energy ( E ep ) was the first step of OBEC. However, E ep assesses trophic energy as a stock rather than a flow. In order to normalize the above-mentioned situation, this article proposes a model to assess the average trophodynamic power ( P t ,avg : flow of eco-kinetic energy per space-time unit) of ecosystems by extrapolating the equation of average power for an oscillating string. With such a goal, we quantified the power associated to oscillations of the difference between the standardized values of species richness and evenness per value class of several species diversity distributions. In order to validate if P t , avg has a reliable meaning, P t , avg was correlated with a wide spectrum of biotic and abiotic environmental factors, every of them with a well-known independent meaning. We herein use field data from three databases (inland water zooplankton, leaf litter invertebrates, and ruderal vegetation) to test the reliability of this model. Our results showed that P t ,avg is correlated in a significant way, either positively or negatively, with important environmental factors. As a result, it is feasible to use the proposed equation as a reliable tool to measure the intensity of eco-kinetic energy flow under stationary and non-stationary conditions. This proposal has advantages in comparison with conventional methods (e.g.: standing biomass, carbon fixation), and it is useful for monitoring anthropogenic impacts on ecosystem metabolism. [ABSTRACT FROM AUTHOR]

The Darwinian interpretation (Di) of evolutionary process, and its subsequent development in the form of modern evolutionary synthesis (MES), plays a paradigmatic role in the mainstream biological thought. However, the main role in the improvement from Di to MES has depended on population genetics. Conventional ecosystem ecology has added relatively few specific insights to this endeavor in spite of the well-known combined selective influence from environment. This article integrates i ) recent findings in genetics (i.e.: evolutionary capacitance); ii ) orthodox topics as well as recent results from a large set of models in ecosystem ecology which have recently been encompassed under the term “organic biophysics of ecosystem”; and iii ) an epistemological analysis of the origin of On the Origin of Species … by reaching four main particular conclusions: ( a ) Despite the contemporary recognition that any kind of interspecific relationship has an evolutionary influence, the analytical emphasis of Di and MES on competition has been unwittingly oversized because of the paradoxical manner in which mutualism can emerge as an essential evolutionary force starting from competition, being this an unpublished topic that is analyzed in this manuscript by the first time. This link between two interspecific relationships that seem opposite to each other at the first glance is based on quantum effects that are totally unknown in conventional evolutionary theory due to its bias in favor of genetics, neglecting ecological considerations by contrast. ( b ) A holistic combination of ecological, genetic and evolutionary insights at the ecosystem level additionally confirms that the analytical role of evolutionary gradualism has also been oversized. ( c ) The main criterion of evolutionary success conventionally applied by Di and MES should be modified given that: ( d ) the preferential direction of evolutionary process theoretically proposed by Di and MES does not match with the direction of spontaneous development of natural ecosystems. The final section of this manuscript explains that these four critical outcomes in regard to Di and MES seem to have their root in epistemological inaccuracies involved in the origin of On the Origin of Species… that have been passed from generation to generation without being subjected to interdisciplinary scrutiny. This article showcases the need to review some of the foundational principles of Di and MES before building a “new floor” (i.e.: the extended evolutionary synthesis) supported on our current perspective about the evolutionary process. So, contrastingly with the genocentric nature of conventional evolutionary theory, large sections of our current evolutionary thought could change if we take into account some old results, as well as some recent ones, achieved by means of interdisciplinary approaches. In summary, this article concludes that the MES, despite its correct structure in essential points, could reach a significantly more complete epistemological condition than its current state if we add some fundamental results from ecosystem ecology that have been unwittingly neglected so far. [ABSTRACT FROM AUTHOR]

The influence of quantum ecological uncertainty (QEU: a discrete statistical trade-off between the standard deviations of species diversity and energy, two indicators that are essential to define the ecological niche of every species), has been proposed as a plausible explanation to the debate between the competitive exclusion principle (CEP) and the hypothesis of functional redundancy (HFR). The debate CEP ↔ HFR is a manifestation of the wide spectrum of issues connected with a very important problem in ecology: the so-called “biodiversity paradox” (i.e.: How is it possible that so many species can coexist despite the underlying influence of interspecific competition?). Any testable theoretical alternative to explain species coexistence depends on an accurate assessment of the ecological niche in practice. However, under QEU, the assessment of ecological niche cannot be as accurate as we want due to an objective limitation of nature: the above-mentioned trade-off. Consequently, it is nonsense following the debate about this topic in the conventional way; it is necessary to change our traditional point of view about this issue in order to develop a non-conventional interpretation of ecosystem functioning. However, QEU has been strongly criticized in a recently published article. This article is devoted to clarify certain misunderstandings whose nature is evident by reading the above-mentioned criticism and its precursory publications in comparison with the spectrum of articles that supports QEU. The general fulfillment of QEU has also been questioned by the above-mentioned criticism, so it is additionally supported in this article by a noticeably abbreviated inclusion of results from field data, surveyed under different circumstances in comparison with previous data, from two inland water taxocenes (zooplankton rotifers and crustaceans, Acton Lake, Ohio, U.S.A.) to which this model has not been applied so far. Our general conclusion is that the criticism to QEU has been groundlessly proposed due to epistemological inaccuracies; fragmentary understanding about the principles connected with QEU; as well as an incomplete literature review. [ABSTRACT FROM AUTHOR]

This article performs an analysis of the article in which Claude E. Shannon proposed his now famous H measure of information amount, by finding that four crucial traits analyzed by Shannon in regard to the meaning of H in information theory (i.e.: (a) introduction of a constant ad hoc – k – in order to achieve a formal connection between the statistical dimension of H and a given system of measurement units; (b) redundancy measurement; (c) joint events; and (d) conditional information) have strong theoretical connections with several important and well-known ecological phenomena (i.e.: (a′) extensive measurement of ecological entropy in quasi-physical units; (b′) theoretical meaning and successional behavior of redundancy; (c′) competitive exclusion; and (d′) ecological niche resilience, respectively). This set of corresponding connections (a, b, c, d, vs. a′, b′, c′, d′) has not been reported in the literature ever before, and it is fully understandable from the ecological viewpoint, despite the fact that the proposal from Shannon is previous and fully independent in comparison with any posterior attempt to establish a connection between ecology, physics and information theory. So, in practice, Shannon was also investigating in ecology and evolutionary biology, despite he was neither an ecologist nor an evolutionary biologist. In summary, our set of results: (i) implies that Shannon was an spontaneous ecologist, or at least an unwitting founder of ecological science such that, after Shannon, every ecologist of ecosystems can thus be viewed as a sort of “computer technician of nature”; (ii) highlights the fruitfulness of thinking about natural history in interdisciplinary terms; and (iii) expands the theoretical justification for applying H as a key indicator to build reliable models that are coherent with the principles of ecology, evolutionary biology, information theory and physics. [ABSTRACT FROM AUTHOR]

How complex systems are able to self-organize away from equilibrium and maintain their internal functional gradients over time, by adapting themselves and changing their own environment? This is one of the most interesting questions for contemporary ecology because of its potential usefulness to assess the ecological health of our natural environment by means of ecological monitoring. This article shows how a replacement and complementation of variables, that is very simple from the mathematical point of view, can be useful to transform the state equation previously developed to describe stationary ecological conditions into a state equation for non-stationary ecological conditions. The method applied was (a) empirically tested starting from field data collected from five surveys belonging to four different kinds of taxocenosis and (b) explained in a very brief and didactic way that can be easily understandable to everybody with a standard undergraduate training in ecological studies. The main result of this article is a simple mathematical equation that can be useful to perform an instantaneous assessment of the state and trend of ecosystem development in the short run starting from a single survey, that is to say, without the availability of long time series of data that allows the conventional studies of comparative ecology in order to assess the course of ecological succession. This proposal adds an innovative diagnostic tool empirically useful for ecological monitoring. [ABSTRACT FROM AUTHOR]

There has been a categorically unresolved crucial question in ecology and evolutionary theory for many decades; perhaps from the times of Charles Darwin himself: Is it possible, under natural conditions, that two species can perform a commonly shared ecological niche? There are two extreme conventional responses that have kept divided the scientific community in this regard for almost forty years: (a) No; that is to say, the well-known competitive exclusion principle (CEP). (b) Yes; that is to say, the well-known hypothesis of full functional redundancy (HFR). Obviously, the reliability of both responses depends on an underlying and even more essential requisite: that the ecological niche of a given species can be assessed with such accuracy as we could want in order to detect the degree in which it is shared between coexisting species. This article is the seventh in a continuous series of interconnected recent publications that promotes an alternative understanding of ecology and evolutionary biology which is in favor of strong and mutually fruitful analytical links between biology and physics. This article analyzes the statistical behavior of ecological niches by taking into account two indicators that are essential to perform the ecological niche of all species: species diversity per plot ( H p ) and eco-kinetic energy ( E e ) as a proxy for trophic energy in a scalar field H p , E e in which an oscillating performance of ecological niches is deployed. According to our results, in the same measurement in which the accuracy of H p assessments increases (reduction of H p 's standard deviation: σ H p ) the accuracy of E e assessment decreases (increment of σ E e ), and vice versa, in agreement with a pattern that is completely equivalent to that of the Heisenberg's uncertainty principle in quantum mechanics (i.e.: σ H p ⋅ σ E e ≫ 1 / 2 h e ec / 2 π ; where h e ec : ecological equivalent of Planck's constant found in previous publications). As a result, the ecological niche is, even in principle in addition to in practice, indeterminable with enough exactness to arrive to a categorical response to the above-stated question. This means that CEP and HFR are simultaneously true and false in the same measure, because the only feasible option to keep the functional stability of ecosystems is a wave-like combination of both options: when species are pushed to a high degree of coexistence (increase of partition of the gradient) in regard to H p values (a trend in favor of HFR), their degree of coexistence in regard to E e values diminishes (decrease of partition of the E e gradient, a trend in favor of CEP), and vice versa. The final sections of the article highlight the eco-evolutionary, biogeographical and socio-economic meaning of this result, by offering plausible alternative explanations to a wide spectrum of phenomena that appear to be only partially understood so far, e.g.: the contradictory results about the relationship between body size, species diversity and macroevolutionary rates; the general environmental scenario in favor of macroevolutionary leaps with a low probability to leave footprints in the fossil record; the unnecessary, although stimulant, influence of geographic isolation to promote evolutionary changes; the island rule; and the general meaning of the interaction between nature and society. [ABSTRACT FROM AUTHOR]

Abstract: Species coexistence has been a fundamental issue to understand ecosystem functioning since the beginnings of ecology as a science. The search of a reliable and all-encompassing explanation for this issue has become a complex goal with several apparently opposing trends. On the other side, seemingly unconnected with species coexistence, an ecological state equation based on the inverse correlation between an indicator of dispersal that fits gamma distribution and species diversity has been recently developed. This article explores two factors, whose effects are inconspicuous in such an equation at the first sight, that are used to develop an alternative general theoretical background in order to provide a better understanding of species coexistence. Our main outcomes are: (i) the fit of dispersal and diversity values to gamma distribution is an important factor that promotes species coexistence mainly due to the right-skewed character of gamma distribution; (ii) the opposite correlation between species diversity and dispersal implies that any increase of diversity is equivalent to a route of “ecological cooling” whose maximum limit should be constrained by the influence of the third law of thermodynamics; this is in agreement with the well-known asymptotic trend of diversity values in space and time; (iii) there are plausible empirical and theoretical ways to apply physical principles to explain important ecological processes; (iv) the gap between theoretical and empirical ecology in those cases where species diversity is paradoxically high could be narrowed by a wave model of species coexistence based on the concurrency of local equilibrium states. In such a model, competitive exclusion has a limited but indispensable role in harmonious coexistence with functional redundancy. We analyze several literature references as well as ecological and evolutionary examples that support our approach, reinforcing the meaning equivalence between important physical and ecological principles. [Copyright &y& Elsevier]

Highlights: [•] Twenty-nine ecological assemblages with 1649 plots from twelve kinds of taxocenes. [•] Direct correlation biomass↔diversity and inverse correlation dispersal↔diversity. [•] Biomass-dispersal trade-off (B-DT) under stationarity. [•] Coherence between B-DT, conventional ecology and the ecological state equation. [•] B-DT explains the core of the functional meaning of species diversity. [Copyright &y& Elsevier]

Rising sea-level following the Last Glacial Maximum lead to fragmentation of coastal limpet populations between islands of the Archipelago of Madeira. This fragmentation is reinforced by recent heavy exploitation reducing effective population size on Madeira Island. We use the limpet P. aspera to understand how the role of processes at different time scales (i.e. changes in the sea level and overexploitation) can influence the genetic composition of an extant species, relating these processes to reproductive phenology and seasonal shifts in ocean currents. Madeira Island, Porto Santo and Desertas (Archipelago of Madeira, NE Atlantic Ocean). The limpet Patella aspera. Twelve microsatellite genetic markers were used. A power analysis was used to evaluate the power of the microsatellite markers to detect a signal of population differentiation. Long-term past migrations were assessed using a Bayesian Markov Montecarlo approach in the software MIGRATE-n to estimate mutation-scaled migration rates (M = m / μ; m , probability of a lineage immigrating per generation; μ , mutation rate). Two scenarios were evaluated using an Approximate Bayesian Computation (ABC) in the software DIYABC 2.1 (i) Scenario 1: considered a population scenario from a reduced N e at time t 3 to a higher N e at time t 2 ; and (ii) Scenario 2 considering a reduction of N e from a time t 3 to a time t 2. Colonization of the archipelago by Portuguese settlers six centuries ago probably led to an important decrease in the genetic diversity of the species (N e). Contemporary gene flow strongly support a pattern of high asymmetric connectivity explained by the reproductive phenology of the species and spatio-temporal seasonal changes in the ocean currents. Spatio-temporal reconstructions using Bayesian methods, including coalescent and Approximate Bayesian Computation (ABC) approaches, suggest changes in the migration patterns from highly symmetric to highly asymmetric connectivity with subtle population differentiation as consequence of post-glacial maximum sea level rise during the Holocene. Our results suggest that anthropogenic activity could have had serious effects on the genetic diversity of heavily exploited littoral species since the end of the Pleistocene, probably accelerating in recent years. • Coastal limpet populations were affected by glaciations in the past. • Current limpet populations are highly affected by harvesting. • Genetic diversity is affected by human exploitation. • Local extinctions of limpet populations are expected due to human pressure. [ABSTRACT FROM AUTHOR]