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[EN] Molluscs of Chella Bank and its surroundings were studied from 21 samples collected with a van Veen grab in the depth range 95-729 m. A total of 299 taxa were identified (77 live-taken), thus increasing by more than 95% the species of molluscs reported in the recently declared site of community importance “Sur de Almería–Seco de los Olivos”. Two of the species are new records to Spanish waters and one to the Alboran Sea. The high species richness observed could be related to the location, the hydrological characteristics and the topographical heterogeneity of the area within the Alboran Sea. Four significant groups of samples were discriminated through multivariate analysis of quantitative data of live-taken molluscs: (I) bathyal muddy bottoms with buried rhodoliths; (II) bathyal muddy bottoms with coral rubble; (III) bathyal hemipelagic muddy bottoms and (IV) bathyal sandy bottoms. Molluscs were more diverse on coral framework bottoms than on sedimentary bottoms around Chella Bank. Most of the live-taken species are widely distributed along the Atlantic and Mediterranean Sea, and a few are strictly Mediterranean. The most striking feature was the occurrence of two species with planktotrophic larval development for which Chella Bank is the sole recorded locality in the Mediterranean (Episcomitra angelesae and Mitrella templadoi) and which elsewhere extremely rare (Mathilda spp.)., [ES] Se estudiaron los moluscos del banco Chella y sus fondos adyacentes a partir de veintiuna muestras cogidas con draga Van Veen entre 95 y 729 m de profundidad. Un total de 299 taxones fueron identificados (77 vivos), incrementando en un 95% el total de moluscos citados en el reciente Lugar de Importancia Comunitaria “Sur de Almería-Seco de los Olivos”. Dos especies son nuevas citas para aguas españolas y una para el mar de Alborán. La elevada riqueza específica puede estar relacionada con la localización, las características hidrológicas y la heterogeneidad topográfica de esta zona situada dentro del mar de Alborán. Mediante análisis multivariantes usando datos cuantitativos de la taxocenosis se han diferenciado cuatro grupos de muestras: (I) fangos del batiales con rodolitos enterrados, (II) fangos batiales con restos de corales, (III) fangos hemipelágicos batiales, y (IV) arenas batiales. La mayor diversidad se encontró en los fondos con restos de corales, a diferencia de los fondos sedimentarios situados alrededor del banco Chella. La mayoría de las especies vivas están ampliamente distribuidas por el Atlántico y el Mediterráneo, y muy pocas son estrictamente mediterráneas. Cabe destacar la ocurrencia de algunas especies con desarrollo planctotrófico (Episcomitra angelesae, Mitrella templadoi) en el banco Chella como única localidad registrada en el Mediterráneo o especies extremadamente raras en otros lugares (Mathilda spp.).

Understanding the biogeography of species in space and time is essential for the development of evidence-based conservation and management plans. In this paper we propose a biogeographical spatial modelling approach based on the favourability function, and developed under a fuzzy logic framework, to unravel the historical biogeography of the two European wild rabbit subspecies, Oryctolagus cuniculus algirus (Oca) and Oryctolagus cuniculus cuniculus (Occ), in the Iberian Peninsula (IP). We first reviewed published and unpublished information (PhD theses, scientific papers, technical reports, etc.) on the occurrence of each rabbit subspecies throughout the IP. We compiled data from 201 Iberian rabbit populations and from genetic information of 4348 rabbits that was used to identify subspecies. Only populations in which all rabbits surveyed belonged to one subspecies were considered in the modelling procedure. We modelled rabbit subspecies' distribution separately for populations in which nuclear and mitochondrial DNA sequences were available. We employed a trend surface analysis developed by logistic regressions, which applied the favourability function and fuzzy logic operations. Using our approach we indentify the expansion cores from which both rabbit subspecies would have expanded after isolation during the last glaciations. Furthermore, we reveal the possible existence of a competitive exclusion zone between both rabbit subspecies that may have prevented their further expansion. Finally, our study shows that the Oca subspecies is distributed in north-western areas previously attributed to Occ. This assessment of the actual and historical distribution of each rabbit subspecies may allow more specific conservation interventions, as the two subspecies are not just genetically distinct but also ecologically and behaviourally different. Our methodological approach could be useful in unravelling the historical biogeography of other lesser-known species.

In biogeography the competitive exclusion principle (CEP) has been confirmed in some cases but not in others. This has fueled an unresolved debate between those advocating niche theory or the neutral theory in biodiversity and biogeography. We suggest that this situation mainly arises from the use of crisp logic, where the CEP is defined as either completely true or false. We propose the application of the fuzzy concepts of favorability (the degree to which environmental conditions are propitious for the occurrence of individual species) and favorableness (the degree to which environmental conditions are simultaneously favorable for competing species) to operationalize a fuzzy version of the CEP. Favorability was obtained by performing species distribution models applying favorability functions, while favorableness was derived from the application of the fuzzy intersection between the favorability for competing species. Then we plotted individual favorability values along the gradient of favorableness. Two potentially competing species would coexist in high-favorableness locations, as the demands of both species would be well fulfilled. In locations of low favorableness, the result would be either autecological exclusion of both species or autecological segregation, as abiotic conditions are unfavorable for at least one of the species. Competitive exclusion would occur at the intermediate stretch of the favorableness gradient, as the conditions would be good enough for persistence of each species separately but not enough for permanent coexistence. According to this theoretical framework, the observed probability that a location belongs to the intermediate favorableness area given that the two species co-occur in this location should be lower than expected according to the environmental probability models for the two species. We tested this prediction on published data about the distribution of pairs of native and introduced deer species in Great Britain, using a Ba

The evolutionary history of African hunter-gatherers holds key insights into modern human diversity. Here, we combine ethnographic and genetic data on Central African hunter-gatherers (CAHG) to show that their current distribution and density are explained by ecology rather than by a displacement to marginal habitats due to recent farming expansions, as commonly assumed. We also estimate the range of hunter-gatherer presence across Central Africa over the past 120,000 years using paleoclimatic reconstructions, which were statistically validated by our newly compiled dataset of dated archaeological sites. Finally, we show that genomic estimates of divergence times between CAHG groups match our ecological estimates of periods favoring population splits, and that recoveries of connectivity would have facilitated subsequent gene flow. Our results reveal that CAHG stem from a deep history of partially connected populations. This form of sociality allowed the coexistence of relatively large effective population sizes and local differentiation, with important implications for the evolution of genetic and cultural diversity in Homo sapiens. Significance We combined ethnographic, archaeological, genetic, and paleoclimatic data to model the dynamics of Central African hunter-gatherer populations over the past 120,000 years. We show, against common assumptions, that their distribution and density are explained by changing environments rather than by a displacement following recent farming expansions, and that they have maintained large population sizes and genetic diversity, despite fluctuations in niche availability. Our results provide insights into the evolution of genetic and cultural diversity in Homo sapiens.

Dengue is a viral disease transmitted by mosquitoes. The rapid spread of dengue could lead to a global pandemic, and so the geographical extent of this spread needs to be assessed and predicted. There are also reasons to suggest that transmission of dengue from non-human primates in tropical forest cycles is being underestimated. We investigate the fine-scale geographic changes in transmission risk since the late 20th century, and take into account for the first time the potential role that primate biogeography and sylvatic vectors play in increasing the disease transmission risk. We apply a biogeographic framework to the most recent global dataset of dengue cases. Temporally stratified models describing favorable areas for vector presence and for disease transmission are combined. Our models were validated for predictive capacity, and point to a significant broadening of vector presence in tropical and non-tropical areas globally. We show that dengue transmission is likely to spread to affected areas in China, Papua New Guinea, Australia, USA, Colombia, Venezuela, Madagascar, as well as to cities in Europe and Japan. These models also suggest that dengue transmission is likely to spread to regions where there are presently no or very few reports of occurrence. According to our results, sylvatic dengue cycles account for a small percentage of the global extent of the human case record, but could be increasing in relevance in Asia, Africa, and South America. The spatial distribution of factors favoring transmission risk in different regions of the world allows for distinct management strategies to be prepared.

A significant link between forest loss and fragmentation and outbreaks of Ebola virus disease (EVD) in humans has been documented. Deforestation may alter the natural circulation of viruses and change the composition, abundance, behaviour and possibly viral exposure of reservoir species. This in turn might increase contact between infected animals and humans. Fruit bats of the family Pteropodidae have been suspected as reservoirs of the Ebola virus. At present, the only evidence associating fruit bats with EVD is the presence of seropositive individuals in eight species and polymerase chain reaction-positive individuals in three of these. Our study investigates whether human activities can increase African fruit bat geographical ranges and whether this influence overlaps geographically with EVD outbreaks that, in turn, are favoured by deforestation. We use species observation records for the 20 fruit bat species found in favourable areas for the Ebola virus to determine factors affecting the bats' range inside the predicted Ebola virus area. We do this by employing a hypothetico-deductive approach based on favourability modelling. We show that the range of some fruit bat species is linked to human activities within the favourable areas for the Ebola virus. More specifically, the areas where human activities favour the presence of five fruit bat species overlap with the areas where EVD outbreaks in humans were themselves favoured by deforestation. These five species are as follows: Eidolon helvum, Epomops franqueti, Megaloglossus woermanni, Micropteropus pusillus and Rousettus aegyptiacus. Of these five, all but Megaloglossus woermanni have recorded seropositive individuals. For the remaining 15 bat species, we found no biogeographical support for the hypothesis that positive human influence on fruit bats could be associated with EVD outbreaks in deforested areas within the tropical forest biome in West and Central Africa. Our work is a useful first step allowing fur