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As a novel endeavour in ecological science, this book focuses on a major issue in organismal life on Earth:species coexistence. The book crosses the usual disciplinary boundaries between palaeobiology, ecology and evolutionary biology and provides a timely overview of the patterns and processes of species diversity and coexistence on a range of spatio-temporal scales. In this unique synthesis, the author offers a critical and penetrating examination of the concepts and models of coexistence and community structure, thus making a valuable contribution to the field of community ecology. There is

Portugal is one of the few European Union countries that experience the "coexistence" of a coexistence legal framework with a regular coexistence practice. Since 2005, Bt maize crops have been grown in different regions -- either in small or large farms -- in compliance with a law that envisages coexistence procedures for either individual farmers or groups of farmers that agree to establish the so called "production zones." The monitoring of Bt maize crops is annually run and reported by the Ministry of Agriculture. Here we report on the first quinquennium of coexistence in Portugal, bearing down on regional distribution and evolution, farm sizes, coexistence measures, GM farmers' profile and their assessment of Bt crops and coexistence rules, and Bt maize destination. Opportunities and constraints are also pointed out.

Este artículo contiene 8 páginas, 6 figuras, 1 tabla. ; Interactions among species are essential in shaping ecological communities, although it is not always clear under what conditions they can persist when the number of species involved is higher than two. Here we describe a three-species assemblage involving the seagrass Cymodocea nodosa, the pen shell Pinna nobilis and the herbivore sea urchin Paracentrotus lividus, and we explore the mechanisms allowing its persistence through field obser vations and manipulative experiments. The abundance of pen shells was higher in seagrass beds than in bare sand, suggesting a recruitment facilitation. The presence of sea urchins, almost exclusively attached or around pen shells, indicated habitat facilitation for sea urchins, which overgrazed the meadow around the pen shells forming seagrass-free halos. Our results suggest that this system persists thanks to: (i) the behavioral reluctance of sea urchins to move far from pen shells, making their impact on seagrass strictly local, (ii) the sparse distri bution of pen shells and (iii) the plant's resistance mechanisms to herbivory. Unpacking these mechanisms allows a better understanding of how ecological communities are assembled. ; This study received financial support from the Spanish Government (project UM BRAL CTM2017-86695-C3-1R; CTM2017-86695-C3-3R). The Spanish National Research Council supported R. Arthur's visitorship with the Memorandum of Understanding between CEAB-NCF. ; Peer reviewed

4 páginas, 1 figura. ; The research conducted by the authors is supported by the Spanish Government projects CGL2006-04025 ⁄BOS, CGC2010-17172 and Consolider Ingenio Montes (CSD2008-00040), by the European project NEU NITROEUROPE (GOCE017841), and by the Catalan Government project SGR 2009-458. ; Peer reviewed

44 páginas.- 4 figuras.- 2 tablas.- 51 referencias.- Supplementary Information accompanies this paper at https://doi.org/10.1038/s41467-019-10453-0.- Estimation of species demographic parameters and pairwise competitive coefficients for both climatic treatments are available at Dryad Digital Repository https://doi.org/ 10.5061/dryad.5d1s952. Average species means for the 19 functional traits included in this experiment are included in Supplementary Table 1. ; Functional traits are expected to modulate plant competitive dynamics. However, how traits and their plasticity in response to contrasting environments connect with the mechanisms determining species coexistence remains poorly understood. Here, we couple field experiments under two contrasting climatic conditions to a plant population model describing competitive dynamics between 10 annual plant species in order to evaluate how 19 functional traits, covering physiological, morphological and reproductive characteristics, are associated with species¿ niche and fitness differences. We find a rich diversity of univariate and multidimensional associations, which highlight the primary role of traits related to water- and light-use-efficiency for modulating the determinants of competitive outcomes. Importantly, such traits and their plasticity promote species coexistence across climatic conditions by enhancing stabilizing niche differences and by generating competitive trade-offs between species. Our study represents a significant advance showing how leading dimensions of plant function connect to the mechanisms determining the maintenance of biodiversity. ; Funding support to conduct the experiment was provided by the Spanish Ecological Terrestrial Society (AEET, Jóvenes Investigadores grant 2014/2). I.M. P.-R. and L.M. were funded by a "Ramón & Cajal" contract (RYC-2013-13937) and an "Acción 6 UJA" fellowship (EI_RNM4_2017), respectively. O.G. acknowledges postdoctoral financial support provided by the European Union Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement (No. 661118-BioFUNC). I.M.P.-R. and L.G.-A. also thank support from the MICINN projects DECAFUN (CGL2015-70123-R) and INTERCAPA (CGL-2014-56739-R).

11 páginas.- 4 figuras.- 2 tablas.-- 44 referencias.- Supplementary Information accompanies this paper at https://doi.org/10.1038/s41467-019-10453-0 .- Data availability Estimation of species demographic parameters and pairwise competitive coefficients for both climatic treatments are available at Dryad Digital Repository https://doi.org/10.5061/dryad.5d1s952. Average species means for the 19 functional traits included in this experiment are included in Supplementary Table 1. ; Functional traits are expected to modulate plant competitive dynamics. However, how traits and their plasticity in response to contrasting environments connect with the mechanisms determining species coexistence remains poorly understood. Here, we couple field experiments under two contrasting climatic conditions to a plant population model describing competitive dynamics between 10 annual plant species in order to evaluate how 19 functional traits, covering physiological, morphological and reproductive characteristics, are associated with species' niche and fitness differences. We find a rich diversity of univariate and multidimensional associations, which highlight the primary role of traits related to water- and light-use-efficiency for modulating the determinants of competitive outcomes. Importantly, such traits and their plasticity promote species coexistence across climatic conditions by enhancing stabilizing niche differences and by generating competitive trade-offs between species. Our study represents a significant advance showing how leading dimensions of plant function connect to the mechanisms determining the maintenance of biodiversity. ; Funding support to conduct the experiment was provided by the Spanish Ecological Terrestrial Society (AEET, Jóvenes Investigadores grant 2014/2). I.M. P.-R. and L.M. were funded by a "Ramón & Cajal" contract (RYC-2013-13937) and an "Acción 6 UJA" fellowship (EI_RNM4_2017), respectively. O.G. acknowledges postdoctoral financial support provided by the European Union Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement (No. 661118-BioFUNC). I.M.P.-R. and L.G.-A. also thank support from the MICINN projects DECAFUN (CGL2015-70123-R) and INTERCAPA (CGL-2014-56739-R). ; Peer reviewed

In this study, we investigated the mechanisms behind species coexistence and the relationships between functional diversity and species richness in ant assemblages in both forest and pasture habitats in the southwestern Brazilian Amazon. We addressed the specific question: What is the primary mechanism for species coexistence in forest and pasture habitats? According to the identified mechanism in each habitat, we had the following alternative expectations: (i) niche partitioning – we expected to observe a linear positive relationship between functional diversity and species richness, indicating a complementary relationship; or (ii) niche filtering – a positive constant asymptotic relation between functional diversity and species richness, indicating a functional redundancy relationship. In total, we sampled 91 ant species, 82 species in a forest habitat and 16, in a pasture habitat. In the forest habitat we identified niche filtering as the structuring mechanism of the ant assemblage, but we were unable to identify a clear mechanism in the pasture habitat. Although the relationship between functional diversity and species richness was positive in both habitats, the relationship was weaker in the forest habitat, indicating a greater functional redundancy among the ant species in this habitat. Our results reinforce the divergence of species coexistence mechanisms and ant assemblage structures in both natural and human-modified habitats in the Southwestern Brazilian Amazon.

"A comprehensive framework for understanding species coexistence is the central concept in community ecology, but an understanding of this concept requires that we study the actual mechanisms of species interactions. Coexistence in Ecology examines the major features of these mechanisms for species that coexist at different positions in complex food webs and derives empirical tests from model predictions.Mark McPeek explores the various challenges species face by systematically building a model food web, beginning with an ecosystem devoid of life and then adding one species at a time. With the introduction of each new species, he evaluates the properties it must possess to invade a community and quantifies the changes in the abundances of other species that result from a successful invasion. McPeek continues this process until he achieves a multi-trophic level food web with many species coexisting at each trophic level, from omnivores, mutualists, and pathogens to herbivores, carnivores, and basic plants. He then describes the observational and experimental empirical studies that can test the theoretical predictions resulting from the model analyses.Synthesizing decades of theoretical research in community ecology, Coexistence in Ecology offers new perspectives on how to develop an empirical program of study rooted in the natural histories of species and the mechanisms by which they actually interact with one another"--

Sustainable (no trend in the abundance of interacting species) coexistence of species can be maintained due to fluctuations in their abundance and distribution over habitats in a heterogeneous environment. In the water shrew and the common shrew, joint settlements exist in near-water areas and occasionally appear in "dry" habitats, where the water shrew periodically invades. Given the well-known overlapping food niches of these species, one would expect the discovery of mechanisms that reduce competition, however, in "dry" habitats, we did not find such mechanisms. The use of space is characterized by a random overlapping of the home ranges of animals. In the preference test (a container with an animal versus an empty container), individual repeatability of sociability was found in tests with a conspecific stimulator, but was absent in tests with a stimulant of another species. The presence of the water shrew (as a stimulant) in the behavioral test did not increase of anxiety of common shrews, but increased the thoroughness of exploration. The reaction of the water shrew to the common shrew was not found in interspecific tests. In the absence of specific adaptations aimed at the spatial segregation of animals, the coexistence of the water shrew and the common shrew is quite well explained by "fluctuation-dependent" models of coexistence.

What limits the geographic distribution of organisms? -- Populations cannot increase without limit -- Favorable and unfavorable habitats exist for every species -- Overexploited populations will collapse -- Plant and animal communities can recover from disturbances -- Communities can exist in several configurations -- Keystone species may be essential to the functioning of biological communities -- Natural systems are products of evolution -- Natural systems recycle essential materials -- Solar energy powers natural ecosystems -- Climates change, communities and ecosystems change -- Extinction is forever and species losses caused by humans are avoidable