Natural Selection of Independently Originated Life Clades

Life on Earth descends from a common ancestor. However, it is likely that there are other instances of life in the universe. If so, each abiogenesis event will have given rise to an independently originated life clade (IOLC), of which Earth-life is an example. In this paper, I argue that the set of all IOLCs in the universe forms a Darwinian population subject to natural selection, with more widely dispersed IOLCs being less likely to face extinction. As a result, we should expect that, over time, more planets will become inhabited by fewer, more successful IOLCs

Parásitos como marcadores biológicos para la identificación de stocks del besugo, Pagellus bogaraveo, en aguas portuguesas de Atlántico nordeste

In this study the following parasites were selected as biological tags for the identification of blackspot seabream (Pagellus bogaraveo) stocks in the northeast Atlantic: Diphterostomum vividum (Digenea: Zoogonidae), Anisakis simplex s.l., A. physeteris, Anisakis sp. PB-2010 (Nematoda: Anisakidae), and Bolbosoma sp. (Acanthocephala: Polymorphidae). These parasite species point to the existence of three blackspot seabream stocks in the northeast Atlantic: one in the Azores region (ICES Area X), one in continental Portuguese shelf/slope waters (ICES Area IXa), and one in the waters around Madeira (sub-area 1.2 of FAO 34, central-eastern Atlantic).En este estudio se seleccionaron especies de parásitos como marcadores biológicos para la identificación de las poblaciones de besugo (Pagellus bogaraveo) del Atlántico nordeste: Diphterostomum vividum (Digenea: Zoogonidae), Anisakis simplex s.l., A. physeteris, Anisakis sp. PB-2010 (Nematoda: Anisakidae), y Bolbosoma sp. (Acanthocephala: Polymorphidae). Estas especies de parásitos indican la existencia de tres poblaciones distintas de besugo en el Atlántico nordeste: una en la región de los Azores (ICES Zona X), otra en la plataforma/talud continental portugués (ICES Zona IXa), y una tercera en las aguas adyacentes a la isla de Madeira (Subzona 1.2 de la FAO 34, Atlántico centro-este)

Living Objects

This paper addresses the question ‘what is an organism?’. Extant theories of organismality only provide a partial answer because they do not include an account of composition on which an ontology of living entities can be based. Here we develop a new account of what organisms are, based on a naturalistic answer to the special composition question, the bound state view. We argue that physical structure, including the existence of a boundary, is essential for life, and that, therefore, organisms are a particular kind of composite physical object – living objects. The bound state account of composition explains how composite physical objects exist in the world, and the property ‘life’ distinguishes the subset of those objects which are organisms. Our view obviates the need for disjunctive accounts of composition for living and non-living entities, placing ‘organism’ within the context of a broader scientific ontology, while at the same time providing a clear criterion of organismality that can be used in adjudicating problematic cases of biological individuality

Physical Explanation and the Autonomy of Biology

It is often claimed that biology is autonomous from the physical sciences, but this is seldom made precise. This paper makes explicit, for the first time, five distinct ‘autonomy of biology’ theses. Three moderate theses concerning scientific status, methodological distinctness, and non-reducibility of biology to physics, are correct, and are nearly universally accepted. Two stronger theses concerning the exclusivity of biological explanation and irrelevance of physical laws, are shown to be false on the basis of two case studies of physical explanations of biological phenomena. Which scales and laws are explanatorily relevant for a particular phenomenon must be decided empirically

Pesca de pequeñas embarcaciones en Madeira: recreativa frente artesanal

Small-scale recreational and artisanal fisheries are popular activities in the Autonomous Region of Madeira, and to date no information is available on their impact on regional coastal ecosystems. Through fishers’ surveys and official registers of fish landings, we described and characterized these fisheries in Madeira, comparing artisanal and recreational fisheries. In 2017, artisanal boats landed 91 species in fishing ports, while recreational catches landed 58 species. The most frequent catches were Dentex gibbosus, Phycis phycis and Pagrus pagrus for artisanal fishery and P. pagrus, Serranus atricauda and Diplodus spp. for recreational fishery. Comparing the same techniques, artisanal fishery always showed higher catch per unit effort values than recreational boat fishery. Nevertheless, the low number of artisanal fishery boats in comparison with the recreational ones reflected the lower total landings of the artisanal fishery, which in 2017 were 62.3 t, compared with the 509.8 t estimated catches for the recreational fishery. Though the estimated recreational fishing data were based on surveys and thus subject to various biases, this activity seems to negatively affect coastal ecosystems and, together with artisanal fishing, exerts a combined pressure on targeted species. Improved legislation for both fisheries is essential for an appropriate management of resources.La pesca recreativa y artesanal a pequeña escala (small-scale fisheries - SSF) es una actividad común en la Región Autónoma de Madeira de la que hasta la fecha, no se dispone de información sobre su impacto en los ecosistemas costeros regionales. A través de encuestas a pescadores y los registros oficiales de descargas de las especies capturadas, fue posible describir y caracterizar esta modalidad de pesca en la región y comparando la pesca artesanal con la recreativa. En 2017, las embarcaciones artesanales registraron descargas de 91 especies diferentes, mientras que en las capturas recreativas se contabilizaron 58 especies. Las capturas más frecuentes fueron Dentex gibbosus, Phycis phycis y Pagrus pagrus para la pesca artesanal, y P. pagrus, Serranus atricauda y Diplodus spp. para la recreativa. Al comparar las mismas técnicas coincidentes en las dos modalidades de pesca, se observó que en la pesca artesanal siempre presentó valores de CPUE más altos que la recreativa embarcada. Aún así, debido al bajo número de embarcaciones artesanales, se observó que los valores anuales de descargas totales para esta pesquería, son mucho menores que los estimados para la pesca recreativa embarcada (en 2017 fueron de 62,3 t en pesca artesanal, mientras que lo estimado para la pesca recreativa fueron 509,8 t). A pesar de que los datos estimados de pesca recreativa se basaron en encuestas y, por lo tanto, están sujetos a varios sesgos, esta actividad parece que puede afectar a los ecosistemas costeros, que junto con la pesca artesanal, puede ejercer una presión importante sobre las especies objetivo. Adecuar la legislación en ambas pesquerías es fundamental para poder realizar una gestión adecuada de los recursos