A framework for the identification of hotspots of climate change risk for mammals

As rates of global warming increase rapidly, identifying species at risk of decline due to climate impacts and the factors affecting this risk have become key challenges in ecology and conservation biology. Here, we present a framework for assessing three components of climate‐related risk for species: vulnerability, exposure and hazard. We used the relationship between the observed response of species to climate change and a set of intrinsic traits (e.g. weaning age) and extrinsic factors (e.g. precipitation seasonality within a species geographic range) to predict, respectively, the vulnerability and exposure of all data‐sufficient terrestrial non‐volant mammals (3,953 species). Combining this information with hazard (the magnitude of projected climate change within a species geographic range), we identified global hotspots of species at risk from climate change that includes the western Amazon basin, south‐western Kenya, north‐eastern Tanzania, north‐eastern South Africa, Yunnan province in China, and mountain chains in Papua‐New Guinea. Our framework identifies priority areas for monitoring climate change effects on species and directing climate mitigation actions for biodiversity.     

Genetic Evidence for the Allodiploid Origin of the Moss Species Polytrichum longisetum

Abstract: Fixed heterozygous banding patterns observed for 4 allozyme and 12 microsatellite loci, in combination with a chromosome number of 14, show that Polytrichum longisetum is an allodiploid species. Comparison of these banding patterns with those of related Polytrichaceae species suggest that Polytrichum formosum, or an ancestor taxon of this species, is one of the haploid progenitors of P. longisetum. The second progenitor species of P. longisetum could not be designated in this study as it was not among the examined possible progenitor species. DNA sequence data for two microsatellite loci, however, suggest that the second progenitor species should possibly be more closely related to P. formosum than any of the other haploid possible progenitor species examined in this study. As the current systematic literature does not mention the existence of such a species, this could indicate that the second progenitor species is already extinct.     

Support for the predictions of the pollinator-mediated stabilizing selection hypothesis

Aims Floral traits are frequently used in traditional plant systematics because of their assumed constancy. One potential reason for the apparent constancy of flower size is that effective pollen transfer between flowers depends on the accuracy of the physical fit between the flower and pollinator. Therefore, flowers are likely to be under stronger stabilizing selection for uniform size than vegetative plant parts. Moreover, as predicted by the pollinator-mediated stabilizing selection (PMSS) hypothesis, an accurate fit between flowers and their pollinators is likely to be more important for specialized pollination systems as found in many species with bilaterally symmetric (zygomorphic) flowers than for species with radially symmetric (actinomorphic) flowers.Methods In a comparative study of 15 zygomorphic and 13 actinomorphic species in Switzerland, we tested whether variation in flower size, among and within individuals, is smaller than variation in leaf size and whether variation in flower size is smaller in zygomorphic compared to actinomorphic species.Important findings Indeed, variation in leaf length was significantly larger than variation in flower length and width. Within-individual variation in flower and leaf sizes did not differ significantly between zygomorphic and actinomorphic species. In line with the predictions of the PMSS, among-individual variation in flower length and flower width was significantly smaller for zygomorphic species than for actinomorphic species, while the two groups did not differ in leaf length variation. This suggests that plants with zygomorphic flowers have undergone stronger selection for uniform flowers than plants with actinomorphic flowers. This supports that the relative uniformity of flowers compared to vegetative structures within species, as already observed in traditional plant systematics, is, at least in part, a consequence of the requirement for effective pollination.     

Use of biotechnologies for the conservation of plant biodiversity

In vitro techniques are very useful for conserving plant biodiversity, including (a) genetic resources of recalcitrant seed and vegetatively propagated species, (b) rare and endangered plant species and (c) biotechnology products such as elite genotypes and genetically engineered material. Explants from recalcitrant seed and vegetatively propagated species can be efficiently collected under field conditions using in vitro techniques. In vitro culture techniques ensure the production and rapid multiplication of disease-free material. Medium-term conservation is achieved by reducing growth of plant material, thus increasing intervals between subcultures. For long-term conservation, cryopreservation (liquid nitrogen, −196°C) allows storing plant material without modification or alteration for extended periods, protected from contaminations and with limited maintenance. Slow growth storage protocols are routinely employed for a large number of species, including numerous endangered plants, from temperate and tropical origin. Cryopreservation is well advanced for vegetatively propagated species, and techniques are ready for large-scale experimentation in an increasing number of cases. Research is much less advanced for recalcitrant species due to their seed characteristics, viz., very high sensitivity to desiccation, structural complexity and heterogeneity in terms of developmental stage and water content at maturity. However, various technical approaches should be explored to develop cryopreservation techniques for a larger number of recalcitrant seed species. A range of analytical techniques are available, which allow understanding physical and biological processes taking place in explants during cryopreservation. These techniques are extremely useful to assist in the development of cryopreservation protocols. In comparison with crop species, only limited research has been performed on cryopreservation of rare and endangered species. Even though routine use of cryopreservation is still limited, an increasing number of examples where cryopreservation is used on a large scale can be found both in genebanks for crops and in botanical gardens for endangered species.     

A note on a code for the identification of the 'viridans' streptococci

A simple numerical code for the identification of 'viridans' streptococci was devised with Facklam's system of classification. This is based on biochemical criteria and consists of nine tests, with an additional five for the identification of closely related species and the subspecies or biotype of Streptococcus mutans. The 'viridans' streptococci can be divided into 10 species with the aid of this scheme while five subspecies and an additional biotype of Streptococcus mutans can be recognized. Advantages of this scheme are that the numerical code differentiates between isolates of the same species, distinguishes between biochemically active and non-active species and indicates similarities between species.     

A note on a code for the identification of the 'viridans' streptococci

A simple numerical code for the identification of 'viridans' streptococci was devised with Facklam's system of classification. This is based on biochemical criteria and consists of nine tests, with an additional five for the identification of closely related species and the subspecies or biotype of Streptococcus mutans. The 'viridans' streptococci can be divided into 10 species with the aid of this scheme while five subspecies and an additional biotype of Streptococcus mutans can be recognized. Advantages of this scheme are that the numerical code differentiates between isolates of the same species, distinguishes between biochemically active and non-active species and indicates similarities between species.     

Application of species richness estimators for the assessment of fungal diversity

Species richness and distribution patterns of wood-inhabiting fungi and mycetozoans (slime moulds) were investigated in the canopy of a Central European temperate mixed deciduous forest. Species richness was described with diversity indices and species-accumulation curves. Nonmetrical multidimensional scaling was used to assess fungal species composition on different tree species. Different species richness estimators were used to extrapolate species richness beyond our own data. The reliability of the abundance-based coverage estimator, Chao, Jackknife and other estimators of species richness was evaluated for mycological surveys. While the species-accumulation curve of mycetozoans came close to saturation, that of wood-inhabiting fungi was continuously rising. The Chao 2 richness estimator was considered most appropriate to predict the number of species at the investigation site if sampling were continued. Gray's predictor of species richness should be used if statements of the number of species in larger areas are required. Multivariate analysis revealed the importance of different tree species for the conservation and maintenance of fungal diversity within forests, because each tree species possessed a characteristic fungal community. The described mathematical approaches of estimating species richness possess great potential to address fungal diversity on a regional, national, and global scale.     

A spider diversity model for the Caucasus Ecoregion

Precise information on spatial patterns of species richness and endemic species distribution is important for effective species conservation. In the Caucasus Ecoregion such information is virtually non-existent for invertebrate taxa. Using occurrence data from a large database we calculated species distribution models with the GARP algorithm for 471 spider species to visualize the diversity distribution of spider species in this region. Overall species diversity was highest in mountain forests of the North Caucasus, east-central Georgia, the southern slopes of the eastern Great Caucasus and south-east Azerbaijan. A regression tree analysis Chi squared automatic interaction detector method revealed the mean temperature of the driest quarter and precipitation parameters to be the main environmental factors shaping these patterns. Diversity of endemic species was correlated with overall species diversity but hotspots of endemic species (10+ percent of all species) exists in high-mountain areas, suggesting post-glacial speciation events in the high mountains as the main sources of high endemism in Caucasus. Further information on the spatial distribution of species diversity of invertebrate taxa in the Caucasus Ecoregion is needed to improve conservation efforts in this biodiversity hotspot.     

A new method for conservation planning for the persistence of multiple species

Although the aim of conservation planning is the persistence of biodiversity, current methods trade-off ecological realism at a species level in favour of including multiple species and landscape features. For conservation planning to be relevant, the impact of landscape configuration on population processes and the viability of species needs to be considered. We present a novel method for selecting reserve systems that maximize persistence across multiple species, subject to a conservation budget. We use a spatially explicit metapopulation model to estimate extinction risk, a function of the ecology of the species and the amount, quality and configuration of habitat. We compare our new method with more traditional, area-based reserve selection methods, using a ten-species case study, and find that the expected loss of species is reduced 20-fold. Unlike previous methods, we avoid designating arbitrary weightings between reserve size and configuration; rather, our method is based on population processes and is grounded in ecological theory.     

福建植物生物多样性的特点及其生物安全问题

对福建植物生物多样性从物种多样性、遗传多样性和生态系统多样性三个层面进行了评价,分析了植物生物多样性的特点。在此基础上提出了影响福建植物生物多样性的主要生物安全问题。研究表明,福建植物生物多样性具有植物种类丰富,热带和亚热带的科属种类多、起源古老,中国特有成分比例较高和国家重点保护植物较为丰富等特点。影响植物生物多样性的主要生物安全问题包括阔叶林面积不断减少,森林资源总体质量下降;濒危野生植物比重增大,名木古树破坏严重;外来物种入侵呈加重趋势。     

A call for an end to calls for the end of invasion biology

Calls for the end of invasion biology are misguided. There is no evidence that modern invasion biology has progressed slowly in its short life. Although some aspects of biological invasions fit comfortably in the framework of ecological succession, many others do not. Some native species, particularly in the wake of various anthropogenic impacts, behave like invasive non‐native species, but the probability and degree of harmful impact are greater for non‐native than for native species. Neither native nor non‐native species suffer lack of attention and research by virtue of the fact that invasion biology focuses on the latter. Basing management solely on current observed impact is highly risky because impacts may be subtle but nonetheless important, and impacts often change, as they are contingent on the physical or biotic environment. The known harmful impacts of many non‐native species suggest that recent introductions warrant attention even if impacts are not evident. Neither is the focus of modern invasion biology on non‐native species motivated by xenophobia. Rather, it reflects the recognition of their likelihood of harmful impact. A related call for the end of traditional restoration ecology shares many features with calls to terminate invasion biology, not least because management of invasive non‐native species is a key component of restoration ecology. Such species are a dominant element in generating the ‘novel ecosystems’ that are said to render traditional restoration ecology obsolete. The argument that both invasion management and traditional restoration are largely futile endeavors is contradicted by substantial and growing successes in both fields.     

Recommendations for Assessing the Effectiveness of Surrogate Species Approaches

Surrogate species approaches, including flagship, focal, keystone, indicator, and umbrella, are considered an effective means of conservation planning. For conservation biologists to apply surrogates with confidence, they must have some idea of the effectiveness of surrogates for the circumstances in which they will be applied. We reviewed tests of the effectiveness of surrogate species planning to see if research supports the development of generalized rules for (1) determining when and where surrogate species are an effective conservation tool and (2) how surrogate species should be selected such that the resulting conservation plan will effectively protect biodiversity or achieve other conservation goals. The context and methods of published studies were so diverse that we could not draw general conclusions about the spatial or temporal scales, or ecosystems or taxonomic groups for which surrogate species approaches will succeed. The science of surrogate species can progress by (1) establishing methods to compare diverse measures of effectiveness; (2) taking advantage of data-rich regions to examine the potential effectiveness of surrogate approaches; (3) incorporating spatial scale as an explanatory variable; (4) evaluating surrogate species approaches at broader temporal scales; (5) seeking patterns that will lead to hypothesis driven research; and (6) monitoring surrogate species and their target species.     

The relevance of fire frequency for the floodplain vegetation of the Okavango Delta, Botswana

The study investigates the relevance of fire frequency for the floodplain vegetation of the Okavango Delta in Botswana, considering species composition, species richness, vegetation structure and tree density. Based on flood and fire frequency data derived from a series of satellite images, active and drying floodplains were separated and study plots were selected with fire frequencies up to ten burns between 1989 and 2003. Both for drying and active floodplains, no typical species assemblage could be associated with fire frequency. On drying floodplains, fire frequency showed no effect on species composition, but rather on vegetation structure. While small woody species showed higher cover values on high fire frequency, large trees showed significantly lower cover values on high fire frequency. For active floodplains, a significant response to fire frequency, both positively and negatively could be determined for specific species. But as almost none of these species appear at low or high frequency only, no differences in species composition could be associated with fire frequency. Rather flood frequency and specific annual flood cycles could be described as the determining factors for the vegetation on active floodplains.     

A test of alternative hypotheses for the evolution of reproductive isolation between spadefoot toads: support for the reinforcement hypothesis

Abstract How do species that interbreed become reproductively isolated? If hybrids are less fit than parental types, natural selection should promote reproductive isolation by favoring the evolution of premating mechanisms that prevent hybridization (a process termed reinforcement). Although reinforcement should generate a decline in hybridization over time, countervailing forces of gene flow and recombination are thought to preclude natural selection from enhancing and finalizing reproductive isolation. Here, I present recent estimates of hybridization frequency between two species of spadefoot toad, Spea multiplicata and S. bombifrons. I compare these recent measures of hybrid frequency with previously published estimates and show that hybridization between these species has declined precipitously over the past 27 years. Although previous studies suggest that reinforcement possibly accounts for this decline in hybrids over time, three alternative hypotheses also can explain the observed decrease in hybridization. First, if one of the two interacting species becomes rare, opportunities for and incidence of hybridization may decrease. Second, if one of the two interacting species is initially rare, hybridization may be initially common if the rare species has difficulty locating conspecific mates. Third, if hybrids are produced only in particular environments, hybrid frequency may decline if habitat changes result in loss of those environments that promote hybrid formation. I found no support for these three alternative explanations of the decline in hybrids. Instead, reinforcement appears to best account for the evolution of enhanced reproductive isolation between these species. Moreover, the finding that hybridization declined precipitously in only 27 years suggests that many systems that have undergone reinforcement may be overlooked because reproductive isolation between the interacting populations or species may already be complete.     

Microsatellite markers for the study of cetacean populations

Microsatellites are one of the most important classes of nuclear genetic markers and offer many advantages for the study of marine mammals. Here we describe the isolation and characterization of 12 cetacean microsatellites which are then tested across 30 different cetacean species. For around half the species tested, five or more polymorphic loci were identified. Since many species were represented by only one or two specimens, this figure is likely to underestimate the usefulness of these markers. No relationship was found between microsatellite repeat length and proportion of species which gave polymorphic products.     

Comparison of four modeling tools for the prediction of potential distribution for non-indigenous weeds in the United States

This study compares four models for predicting the potential distribution of non-indigenous weed species in the conterminous U.S. The comparison focused on evaluating modeling tools and protocols as currently used for weed risk assessment or for predicting the potential distribution of invasive weeds. We used six weed species (three highly invasive and three less invasive non-indigenous species) that have been established in the U.S. for more than 75 years. The experiment involved providing non-U. S. location data to users familiar with one of the four evaluated techniques, who then developed predictive models that were applied to the United States without knowing the identity of the species or its U.S. distribution. We compared a simple GIS climate matching technique known as Proto3, a simple climate matching tool CLIMEX Match Climates, the correlative model MaxEnt, and a process model known as the Thornley Transport Resistance (TTR) model. Two experienced users ran each modeling tool except TTR, which had one user. Models were trained with global species distribution data excluding any U.S. data, and then were evaluated using the current known U.S. distribution. The influence of weed species identity and modeling tool on prevalence and sensitivity effects was compared using a generalized linear mixed model. Each modeling tool itself had a low statistical significance, while weed species alone accounted for 69.1 and 48.5% of the variance for prevalence and sensitivity, respectively. These results suggest that simple modeling tools might perform as well as complex ones in the case of predicting potential distribution for a weed not yet present in the United States. Considerations of model accuracy should also be balanced with those of reproducibility and ease of use. More important than the choice of modeling tool is the construction of robust protocols and testing both new and experienced users under blind test conditions that approximate operational conditions.     

Looking for the gold standard: assessment of the effectiveness of four traps for monitoring mosquitoes in Italy

Several kinds of traps are available for the collection of Culicidae species creating nuisance problems and/or a potential risk of pathogen transmission. The choice of the most appropriate sampling device should take into consideration the objective of the monitoring activity (e.g., faunistic research, vector control evaluation, arbovirus surveillance, etc.), the ecological and behavioral characteristics of the target mosquito species, and the ecology of the sampling areas. However, there are few factual criteria technical personnel can rely on to choose the most suitable sampling method, particularly when the targets are represented by mosquito species in temperate areas. We carried out a Latin square experiment in three ecologically different settings in Mantua municipality (northern Italy) to compare the performance of four different traps targeting host-seeking mosquitoes: two traps specifically designed for mosquito monitoring purposes (Centers for Disease Control and Prevention CO(2) trap and Biogents BG Eisenhans de Luxe trap) and two designed to reduce mosquito densities in outdoor domestic settings (Activa Acti Power Trap PV 440 and Activa Acti Power Trap MT 250 Plus). Overall, 1,930 specimens belonging to nine species were collected and differences in the performance of the four traps with reference to their ability to detect overall species diversity, as well as to collect single species, were highlighted. These observations, coupled with an analysis of the costs associated with the trap's purchase, operation, and servicing, provide useful indications for the implementation of mosquito monitoring in temperate areas.     

Development of species-specific PCR primer sets for the detection of Leptospira

Spirochetes of the genus Leptospira infect animals and humans and are the causative agents for the emerging infectious disease leptospirosis. Rapid and simple assays for the identification of individual Leptospira species are currently not available. For identification of individual Leptospira species, PCR primers that detect the ompL1 gene sequence for the majority of pathogenic leptospires were developed in this study. The primer pairs detect Leptospira interrogans, Leptospira borgpetersenii, Leptospira kirschneri, Leptospira santarosai, Leptospira weilii and Leptospira noguchii, without cross-reacting with other Leptospira species. The development of the primers revealed a divergence of the ompL1 gene within L. interrogans, splitting this species into two separate groups. The species-specific primers will be especially useful in epidemiological studies and disease outbreak investigations for the detection of Leptospira species in human, animal and environmental samples.     

A FAFLP system for the improved identification of plant-pathogenic and plant-associated species of the genus Pantoea

The majority of Pantoea species are either plant-pathogenic or plant-associated and cause a wide variety of symptoms on a range of hosts. Identification of Pantoea species is difficult due to minor differences in phenotypic characteristics between them and related Enterobacteriaceae. Fluorescent amplified fragment length polymorphism (FAFLP) analysis was investigated for use as a rapid, molecular-based identification technique to the species level of the genus Pantoea. Following analysis of the band patterns generated by FAFLP, seven distinct clusters were observed, one for each validly published species of the genus. FAFLP has proven to be a rapid, reproducible identification technique for all species of the genus Pantoea.     

Criteria for the identification of potential colonizers*

Man's interference with the environment encourages colonization by species that are often undesirable, hence a technique by which potential colonizers can be identified is urgently required. It can be developed when general prerequisites for successful colonization are identified. These prerequisites can then serve as criteria to distinguish potential colonizers from non-colonizers. The proposed relevant prerequisites are associated with two problems encountered by all colonists: small founding populations and a difference in the environmental conditions between the source area and the target, making the target rather unpredictable. Both these features increase the risk of random extinction, which can be overcome by possessing a potential for rapid population growth (high r) and for rapid adaptation to environmental conditions (high genetic variability). The parameters associated with meeting these prerequisites can serve for the identification of potential colonizers and for ranking species as to their colonization ability. The proposed technique may best be tested by comparing the intrinsic growth rate and the electrophoretic variability of species that have recently colonized with closely related species that have not done so under similar circumstances. The colonization of the eastern Mediterranean by Red Sea species immigrating via the Suez Canal created an appropriate system for such a test.