La conservación de la biodiversidad: hacia una estructura ecológica de soporte de la nación colombiana

El artículo parte del reconocimiento de la diversidad étnica y sus posibles relaciones con la mega diversidad biológica colombiana, cuya situación actual -de los ecosistemas, suelos y aguas- es también el resultado de una larga historia geológica y de pr

Guayabero i: un sitio precerámico de la localidad angostura ii, san josé del guaviare

La excavación arqueológica en el abrigo rocoso Guayabero I, considerada como la primera investigación estratificada de un sitio precerámico en la Amazonia Colombiana, registra la presencia del hombre prehistórico a partir de c.a. 7000 A.P. Las lascas prismáticas, concoidales, triangulares y retocadas; y en menor frecuencia los raspadores circulares, discoidales y laterales, todos instrumentos de tipo Abriense recuperados de una capa de suelo arenoso pardusco, son evidencia de una ocupación precerámica en el sitio entre el 5000 y 2000 A.P. La reducida muestra de fragmentos cerámicos encontrados en los niveles más superficiales de la excavación, por su similaridad, recuerda las tradiciones cerámicas encontradas en las localidades de Araracuara y La Pedrera (región Amazónica). Muestras de polen, y análisis de semillas, ocre y resinas ampliarán esta primera evidencia de cazadores -recolectores en la región tropical de la Amazonia Colombiana.Archaeological excavation at the Guayabero I rock-shelter, considered the first stratified investigation of the preceramic period in the Colombian Amazonia, reveals human presence since c. a. 7000 B.P.  in the region. The Abrian type prismatic, concoid, triangular and retouched flakes, and the less abundant, terminal, disk-like, lateral and circular scrapers recovered from a brownish sandy soil are evidence of a preceramic occupation between 5000 and 2000 B.P. Scarce ceramic fragments found at the uppermost levels of the excavation, due to their similarity, only suggest possible relationships to ceramic traditions of the Araracuara and La Pedrera localities, within the same Amazon region. Pollen, seeds, ochre, and resins analysis will probably expand this first evidence of hunter-gatherers in the eastern tropical lowlands of Colombia

Cambios ambientales y desarrollo cultural en el bajo río San Jorge

La depresión momposina, extensa hondonada al sur de las llanuras del Caribe, hoy poco poblada e inundada la mayor parte del año, estuvo densamente poblada en tiempos prehispánicos por los zenúes y sus antecesores, quienes construyeron una intrincada red de canales artificiales, en una extensión de más de 500.000 hectáreas de tierras cenagosas, desde Tierra Santa en el sur, hasta la desembocadura del San Jorge en el brazo de Loba del Magdalena (al norte), y, desde el límite de las sabanas al occidente, hasta el río Cauca (al oriente). En 1966, el geógrafo estadounidense James Persons, llamó la atención sobre la alteración del paisaje en la región del San Jorge, indicando que la mano humana era causante de ese rastrillado que podía observarse en las fotografías aéreas; estudió cuidadosamente su conformación e investigó las características físicas y geográficas de la zona. &nbsp

Landscape-scale drivers of glacial ecosystem change in the montane forests of the eastern Andean flank, Ecuador

Understanding the impact of landscape-scale disturbance events during the last glacial period is vital in accu- rately reconstructing the ecosystem dynamics of montane environments. Here, a sedimentary succession from the tropical montane cloud forest of the eastern Andean flank of Ecuador provides evidence of the role of non- climate drivers of vegetation change (volcanic events, fire regime and herbivory) during the late-Pleistocene. Multiproxy analysis (pollen, non-pollen palynomorphs, charcoal, geochemistry and carbon content) of the se- diments, radiocarbon dated to ca. 45–42 ka, provide a snap shot of the depositional environment, vegetation community and non-climate drivers of ecosystem dynamics. The geomorphology of the Vinillos study area, along with the organic‐carbon content, and aquatic remains suggest deposition took place near a valley floor in a swamp or shallow water environment. The pollen assemblage initially composed primarily of herbaceous types (Poaceae-Asteraceae-Solanaceae) is replaced by assemblages characterised by Andean forest taxa, (first Melastomataceae-Weinmannia-Ilex, and later, Alnus-Hedyosmum-Myrica). The pollen assemblages have no modern analogues in the tropical montane cloud forest of Ecuador. High micro-charcoal and rare macro-charcoal abundances co-occur with volcanic tephra deposits suggesting transportation from extra-local regions and that volcanic eruptions were an important source of ignition in the wider glacial landscape. The presence of the coprophilous fungi Sporormiella reveals the occurrence of herbivores in the glacial montane forest landscape. Pollen analysis indicates a stable regional vegetation community, with changes in vegetation population co- varying with large volcanic tephra deposits suggesting that the structure of glacial vegetation at Vinillos was driven by volcanic activity

Adaptation and Convergent Evolution within the Jamesonia-Eriosorus Complex in High-Elevation Biodiverse Andean Hotspots

The recent uplift of the tropical Andes (since the late Pliocene or early Pleistocene) provided extensive ecological opportunity for evolutionary radiations. We test for phylogenetic and morphological evidence of adaptive radiation and convergent evolution to novel habitats (exposed, high-altitude páramo habitats) in the Andean fern genera Jamesonia and Eriosorus. We construct time-calibrated phylogenies for the Jamesonia-Eriosorus clade. We then use recent phylogenetic comparative methods to test for evolutionary transitions among habitats, associations between habitat and leaf morphology, and ecologically driven variation in the rate of morphological evolution. Páramo species (Jamesonia) display morphological adaptations consistent with convergent evolution in response to the demands of a highly exposed environment but these adaptations are associated with microhabitat use rather than the páramo per se. Species that are associated with exposed microhabitats (including Jamesonia and Eriorsorus) are characterized by many but short pinnae per frond whereas species occupying sheltered microhabitats (primarily Eriosorus) have few but long pinnae per frond. Pinnae length declines more rapidly with altitude in sheltered species. Rates of speciation are significantly higher among páramo than non-páramo lineages supporting the hypothesis of adaptation and divergence in the unique Páramo biodiversity hotspot

Influence of the Amazon River on the Nd isotope composition of deep water in the western equatorial Atlantic during the Oligocene–Miocene transition

Dissolved and particulate neodymium (Nd) are mainly supplied to the oceans via rivers, dust, and release from marine sediments along continental margins. This process, together with the short oceanic residence time of Nd, gives rise to pronounced spatial gradients in oceanic 143Nd/144Nd ratios (εNd). However, we do not yet have a good understanding of the extent to which the influence of riverine point-source Nd supply can be distinguished from changes in mixing between different water masses in the marine geological record. This gap in knowledge is important to fill because there is growing awareness that major global climate transitions may be associated not only with changes in large-scale ocean water mass mixing, but also with important changes in continental hydroclimate and weathering. Here we present εNd data for fossilised fish teeth, planktonic foraminifera, and the Fe–Mn oxyhydroxide and detrital fractions of sediments recovered from Ocean Drilling Project (ODP) Site 926 on Ceara Rise, situated approximately 800 km from the mouth of the River Amazon. Our records span the Mi-1 glaciation event during the Oligocene–Miocene transition (OMT; ∼23 Ma). We compare our εNd records with data for ambient deep Atlantic northern and southern component waters to assess the influence of particulate input from the Amazon River on Nd in ancient deep waters at this site. εNd values for all of our fish teeth, foraminifera, and Fe–Mn oxyhydroxide samples are extremely unradiogenic (εNd ≈ −15); much lower than the εNd for deep waters of modern or Oligocene–Miocene age from the North Atlantic (εNd ≈ −10) and South Atlantic (εNd ≈ −8). This finding suggests that partial dissolution of detrital particulate material from the Amazon (εNd ≈ −18) strongly influences the εNd values of deep waters at Ceara Rise across the OMT. We conclude that terrestrially derived inputs of Nd can affect εNd values of deep water many hundreds of kilometres from source. Our results both underscore the need for care in reconstructing changes in large-scale oceanic water-mass mixing using sites proximal to major rivers, and highlight the potential of these marine archives for tracing changes in continental hydroclimate and weathering

Recreational sea fishing in Europe in a global contextParticipation rates, fishing effort, expenditure, and implications for monitoring and assessment

Marine recreational fishing (MRF) is a high-participation activity with large economic value and social benefits globally, and it impacts on some fish stocks. Although reporting MRF catches is a European Union legislative requirement, estimates are only available for some countries. Here, data on numbers of fishers, participation rates, days fished, expenditures, and catches of two widely targeted species were synthesized to provide European estimates of MRF and placed in the global context. Uncertainty assessment was not possible due to incomplete knowledge of error distributions; instead, a semi-quantitative bias assessment was made. There were an estimated 8.7 million European recreational sea fishers corresponding to a participation rate of 1.6%. An estimated 77.6 million days were fished, and expenditure was Euro5.9 billion annually. There were higher participation, numbers of fishers, days fished and expenditure in the Atlantic than the Mediterranean, but the Mediterranean estimates were generally less robust. Comparisons with other regions showed that European MRF participation rates and expenditure were in the mid-range, with higher participation in Oceania and the United States, higher expenditure in the United States, and lower participation and expenditure in South America and Africa. For both northern European sea bass (Dicentrarchus labrax, Moronidae) and western Baltic cod (Gadus morhua, Gadidae) stocks, MRF represented 27% of the total removals. This study highlights the importance of MRF and the need for bespoke, regular and statistically sound data collection to underpin European fisheries management. Solutions are proposed for future MRF data collection in Europe and other regions to support sustainable fisheries management.Institut Francais de Recherche pour l'Exploitation de la Mer; French Ministry of Fisheries Management; Greek National Data Collection Programme; European Commission, Data Collection Framework; Department for Environment, Food and Rural Affairs [MF1221, MF1230, MI001]; Norges Forskningsrad [267808]; State Department of Agriculture, Food Security and Fisheries Mecklenburg-Western Pomerania; Interreg IVa 2 Seas; Dutch Ministry of Economic Affairs; European Fishery Fund; Government of Galicia [ED481B2014/034-0

Phylogenetic Analysis of Seven WRKY Genes across the Palm Subtribe Attaleinae (Arecaceae) Identifies Syagrus as Sister Group of the Coconut

BACKGROUND:The Cocoseae is one of 13 tribes of Arecaceae subfam. Arecoideae, and contains a number of palms with significant economic importance, including the monotypic and pantropical Cocos nucifera L., the coconut, the origins of which have been one of the "abominable mysteries" of palm systematics for decades. Previous studies with predominantly plastid genes weakly supported American ancestry for the coconut but ambiguous sister relationships. In this paper, we use multiple single copy nuclear loci to address the phylogeny of the Cocoseae subtribe Attaleinae, and resolve the closest extant relative of the coconut. METHODOLOGY/PRINCIPAL FINDINGS:We present the results of combined analysis of DNA sequences of seven WRKY transcription factor loci across 72 samples of Arecaceae tribe Cocoseae subtribe Attaleinae, representing all genera classified within the subtribe, and three outgroup taxa with maximum parsimony, maximum likelihood, and Bayesian approaches, producing highly congruent and well-resolved trees that robustly identify the genus Syagrus as sister to Cocos and resolve novel and well-supported relationships among the other genera of the Attaleinae. We also address incongruence among the gene trees with gene tree reconciliation analysis, and assign estimated ages to the nodes of our tree. CONCLUSIONS/SIGNIFICANCE:This study represents the as yet most extensive phylogenetic analyses of Cocoseae subtribe Attaleinae. We present a well-resolved and supported phylogeny of the subtribe that robustly indicates a sister relationship between Cocos and Syagrus. This is not only of biogeographic interest, but will also open fruitful avenues of inquiry regarding evolution of functional genes useful for crop improvement. Establishment of two major clades of American Attaleinae occurred in the Oligocene (ca. 37 MYBP) in Eastern Brazil. The divergence of Cocos from Syagrus is estimated at 35 MYBP. The biogeographic and morphological congruence that we see for clades resolved in the Attaleinae suggests that WRKY loci are informative markers for investigating the phylogenetic relationships of the palm family