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There is evidence for early Pleistocene Homo in northern Europe, a novel hominin habitat. Adaptations enabling this colonisation are intriguing given suggestions that Homo exhibits physiological and behavioural malleability associated with a ‘colonising niche’. Differences in body size/shape between conspecifics from different climates are well-known in mammals, could relatively flexible size/shape have been important to Homo adapting to cold habitats? If so, at what point did this evolutionary stragegy arise? To address these questions a base-line for adaptation to climate must be established by comparison with outgroups. We compare skeletons of Japanese macaques from four latitudes and find inter-group differences in postcranial and cranial size and shape. Very small body mass and cranial size in the Southern-most (island) population are most likely affected by insularity as well as ecogeographic scaling. Limb lengths and body breadths show group differences that accord with the expectations of thermoregulation across the whole range of latitudes. Postcranial size appears to vary more than shape, yet there is also evidence that limb segments follow Allen's rule in the forelimb at least, suggesting differing climatic signals in different regions of the skeleton. In contrast to other intraspecific studies of catarrhine ecogeography, the results presented here demonstrate non-allometric latitudinal patterns in craniofacial shape in Japanese macaques, which align closely with what is seen in cold-adapted humans. These insights begin to provide a comparison for hominin adaptation to similar habitat diversity and the role of biological adaptation in shaping the evolution and dispersal of Homo species.

Resumen El Río Presidio, ubicado en el sur de Sinaloa, México, pertenece a la zona de transición zoogeográfica NeárticoNeotropical, donde su fauna de peces podría manifestar cambios en la abundancia y distribución de las especies durante los períodos de lluvias y de secas. El objetivo principal de este estudio fue describir la composición taxonómica y la abundancia espacial y temporal de la fauna de peces de la parte baja y media del Río Presidio, mediante muestreos bimestrales de abril 2008 a febrero 2009. Cuarenta especies (39 nativas y 1 exótica) pertenecientes a 32 géneros y 19 familias fueron registradas, siendo las familias Gerreidae y Poeciliidae las más diversas con cinco y cuatro especies, respectivamente. Seis especies: Lile stolifera, Oreochromis aureus, Awaous banana, Gobiomorus maculatus, Anchoa analis y Atherinella crystallina, en ese orden de importancia contribuyeron con casi el 49 % de la abundancia íctica total. La riqueza de especies y la salinidad demostraron una relación directa y ambas tuvieron una relación inversa con la altitud. Con base en la disimilitud de especies entre sitios, dos tipos de ensambles de peces fueron distinguidos a través de un gradiente de salinidad y turbidez en el río, el primero representado por especies de derivación marina (periféricas) en la parte baja, y el segundo por especies dulceacuícolas secundarias en la parte media. La mayor similitud de especies se dio en agosto y septiembre y estuvo asociada a condiciones de altos flujos del periodo de lluvias. Veintisiete especies tienen afinidad a la Región del Pacífico oriental, seis a la Región Neotropical, dos a la Región Neártica (Dorosoma smithi e Ictalurus cf. pricei), una Anfiatlántica (Mugil curema), una Circumtropical (M. cephalus), dos Anfiamericanas (Agonostomus monticola y Gerres cinereus) y una exótica (O. aureus). Abstract The Rio Presidio in the southern Sinaloa, Mexico belongs to Nearctic-Neotropical zoogeographical transition zone, where its fish fauna could manifest changes in the abundance and distribution of the species during rainy and dry periods. The main objective of this study was to describe the taxonomic composition and spatial and temporal abundance of the fish fauna from the lower and middle Rio Presidio, by means of bimonthly samplings from April 2008 to February 2009. Forty fish species (39 native and 1 exotic) belonging to 32 genera and 19 families were registered. Two families (Gerreidae and Poeciliidae) contained the highest numbers of species (five and four, respectively). Six species (Lile stolifera, Oreochromis aureus, Awaous banana, Anchoa analis, Gobiomorus maculatus and Atherinella crystallina) in this order of importance contributed with almost 49 % of the total fish abundance. Species richness and salinity showed a direct relationship and an inverse relationship with the altitude. Based on the coefficient of similarity of species among sites two fish assemblages were identified. The first assemblage formed by species from marine derivation (peripheral) occurring in the lower part of the river, and the second assemblage by secondary freshwater species in the middle part. The higher fish species similarity observed in August and September was under the influence of the highest flows of the rainy period. Twenty-seven 27 species showed affinity to the Tropical Eastern Pacific Region, six species to the Neotropical region and two to the Nearctic region (Dorosoma smithi and Ictalurus cf. pricei ); one species has an Amphiatlantic distribution (Mugil curema), another is circumtropical (Mugil cephalus), two species have Amphiamerican distribution (A. monticola and G. cinereus), and one is exotic (O. aureus). Rev. Biol. Trop. 66(2): 848-862. Epub 2018 June 01.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES Skulls are complex morphological structures that exhibit phenotypic plasticity and adaptations to different functions and processes, and are under different pressures, such as the geographical or environmental ones. South America is a latitudinal broad continent, encompassing a variety of biomes and climatic conditions, revealing ecomorphological variations in many mammal species. The main objective of this study was to investigate ecogeographical patterns and determinant factors related to cranial variations in species and genera of mammals with wide geographic distribution in South America (Marsupialia, Xenarthra and Glires), based on size and shape data. From skull photographs of 1.017 specimens in the ventral view in scientific collections, geometric morphometric techniques were used to understand skull variation within the different groups. Two species of marsupials were studied in Chapter I, Caluromys philander and C. lanatus, which were similar in shape, showing similar phenotypic trajectories. The effect of size on shape (allometry) was important for C. lanatus, helping biomechanically in environments southern Amazonia. In addition, the two species were spatially structured, also showing great environmental influence (especially temperature), following the inverse of the Bergmann’s rule. In Chapter II, three species of the Xenarthra superorder (Bradypus variegatus, Tamandua tetradactyla, and Dasypus novemcinctus) presented a weak allometric influence. However, geographical (neutral) factors influenced the shape of B. variegatus and the size of T. tetradactyla, which could be a reflection of the low mobility and dispersion capacity of both species. Importantly, the environmental influence (niche) affected the three species, most notably B. variegatus (which follows the Bergmann’s rule), and D. novemcinctus (highly mobile species, being locally affected by the environment). Chapter III deals with the taxa Cuniculus paca, Hydrochoerus hydrochaeris, Nectomys spp., and Sylvilagus brasiliensis. Allometry was present notably for the genus Nectomys, suggesting an association with the sexual dimorphism found only in this genus. The environmental influence was noticeable for highly dispersive and large body size species, such as H. hydrochaeris and C. paca. These two species were also affected by spatial filters (geography), but to a lesser extent, as occurred for the other two taxa. Finally, Chapter IV addressed more specifically the masticatory apparatus (molar series and zygomatic arch) of the species of Rhipidomys and Nectomys genus. The interspecific distinction within each genus was visible for some species of Rhipidomys (size and shape), whereas the species of Nectomys presented weak disparity. In relation to the biogeographical hypotheses, the phenotypic response of each genus was divergent, with Rhipidomys shape being related to the primary productivity, and the Nectomys size related mainly to precipitation and temperature. These distinct results suggest different responses according to constraints and ecological attributes of each genus (specialist and generalist, respectively). In general, the results found in this study suggest that the response of each taxon to the various influences suffered is not necessarily the same, but depends on its characteristics and particularities that induce different cranial modifications. Os crânios são estruturas morfológicas complexas que apresentam plasticidade fenotípica e adaptações a diferentes funções e processos e estão sob diferentes pressões, como as geográficas ou ambientais. A América do Sul é um continente latitudinalmente amplo, abrangendo uma variedade de biomas e condições climáticas, revelando variações ecomorfológicas em muitas espécies de mamíferos. O principal objetivo deste estudo foi investigar padrões biogeográficos e fatores determinantes relacionados a variações cranianas em espécies e gêneros de mamíferos com ampla distribuição geográfica na América do Sul (Marsupialia, Xenarthra e Glires), com base em dados de tamanho e forma. A partir de fotografias cranianas de 1,017 espécimes na vista ventral em coleções científicas, técnicas de morfometria geométrica foram usadas para entender a variação do crânio nos diferentes grupos. Duas espécies de marsupiais foram estudadas no Capítulo I, Caluromys philander e C. lanatus, as quais foram semelhantes na forma, demonstrando trajetórias fenotípicas similares. O efeito do tamanho na forma (alometria) foi importante para C. lanatus, ajudando biomecanicamente em ambientes ao sul da Amazônia. Ainda, as duas espécies foram estruturadas espacialmente, além de demonstrarem grande influência ambiental (especialmente temperatura), seguindo o inverso a Regra de Bergmann. No Capítulo II, três espécies da superordem Xenarthra (Bradypus variegatus, Tamandua tetradactyla, e Dasypus novemcinctus) apresentaram uma fraca influência alométrica. Entretanto, fatores geográficos (neutros) influenciaram a forma de B. variegatus e o tamanho de T. tetradactyla, o que poderia ser um reflexo da baixa capacidade de mobilidade e dispersão de ambas as espécies. Mais importante, a influência ambiental (nicho) afetou as três espécies, com destaque para B. variegatus (seguindo a regra de Bergmann), e D. novemcinctus (espécie altamente móvel, sendo afetada localmente pelo ambiente). O Capítulo III trata da variação da forma dos táxons Cuniculus paca, Hydrochoerus hydrochaeris, Nectomys spp., e Sylvilagus brasiliensis. A alometria esteve presente notoriamente para o gênero Nectomys, sugerindo uma associação com o dimorfismo sexual encontrado apenas neste gênero. A influência ambiental foi perceptível para as espécies altamente dispersivas e com grande tamanho corporal, como H. hydrochaeris e C. paca. Essas duas espécies também foram afetadas pelos filtros espaciais (geografia), mas em menor grau, como ocorreu para os outros dois táxons. E por fim, o Capítulo IV abordou mais especificamente o aparato mastigatório (conjunto dos molares e arco zigomático) das espécies dos gêneros Rhipidomys e Nectomys. A distinção interespecífica dentro de cada gênero foi visível para algumas espécies de Rhipidomys (tamanho e forma), enquanto as espécies de Nectomys apresentaram fraca disparidade. Em relação às hipóteses biogeográficas, a resposta fenotípica de cada gênero foi divergente, com a forma de Rhipidomys relacionada com a produtividade primária, e o tamanho de Nectomys relacionado com a precipitação e temperatura. Esses resultados distintos sugerem respostas diferentes de acordo com restrições e atributos ecológicos de cada gênero (especialista e generalista respectivamente). De modo geral, os resultados encontrados neste estudo sugerem que a resposta de cada táxon frente às várias influências sofridas não é necessariamente a mesma, mas depende de suas características e particularidades que induzem a modificações cranianas distintas.

Background: Seed weight is a key fitness-related trait associated with plant adaptation and is commonly targeted in plantbreeding.Aims: We evaluated seed weight variation within and between Trichloris crinita and Trichloris pluriflora across theirgeographical ranges in Argentina.Methods: Genetic variation in seed weight was evaluated through a common garden experiment. To examine the possiblerole of such variation in local adaptation, we compared the seed weight of plants of populations raised in the commongarden with seed weight variation and ecogeographical variables across their original habitats. We also evaluatedexperimentally the effects of seed weight variation upon osmotic stress tolerance at germination.Results: Variation in seed weight existed in both species. Such variation had a genetic basis in T. crinita related to severalecogeographical variables. Larger seeds of T. crinita were associated with more stressful environments and producedlarger seedlings under both osmotic stress and non-stress conditions.Conclusions: Our results suggest that seed weight variation in T. crinita is likely adaptive, with large seed having anadvantage during early developmental stages, particularly under stressful conditions. Such knowledge should prove helpfulin selecting the most suitable populations for restoration and plant breeding. Fil: Marinoni, Lorena del Rosario. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Zabala, Juan Marcelo. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina Fil: Parra Quijano, Mauricio. Tratado internacional sobre los recursos Fitogenéticos para la Alimentción y la Agricultura; Italia Fil: Fernandez, Roberto Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Pensiero, Jose Francisco. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina

Genetic variability was studied in 78 populations of locally collected Vicia L. taxa for seed albumins, globulins and prolamins patterns by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) along with an ecogeographic characterization of sites investigated. 131, 119 and 98 bands were respectively used for albumin, globulin and prolamin cluster analysis. Dendrograms based on the Jaccard index and the UPGMA method were generated and the degree of genetic diversity between and within taxa was evaluated. Five clusters were generated from albumins, six from globulins and four from prolamins patterns. The results reflect the great diversity of storage proteins and a high correlation was obtained between the three studied fractions. Several accessions present specific bands which could be used as a discriminatory marker both on intra and interspecific levels. No clear relationships were seen between the groups according to their geographical origin. Data obtained from ecogeographic investigation can be used for future collecting missions.

portuguesLippia rotundifolia e uma especie nativa do Cerrado e endemica da Cadeia do Espinhaco. Devido a poucas informacoes acerca da especie, objetivou-se caracterizar as condicoes ecogeograficas e edafoclimaticas bem como os atributos fisico-quimicos do solo da Lippia rotundifolia no estado de Minas Gerais, Brasil. Realizou-se o levantamento ecogeografico em 13 locais (Parque Estadual Veredas do Peruacu, Gigante, Rio do Peixe, APA de Olhos d’Agua, Joaquim Felicio, Parque Estadual do Rio Preto, Sao Goncalo do Rio das Pedras, Rio Tigre, RPPN Brumas do Espinhaco, Lapinha, Poco Bonito, Aboboras e Parque Estadual de Serra Nova). Os resultados identificaram os ambientes pertencentes aos biomas Cerrado e Caatinga especificamente nos campos rupestres e de altitude. A especie ocorre entre as altitudes de 691 a 1311 metros, precipitacao entre 700 a 1600 milimetros e temperatura media variando entre 14,5 a 24 graus. Nestas fitofisionomias os solos apresentam textura arenosa, sao hiperdistrofico, altamente toxico com baixa capacidade de troca de cations, que faz a especie ser pouco exigente quanto aos fatores edafoclimaticos e ecogeograficos. Palavras-chave: recursos geneticos; caracterizacao; ecogeografia; Lippia rotundifolia EnglishLippia rotundifolia is a specie native to the Brazilian Cerrado, endemic to the Cadeia do Espinhaco mountain range. Due to the limited information about the species, the present study aimed to characterize the ecogeography, climate conditions and physical and chemical characteristics of the soil of Lippia rotundifolia in the state of Minas Gerais, Brazil. Thirteen sites were ecogeographically characterized: Parque Estadual Veredas do Peruacu; Gigante; Rio do Peixe; AEP of Olhos D’agua; Joaquim Felicio; Parque Estadual do Rio Preto; Sao Goncalo do Rio das Pedras; Rio Tigre; RPPN Brumas do Espinhaco; Lapinha; Poco Bonito; Aboboras; and Parque Estadual de Serra Nova. Environments belonged to Cerrado and Caatinga biomes, specifically in rocky and altitude fields. The species occurs at altitudes between 691-1311m, with precipitation between 700 to 1600mm and average temperature between 14.5 to 24°C. In these vegetation types, the soils were sandy, hyper dystrophic and highly toxic with a low cation exchange capacity. These characteristics make the species undemanding with regard to edaphoclimatic and ecogeographic factors. Key words: genetic resources; characterization; ecogeography; Lippia rotundifolia

We have recently argued that marine interfacial surface tension must have a distinctive biogeography because it is mediated by fresh surfactant macromolecules released locally through the food web. Here we begin the process of quantification for associated climate flux implications. A low dimensionality (planar) equation of state is invoked at the global scale as our main analysis tool. For the reader&rsquo, s convenience, fundamental surfactant physical chemistry principles are reviewed first, as they pertain to tangential forces that may alter oceanic eddy, ripple, and bubble fields. A model Prandtl (neutral) wind stress regime is defined for demonstration purposes. It is given the usual dependence on roughness, but then in turn on the tension reduction quantity known as surface pressure. This captures the main net influences of biology and detrital organics on global microlayer physics. Based on well-established surrogate species, tangent pressures are related to distributed ecodynamics as reflected by the current marine systems science knowledge base. Reductions to momentum and related heat-vapor exchange plus gas and salt transfer are estimated and placed on a coarse biogeographic grid. High primary production situations appear to strongly control all types of transfer, whether seasonally or regionally. Classic chemical oceanographic data on boundary state composition and behaviors are well reproduced, and there is a high degree of consistency with conventional micrometeorological wisdom. But although our initial best guesses are quite revealing, coordinated laboratory and field experiments will be required to confirm the broad hypotheses even partially. We note that if the concepts have large scale validity, they are super-Gaian. Biological control over key planetary climate-transfer modes may be accomplished through just a single rapidly renewed organic monolayer.

Aegilops geniculata Roth is an annual grass relative to cultivated wheats and is widely distributed in North Africa. In order to understand the diversity of this species, 14 populations collected in different bioclimatic areas in northern Algeria were analyzed using morphological and biochemical characters. Principal component analyses (PCA) based on the inflorescence characters and ecological parameters allowed the separation of populations in two mainly bioclimatic clusters characterized by different morphological patterns. Populations originated from humid and sub-humid coastal areas were characterized by vigorous spikes. Samples collected from intermediate and high mountains with humid and semi-arid conditions had long and lanceolate spikes. Individuals with small and narrow spikes were characteristics of steppic highlands in semi-arid conditions and high mountains with humid bioclimate. Individuals were distinguished successively by spike width, spike length, rachis length and awns number. Electrophoretic analyses of high molecular weight glutenin subunits (HMW-GS) based on the phenotypic variability and genetic distances revealed a significant variation within and between populations associated with bioclimatic conditions, in particular winter temperature. Genetic diversity was higher in populations growing under warm bioclimates than in those from cold bioclimates. These results suggest that a part of the variation for HMW glutenin variability is adaptive.

Kaz Mountain (Mt Ida), with an elevation of 1774 meters, is the highest landform on the Biga peninsula located in the northwest of Turkey. This mountainous area is situated on the transition zone between the Mediterranean and Black Sea climates. Thus, it has ecologically interesting features. The purpose of this study is to explain the ecogeographical features of the ecosystem of Kaz Mountain. To that end, all physical features such as geomorphological, geological, climate, soil, hydrographical, vegetation, and fauna features were examined. The data obtained was compiled and classified. Hence, ecogeographical features of the area were revealed. Some parts of Kaz mountains were previously declared a national park for the purpose of protection. However, the national park does not cover all of the mountainous mass. The population pressure on the area is constantly increasing. For this reason, national park boundaries should be expanded to protect the whole ecosystem.

14 pages, 4 figures, 6 tables, 56 references. Prof. H.J.B. Birks, A. Aparicio and two anonymous reviewers provided helpful comments. F.J. Salgueiro helped with computer design of map figures and J.M. Rubio advised compiling climatic data., [EN]: The geographic ranges of heath species in Europe and the Mediterranean and their relationships with environmental (climatic and ecogeographic) variables and biological features are analysed by means of multivariate methods. In particular, TWINSPAN classifications into floristic elements and floristic regions, DCA floristic ordinations, CCA environment-constrained ordinations and CCA biology-constrained ordinations are carried out. Results of the analyses show a correspondence with conventional regionalization analyses based on broader criteria, and less correspondence with numerical analyses of other taxonomic groups at a similar scale. This lack of fit depends on the particular history and ecology of the taxonomic groups under study. A number of climatic (temperature and water stress) and geographic (coast length) variables are associated with different types of heaths according to their geographical ranges (continental, Mediterranean, Atlantic). Biological features of heaths account for a small part of the variation in range, but the association of temperate heaths with a preference for acid soils, of Mediterranean heaths with pubescence, and of Atlantic heaths with plant height is of interest. Heath species richness throughout Europe and the Mediterranean is analysed by multiple regression analyses and, apart from a strong influence of area size, a significant effect of water conditions, temperature and proximity to sea is detected. The area with the highest heath species richness is Western Mediterranean. Additional classification, ordination and multiple regression analyses of heaths in the Iberian Peninsula (Spain and Portugal, the areas with the highest heath diversity) revealed similar patterns to those found in Europe and the Mediterranean. The effect of heterogeneity of the studied units at this latter scale is removed in the Iberian analysis because of the relative homogeneity of the units considered at this scale., [ES]: Se estudia la distribución geográfica de las especies de brezos en Europa y el Mediterráneo y sus relaciones con un conjunto de factores ambientales (climáticos y ecogeográficos) y rasgos biológicos por medio de métodos multivariantes. En particular, se llevan a cabo clasificaciones TWiNSPAN en elementos y regiones florísticas, ordenaciones florísticas (DCA) y ordenaciones restringidas por las características ambientales y los rasgos biológicos (CCA). Los resultados de estos análisis muestran una correspondencia alta con la regionalización convencional basada en varios criterios y una menor correspondencia con los análisis numéricos de otros grupos taxonómicos en un ámbito geográfico similar. Esta falta de correspondencia depende de la historia y ecología particulares de los grupos taxonómicos estudiados. Varias variables climáticas (temperatura y estrés hídrico) y geográficas (longitud de costa) están asociadas a tipos diferentes de brezos según su distribución geográfica (continental, mediterránea, atlántica). Los rasgos biológicos de los brezos explican una parte pequeña de la variación geográfica, pero debe resaltarse la asociación de los brezos templados con los suelos ácidos, de los brezos mediterráneos con la pubescencia y de los brezos atlánticos con el tamaño de la planta. La riqueza de especies de brezos en Europa y el Mediterráneo se analiza por medio de regresión múltiple y, aparte de un influencia fuerte del tamaño del área, se detecta un efecto significativo de las condiciones hídricas, la temperatura y la proximidad al mar. El área con mayor riqueza de especies de brezos es el oeste del Mediterráneo. Análisis adicionales de clasificación, ordenación y regresión múltiple de los brezos de la Península Ibérica (España y Portugal, las áreas con mayor diversidad de brezos) revelan patrones similares a los observados en Europa y el Mediterráneo. El efecto de la heterogeneidad de las unidades de área a esta última escala es eliminado en el análisis ibérico dada la relativa homogeneidad de las unidades de éste., Most of the research was funded by National Geographic Society (4474-91) and DGICYT (PB91-0894) grants.

International audience; The button mushroom Agaricus bisporus commercially cultivated requires 16-19 degrees C during the fruiting period. Wild strains are also present in natural habitat, and in light of their wide range of geographic distribution reported, from boreal region to tropical region, questions on the development adaptation to temperature arose. Isolates from various geographic areas were screened for their ability to fruit at higher temperature (FHT ability) than commercial cultivars. The FHT trait discriminated at the varietal rank. Agaricus bisporus var. eurotetrasporus was unable to develop any sporophores whilst A. bisporus var. burnettii adapted perfectly to 25 degrees C for fruiting, suggesting that the FHT ability is a fixed trait in these varieties. In contrast, FHT ability of A. bisporus var. bisporus appeared variable and correlated neither with climate/microclimate nor with habitat. However, FHT ability taken as a whole appeared higher in North American populations than in European ones. Some A. bisporus var. bisporus isolates revealed a good potential for cultivation at 25 degrees C.

En el marco de la interdisciplinariedad como necesidad y estrategia epistemológica, se presenta un cuerpo de consideraciones teóricas, metodológicas, conceptuales y ontológicas, dirigidas a revisar, críticamente, proposiciones que permitan formular una perspectiva de análisis y síntesis sustentada en la Geohistoria y la Ecogeografía. Se trata de dos interdisciplinas cuyos métodos e instrumentos conceptuales permiten avanzar en el estudio "comprehensivo" de los niveles de organización e integración del espacio, de conformidad con la dinámica de variables sociales y físico-naturales intervinientes. En tal sentido, se parte de la concepción dialéctico-materialista como metodología para comprender los nexos definidores de la relación sociedad-naturaleza, sistema complejo que requiere la adopción de criterios y orientaciones particulares, ante las condiciones de heterogeneidad y cambio permanente que le son intrínsecas. Se formula dicha perspectiva considerando el valor sustantivo la acción antrópica sobre el espacio, pero enfatizando el tratamiento de procesos morfoestructurales, morfobioclimáticos y, en general, ecodinámicos (soporte natural), que diferencialmente se constituyen en condicionantes de la intervención y producción técnico-social. De este modo se establecerán, a partir de constructos conceptuales y teóricos definidos mediante investigación y reflexión sistemática, proposiciones epistemológicas para avanzar en la comprensión integral del espacio geográfico con fines cognitivos y educativos. In the context of interdisciplinarity as need and epistemological strategy, this paper presented a body of theoretical, methodological, conceptual and ontological considerations, directed to review, critically formulate propositions that allow a perspective of analysis and synthesis based on Geohistory and Ecogeography. These two interdisciplines whose methods and conceptual tools allow advance the "comprehensive" study of the levels of organization and integration of space, in accordance with the dynamics of social and ecological variables involved. In this sense, it is part of the dialectical-materialist conception as a methodology to understand the relationship of society-nature, complex system that requires the adoption of standards and specific guidelines, to the conditions of heterogeneity and permanent change that are intrinsic to it. Such a perspective is developed considering the substantive value of human action on the space, but emphasizing the treatment of morphostructural, morfobioclimatic processes and generally ecodynamic (natural support), which differentially constitute determinants of intervention and technical-social production. This will be established from conceptual and theoretical constructs defined through research and systematic reflection, epistemological propositions to advance the comprehensive understanding of the geographical space with cognitive and educational purposes. 227 - 250 geoense@ula.ve Semestral

In this essay, the author describes coastal landscapes since XVIIe century. He tries to show that human glance on the coast was different at each period. To-day, coastal zones are increasingly under development pressure and all the forms of management and conservation have been changed. A model of each stage is purposed., Le littoral inventé à la fin du XVIIIe siècle ne correspond plus à celui d'aujourd'hui. Un effort de description s'impose pour rendre compte de la complexité des lieux. Les figurations proposées permettent de transcrire graphiquement autant le projet anthropologique que le programme mésologique qui définissent tout secteur côtier. La transformation de ce territoire du vide peut être ainsi mise en évidence visuellement pour les quatre derniers siècles., Bousquet Bernard. Du littoral. Essai d'identification. In: Cahiers du Centre nantais de recherche pour l'aménagement régional, n°35-36, 1990. Gros temps sur les côtes… Le littoral au péril de la mer… et des hommes. pp. 77-98.

16 pages, 4 figures, 3 tables, 48 references. We are most indebted to Redouan Ajbilou, F. Barreto Caldas, M. Joao Gonçalves, Antonio Jordán, Joao Ormonde, Ana Ortega, Iñigo Sánchez, and the colleagues in the Núcleo de Ecologia Vegetal of the Universidade do Porto, the Universidade de Coimbra, and the Jardin Botánico de Lisboa for providing us with prelim- inary information to locate populations and helping with field sampling. M. Eugenia Díaz, M. Dolores Díez, Ernesto Gallego, Pedro Garrido, Rosario Hidalgo and Anass Terrab also helped with field sampling. Rafael López and the staff of the Soil Laboratory at the IRNA carried out the soil analyses. Rodrigo Tavera for drawing the Fig. 2. J.P. Rodríguez and one anonymous reviewer for their comments improving an earlier version of the manuscript., We analyse populations of the insectivorous plant Drosophyllum lusitanicum (L.) Link (Droseraceae) and their habitats throughout the species' distribution range (Portugal, Spain and Morocco), and examine their relations. We have surveyed 32 populations and we analyse their demographic structures, accompanying plant communities (by TWINSPAN analyses), and relationships between population features and several edaphic and nonedaphic environmental variables (by multiple regression analyses). Plant communities, their floristic richness and degree of endemism change across the geographical range of Drosophyllum. Populations vary strongly in size, density and age structure. Their recruitment seems largely determined by competition with the surrounding vegetation, while only weak relationships were detected between population performance and other environmental factors. The demographic structure of populations exhibits a marked geographical differentiation, with populations becoming older and sparser towards the north-western part of the range. The largest and presumably most stable populations are mostly found in southern Spanish heathlands, which are nowadays scarcely affected by man. Moroccan populations suffer from browsing by cattle and experience an accelerated generation turnover, while most Portuguese populations occur in afforested areas and experience strongly reduced recruitment. The historical distribution range of Drosophyllum within its peculiar habitat has probably been relatively stable, but recent regional differences in human land use have resulted in present-day differences in population performance, as well as in types and degrees of threat across the three countries involved. Conservation strategies should take into account this range-wide variation and combine approaches on different spatial scales., Fieldwork was supported by DGICYT grant PB95-551, T.M. was supported by DGES grant PB97-1177, and A.H and J.A. by DGESIC grant PB 98–1144.

Foliage, cones and seeds of Cupressus bakeri were collected from 5 1 trees in 6 populations from the NE and NW flanks of Goosenest Mountain in the Cascade Ranges of California. Biometrical analyses showed a high degree of differentiation among populations despite their geographic proximity. Population GN2, from the NW side of the mountain, was most distinct from all others. Variation between populations GN1 and GN2 was surprisingly great considering their close proximity, and similar ecological conditions, suggesting genetic differentiation. Morphological differences among populations of the NE side of the mountain (GN4, GN5 and GN6) may have been due to phenotypic plasticity to differing ecological conditions. These latter populations had characteristics similar to those of the Siskiyou Mountains, suggesting that Goosenest Mountain can be considered a region of transition and differentiation in this species., Les feuilles, les cônes et les graines de 51 individus de Cupressus bakeri Jeps. ont été récoltés dans 6 populations naturelles du versant NE et NW du Mont de Goosenest dans la chaîne montagneuse de Cascades en Californie. L’analyse multivariante effectuée sur les caractères biométriques a montré un degré élevé de différenciation entre les diverses populations, même géographiquement très proches. La population GN2 du versant NW est bien distincte des autres. La variation entre les populations GN1 et GN2, très voisines, dans des conditions écologiques similaires, est surprenante et nous suggérons qu’il s’agit d’une différenciation plutôt d’origine génétique. La différence morphologique observée entre les populations du versant NE (GN4, GN5, GN6) est due aux conditions écologiques : c’est une différenciation phénotypique. Ces dernières populations possèdent les caractéristiques de celles du Mont Siskiyou et cela nous a incités à penser que le Mont de Goosenest pourrait être en effet une zone de transition et de différenciation pour cette espèce., Dodd Richard S., Afzal-Rafii Zara, Power Ariel B. Biodiversity within natural populations of Cupressus bakeri (Goosenest Mountain, California). In: Ecologia mediterranea, tome 16,1990. pp. 51-57.

Background Humans threat the populations of tree species by overexploitation, deforestation, land use change, and climate change. We present a novel threat assessment at intraspecific level to support the conservation of genetic resources of 80 socioeconomically viable tree species in South America. In this assessment, we evaluate the threat status of Ecogeographic Range Segments (ERSs). ERSs are groups of populations of a specific species in a certain ecological zone of a particular grid cell of a species’ geographic occupancy. Methods We used species location records to determine the species distributions and species‐specific ERSs. We distinguished eight threat situations to assess the risk of extirpation of the ERSs of all 80 species. These threat situations were determined by large or little tree cover, low or high human pressure, and low or high climate change impact. Available layers of tree cover and threats were used to determine the levels of fragmentation and direct human pressure. Maxent niche modelling with two Global Circulation Models helped determining climate change impact by the 2050s. Results When all 80 species are considered, in total, 59% of the ERSs are threatened by little tree cover or high human pressure. When climate change is also considered, then 71‐73% of the ERSs are threatened. When an increased risk of extirpation of populations outside protected areas is considered, then 84–86% of the ERSs are threatened. Seven species warrant special attention because all their ERSs are threatened across their whole distribution in South America: Balfourondendron riedelianum, Cariniana legalis, Dalbergia nigra, Handroanthus pulcherrimus, Pachira quintana, Prosopis flexuosa, and Prosopis pallida. Conclusions Our results confirm the urgency to set up a regional action plan for the conservation of tree genetic resources in South America. With this threat assessment, we aim to support governments and organizations who are taking up this task.