In this project we will study how self-fertilization evolves and its evolutionary consequences in hermaphroditic animals . A strong limitation of the theory of mating system evolution is that it has been tested quasi exclusively in flowering plants. This poses problems of generality (to what extent do the arguments made depend on specificities of this group ?) and feasibility (most plants are not easily amenable to multi-generation experiments such as experimental evolution). For these two reasons it is urgent to develop animal models. We will here focus on a group of freshwater snails (basommatophorans) with highly diverse mating systems, presenting a suite of advantages making them ideal to address hitherto unsolved questions. We will focus on evolutionary transitions between outcrossing and selfing, how and when they occur, and their consequences. In particular we will test the long-standing hypothesis that selfing is an evolutionary dead-end in two ways. First we will characterize the number and unidirectionality of transitions in the phylogeny; second, we will empirically test the key steps of the most plausible scenario describing how an outcrossing species can become a preferential selfer (but not the reverse). The main components of this scenario are (i) constraints on mate or pollen availability resulting in a selection for selfing as a reproductive insurance. (ii) the existence of an intermediate state of preferential outcrossing with delayed, optional selfng when mates are lacking. (iii) the purging of inbreeding depression, resulting in runaway selection for selfing and even less inbreeding depression. (iv) the lack of adaptive potential in selfers, resulting in high extinction rates. All these aspects will be tested experimentally by looking at experimental evolution under elevated contraints on mating (frequent lack of mates), by measuring response to artificial and natural selection in pairs of outcrossing/selfing species living in the same environment, and by comparing their ability to colonize empty sites, estimated from metapopulation studies in the field This project is very ambitious in terms of (i) gathering molecular polymorphism data from many hitherto unstudied species, (ii) the number of size of experiments, and (iii) the requirement for long-term field data. It brings together a highly qualified consortium with previous experience of common work and complementary skills. Among the expected breakthroughs of this project will be the first experimental-evolution study of mating system evolution; and the first unbiased estimates of the frequency of mixed-mating in animals, and why it seems to be lower than in plants. All this will serve our ambition to establish animals, and especially basommatophoran snails, as essential models for mating system theory.

Coastal zones are complex social-ecological systems playing a crucial role in the economic, social and political development of many countries. However, they are amongst the areas of the world experiencing the highest rates of pressures (Jackson et al. 2001, Lotze et al. 2006). This concentration of uses has serious implications for their own sustainability (Adger et al. 2005). On the one hand, uses at the base of these economic activities can be negative drivers of changes within the linked coastal social-ecological systems, potentially impairing the goods and services provided through decreased resilience or resulting in conflicts among users. On the other hand, regional and global changes can threaten these uses by speeding up the crossing of tipping points. In addition, these direct and indirect processes can interact and result in multiplicative negative effects. Recently, some studies showed the potential of multiple-use areas (PPAs) to sustain high rates of uses (Claudet et al. 2010) and economic revenues (Claudet and Guidetti 2010, Guidetti and Claudet 2010), and buffer against human-induced pressures (Claudet et al. 2011). PPAs can therefore increase the social and ecological resilience of coastal systems. However, contrary to fully protected areas (FPAs; no uses allowed), PPAs can be highly different one from the other. Therefore, it was difficult from single PPAs to generalize the specific ecological and social drivers leading to such increased resilience, and the combined types and magnitude of uses they can buffer against are still very poorly understood. Addressing these questions are relevant and timely since European and associated countries are committed through European and international agreements to protect increased fractions of their coastlines and since PPAs are almost systematically favored at the expense FPAs (because accompanied by greater social acceptability). Within BUFFER, our main objective is the identification of the drivers of resilience in PPAs in order to sustain, adapt or transform derived goods and services necessary for human welfare in a context of multiple pressures. This objective will be addressed through the following questions: (1) Do PPAs help to buffer against human-induced functional changes in coastal assemblages (in relation to functional redundancy and resilience thresholds)? (2) Do PPAs help to buffer against human-induced selection pressures and in protecting phenotypic diversity (in relation to adaptations to future environmental change)? (3) Are uses and users less vulnerable in PPAs? Do PPAs provide new opportunities for users (in relation to adaptability and transformability of uses)? (4) Can global threats be more easily managed in PPAs compared to outside areas? (5) What are the context-dependent drivers of PPA resilience? To address these questions, our study cases are marine and freshwater PPAs across Europe, spanning across different ecological systems and various socio-cultural contexts in order to increase the robustness, generalization, applicability and transferability to decision-makers of our results. Our final goal is the identification and integration of indicators of coupled social-ecological resilience as tools for decision-making within the framework of better governance of policies and management of multiple uses in coastal areas.

REEFLUX builds upon recent and independent research by the team members on the evolution of coral reef structure and functioning. Despite using different approaches, our research consistently suggests a potentially key role of crypto-benthic fish assemblages in supporting the productivity of coral reef ecosystem. Specifically, we posit that the ability of crypto-benthic fishes to efficiently utilize microscopic resources, along with their life-history characteristics, make these taxa a true catalyzer of the trophic dynamics on coral reefs. This would help explaining the high productivity of coral reef system despite their oligotrophic environment. However, crypto-benthic fish fauna strongly depends on the structural complexity of the coral habitat and this structural complexity is presently at risk. Climate-induced coral bleaching produced in 2016 the most distructive global event on record, and for the first time such event is repeating itself for the second year in a row (2017). Future coral reefs will likely be subjected to annual die-off of corals while the ecological consequences of this phenomenon are still largely unknown. If our hypothesis is correct, one of the main source of coral reef food-webs is severely at risk. This would imply that the energy flow reaching large commercial fish species that sustain coastal human population may be severely impacted. REEFLUX aims at building the most detailed food-web for a marine ecosystem using next-generation techniques (i.e. metabarcoding, stable isotopes and compound-specific stable isotopes). Then, we will collect ecological information on the metabolic needs of species and quantify how these needs relate to their food intake. Using field experiments and mesocosms we will study the relationship between crypto-benthic assemblages and climate-induced habitat destruction. Using modeling and simulations informed by field data and experiments we will then test and quantify changes in energy fluxes and productivity of coral reef system according to climate-induced habitat loss.

Preserving marine biodiversity whilst maintaining the provisioning, cultural and regulating ecosystem services associated with marine fisheries in a context of global changes is a key challenge. While the need for Ecosystem Based Fisheries Management (EBFM), to ensure fisheries sustainability and resilience, is widely accepted, ecosystem-based approaches are still not operational for the management of European fisheries. SEASIDE will develop an innovative set of socio-ecosystem modeling, evaluating and projective tools to implement the next generation EBFM. Combining a participatory approach, Eco-Viability Analysis with the use of Models of Intermediate Complexity, SEASIDE will provide an integrated and transdisciplinary decision-support approach, enriching the evidence base and the transfer of science into advice. We will account for the multi-species, multi-trophic, multi-sector, dynamic and uncertain nature of fisheries systems, as well as the tradeoffs between the multiple ecological, economic and social objectives underpinning EBFM. We will identify and compare eco-viable management strategies in eight contrasting case studies ranging from the Arctic through temperate to tropical seas. We will draw on the multidisciplinary expertise in ecology, social sciences, modelling and participatory research of 26 academic and non-academic partners from 12 countries and including JRC, ICES, FAO and WWF. We will integrate this work within both existing regional advisory bodies, and relevant local stakeholder arenas, to bridge the gap between knowledge on the dynamics of marine social-ecological systems and EBFM. SEASIDE will effectively disseminate the project methodological, modeling and quantitative results via the production of generic software, data sets and evaluations, as well as guidelines adapted to the needs of stakeholders at multiple spatial scales. SEASIDE outputs will thus help improve policy coherence and implementation for sustainable European fisheries.

The though of coral reefs conjures up visions of a wide variety of colourful organisms living in clear, warm and shallow waters; but this is only the « tip of an iceberg », mainly from the surface to 30m depth. Compared to shallow reefs, what is below 30m, the so-called Mesophotic Coral Ecosystems (MCEs), characterized by the presence of light-dependant corals, remain quite a mystery. The legal and logistical constrains to access the MCEs are the most important hurdles that researchers are currently facing, which explained that 2/3 of MCEs remains understudied and their poor state of conservation. MCE and shallow reefs share some similarities, playing a key role in ecosystem services and goods, and being build around a keystone species: corals. The main difference is that we know far more on shallow reefs, than we do on MCEs. However the last years scientists and managers began to realize the importance of MCEs due to the fact that on coral reefs, the impacts of human and natural perturbations typically diminish with depth and distance from shore. It has been hypothesized that deep reefs serve as refuge for shallow reef habitats, but only tested in a few locations for few species. Today corals face growing risks in the Anthropocene epoch and will likely be the first victims of accelerating pace of environmental change, causing local to regional extinctions. So it is timely to expand coral research to these yet unexplored depths to unravel unknown biodiversity and identify areas that may be key players in the resilience of decimated shallow reefs. Depth is a critical challenge for research in MCEs. So to open up unexplored MCEs to scientists in the Pacific, DEEPHOPE will benefit from a unique partnership with “Under the Pole Expedition” (UTP) team, that will provide the cutting edge diving technology (with experimented deep divers), the availability of remotely operated vehicles and access to the boat “Why” to explore French Polynesia MCEs for 10 months. Around this partnership and to bring to lights the existence of MCEs, we build an interdisciplinary and international consortium of 12 scientists from 4 countries with strongly transverse competences (microbiology, physiology & ecology as well as acidification, sounds, and oceanography) to combine their efforts and address several critical goals relevant to MCEs: (1) Identify MCEs in French Polynesia and assess their coral diversity and abundance; (2) Evaluate the contribution of MCEs to the replenishment of threatened coral populations in shallow reefs; and (3) get new insights into the coral adaptation and/or acclimatization to deep environments. Despite MCE coordinated programmes were initiated the last few years in some countries; presently, France lags well behind the above mentioned teams in terms of studies dealing with MCEs (with only two papers published on MCEs from French overseas territory), despite France ranks third on a world-wide basis in terms of total surface area of its coral reefs. Hence, France has a responsibility to act for the sustainable conservation of MCEs and DEEPHOPE is the only-of-its kind scientific project dedicated to the study of MCEs in one of the French overseas territories. People care for what they know and the MCE is one of Earth’s last unknown prolific habitat types, thus hitherto condemned to society disregard. By exploring an under-exploited ecological areas to this day, we will fill in important scientific knowledge gaps and respond to a big societal challenge defined by ANR, which is how to sustainably manage the resources and adapt to climate change. Enhancing protection and resilience of coral reefs on Earth is a major challenge of our time for all societies all over the world and DEEPHOPE represents a unique opportunity to undertake cutting-edge research on MCEs with global significance, that will hopefully, convince of the needs to protect reefs as a whole, and not only the first 30m.