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Chiroptera is the only mammalian order that has adapted to active flight, offering a unique platform to study ecomorphological adaptations. While bats exhibit a diverse diet, the focus of this study is on insectivorous bats, specifically four species: Myotis daubentonii, Nyctalus noctula, Plecotus austriacus and Rhinolophus ferrumequinum. It is important to note that despite sharing an insectivorous diet, these species occupy different ecological niches, perform distinct feeding strategies and explore varied habitats to capture prey. Using 2‐D geometric morphometrics, we analysed a sample of mandibles to identify differences in size and shape among these species. We also investigated ecogeographical variation within their overlapping distribution across continental Europe. Significant differences in both mandibular size and shape were found among the four species. Sexual dimorphism influenced only the mandibular shape of R. ferrumequinum. A latitudinal gradient in mandibular size was found solely in N. noctula, while longitude significantly explained shape variation in M. daubentonii. These findings suggest that even within the ecological guild of insectivorous bats, there exists a diverse range of morphological adaptations that allow these species to occupy distinct ecological niches. [ABSTRACT FROM AUTHOR]

Arid and semi-arid areas are highly productive ecosystems that have a great diversity of species, among which grasses stand out. These species have ecological, environmental, and economic importance. The objective was to identify the ecological descriptors of 15 native species of grasses and diversity patterns through multivariate analysis techniques (principal component analysis, PCA, and cluster analysis, CA), in addition to identifying potential distribution areas (current and future) and regions of high and low diversity from 3841 accessions and 21 climatic variables. Among the main results, the extreme values, coefficient of variation, and median for each species could be determined. PCA determined that, with 10 variables, it was possible to explain 54.36% of the variation between the analyzed species. CA resulted in the formation of four statistically significant groups, with specific climatic characteristics. Regarding potential distribution areas and climate change, a reduction in distribution is expected (2050) on most of the current surface, with a possible opportunity zone in the north of the country. Finally, two hotspots (high diversity areas) and four coldspots (low diversity areas) were identified among the analyzed species. These results can be used to create strategies for sustainable use and the conservation of these resources.

Abstract. The expansive range of Lewis flax (Linum lewisii), an herbaceous perennial, exposes the species to a diversity of climatic conditions. As interest in the domestication and adoption of perennial crop alternatives grows and interest in this species for natural area restoration continues, the assurance of a commercial plant variety's ability to endure the full range of possible climatic extremes is paramount. This study examines the freezing tolerance of a geographically representative sampling of 44 Lewis flax accessions at winter temperature extremes experienced in the northern Great Plains of the USA. Survival analysis models were adapted to include temperature exposure, in replacement of ordinal time typically used in such models, to produce statistics evaluating reactions to extreme temperatures that Lewis flax would encounter in our field environments. Our results revealed Lewis flax is more freezing tolerant than previously reported, and revealed four accessions with significantly superior genetic freezing tolerance than the released 'Maple Grove' cultivar. Furthermore, regrowth analyses indicate variation among accessions not associated with survival, which could lead to improving regrowth rate and survival simultaneously. These findings and their methodology expand the understanding of Lewis flax adaptation for winter hardiness and offer an efficient, new model that can be used to evaluate freezing tolerance at ordinal temperatures without requiring extensive prior physiological knowledge for a species. [ABSTRACT FROM AUTHOR]

Arid and semi-arid areas are highly productive ecosystems that have a great diversity of species, among which grasses stand out. These species have ecological, environmental, and economic importance. The objective was to identify the ecological descriptors of 15 native species of grasses and diversity patterns through multivariate analysis techniques (principal component analysis, PCA, and cluster analysis, CA), in addition to identifying potential distribution areas (current and future) and regions of high and low diversity from 3841 accessions and 21 climatic variables. Among the main results, the extreme values, coefficient of variation, and median for each species could be determined. PCA determined that, with 10 variables, it was possible to explain 54.36% of the variation between the analyzed species. CA resulted in the formation of four statistically significant groups, with specific climatic characteristics. Regarding potential distribution areas and climate change, a reduction in distribution is expected (2050) on most of the current surface, with a possible opportunity zone in the north of the country. Finally, two hotspots (high diversity areas) and four coldspots (low diversity areas) were identified among the analyzed species. These results can be used to create strategies for sustainable use and the conservation of these resources. [ABSTRACT FROM AUTHOR]

Tropical mangroves are known to support fish production, but natural variability in the link between mangrove habitats and fish populations undermines our ability to manage, conserve and restore this ecological relationship. This is largely due to undefined context‐dependence in the use of mangroves by fish. We collected a spatially extensive dataset of 494 mangrove fish assemblages using standardised Remote Underwater Video surveys of mangrove edge habitats from five environmentally heterogenous regions in the Indo‐Pacific. We used machine learning methods to define contextual limits of the use of mangroves by reportedly mangrove‐affiliated fish. We found that tidal range and proximity to coral reefs were the most important contextual predictors of the use of mangroves by most taxa. We established data‐driven threshold values for important contextual predictors of the use of mangroves by fish, offering new insights into the variable role played by tropical mangroves in supporting fish life histories. Where mangroves occur as part of reef seascapes in regions with limited tidal range (<1.5 m), they appear to serve an important juvenile habitat function for a wide spectrum of reef fish. In regions with substantially larger tidal ranges, mangroves appear to only support certain reef species with coastal life histories. Coastal and estuary fish were able to use mangroves in a wide variety of non‐reef contexts. We demonstrate that key thresholds in environmental context can govern the functional role of mangroves, with strong implications for the role of other habitats in coastal seascapes. [ABSTRACT FROM AUTHOR]

Aquatic ectotherms often attain smaller body sizes at higher temperatures. By analysing ~15,000 coastal‐reef fish surveys across a 15°C spatial sea surface temperature (SST) gradient, we found that the mean length of fish in communities decreased by ~5% for each 1°C temperature increase across space, or 50% decrease in mean length from 14 to 29°C mean annual SST. Community mean body size change was driven by differential temperature responses within trophic groups and temperature‐driven change in their relative abundance. Herbivores, invertivores and planktivores became smaller on average in warmer temperatures, but no trend was found in piscivores. Nearly 25% of the temperature‐related community mean size trend was attributable to trophic composition at the warmest sites, but at colder temperatures, this was <1% due to trophic groups being similarly sized. Our findings suggest that small changes in temperature are associated with large changes in fish community composition and body sizes, with important ecological implications. [ABSTRACT FROM AUTHOR]

Context: There are not many analyses of variation in patterns and potential causes of tree death in eucalypt forests covering wide environmental gradients. Aims: To determine the environmental patterns of standing and fallen dead trees in forests over 1200 m of elevation and whether tree death has increased as the climate has become warmer, drier and windier. Methods: We measured tree death in 2011 and 2021 in the lowland to subalpine forests near Hobart, Tasmania, Australia and determined the best predictors of its incidence and change. High-resolution satellite images obtained from Nearmap were perused to count dead standing trees, fallen dead trees and live trees in a stratified random selection of 250, 4 ha sites, 10 of which were ground-truthed. Elevation, climatic variables, aspect, slope, fire history, soil type and vegetation type were used as potential predictors of tree death. General linear models were developed to explain response variables. Key results: Standing dead trees increased 133% from 1.7 to 2.3 per ha between 2011 and 2021. Fallen dead trees increased 160%. Variables that were significant in at least one of the models for 2011 standing dead trees, 2011 fallen trees, change in standing dead trees 2011–2021 and changes in fallen dead trees 2011–2021 were elevation, fire history, aspect class, several vegetation types and several soil types. Conclusions: Deficits in soil moisture as a major cause of death is consistent with several components of these models, with fire history possibly having a legacy effect and wind exposure possibly influencing the balance between standing and fallen dead trees. Implications: Tree mortality is likely to move upslope with warming and drying. Managing the understorey of dry forests using fire might help in reducing competition for moisture, and, thus, reduce tree death in susceptible forest communities, but severe fires are likely to cause considerable mortality. Changes in standing and fallen dead trees between 2011 and 2021 were measured over a study area near Hobart, Tasmania which ranged from lowland dry forest to subalpine forest. Both standing and fallen dead trees increased in this period of increasing drought and wind stress. Elevation, February temperature, fire history, aspect class, several vegetation types and several soil types influenced at least one of our mortality variables. It may be possible to mitigate drought effects by understorey burning. [ABSTRACT FROM AUTHOR]

Ecogeographic research into how species' forms vary across space, time, and climate has taken on new urgency due to contemporary global climate change. Research using museum specimens and other records to study biological rules like Bergmann's, Allen's, and Gloger's Rules has a long history and continues to generate publications and robust scientific debates. Despite the prevalence and history of the field, however, no simple guide on how to carry out such work has ever been published. To lower the barriers of entry for new researchers, this review was created as a practical guide on how to perform ecogeographic research. The guide consolidates disparately published methodologies into a single, convenient document that reviews the history and present of the field of ecogeographic rule research, and describes how to generate appropriate hypotheses, design experiments, gather, and analyze biotic and geographic data, and interpret the results in an ecologically meaningful manner. The result is a semi‐standardized guide that enables scientists at all levels from any institution to carry out an investigation from start to finish on any biological rule, taxon, and location of their choice. [ABSTRACT FROM AUTHOR]

Many insects have been studied over wide geographical areas to determine whether they follow Bergmann's Rule, which predicts that animal clades or populations should have smaller body sizes in warmer climates. While this ecogeographic rule is well supported in mammals and birds, insect latitudinal sizes can show Bergmann, converse Bergmann, or no size clines at all. Museum collections are typical sources of data for insect clines, and long-term collections should reflect rising global temperatures and shifting climates, possibly producing temporal size clines along with any geographical clines. We hypothesize that insects with Bergmann clines geographically will show Bergmann-like clines temporally as well, and that the converse and inverse of this rule are also true. By looking at museum samples going back a century, we tested whether Anomala expansa expansa (Bates, 1866), a species of Scarabaeidae beetle common in lowland Taiwan, was experiencing long-term changes in body size in response to rising temperatures. We found that overall, the size of these beetles increased over time. Within Taipei populations, this increase was correlated with rising average yearly temperatures. The impact of this pest species' rising size with time will need to be monitored, and temporal size clines in other pests need to be investigated. [ABSTRACT FROM AUTHOR]

In contemporary times, the imposition of the economic paradigm on environmental practices adopted by the development models undertaken is perceived. Consequently, the results are environmental and social impacts that de-characterize the landscape, unbalance the ecogeographic systems and services, and harm the quality of the environment and the quality of life of the populations. Thus, environmental planning and management works substantiated by Environmental Education practices are fundamental for the conservation and preservation of the natural environment, as well as for the construction and consolidation of a new geoecological consciousness. This study discusses the epistemological bases and the methodological framework of Geoecology of Landscapes and Applied Environmental Education aiming at territorial planning and management with a view to equitable land use planning. It has sustainable development as a horizon and Applied Environmental Education as a strategy, both for planning and environmental management as for construction, consolidation, and implementation of geoecological awareness to change perception, values, and environmental attitudes.

In contemporary times, the imposition of the economic paradigm on environmental practices adopted by the development models undertaken, is perceived. Consequently, the results are environmental and social impacts that de-characterize the landscape, unbalance the ecogeographic systems and services, and harm the quality of the environment and the quality of life of the populations. Thus, environmental planning and management works substantiated by Environmental Education practices are fundamental for the conservation and preservation of the natural environment, as well as for the construction and consolidation of a new geoecological consciousness. This study discusses the epistemological bases and the methodological framework of Geoecology of Landscapes and Applied Environmental Education aiming at territorial planning and management with a view to equitable land use planning. It has sustainable development as a horizon and Applied Environmental Education as a strategy, both for planning and environmental management as for construction, consolidation and implementation of geoecological awareness to change perception, values and environmental attitudes. [ABSTRACT FROM AUTHOR]

One of the major challenges of ecologists and biogeographers is to understand how species are globally distributed. Two of the most well-studied large-scale patterns in species distributions are the Rapoport's rule and the Latitudinal Diversity Gradient (LDG). We aimed to address whether Neotropical odonates follow the Rapoport's rule and if there is a latitudinal gradient in species diversity. A total of 1076 records for 190 species, covering a large area from southeastern to the northern regions of Brazil that extends from 23°S (Cerrado) to 3°N (Amazon Rainforest). Generalized Linear Models were used to address whether Neotropical odonates follow the Rapoport's rule, and if there is a latitudinal gradient in species diversity, based on our predictions. We found a Rapoport effect in the Amazon biome and an inverse Rapoport effect in the Amazon-Cerrado Transition Forest and Cerrado biome. Regarding LDG, we found no significant effect of latitude on species richness patterns when we considered all the species, and a significant relationship between species richness and latitude for zygopterans. The spatial patterns of odonates geographic distribution may be an outcome of geographical barriers, for instance, the continental geometry of South America, which is broader in the north and limits geographical expansion towards the south. Furthermore, species ecophysiological mechanisms may also hamper their expansion and drive the pattern observed in our study, mainly because of evolutionary thermoregulatory adaptations that each taxon exhibits along its environmental gradient. [ABSTRACT FROM AUTHOR]

The chief subject of this brief overview is a vetch species, once distinguished as Vicia calcarata Desf. and currently regarded as V. monantha Retz. subsp. triflora (Ten.) B. L. Burtt & P. Lewis, but we prefer to distinguish this taxon at species level as Vicia calcarata. It is a volunteer plant occurring regularly on ruderal sites in the local floras of the coastal and maritime areas of the Mediterranean Basin, and sporadically happens to be cultivated in fields. It has a more robust growth habit than V. monantha subsp. monantha, with usually three flowers per peduncle and larger seeds, rather constant morphological traits. In situ and on-farm observations on V. calcarata are scarce, relating mostly to the southern mainland of Italy and its islands, Spain, North Africa and Syria, where it is found in forests, grasslands, wheat fields, ruderal soils and along roadsides. On a global scale, there are 91 accessions of V. calcarata in six ex situ genebank collections in Alcalá de Henares, Bari, Beirut, Gatersleben, Sadovo and St. Petersburg. In a series of ex situ field trials in Novi Sad, twelve accessions of V. calcarata produced average yields of 6.3 t ha−1 of forage dry matter and 1100 kg ha−1 of seed. There are promising perspectives for developing cultivars of V. calcarata, since the available divergence offers a solid basis for crop improvement. After a long fall, a novel rise of V. calcarata is yet to come. [ABSTRACT FROM AUTHOR]

Ecogeographical rules predict an association between specific adaptive morphological/physiological traits and latitude, elevation or cooler climates. Such ecogeographical effects are often expressed most clearly in widely distributed species due to continuous selective adaptation occurring over their geographic range. Based on 40 population sampling sites of 116 adult individuals (female, n = 44 ; male, n = 72) across an elevational range of 191–2573 m, we tested whether morphological traits accorded with predictions of Bergmann's rule, Allen's rule and Hesse's rule for the South China field mouse (Apodemus draco). The effects of elevation on body size, appendage length and heart size were tested by fitting Linear Mixed-Effects Models. None conformed to Bergmann's, Allen's or Hesse's rule. Clines in body size opposed Bergmann's rule, and foot and snout length ratios opposed Allen's rule. We conclude that South China field mice, a widely distributed species, exhibit an acute thermoregulation mechanism in which in colder conditions body sizes decrease – as opposed to altering heart sizes or surface area to volume ratios – requiring less energy to regulate body temperatures. Also, there was a stronger selective pressure to increase partial appendage lengths (i.e., foot and snout) to adapt to the specific environment (e.g. longer period of snow cover, up to 2573 m) rather than on a general shortening of appendages to cope with colder conditions. [ABSTRACT FROM AUTHOR]

Bats are among the important indicator species which indicate how the quality of an ecosystem and habitat changes against threats. Turkey has a rich geography containing a wide variety of ecosystems and habitats for bats. The distributions of the bats in Turkey based on ecogeographic regions was discussed in this study. 152 records belonging to 28 bat species obtained as a result of the field works carried out between 2004 and 2018 as well as the records of the bats obtained from 131 previous studies conducted in Turkey were examined together and their current distributions were determined based on 10 ecogeographic regions. As a result of this study, it was stated that 39 bat species have existed in Turkey so far. Among these species, IUCN criteria and their current distributions in Turkey were compared with a simple scoring. As a result, it was suggested that 5 species considered to be under least concern (LC) according to IUCN criteria were rare or under threat in Turkey. In this study, important distribution data were presented to be used in the determination of the effects of the human activities (wind power stations, habitat damage, opening caves to tourism etc.), which affect bat population negatively, on bats. The conservation status and distributions of bats based on ecogeographic regions were presented for the first time in Turkey. In consideration of this information, it was determined that the bats in Turkey were under threat in terms of their ecosystems and it is required to determine the conservation status at the national level compatible with IUCN criteria. [ABSTRACT FROM AUTHOR]

Abstract 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.

Objectives: Humans generally comply with the ecological rule of Allen (1877), with populations from tropical environments exhibiting body proportions in which limb segments are long relative to trunk height compared to temperate groups. This study tests whether ecogeographic differences in intralimb proportions are identifiable among two modern fetal samples of differing ancestry. Materials and methods: Data are derived from radiographic measurements of long bone diaphyseal length and crown‐heel length (CHL) of contemporary, spontaneously aborted fetuses of African Americans ("black") of assumed African (tropical) ancestry and European Americans ("white") of assumed European (temperate) ancestry (n = 184). Population individual limb elements, brachial, and crural indices are compared via analyses of covariance (ANCOVA). Potential patterns of divergent allometric growth are quantified through principal components analysis (PCA). Results: African ancestral distal limb elements were consistently, albeit slightly, longer than those of European ancestry, relative to CHL. None of the ANCOVA interactions with ancestry are statistically significant for limb indices. The radius was the only single element that displayed a statistically significant ancestry effect (p = 0.0435) equating to a 1 mm difference. PCA highlights that upper limbs demonstrate negative allometry and lower limbs demonstrate positive allometry with sample‐specific multivariate growth patterns being nearly identical. Differences in growth allometry late in gestation make little contribution to observed differences in adult limb proportions. Discussion: No statistically significant ecogeographic patterns were appreciated among intralimb proportions between these groups during the fetal period. This study contributes to a greater appreciation of phenotypic plasticity, ecogeographic variation in ontogeny, and the evolution of modern human diversity. [ABSTRACT FROM AUTHOR]

The terrestrially hibernating wood frog (Rana sylvatica) is well-known for its iconic freeze tolerance, an overwintering adaptation that has received considerable investigation over the past 35 years. Virtually, all of this research has concerned frogs indigenous to the temperate regions of its broad range within North America. However, recent investigations have shown that frogs of subarctic populations are extremely cold hardy, being capable of surviving freezing for longer periods and at much lower temperatures as compared to conspecifics from temperate regions. Their exceptional freeze tolerance is partly supported by an enhanced cryoprotectant system that uses very high levels of urea and glucose to limit ice formation, regulate metabolism, and protect macromolecules and cellular structures from freezing/thawing stresses. In the weeks before they begin hibernating, northern frogs undertake radical physiological transitions, such as depletion of fat stores and catabolism of muscle protein, that prime the cryoprotectant system by accruing urea and stockpiling glycogen from which glucose is mobilized during freezing. Concentrations of cryoprotectants ultimately achieved in Alaskan frogs when freezing occurs vary among tissues but generally are higher than those of frogs inhabiting milder climates. This review summarizes the molecular, biochemical, and physiological adaptations permitting this northern phenotype to survive the long and harsh winters of the region. [ABSTRACT FROM AUTHOR]

Lathyrus cicera L. is one of the oldest cultivated plants in the world, originating in the Mediterranean centre of diversity. Together with its close relative, L. sativus, it is most likely the first crop domesticated in Europe, namely in the Iberian Peninsula and southern France. Today, L. cicera is sharing the destiny of numerous, legume, cereal and other once widely grown species, becoming largely neglected and underutilised, extremely sporadically cultivated for food and feed, with almost no breeding strategies and often escaping from local agricultures into neighbouring wild flora. Still, numerous in situ and on-farm investigations confirm that L. cicera has a remarkable infraspecific diversity, which, along with the existing ex situ collections across the world, proves as a solid basis for its improvement and reintroduction. There are sufficient resources for both developing new advanced cultivars and maintaining the locally cultivated and maintained landraces. Lathyrus cicera has a considerable potential for producing more than 8 t ha−1 of forage dry matter (hay) and around 3.6 t ha−1 of dry grain, with a dry matter crude protein content in both surpassing 250 g kg−1, for a substantial reduction of the content of neurotoxin oxalyldiaminopropionic acid (ODAP), an enhanced resistance to various stress factors, such as drought, low temperatures, powdery mildew, pseudomonas, rust or crenate broomrape, for a safe inclusion into human diets and animal feeding and for various environment-friendly uses. Equally important for reintroducing L. cicera is the promotion of the currently rather rare regional folk customs and gastronomic festivals devoted to this cultivated plant, such as the Sagra della maracucciata, regularly celebrating maracuoccio, as it is called in the Chilentan dialect, in the Camerotan hamlet of Lentiscosa, in southwest Italy, with thousands of visitors from elsewhere and for more than a decade. [ABSTRACT FROM AUTHOR]

We examined a dataset of body sizes comprising 3209 species of Mesostigmata to test two hypotheses regarding body size patterns: that species living in symbiotic relationships differ in size compared with those that are free-living, and that mite species show geographic body size gradients. We found that Mesostigmata in symbiotic relationships are considerably larger than those that are free-living, but the type of symbiosis (commensal versus parasitic) had little influence on body size. We also found that free-living mite species fit a Bergmann size cline (larger species in cool climates), but mite species in commensal relationships show a converse Bergmann size cline (larger species in warm climates) while no pattern was found for parasitic species. These results fit a resource-based explanation for both patterns. We hypothesize that animals that use more easily obtainable resources grow larger, through resource pulses in temperate zones for free-living mites and use of concentrated resources for commensal and parasitic species. Available microhabitats could also promote smaller sizes in free-living Mesostigmata: i.e. soil and plants offer more and smaller microhabitats to exploit and are hence occupied by smaller species. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Seed weight is a key fitness-related trait associated with plant adaptation and is commonly targeted in plant breeding. Aims: We evaluated seed weight variation within and between Trichloris crinita and Trichloris pluriflora across their geographical ranges in Argentina. Methods: Genetic variation in seed weight was evaluated through a common garden experiment. To examine the possible role of such variation in local adaptation, we compared the seed weight of plants of populations raised in the common garden with seed weight variation and ecogeographical variables across their original habitats. We also evaluated experimentally 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 several ecogeographical variables. Larger seeds of T. crinita were associated with more stressful environments and produced larger 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 an advantage during early developmental stages, particularly under stressful conditions. Such knowledge should prove helpful in selecting the most suitable populations for restoration and plant breeding. [ABSTRACT FROM AUTHOR]

Objectives Declination in femoral neck-shaft angle (NSA) is commonly linked to an increased level of physical activity during life. More recently, however, research suggests that lower NSA might also be explained, in part, as the mechanical consequence of differences in ecogeographic body proportions. This study tests the proposed link between NSA and climatic-induced body proportions, using relative body mass (RBM), throughout the course of development. Materials and Methods NSA and RBM were collected for 445 immature remains from five geographic locations. NSA and RBM were standardized for age-effects. ANOVA was used to examine when population differences emerged in both NSA and RBM. Regression analyses were used to examine the pattern of relationship between NSA and RBM. Results Populations differ significantly in NSA and RBM before skeletal maturity, and these differences occur early in life. While both NSA and RBM change over the course of development, no significant relationship was found between NSA and RBM for any sample, or any age category ( p = .244). Discussion Individuals who have relatively greater relative body mass do not necessarily have lower NSA. Population differences in NSA were found to be variable, while differences in RBM remained consistent across the developmental span. Taken together, these results suggest that regardless of body proportions, the degree of declination of NSA is presumed to be similar among individuals with similar gait and ambulatory behaviors. Conversely, populations differ in RBM from birth, and these differences are consistent throughout development. These two measures likely are responsive to diffing stimuli, and any potential relationship is likely complex and multifactorial. [ABSTRACT FROM AUTHOR]

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’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.

Coastal marine Gasterosteus aculeatus were captured from seven locations along the Pacific coast of North America, ranging across 21·8° latitude to test Jordan's rule, i.e. that vertebral number should increase with increasing latitude for related populations of fish. Vertebral number significantly increased with increasing latitude for both total and caudal vertebral number. Increasing length with latitude ( sensu Bergmann's rule) was also supported, but the predictions for Jordan's rule held when controlling for standard length. Pleomerism was weakly evidenced. Gasterosteus aculeatus exhibited sexual dimorphism for Jordan's rule, with both sexes having more vertebrae at higher latitudes, but only males showing a positive association between latitude and the ratio of caudal to abdominal vertebrae. The number of dorsal- and anal-fin rays and basals increased with increasing latitude, while pectoral-fin ray number decreased. This study reinforces the association between phenotypic variation and environmental variation in marine populations of G. aculeatus. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Vicia sativa s.l. is one of the most commonly grown forage crop in Mediterranean regions. It is widely distributed and presents at the same time the largest overlaps and the most difficult taxonomic problems. The present study is an attempt to characterize the diversity and the taxonomic relationships among the members of a collection of 34 V. sativa s.l. from a variety of geographical sources of North Algeria with the aim to improve their conservation and management along with a synthesis of the results obtained by previous researchers. Four taxa ( obovata, cordata, consobrina and angustifolia) were analysed using 5 ecogeographic parameters and 78 morphological characters coded as multistate. The results reflect the great diversity of vetches and subspecies were not clearly recognizable from their plant morphology and ecogeography. Cluster analysis does not have provided clear separation among accessions. 11 morphological characters were excluded as they are homologous between all accessions. Important variation in standard colour, leaflets pairs per leaf, tendril length, hilum length and legume suture curvature was found in most accessions of the collection. Even for the characters that contribute the most to the separation of the accessions, the range of variation does show overlap between the subspecies. The study has drawn accessions from a wider geographical range and a distribution map of each taxa was produced. The information obtained can be used as a guide for future collecting missions. Variation in morphological characters appeared to be related to the site from which the accession was collected with 44.89 %. [ABSTRACT FROM AUTHOR]

Beautiful Vavilovia [ Vavilovia formosa (Stev.) Fed.] is a perennial legume of great importance for the evolution and taxonomy of the tribe Fabeae Rchb. The abundant data on its collection sites on the Caucasus Mountains, made during the past two centuries, were collated and analysed. The studied area covers the mountain ranges of both the Greater and Lesser Caucasus in Russian Federation, Georgia, Armenia and Azerbaijan, except the ranges in north-eastern and eastern Turkey and north-western Iran. The presented data are the results of an analysis of the herbarium collections of various institutions and available literature resources, providing novel information about 110 collection points. The analysed data allowed to specify the borders of the area in the region, as well as describe the features of the high-altitude distribution of V. formosa within the studied area, revealing the lower and upper altitude ranges as between 2021 and 3500 m above sea level. The results also indicate a reduction of the number of its populations, as well as the necessity and urgency of monitoring and protecting all the known locations of this highly endangered species. [ABSTRACT FROM AUTHOR]

Homo erectus was the first hominin to exhibit extensive range expansion. This extraordinary departure from Africa, especially into more temperate climates of Eurasia, has been variously related to technological, energetic and foraging shifts. The temporal and regional anatomical variation in H. erectus suggests that a high level of developmental plasticity, a key factor in the ability of H. sapiens to occupy a variety of habitats, may also have been present in H. erectus. Developmental plasticity, the ability to modify development in response to environmental conditions, results in differences in size, shape and dimorphism across populations that relate in part to levels of resource sufficiency and extrinsic mortality. These differences predict not only regional variations but also overall smaller adult sizes and lower levels of dimorphism in instances of resource scarcity and high predator load. We consider the metric variation in 35 human and non-human primate 'populations' from known environmental contexts and 14 time- and space-restricted paleodemes of H. erectus and other fossil Homo. Human and non-human primates exhibit more similar patterns of variation than expected, with plasticity evident, but in differing patterns by sex across populations. The fossil samples show less evidence of variation than expected, although H. erectus varies more than Neandertals. This article is part of the themed issue 'Major transitions in human evolution'. [ABSTRACT FROM AUTHOR]

For the first time, a faunistic list of the Chironomidae fauna of Greece is presented along with its ecological distribution. Chironomidae larvae and pupal exuviae were collected from 61 locations in mainland Greece during 2006–2008. 76 taxa (genera to species) were recorded. The genera Potthastia, Brillia, Euorthocladius, Synorthocladius, Tvetenia and Xenochironomus are recorded for the first time from Greece. Furthermore, 12 species are new for Greece and five are new for mainland Greece. Chironomidae collected from running waters were analysed with ordination techniques. The results revealed that Chironomidae assemblages were distinguished into three ecoregions with distinct climatic, geological and hydrochemical features. Running waters in Northwestern Greece were generally dominated by species tolerant to water acidification. Chironomids typical of eastern uplands preferred relatively slow current and soft bottom sediments. Assemblages of the southern Peloponnese Peninsula were represented by species of relatively fast flowing, warm streams. However, these are only preliminary results and many more data are needed to justify this ecological distinction of Chironomidae assemblages. This is the first study contributing to the knowledge of a rather neglected insect group of the Greek fauna. It is expected that more species remain to be identified and recorded and future works will contribute to this initial faunal list. [ABSTRACT FROM PUBLISHER]

We investigated hibernation physiology and freeze tolerance in a population of the wood frog, Rana sylvatica, indigenous to Interior Alaska, USA, near the northernmost limit of the species' range. Winter acclimatization responses included a 233% increase in the hepatic glycogen depot that was subsidized by fat body and skeletal muscle catabolism, and a rise in plasma osmolality that reflected accrual of urea (to 106±10 µmol ml-1) and an unidentified solute (to ~73 µmol ml-1). In contrast, frogs from a cool-temperate population (southern Ohio, USA) amassed much less glycogen, had a lower uremia (28±5 µmol ml-1) and apparently lacked the unidentified solute. Alaskan frogs survived freezing at temperatures as low as -16°C, some 10-13°C below those tolerated by southern conspecifics, and endured a 2-month bout of freezing at -4°C. The profound freeze tolerance is presumably due to their high levels of organic osmolytes and bound water, which limits ice formation. Adaptive responses to freezing (-2.5°C for 48 h) and subsequent thawing (4°C) included synthesis of the cryoprotectants urea and glucose, and dehydration of certain tissues. Alaskan frogs differed from Ohioan frogs in retaining a substantial reserve capacity for glucose synthesis, accumulating high levels of cryoprotectants in brain tissue, and remaining hyperglycemic long after thawing. The northern phenotype also incurred less stress during freezing/thawing, as indicated by limited cryohemolysis and lactate accumulation. Post-glacial colonization of high latitudes by R. sylvatica required a substantial increase in freeze tolerance that was at least partly achieved by enhancing their cryoprotectant system. [ABSTRACT FROM AUTHOR]

Vavilovia formosa is a relict, endangered species from the highlands of the Caucasus and the Near East. Described in 1812, it has had an uncertain status and was finally recognized as a separate genus of tribe Fabeae ( Fabaceae). Our informal international group was established in 2007 to revive the interest in this species as it had been seriously neglected for decades. Here, we provide an overview of the accumulated knowledge on V. formosa and present the results of the most recent multidisciplinary research. Three expeditions were made to two locations in Armenia in 2009, providing the material for anatomical, morphological, chemical and molecular analysis. Unlike previous attempts, ex situ conservation in Yerevan and in vitro propagation, important for potential interspecific hybridization, were successful. Molecular tools were used to clarify the taxonomic position of V. formosa, often considered the closest to the extinct ancestor of the whole tribe. The analysis of four informative regions of plastid and nuclear DNA showed that V. formosa belongs to the same clade as Lathyrus and Pisum, with a distinct status. Preservation and maintenance of V. formosa remains the only basis for further development of all other scientific aspects, especially breeding and uses in agronomy. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172, 524-531. [ABSTRACT FROM AUTHOR]

Pea ( Pisum sativum L.) is grown widely throughout China and has undergone natural selection throughout its agricultural range over 2,000 years. Here we characterize collection site habitats to develop an understanding of the key selection pressures likely to be imposed by each environment to facilitate the investigation of specific adaptation. We characterized 240 collection sites of 529 pea landraces, across 25 provinces and 3 municipalities of China comprising the main pea cropping regions for climatic variables. Multivariate analyses showed that collection sites tended to cluster along geographic and abiotic stress clines. Spring sown sites and winter sown sites were clearly separated into 6 and 7 habitat type clusters respectively. In addition, regions which experience extreme abiotic stresses of frost, drought and high temperature in the reproductive period for pea landraces, were identified as targets for germplasm to be tested for respective tolerances to these stresses. [ABSTRACT FROM AUTHOR]

Polyploidy, the possession of more than 2 complete genomes, is a major force in plant evolution known to affect the genetic and genomic constitution and the phenotype of an organism, which will have consequences for its ecology and geography as well as for lineage diversification and speciation. In this review, we discuss phylogenetic patterns in the incidence of polyploidy including possible underlying causes, the role of polyploidy for diversification, the effects of polyploidy on geographical and ecological patterns, and putative underlying mechanisms as well as chromosome evolution and evolution of repetitive DNA following polyploidization. Spurred by technological advances, a lot has been learned about these aspects both in model and increasingly also in nonmodel species. Despite this enormous progress, long-standing questions about polyploidy still cannot be unambiguously answered, due to frequently idiosyncratic outcomes and insufficient integration of different organizational levels (from genes to ecology), but likely this will change in the near future. See also the sister article focusing on animals by Choleva and Janko in this themed issue. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Aim The incompleteness of information on biodiversity distribution is a major issue for ecology and conservation. Researchers have made many attempts to quantify the amount of biodiversity that still remains unknown. We evaluated whether models that integrate ecogeographical variables with measures of the effectiveness of sampling can be used to estimate biodiversity patterns (species richness) of reptiles in remote areas that have received limited surveys. Location The Western Palaearctic (Europe, Northern Africa, the Middle East and Central Asia). Methods We gathered data on the distribution of turtles, amphisbaenians and lizards. We used regression models integrating spatial autocorrelation (spatial eigenvector mapping and Bayesian autoregressive models) to analyse species richness, and identified relationships between species richness, ecogeographical features and large-scale measures of accessibility. Results The two regression techniques were in agreement. Known species richness was dependent on ecogeographical factors, peaking in areas with high temperature and annual actual evapotraspiration, and intermediate cover of natural vegetation. However, richness declined sharply in the least accessible areas. Our models revealed regions where reptile richness is likely to be higher than currently known, particularly in the biodiversity hotspots in the south of the Arabian Peninsula, the Irano-Anatolian region, and the Central Asian mountains. An independent validation data set, with distribution data collected recently throughout the study region, confirmed that combining accessibility measures with ecogeographical variables allows a good estimate of reptile richness, even in remote areas that have received limited monitoring so far. Some remote regions that support very rich communities are covered very little by protected areas. Main conclusions Integrating accessibility measures into species distribution models allows biologists to identify areas where current knowledge underestimates the actual richness of reptiles. Our study identifies regions requiring future biodiversity research, proposes a novel approach to biodiversity prediction in poorly studied areas, and identifies potential regions for conservation. [ABSTRACT FROM AUTHOR]

The debate surrounding Bergmann's rule, in which the body size of animals is predicted to be larger in cooler environments, is still open concerning ectotherms. Our goal was to test this rule in the broadest ranging amphibian species Salamandrella keyserlingii. We determined age and body size in a cooler region (Darhadyn, Mongolia: mean yearly air temperature = -8.31 °C) using skeletochronology, and compared their differences in altitude, latitude, and temperature with those of a warmer area (Kushiro, Japan: 7.98 °C). In Darhadyn, both sexes reached sexual maturity at 5-6 years of age (growth coefficient: male = 0.585, female = 0.266), 2-3 years later than those in Kushiro (male = 1.341, female = 1.129). Mean body size was smaller in Darhadyn (53.08 mm) than in Kushiro (57.63 mm) for males despite their constant metamorphic size around 30 mm. We also analyzed data available from published studies for 27 populations within the geographic range of this species from 43 to 69°N across a 2,900-km long latitudinal gradient. The analysis indicated an intraspecific tendency to decrease body size with increased latitude from 43 to 57°N, to increase size from 57 to 69°N, and to decrease body size with decreased temperature from 8 to -7 °C and increase size from -7 to -15 °C. This pattern does not follow the intraspecific extension of Bergmann's rule and may follow the converse of Terentjev's optimum rule-a rule formulated to be an inverted-U shaped curve between increased latitude (or decreased temperature) and increased body size. [ABSTRACT FROM AUTHOR]

Summary: •Arabidopsis halleri is a pseudometallophyte involved in numerous molecular studies of the adaptation to anthropogenic metal stress. In order to test the representativeness of genetic accessions commonly used in these studies, we investigated the A. halleri population genetic structure in Europe.•Microsatellite and nucleotide polymorphisms from the nuclear and chloroplast genomes, respectively, were used to genotype 65 populations scattered over Europe.•The large‐scale population structure was characterized by a significant phylogeographic signal between two major genetic units. The localization of the phylogeographic break was assumed to result from vicariance between large populations isolated in southern and central Europe, on either side of ice sheets covering the Alps during the Quaternary ice ages. Genetic isolation was shown to be maintained in western Europe by the high summits of the Alps, whereas admixture was detected in the Carpathians.•Considering the phylogeographic literature, our results suggest a distinct phylogeographic pattern for European species occurring in both mountain and lowland habitats. Considering the evolution of metal adaptation in A. halleri, it appears that recent adaptations to anthropogenic metal stress that have occurred within either phylogeographic unit should be regarded as independent events that potentially have involved the evolution of a variety of genetic mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: Low reproductive chilling tolerance in chickpea impairs ovule fertilization, delaying pod set, exposing the crop to terminal drought throughout much of its distribution range. Despite this realization, little progress has been made because of the limited genetic variation available to breeders. To address this issue a wide range of domesticated (n =1762) and wild Cicer (n =200) germplasm collected from sites stratified by flowering phase temperature was extensively field evaluated, and compared with Lupinus angustifolius, a well-adapted Mediterranean winter annual. Chilling tolerance was estimated by regressing the time interval between pod set and first flower against mean post-anthesis temperature. Field screening was augmented by smaller scale experiments evaluating the effects of contrasting post-anthesis temperature regimes on plant growth and productivity, pollen function and subsequent pod set in temperature-controlled cabinets. Chickpea was less chilling tolerant than its wild relatives, the flower-pod interval increasing curvi-linearly as sites became cooler, with a strong effects between 11 and 16°C, tailing off after 17.5°C, but remaining statistically significant. There is little useful variation for chilling tolerance within domesticated chickpea. Small, albeit statistically significant differences in pod set delay in chickpea collected from contrasting flowering phase habitats, were marginal compared to more tolerant species such as Cicer bijugum, Cicer judaicum and L. angustifolius, and to a lesser extent Cicer reticulatum, Cicer pinnatifidum, and Cicer echinospermum. No differences were observed between desi and kabuli types. Field screening identified robust chilling tolerance in a C. echinospermum accession that commenced podding earlier, at lower temperatures (10.0°C), and yielded 5 times more than Rupali, the most productive chickpea. Controlled temperature experiments confirmed that in contrast to chickpea, pollen germination, viability, frequency on the stigma surface and subsequent pod set were unaffected by low post-anthesis temperatures (13/7°C) in C. echinospermum and L. angustifolius. Our results indicate that chickpea is even more chilling sensitive than previously thought. Because C. echinospermum is inter-fertile with chickpea, it has considerable potential both as a donor of robust chilling tolerance and as an agent for investigating resistance mechanisms. [Copyright &y& Elsevier]

Abstract: The button mushroom Agaricus bisporus commercially cultivated requires 16–19°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°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°C. [Copyright &y& Elsevier]

Quantitative evaluation of phytochemical diversity in Adhatoda vasica Nees populations from five different ecogeographical regions was performed using a highly sensitive, robust and economic high performance thin layer chromatography (HPTLC) procedure. The method was validated for specificity, precision and accuracy as per the guidelines affirmed by International Conference on Harmonization of technical requirements for registration of pharmaceuticals for human use (ICH). The findings support the existence of distinct natural chemotypes within the species. Two out of the five regions had about three times higher mean vasicine content than the remaining three regions. The comparative phytochemical fingerprint profiles were quite similar except for the concentration variation seen for different alkaloids. As the quinazoline alkaloids are the biologically active compounds in A. vasica, the samples that accumulate high levels of alkaloids seem to be promising for further propagation. [ABSTRACT FROM AUTHOR]