Cupiennin 1a, an antimicrobial peptide from the venom of the neotropical wandering spider Cupiennius salei, also inhibits the formation of nitric oxide by neuronal nitric oxide synthase

Cupiennin 1a (GFGALFKFLAKKVAKTVAKQAAKQGAKYVVNKQME-NH2) is a potent venom component of the spider Cupiennius salei. Cupiennin 1a shows multifaceted activity. In addition to known antimicrobial and cytolytic properties, cupiennin 1a inhibits the formation of nitric oxide by neuronal nitric oxide synthase at an IC50 concentration of 1.3 +/- 0.3 microM. This is the first report of neuronal nitric oxide synthase inhibition by a component of a spider venom. The mechanism by which cupiennin 1a inhibits neuronal nitric oxide synthase involves complexation with the regulatory protein calcium calmodulin. This is demonstrated by chemical shift changes that occur in the heteronuclear single quantum coherence spectrum of 15N-labelled calcium calmodulin upon addition of cupiennin 1a. The NMR data indicate strong binding within a complex of 1 : 1 stoichiometry.     

Latitude, elevational climatic zonation and speciation in New World vertebrates

Many biodiversity hotspots are located in montane regions, especially in the tropics. A possible explanation for this pattern is that the narrow thermal tolerances of tropical species and greater climatic stratification of tropical mountains create more opportunities for climate-associated parapatric or allopatric speciation in the tropics relative to the temperate zone. However, it is unclear whether a general relationship exists among latitude, climatic zonation and the ecology of speciation. Recent taxon-specific studies obtained different results regarding the role of climate in speciation in tropical versus temperate areas. Here, we quantify overlap in the climatic distributions of 93 pairs of sister species of mammals, birds, amphibians and reptiles restricted to either the New World tropics or to the Northern temperate zone. We show that elevational ranges of tropical- and temperate-zone species do not differ from one another, yet the temperature range experienced by species in the temperate zone is greater than for those in the tropics. Moreover, tropical sister species tend to exhibit greater similarity in their climatic distributions than temperate sister species. This pattern suggests that evolutionary conservatism in the thermal niches of tropical taxa, coupled with the greater thermal zonation of tropical mountains, may result in increased opportunities for allopatric isolation, speciation and the accumulation of species in tropical montane regions. Our study exemplifies the power of combining phylogenetic and spatial datasets of global climatic variation to explore evolutionary (rather than purely ecological) explanations for the high biodiversity of tropical montane regions.     

The forest batis, Batis mixta, is two species: description of a new, narrowly distributed Batis species in the Eastern Arc biodiversity hotspot

The forest batis, Batis mixta, is a common bird of the forests of the Eastern Arc Mountains of Tanzania and in some adjacent montane and coastal forests. Through new collecting efforts in most of this range we documented a well-marked change in morphology in the middle of the range. Supplementary genetic studies of the historical population structure suggest connectivity among the south-western and northern/coastal populations, but not between these parapatric groups. It is concluded that two species are involved, and a new name B. crypta is proposed for the south-western populations. A marked genetic break also exists towards B. capensis sola in northern Malawi. The morphologically distinctive form reichenowi in south-eastern Tanzania is genetically nested within B. mixta, and for now we keep it as a subspecies of B. mixta.     

Phylogenetics, biogeography and classification of, and character evolution in, gamebirds (Aves: Galliformes): effects of character exclusion, data partitioning and missing data

The phylogenetic relationships, biogeography and classification of, and morpho‐behavioral (M/B) evolution in, gamebirds (Aves: Galliformes) are investigated. In‐group taxa (rooted on representatives of the Anseriformes) include 158 species representing all suprageneric galliform taxa and 65 genera. The characters include 102 M/B attributes and 4452 nucleic acid base pairs from mitochondrial cytochrome b (CYT B), NADH dehydrogenase subunit 2 (ND2), 12S ribosomal DNA (12S) and control region (CR), and nuclear ovomucoid intron G (OVO‐G). Analysis of the combined character data set yielded a single, completely resolved cladogram that had the highest levels of jackknife support, which suggests a need for a revised classification for the phasianine galliforms. Adding 102 M/B characters to the combined CYT B and ND2 partitions (2184 characters) decisively overturns the topology suggested by analysis of the two mtDNA partitions alone, refuting the view that M/B characters should be excluded from phylogenetic analyses because of their relatively small number and putative character state ambiguity. Exclusion of the OVO‐G partition (with > 70% missing data) from the combined data set had no effect on cladistic structure, but slightly lowered jackknife support at several nodes. Exclusion of third positions of codons in an analysis of a CYT B + ND2 partition resulted in a massive loss of resolution and support, and even failed to recover the monophyly of the Galliformes with jackknife support. A combined analysis of putatively less informative, “non‐coding” characters (CYT B/ND2 third position sites + CR +12S + OVO‐G sequences) yielded a highly resolved consensus cladogram congruent with the combined‐evidence cladogram. Traditionally recognized suprageneric galliform taxa emerging in the combined cladogram are: the families Megapodiidae (megapodes), Cracidae (cracids), Numididae (guineafowls), Odontophoridae (New World quails) and Phasianidae (pheasants, pavonines, partridges, quails, francolins, spurfowls and grouse) and the subfamilies Cracinae (curassows, chachalacas and the horned guan), Penelopinae (remaining guans), Pavoninae sensu lato (peafowls, peacock pheasants and argus pheasants), Tetraoninae (grouse) and Phasianinae (pheasants minus Gallus). The monophyly of some traditional groupings (e.g., the perdicinae: partridges/quails/francolins) is rejected decisively, contrasted by the emergence of other unexpected groupings. The most remarkable phylogenetic results are the placement of endemic African galliforms as sisters to geographically far‐distant taxa in Asia and the Americas. Biogeographically, the combined‐data cladogram supports the hypothesis that basal lineages of galliforms diverged prior to the Cretaceous/Tertiary (K‐T) Event and that the subsequent cladogenesis was influenced by the break‐up of Gondwana. The evolution of gamebirds in Africa, Asia and the Americas has a far more complicated historical biogeography than suggested to date. With regard to character evolution: spurs appear to have evolved at least twice within the Galliformes; a relatively large number of tail feathers (≥ 14) at least three times; polygyny at least twice; and sexual dimorphism many times. © The Willi Hennig Society 2006.     

Phylogeny and biogeography of the genus Illadopsis (Passeriformes: Timaliidae) reveal the complexity of diversification of some African taxa

African jungle babblers or illadopsises, genus Illadopsis Heine, 1859, are small shy babblers which occupy the undergrowth of African humid forest habitats. The taxonomy of Illadopsis as well as its biogeography are currently poorly known because the morphological differentiation is rather subtle and no phylogenetic analysis has been undertaken. To investigate these issues, we sequenced four loci (mitochondrial ND2 and ND3, and nuclear myoglobin intron 2 and β-fibrinogen intron 5) for the seven species of Illadopsis . Our analyses retrieve the monophyly of Illadopsis and suggest that I. albipectus and I. cleaveri , I. puveli and I. rufescens , some individuals of I. rufipennis and I. pyrrhoptera are sister taxa respectively. I. fulvescens appears to be an isolated taxon and our data reveal several cases of "incipient speciation" among its populations. Our dating analyses, using a Bayesian relaxed-clock method, reveal that most splits in Illadopsis occurred synchronously around the Plio-Pleistocene transition, suggesting that some diversification events in African forest taxa took place before the onset of the large-amplitude climatic cycles of the Pleistocene epoch. Thus, the diversification of African taxa in time and space to be more complex than the Pleistocene time frame traditionally associated with the diversification of African forest taxa. Instead we observe a process of differentiation which roughly corresponds to the broadly hypothesised lowland refugia of upper Guinea, eastern and western Guinea-Congolia, although the time frame of this divergence well predates the Pleistocene epoch. Our results also suggest that deep genetic divergences do exist among species complexes of African birds which differ only slightly in morphological characters. As such, molecular analyses are powerful and essential tools if we are to construct the evolutionary history of such lineages in a meaningful manner.     

Development and characterization of microsatellite loci from the Great White Pelican (Pelecanus onocrotalus) and widespread application to other members of the Pelecanidae

We describe the isolation of 10 microsatellite loci from the Great White Pelican using an enrichment protocol. All loci were variable with the number of alleles ranging from 2 to 19, and observed heterozygosity ranging from 0.261 to 0.913. Two loci were out of Hardy–Weinberg equilibrium, although in each case this was restricted to one of the two populations screened. None of the loci were linked. Eight to 10 loci PCR-amplified in three related species: Brown, American White and Pink-backed Pelicans. These loci should prove to be widely applicable to studies of phylogeography and demography in pelicans globally.     

A role for zinc in postsynaptic density asSAMbly and plasticity?

Chemical synapses are asymmetric cell junctions that mediate communication between neurons. Multidomain scaffolding proteins of the Shank family act as major organizing elements of the "postsynaptic density"--that is, the cytoskeletal protein matrix associated with the postsynaptic membrane. A recent study has shown that the C-terminal sterile alpha-motif or "SAM domain" of Shank3 (also known as ProSAP2) can form two-dimensional sheets of helical fibers. Assembly and packaging of these fibers are markedly enhanced by the presence of Zn2+ ions. Zn2+ can be released together with glutamate from synaptic vesicles and can enter the postsynaptic cell through specific ionotropic receptors. Based on these observations, we propose a new model of synaptic plasticity in which Zn2+ influx directly and instantly modulates the structure and function of the postsynaptic density.     

Administration and interpretation of the Trail Making Test

Measurement of cognitive functions is an increasingly important goal for clinicians and researchers. Many neuropsychological test batteries are comprehensive and require specialized training to administer and interpret. The Trail Making Test is an accessible neuropsychological instrument that provides the examiner with information on a wide range of cognitive skills and can be completed in 5-10 min. Its background, psychometric properties, administration procedures and interpretive guidelines are provided in this protocol.     

The African warbler genus Hyliota as a lost lineage in the Oscine songbird tree: molecular support for an African origin of the Passerida

The African genus Hyliota includes three or four species of warbler-like birds of uncertain phylogenetic affinities, as it has historically been placed in different avian families that are now known to represent unrelated lineages: Malaconotidae (bush-shrikes), Platysteiridae (batises and wattle-eyes), Muscicapidae (Old World flycatchers) and Sylviidae (Old-World Warblers). To assess the affinities of Hyliota we sequenced a mitochondrial protein-coding gene (ND2, 1018bp) and a nuclear intron (myoglobin intron-2, 685bp). Our analyses suggest that all previous hypotheses concerning the affinities of Hyliota are erroneous. Instead, Hyliota represents a basal branch in the Passerida radiation with no close relatives. Our results, which also include analyses of relationships among other of other atypical songbird genera, lend support to an African origin of the Passerida songbird radiation.