Ecological comparisons between Eastern Asia and North America: historical and geographical perspectives

The close floristic affinities between eastern Asia and North America have long been recognized and intensively studied, however, the ecological and biogeographical consequences of such a floristic relationship between these two remotely separated regions has been largely neglected until recently. Quantitative investigations of such relationships could greatly improve our understanding of many global and historical aspects of species diversity, vegetation dynamics, and biogeography, especially with the rapid developments of cladistic methods of phylogenetic reconstruction. All comparisons and predictions will depend on understanding past and present physical and biological processes (i.e. geological history of the continents and the evolutionary history of organisms), as well as human impacts in both regions. Both species level (life history characteristics, distribution, ecological functions) and community level (species composition, structure, endemism) variables should be investigated. Comparisons should be conducted spatially across vegetation zones and temporally through geological episodes. Emphases on the phylogeny and geological history of component taxa by analysing and synthesizing multidisciplinary data would be helpful, especially with regard to the current trends in global climate change. Diversity measured on different scales (i.e. α-, β, and g-diversity) could provide invaluable information about local-regional relationships and their ecological implications in continental or even global biodiversity patterns.     

Human relaxin-2: historical perspectives and role in cancer biology

One of the most recognised and studied family of peptide hormones is the insulin superfamily. Within this family is the relaxin subfamily which comprises seven members: relaxin-1, -2 and -3 and insulin-like peptides 3, 4, 5 and 6. Besides exhibiting sequence similarities, each member exists as an active A-B heterodimer linked by three disulfide bonds. This mini-review is divided into three broad themes: an overview of all insulin superfamily members (including structural similarities); roles of each superfamily member and finally, a focus on the pleiotropic peptide hormone, human relaxin-2. In addition to promoting vasodilatory effects leading to evaluation in Phase III clinical trials for the treatment of acute heart failure, relaxin has recently been shown to be highly expressed by cancer cells, aiding in their proliferation, invasiveness and metastasis. These contrary effects of relaxin are discussed together with current efforts in the development of relaxin antagonists that may possess future therapeutic potential for the treatment of certain cancers.     

Convergence and historical effects in harvester ant assemblages of Australia, North America, and South America

In this paper I examine the extent to which contemporary ecological patterns in 42 harvester ant assemblages of three continents can be explained as a result of present-day environments or from differences in the history of each ant biota. The contribution of each factor to the overall variability of six community characters was evaluated by the ANOVA procedure. The mediod revealed absence of convergence in three-continent and pairwise-continent analyses in almost every community attribute that was measured. Significant convergence was detected only in die foraging score for the North America-South America comparison. This implies mat the foraging mode used by ants for searching seeds is more similar within similar environments in the two continents than between different environments in the same continent. Significant historical effects were much more prevalent than convergence both in three-continent and pairwise-continent comparisons. Abundance at baits, body size, and foraging distance were more variable within similar environments in different continents than between different environments in the same continent. The overall absence of convergence documented in this study suggests that constraints related to the evolutionary history of each species assemblage have inhibited convergent evolution in response to local selective pressures.     

Systems biology approaches in cell signaling research

The use of methods for global and quantitative analysis of cells is providing new systems-level insights into signal transduction processes. Recent studies reveal important information about the rates of signal transmission and propagation, help establish some general regulatory characteristics of multi-tiered signaling cascades, and illuminate the combinatorial nature of signaling specificity in cell differentiation.     

The Physiological Ecology of the Zebra Mussel, Dreissena polymorpha, in North America and Europe

SYNOPSIS. The zebra mussel, Dreissena polymorpha (Pallas), wasintroduced into North America in 1986. Initial North American(N.A.) studies suggested that physiological responses variedbetween N.A. and European populations. However, literature reviewindicates agreement on most aspects of physiological adaptationincluding: respiratory responses; hypoxia/anoxia tolerance;salinity limits; emersion tolerance; freezing resistance; environmentalpH limits; calcium limits; starvation responses; and bioenergeticpartitioning. The main differences among N.A. and European musselsappear to be elevated upper thermal limits and temperaturesfor optimum growth among N.A. populations. N.A. zebra musselsprobably originated from the northern shore of the Black Seain the warmest portion of the mussel's European range. However,most European physiological data come from northern Europe wherepopulations may be adapted to colder temperatures. Alternatively,N.A. research suggests that mussels may have a capacity forseasonal temperature acclimatization such that responses recordedin warmer N.A. waters may be different from those recorded innorthern Europe even after short-term laboratory acclimation.Studies of genetic variation and physiological response amongEuropean and N.A. D. polymorpha populations are required toelucidate the basis for physiological differentiation. Recentlyevolved D. polymorpha has poor resistance adaptations comparedto unionacean and sphaeriid bivalves with longer freshwaterfossil histories. Poor resistance adaptations make it less suitedfor stable habitats, instead, its high fecundities, early maturity,and rapid growth are adaptations to unstable habitats whereextensive resistance adaptations are of little value.     

Contemporary status of the North American paddlefish, Polyodon spathula

North American paddlefish, Polyodon spathula, were once abundant in most large rivers and tributaries of the Mississippi River basin, but numbers have declined dramatically in most areas during the past 100 years. Habitat destruction and river modification are the most obvious changes affecting their distribution and abundance. Although peripheral range has dwindled, paddlefish still occur over most of their historic range and are still found in 22 states. Populations are currently increasing in 3 states, stable in 14, declining in 2, unknown in 3, and extirpated in 4. Sport harvests presently occur in 14 states, however two states with traditionally important sport fisheries report decreased recruitment into the population and are planning more restrictive regulations. Commercial fisheries are reported in only six states. During the past 10 years, five states have removed paddlefish from their commercial list primarily because of declines in adult stocks due to overfishing or illegal fishing. Ten states are currently stocking paddlefish to supplement existing populations or to recover paddlefish populations in the periphery of its native range.     

Status and management of Atlantic sturgeon, Acipenser oxyrinchus, in North America

The Atlantic sturgeon, Acipenser oxyrinchus, consists of two subspecies distributed along the Atlantic coast of North America from Labrador to the east coast of Florida (Atlantic sturgeon subspecies – A. o. oxyrinchus) and along the Gulf of Mexico from Florida Bay, Florida to the mouth of the Mississippi River (Gulf sturgeon subspecies – A. o. desotoi). The species has been exploited throughout its range with landings peaking around the turn of the 20th century followed by drastic declines shortly thereafter. During recent years, landings in Canadian waters have increased substantially (approximately 129 metric tons in 1993) while in the United States landings are more controlled or prohibited (approximately 22–24 metric tons in 1993). Recently, the Atlantic States Marine Fisheries Commission developed a Fishery management plan for Atlantic sturgeon, and the United States Fish & Wildlife Service and Gulf States Marine Fisheries Commission drafted a Gulf Sturgeon Recovery/Management Plan. Fishery managers in Canada are in the process of establishing more stringent fishery regulations for sturgeon. Thus, the impact on populations due to harvesting should be substantially reduced. Current research focus includes: life history and population status studies, stock delineation, and development of culture and stock enhancement techniques. Implementation of the findings of such studies may be helpful in the restoration of depleted stocks.     

The Phylogenetics and Ecology of the Orthopoxviruses Endemic to North America

The data presented herein support the North American orthopoxviruses (NA OPXV) in a sister relationship to all other currently described Orthopoxvirus (OPXV) species. This phylogenetic analysis reaffirms the identification of the NA OPXV as close relatives of “Old World” (Eurasian and African) OPXV and presents high support for deeper nodes within the Chordopoxvirinae family. The natural reservoir host(s) for many of the described OPXV species remains unknown although a clear virus-host association exists between the genus OPXV and several mammalian taxa. The hypothesized host associations and the deep divergence of the OPXV/NA OPXV clades depicted in this study may reflect the divergence patterns of the mammalian faunas of the Old and New World and reflect a more ancient presence of OPXV on what are now the American continents. Genes from the central region of the poxvirus genome are generally more conserved than genes from either end of the linear genome due to functional constraints imposed on viral replication abilities. The relatively slower evolution of these genes may more accurately reflect the deeper history among the poxvirus group, allowing for robust placement of the NA OPXV within Chordopoxvirinae. Sequence data for nine genes were compiled from three NA OPXV strains plus an additional 50 genomes collected from Genbank. The current, gene sequence based phylogenetic analysis reaffirms the identification of the NA OPXV as the nearest relatives of “Old World” OPXV and presents high support for deeper nodes within the Chordopoxvirinae family. Additionally, the substantial genetic distances that separate the currently described NA OPXV species indicate that it is likely that many more undescribed OPXV/NA OPXV species may be circulating among wild animals in North America.     

The current status of ethnobiological research in Latin America: gaps and perspectives

Background

Recent reviews have demonstrated an increase in the number of papers on ethnobiology in Latin America. Among factors that have influenced this increase are the biological and cultural diversity of these countries and the general scientific situation in some countries. This study aims to assess the panorama of ethnobiological research in Latin America by analyzing its evolution, trends, and future prospects.

Methods

To conduct this study, we searched for papers in the Scopus (http://www.scopus.com) and Web of Science (http://www.isiknowledge.com) databases. The search was performed using combinations of keywords and the name of each Latin American country. The following countries were included in this study: Argentina, Bolivia, Brazil, Chile, Colombia, Costa Rica, Cuba, Ecuador, Guatemala, Haiti, Honduras, Mexico, Panama, Paraguay, Peru, Venezuela, and Uruguay.

Results and conclusions

According to our inclusion criteria, 679 ethnobiological studies conducted in Latin America were found for the period between 1963 and 2012. Of these studies, 289 (41%) were conducted in Brazil, 153 in Mexico (22%), 61 in Peru (9%), 58 in Argentina (8%), 45 in Bolivia (6%), and 97 (14%) in other Latin American countries. The increased number of publications related to this area of knowledge in recent years demonstrates the remarkable growth of ethnobiology as a science. Ethnobiological research may be stimulated by an increase in the number of scientific events and journals for study dissemination and by the creation of undergraduate courses and graduate programs to train ethnoscientists who will produce high-quality studies, especially in certain countries.

     

Science priorities for seamounts: research links to conservation and management

Seamounts shape the topography of all ocean basins and can be hotspots of biological activity in the deep sea. The Census of Marine Life on Seamounts (CenSeam) was a field program that examined seamounts as part of the global Census of Marine Life (CoML) initiative from 2005 to 2010. CenSeam progressed seamount science by collating historical data, collecting new data, undertaking regional and global analyses of seamount biodiversity, mapping species and habitat distributions, challenging established paradigms of seamount ecology, developing new hypotheses, and documenting the impacts of human activities on seamounts. However, because of the large number of seamounts globally, much about the structure, function and connectivity of seamount ecosystems remains unexplored and unknown. Continual, and potentially increasing, threats to seamount resources from fishing and seabed mining are creating a pressing demand for research to inform conservation and management strategies. To meet this need, intensive science effort in the following areas will be needed: 1) Improved physical and biological data; of particular importance is information on seamount location, physical characteristics (e.g. habitat heterogeneity and complexity), more complete and intensive biodiversity inventories, and increased understanding of seamount connectivity and faunal dispersal; 2) New human impact data; these shall encompass better studies on the effects of human activities on seamount ecosystems, as well as monitoring long-term changes in seamount assemblages following impacts (e.g. recovery); 3) Global data repositories; there is a pressing need for more comprehensive fisheries catch and effort data, especially on the high seas, and compilation or maintenance of geological and biodiversity databases that underpin regional and global analyses; 4) Application of support tools in a data-poor environment; conservation and management will have to increasingly rely on predictive modelling techniques, critical evaluation of environmental surrogates as faunal "proxies", and ecological risk assessment.     

Aggression and violence: perspectives on integrating animal and human research approaches

Aggression and violence are concerns that engage us across society as moral and cultural issues. They are also critical issues for mental health research--both for survivors and for understanding how such behaviors occur. Interpersonal violence often explodes in deliberate acts of physical force leaving survivors behind with a diminished sense of control that is often shadowed by persistent fear and anxiety. The treatment of the victims is a clear and immediate concern; from their perspectives the medical consequences require effective attention whether they suffered as a result of acts of nature, mental disease, ideology, or combinations of these. At the same time preventing violent behavior from happening in the first place is a compelling challenge for public health research.     

Scrapie: uncertainties, biology and molecular approaches

The study of the biology of scrapie in sheep is irretrievably associated with the genetics of the PrP gene in sheep. Control of susceptibility and resistance is so closely linked to certain alleles of the sheep PrP gene that no review on scrapie can avoid PrP genetics. Before the importance of PrP protein was discovered and before the influence of the gene itself on disease incidence was understood, it was clear there were some sheep which were more susceptible to natural scrapie than others and that this feature was heritable. These early observations have led to the development and use of PrP genotyping in sheep in what is probably the biggest genetic selection process ever attempted. The accompanying increase in surveillance has also discovered a novel type of scrapie, the subject of much speculation about its origin.     

Ecology of plant dioecy in the intermountain region of Western North America and California

Summary Data from 44 plant communities of the arid zone of western North America and from the entire California flora suggest that the dioecious habit (separate sexed individuals) is best developed among wind pollinated woody plants. A rationale is presented for the ways in which wind pollination and large plant size have favored the development of the dioecious habit. Based upon the patterns examined, it is concluded that inbreeding depression alone is insufficient to account for the evolution of the dioecious habit in many temperate species.