Coevolution of exploiter specialization and victim mimicry can be cyclic and saltational

Darwin’s Principle of Divergence explains sympatric speciation as gradual and directional. Contradicting evidence suggests that species’ traits evolve saltationally. Here, we model coevolution in exploiter-victim systems. Victims (resource population) have heritable, mutable cue phenotypes with different levels of defense. Exploiters have heritable, mutable perceptual phenotypes. Our simulations reveal coevolution of victim mimicry and exploiter specialization in a saltational and reversible cycle. Evolution is gradual and directional only in the specialization phase of the cycle thereby implying that specialization itself is saltational in such systems. Once linked to assortative mating, exploiter specialization provides conditions for speciation

Selection against Accumulating Mutations in Niche-Preference Genes Can Drive Speciation

Our current understanding of sympatric speciation is that it occurs primarily through disruptive selection on ecological genes driven by competition, followed by reproductive isolation through reinforcement-like selection against inferior intermediates/heterozygotes. Our evolutionary model of selection on resource recognition and preference traits suggests a new mechanism for sympatric speciation. We find speciation can occur in three phases. First a polymorphism of functionally different phenotypes is established through evolution of specialization. On the gene level, regulatory functions have evolved in which some alleles are conditionally switched off (i.e. are silent). These alleles accumulate harmful mutations that potentially may be expressed in offspring through recombination. Second mating associated with resource preference invades because harmful mutations in parents are not expressed in the offspring when mating assortatively, thereby dividing the population into two pre-zygotically isolated resource-specialist lineages. Third, silent alleles that evolved in phase one now accumulate deleterious mutations over the following generations in a Bateson-Dobzhansky-Muller fashion, establishing a post-zygotic barrier to hybridization

Marine nature-based solutions: Where societal challenges and ecosystem requirements meet the potential of our oceans

Nature-Based Solutions (NbS), a concept introduced in the late 2000s, has developed rapidly during the last years and is now frequently appearing in a broad spectrum of policies developed within the European Union. Its role in marine policies and research programmes is however still limited, but is likely to increase as NbS are adopted as key terminology in both biodiversity strategies and the EU taxonomy for sustainable financing. This will enhance the need for scientific advisory institutions to provide evidence-based advice on potential impacts of various combinations of marine NbS. To facilitate a critical debate about the prospects and pitfalls related to the operationalisation of marine NbS in an EU context, this paper provides an analysis of core definitions, potential categories of marine NBS and a suite of case studies. Coastal waters, shelf and open oceans present multiple options for testing new and scaling up known NbS, which could support both environmental restoration simultaneously with addressing multiple societal challenges, paving the way for a new level of ecosystem-based management. However, as the acceptance of NbS types will depend on ecosystem state and thus history, it will be a significant task to consistently communicate why some solutions may count as a NbS in some areas, while not in others. To conclude, the paper therefore raises a set of research priorities and policy advice aimed at ensuring the successful advice and deployment of marine NBS in support of multiple societal goals

WORKSHOP ON GUIDELINES FOR MANAGEMENT STRATEGY EVALUATIONS (WKGMSE2)

The purpose of the meeting was to bring up to date the methodologies and technical specifications that should be incorporated in Management Strategy Evaluation (MSE) work in ICES. The workshop was tasked with reviewing recent methodological and practical MSE work conducted in ICES and around the world, as well as the guidelines provided by the 2013 ICES Workshop on Guidelines for Management Strategy Evaluations (WKGMSE). The Terms of Reference indicated that the revision should include all aspects involved in MSE, while paying specific attention to several issues that had been identified through ICES practice. The Terms of Reference also requested WKGMSE 2 to consider how best to disseminate the guidelines to experts within the ICES community and the need for training courses. The workshop addressed all its Terms of Reference. The main results of the workshop are the revised MSE guidelines, as well as recommendations in relation to the ICES criterion for defining a management strategy as precautionary and in relation to the evaluation and advice on rebuilding strategies.publishedVersio

Dynamics of mimicry evolution

Plus d'information Le programme proposé couvre un grand nombre de domaines depuis la biologie fondamentale et les sciences biomédicales jusqu’aux sciences de l’homme et de la société et aux nouvelles technologies, mais dans une perspective d’approches résolument pluridisciplinaires et interdisciplinaires. En rassemblant des capacités de la recherche dans ces différents domaines, il devient possible de traiter de manière transversale les grandes questions liées au vieillissement et à..