A comprehensive phylogeny of extinct and extant Rhizomyinae (Rodentia): evidence for multiple intercontinental dispersals

The subfamily Rhizomyinae is known from the Late Oligocene up to the present. Today this group comprises six species, which live in southern Asia and eastern Africa. Despite the current moderate diversity of the rhizomyines, they had a greater diversification and wider distribution in the past: from Asia, their land of origin, to Africa, which they entered during the Early Miocene. So far 33 fossil species can be referred to this group. A cladistic analysis involving fossil and living species has been carried out. Prokanisamys spp. turned out to be the most basal taxa of the ingroup. This analysis calls into question the monophyly of several genera, and allows the proposal of a phylogenetic definition of the tribes Tachyoryctini and Rhizomyini. It also provides information about the origin of the African rhizomyines and allows inferring multiple dispersal phenomena from Asia to Africa in Early and Late Miocene times.     

On the phylogeny and evolution of Mesozoic and extant lineages of Adephaga (Coleoptera,Insecta)

The relationships of extant and extinct lineages of Adephaga were analysed formally for the first time. Emphasis is placed on the aquatic and semiaquatic groups and their evolution in the Mesozoic. ?Triadogyrus and ?Mesodineutus belong to Gyrinidae, the sister group of the remaining families. ?Triaplidae are the sister group of the following groups (Haliplidae, Geadephaga, Dytiscoidea incl. ?Liadytidae, ?Parahygrobiidae and ?Coptoclavidae [major part]). The lack of a ventral procoxal joint and a very short prosternal process are plesiomorphies of ?Triaplidae. ?Coptoclavidae and ?Timarchopsinae are paraphyletic. ?Timarchopsis is placed in a geadephagan clade. In contrast to other coptoclavids, its metathorax is close to the condition found in Haliplidae, with a complete transverse ridge and coxae with large plates and free mesal walls. ?Coptoclavidae s.str., i.e. excl. ?Timarchopsis, is a dytiscoid subgroup. The mesal metacoxal walls are fused, the coxal plates are reduced, and the transverse ridge is absent. ?Stygeonectes belongs to this dytiscoid coptoclavid unit and is therefore misplaced in ?Timarchopsinae. ?Liadytidae belongs to a dytiscoid subgroup, which also comprises the extant families Aspidytidae, Amphizoidae, Hygrobiidae and Dytiscidae. ?Parahygrobia is the sister group of Hygrobiidae. The larvae are characterized by a broad gula, the absence of the lacinia, retractile maxillary bases and very long urogomphi set with long setae. ?Liadytiscinae is the sister group of extant Dytiscidae. There is no support for a clade ?Eodromeinae and for Trachypachidae incl. ?Eodromeinae. ?Fortiseode is nested within Carabidae. The exclusion of fossil taxa has no effect on the branching pattern. The evolution of Adephaga in the Mesozoic is discussed. Possible reasons for the extinction of ?Coptoclavidae are the rise of teleost fish and the competition of Gyrinidae and Dytiscidae, which possess efficient defensive glands and larval mandibular sucking channels.     

Chiral Separation of the Clinically Important Compounds Fucose and Pipecolic Acid Using CE: Determination of the Most Effective Chiral Selector

In this study, simple electrophoretic methods were developed for the chiral separation of the clinically important compounds fucose and pipecolic acid. In recent years, these analytes, and particularly their individual enantiomers, have attracted considerable attention due to their role in biological functions and disorders. The detectability and sensitivity of pipecolic acid and fucose were improved by reacting them with fluorenylmethyloxycarbonyl chloride (FMOC‐Cl) and 5‐amino‐2‐naphthalene‐sulfonic acid (ANSA), respectively. The enantioseparation conditions were optimized by initially investigating the type of the chiral selector. Different chiral selectors, such as polymeric surfactants and cyclodextrins, were used and the most effective ones were determined with regard to resolution and analysis time. A 10‐mM β‐cyclodextrin was able to separate the enantiomers of ANSA‐DL‐fucose and the polymeric surfactant poly(sodium N‐undecanoyl‐LL‐leucine‐valinate) was able to separate the enantiomers of FMOC‐DL‐pipecolic acid, with resolution values of 3.45 and 2.78, respectively. Additional parameters, such as the concentration and the pH of the background electrolyte (BGE), the concentration of the chiral selector, and the addition of modifiers were examined in order to optimize the separations. The addition of the chiral ionic liquid D‐alanine tert‐butyl ester lactate into the BGE was also investigated, for the first time, in order to improve resolution of the enantiomers. Chirality 25:556–560, 2013. © 2013 Wiley Periodicals, Inc.     

Revising the Absolute Configurations of Coatlines via Density Functional Theory Calculations of Electronic Circular Dichroism Spectra

Coatline A ( 1 ) and α‐epi‐coatline A ( 4 ) co‐occur in the trunk extract of Andira coriacea. Inspection of their chiroptical properties led to intriguing results. After a careful examination of the experimental data used for the previously reported absolute configuration of these compounds, some uncertainties were identified. A combined theoretical approach including conformational analyses and calculation of electronic circular dichroism (ECD) spectra, in addition with experimental data obtained for schoepfin A ( 5 ) and the new schoepfin D ( 6 ) isolated from Senna quinquangulata, allowed the revision of the absolute configuration of coatlines A ( 1 ) and B ( 2 ). Chirality 25:180–184, 2013. © 2012 Wiley Periodicals, Inc.     

Asymmetric Allylation of α‐Ketoester‐Derived N‐Benzoylhydrazones Promoted by Chiral Sulfoxides/N‐Oxides Lewis Bases: Highly Enantioselective Synthesis of Quaternary α‐Substituted α‐Allyl‐α‐Amino Acids

Chiral sulfoxides/N‐oxides (R)‐ 1 and (R,R)‐ 2 are effective chiral promoters in the enantioselective allylation of α‐keto ester N‐benzoylhydrazone derivatives 3a , 3b , 3c , 3d , 3e , 3f , 3g to generate the corresponding N‐benzoylhydrazine derivatives 4a , 4b , 4c , 4d , 4e , 4f , 4g , with enantiomeric excesses as high as 98%. Representative hydrazine derivatives 4a , 4b were subsequently treated with SmI₂, and the resulting amino esters 5a , 5b with LiOH to obtain quaternary α‐substituted α‐allyl α‐amino acids 6a , 6b , whose absolute configuration was assigned as (S), with fundament on chemical correlation and electronic circular dichroism (ECD) data. Chirality 25:529–540, 2013. © 2013 Wiley Periodicals, Inc.     

Stereoselective Accumulation of Propranolol Enantiomers in K562 and K562/ADR Cells

The stereoselective uptake of propranolol enantiomers was investigated by using the K562 and K562 adriamycin‐resistant cell line (K562/ADR) as a model. An enantioselective RP‐HPLC method was applied to determine the accumulation of propranolol (PPL) stereoisomers in K562 and K562/ADR cells. The concentration, time and temperature dependent studies showed that the accumulation of S‐(?)‐PPL was higher than R‐(+)‐PPL in K562 cells and uptake of R‐(+)‐PPL was significantly higher than that of S‐(?)‐PPL in K562/ADR cells. The results indicate the enantioselective accumulation of propranolol enantiomers in K562 and K562 / ADR cells. Chirality 25:361–364, 2013. © 2013 Wiley Periodicals, Inc.     

How do low dispersal species establish large range sizes? The case of the water beetle Graphoderus bilineatus

Species’ dispersal abilities have been considered a major driving force in establishment and maintenance of large range sizes. However, recent studies question the general validity of this relationship because the relationship between dispersal ability and range size might in some cases be less important than species phylogeny or local spatial attributes. In this study we used the water beetle Graphoderus bilineatus a philopatric species of conservation concern in Europe as a model to explain large range size and to support effective conservation measures for such species that also have limited dispersal. We recorded the presence/absence of G. bilineatus and measured 14 habitat and 20 landscape variables at 228 localities in Estonia, Poland and Sweden within the core range of the species. Using information theory and average multivariate logistic regression models we determined that presence of G. bilineatus depended on landscape connectivity, distance to a possible source habitat, and stability of the site; however, specificity of habitat characteristics was not vital for the species. We reason that the large range of G. bilineatus is best explained by the historical combination of lakes, river systems and wetlands which used to be highly connected throughout the central plains of Europe. Our data suggest that a broad habitat niche can prevent landscape elements from becoming barriers for species like G. bilineatus. Therefore, we question the usefulness of site protection as conservation measures for G. bilineatus and similar philopatric species. Instead, conservation actions should be focused at the landscape level to ensure a long‐term viability of such species across their range.     

Home range,activity and sociality of a top predator,the dingo: a test of the Resource Dispersion Hypothesis

The idea that groups of individuals may develop around resource patches led to the formulation of the Resource Dispersion Hypothesis (RDH). We tested the predictions of the RDH, within a quasi‐experimental framework, using Australia’s largest terrestrial predator, the dingo Canis lupus dingo. Average dingo group sizes were higher in areas with abundant focal food sources around two mine sites compared with those in more distant areas. This supports the notion that resource richness favours larger group size, consistent with the RDH. Irrespective of season or sex, average home range estimates and daily activity for dingoes around the mine sites were significantly less than for dingoes that lived well away. Assuming that a territory is the defended part of the home range and that territory size is correlated with home range size, consistent with the RDH, the spatial dispersion of food patches therefore determined territory size for dingoes in our study. However, although sample size was small, some dingoes that accessed the supplementary food resource at the mines also spent a large proportion of their time away, suggesting a breakdown of territorial defence around the focal food resource. This, in combination with the large variation in home range size among dingoes that accessed the same supplementary food resource, limits the predictive capabilities of the RDH for this species. We hypothesize that constraints on exclusive home range occupancy will arise if a surfeit of food resources (in excess of requirements for homeostasis) is available in a small area, and that this will have further effects on access to mates and social structure. We present a conceptual model of facultative territorial defence where focal resources are available to demonstrate our findings.     

Ecologically based definition of seasons clarifies predator–prey interactions

Species interactions within food webs are driven by multiple constraints, including those imposed by seasonal changes in the environment. Ecologically sound definitions of seasons may therefore be a prerequisite for clarifying predator prey interactions. Most studies define biological seasons based on fixed schedules or on temporal changes in a single movement measurement. We used a novel clustering approach based on homogeneous space‐use patterns of GPS‐collared animals to reveal 7 biological seasons for caribou Rangifer tarandus caribou, and 5 for both moose Alces alces and grey wolves Canis lupus interacting in a boreal ecosystem. Subsequent evaluation of niche overlap showed that, as predicted, wolves had a stronger spatio‐temporal connection with moose, its main prey, than with caribou. Movement constraints and limiting resource distributions similarly affected all species in some instances, but also caused temporal changes in the extent of niche overlap between wolves and its two prey. The risk that caribou faced was not only linked to the niche overlap with wolves, but also to the extent of wolf‐moose niche overlap during the same period. Food‐web properties emerged from the analysis, with temporal changes in relative niche overlap reflecting the strength of trophic interactions during the year. Our study demonstrates how the study of trophic interactions can benefit from comprehensive definitions of biological seasons.     

Divergent host phenotypes create opportunities and constraints on the distribution of two wing‐dwelling feather mites

The diversity of symbionts (commensals, mutualists or parasites) that share the same host species may depend on opportunities and constraints on host exploitation associated with host phenotype or environment. Various host traits may differently influence host accessibility and within‐host population growth of each symbiont species, or they may determine the outcome of within‐host interactions among coexisting species. In turn, phenotypic diversity of a host species may promote divergent exploitation strategies among its symbiotic organisms. We studied the distribution of two feather mite species, Proctophyllodes sylviae and Trouessartia bifurcata, among blackcaps Sylvia atricapilla wintering in southern Spain during six winters. The host population included migratory and sedentary individuals, which were unequally distributed between two habitat types (forests and shrublands). Visual mite counts showed that both mite species often coexisted on sedentary blackcaps, but were seldom found together on migratory blackcaps. Regardless of host habitat, Proctophyllodes were highly abundant and Trouessartia were scarce on migratory blackcaps, but the abundance of both mite species converged in intermediate levels on sedentary blackcaps. Coexistence may come at a cost for Proctophyllodes, whose load decreased when Trouessartia was present on the host (the opposite was not true). Proctophyllodes load was positively correlated with host wing length (wings were longer in migratory blackcaps), while Trouessartia load was positively correlated to uropygial gland size (sedentary blackcaps had bigger glands), which might render migratory and sedentary blackcaps better hosts for Proctophyllodes and Trouessartia, respectively. Our results draw a complex scenario for mite co‐existence in the same host species, where different mite species apparently take advantage of, or are constrained by, divergent host phenotypic traits. This expands our understanding of bird–mite interactions, which are usually viewed as less dynamic in relation to variation in host phenotype, and emphasizes the role of host phenotypic divergence in the diversification of symbiotic organisms.