Universal Trap Timer Design to Examine Temporal Activity of Wildlife

Abstract: We designed a reliable and inexpensive universal trap timer that records the time from the moment a single-live-capture trap is triggered by an animal to when the observer checks the trap. Combined with trapping information, the diel activity pattern of a given species or demographic group can then be described or compared between imposed treatments. The universal trap timer is adaptable to operate reliably with most single-capture trap designs, requires no permanent modification of traps, and is easy to construct.     

A new arthropod from the Early Cambrian of North Greenland,with a ‘great appendage’‐like antennula

Kiisortoqia soperi gen. et sp. nov. is an arthropod species from the Early Cambrian Sirius Passet Lagerstätte of North Greenland. A head, incorporating four appendiferous segments and biramous limbs, with an anteroposteriorly compressed basipod with a spine bearing median edge, support the euarthropod affinities of K. soperi gen. et sp. nov. Similarities with ‘short great appendage’ arthropods, or megacheirans, like the nine‐segmented endopod, and the flap‐ or paddle‐like exopod, may be symplesiomorphies. The antennula, however, resembles in composition and size the anteroventral raptorial appendage of anomalocaridids. Thus, the morphology of K. soperi gen. et sp. nov. provides additional support for the homologization of the anomalocaridid ‘great appendage’ with the appendage of the antennular or deutocerebral segment of extant Euarthropoda. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 477–500.     

Revision of the genus Acrochordiceras Hyatt, 1877 (Ammonoidea,Middle Triassic): morphology,biometry, biostratigraphy and intra‐specific variability

Abstract: The family Acrochordiceratidae Arthaber, 1911 ranges in age from latest Spathian to the middle/late Anisian boundary, and it represents a major component of ammonoid faunas during that time. The middle Anisian genus Acrochordiceras Hyatt, 1877 is the most widespread taxon of the family and occurs abundantly worldwide within the low paleolatitude belt. However, there is a profusion of species names available for Acrochordiceras. This excessive diversity at the species level essentially results from the fact that sufficiently large samples were not available, thus leading to a typological approach to its taxonomy. Based on new extensive collections obtained from the Anisian (Middle Triassic) Fossil Hill Member (Star Peak Group, north‐west Nevada) for which a high resolution biostratigraphic frame is available, the taxonomy and biostratigraphy of the genus Acrochordiceras Hyatt, 1877 is herein revised with respect to its intra‐specific variation. Morphological and biometric studies (c. 550 bedrock‐controlled specimens were measured) show that only one species occurs in each stratigraphic level. Continuous ranges of intra‐specific variation of studied specimens enable us to synonymize Haydenites Diener, 1907, Silesiacrochordiceras Diener, 1916 and Epacrochordiceras Spath, 1934 with Acrochordiceras Hyatt, 1877. Three stratigraphically successive species are herein recognized in the low paleolatitude middle Anisian faunas from Nevada: A. hatschekii (Diener, 1907), A. hyatti Meek, 1877 and A. carolinae Mojsisovics, 1882. Moreover, an assessment of intra‐specific variation of the adult size range does not support recognition of a dimorphic pair (Acrochordiceras and Epacrochordiceras) as previously suggested by other workers (Epacrochordiceras is the compressed and weakly ornamented end‐member variant of Acrochordiceras). The successive middle Anisian species of Acrochordiceras form an anagenetic lineage characterized by increasing involution, adult size and intra‐specific variation. This taxonomic revision based on new bedrock‐controlled collections is thus an important prerequisite before studying the evolution of the group.     

Heritability of anti‐predatory traits: vigilance and locomotor performance in marmots

Animals must allocate some proportion of their time to detecting predators. In birds and mammals, such anti‐predator vigilance has been well studied, and we know that it may be influenced by a variety of intrinsic and extrinsic factors. Despite hundreds of studies focusing on vigilance and suggestions that there are individual differences in vigilance, there have been no prior studies examining its heritability in the field. Here, we present one of the first reports of (additive) genetic variation in vigilance. Using a restricted maximum likelihood procedure, we found that, in yellow‐bellied marmots (Marmota flaviventris), the heritability of locomotor ability (h² = 0.21), and especially vigilance (h² = 0.08), is low. These modest heritability estimates suggest great environmental variation or a history of directional selection eliminating genetic variation in these traits. We also found a significant phenotypic (r_P = ?0.09 ± 0.04, P = 0.024) and a substantial, but not significant, genetic correlation (r_A = ?0.57 ± 0.28, P = 0.082) between the two traits (slower animals are less vigilant while foraging). We found no evidence of differential survival or longevity associated with particular phenotypes of either trait. The genetic correlation may persist because of environmental heterogeneity and genotype‐by‐environment interactions maintaining the correlation, or because there are two ways to solve the problem of foraging in exposed areas: be very vigilant and rely on early detection coupled with speed to escape, or reduce vigilance to minimize time spent in an exposed location. Both strategies seem to be equally successful, and this ‘locomotor ability‐wariness’ syndrome may therefore allow slow animals to compensate behaviourally for their impaired locomotor ability.     

Phylogenetic relationships within Maldanidae (Capitellida,Annelida), based on morphological characters

The Maldanidae annelid worms are reviewed and the phylogenetic relationships of their subgroups provided, based on Hennigian principles and maximum parsimony. Characters were coded as binary and multistate (transformation series). We used 33 terminal taxa (species), and 50 characters. Characters were treated as unordered and of equal weight, and analysis was run in TNT. Three equally most-parsimonious trees were obtained with heuristic searches, with lengths of 64 steps; CI = 0.95, and RI = 0.98. The monophyly of Maldanidae was supported with 100% of bootstrap and jackknife values. As a result of our analysis, Arenicolidae remains the sister-group of Maldanidae, and both should be referred to Maldanomorpha. Maldanidae was supported by the following synapomorphies: dorsal prostomium; prostomium keel-shaped and fused to peristomium; torus globose behind median chaetigers; median chaetigers greatly elongated; number of pre-anal segments reduced. The subfamily Bogueinae was not monophyletic; Boguea and Boguella were included within Rhodininae. Clymenura, previously included in the Clymenurinae, was included within Euclymeninae. The taxa Notoproctinae, Maldaninae, Nicomachinae and Euclymeninae were grouped in the Maldanoplaca, a new taxon. Eight further new clades have been found, but were not named.     

A multiplex set of microsatellite markers for the scarlet rosefinch (Carpodacus erythrinus)

Cardueline finches have become important models in studies of sexual selection and evolution of carotenoid‐based ornamentation. Here, we describe eight new polymorphic microsatellites isolated from the Scarlet rosefinch (Carpodacus erythrinus) and four from the House finch (Carpodacus mexicanus). Together with the cross‐species amplification of additional loci, originally published for two species of songbirds, we optimized a multiplex panel for C. erythrinus allowing genotyping of 22 polymorphic loci. Number of alleles and heterozygosity per locus in a sample of 34 individuals ranged from three to 38 and from 0.27 to 0.94, respectively.     

The relationship between introduced European Starlings and the reproductive activities of Mountain Bluebirds and Tree Swallows in British Columbia,Canada

The European Starling Sturnus vulgaris is an introduced species in North America and is an aggressive competitor for tree cavity nest‐sites. Starlings are commonly considered to influence nest‐site selection and reproductive success of native cavity‐nesting species negatively. We examined the relationship between Starling nest density and the fecundity of two native secondary cavity‐using passerines, Mountain Bluebird Sialia currucoides and Tree Swallow Tachycineta bicolor. We monitored a total of 622 nests (approximately equal numbers for each of the three species) in woodpecker‐excavated and naturally occurring cavities in 29 small forest groves in central British Columbia, Canada, between 2000 and 2009. The dimensions of cavities used and the timing of nest initiation overlapped for all species, although Starlings initiated clutches earliest. Mixed‐effects models were used to assess whether nest abundance, clutch size or nest success were affected directly by Starling nest abundance, or indirectly via a shift in cavity selection or timing of breeding. Starlings and Mountain Bluebirds showed inverse trends in nest abundance. Mountain Bluebird clutch sizes were smaller if they were initiated later in the breeding season. There was weak evidence that Tree Swallow clutch size decreased with cavity depth when Starling nests were abundant, and increased with cavity depth where there were few Starling nests. We conclude that despite the aggressive nature of this exotic cavity‐nester, the influence of Starlings on native secondary cavity‐nesting passerines is modest where cavities are abundant.     

A spatially explicit analysis to extrapolate carbon fluxes in upland tundra where permafrost is thawing

One of the most important changes in high‐latitude ecosystems in response to climatic warming may be the thawing of permafrost soil. In upland tundra, the thawing of ice‐rich permafrost can create localized surface subsidence called thermokarst, which may change the soil environment and influence ecosystem carbon release and uptake. We established an intermediate scale (a scale in between point chamber measurements and eddy covariance footprint) ecosystem carbon flux study in Alaskan tundra where permafrost thaw and thermokarst development had been occurring for several decades. The main goal of our study was to examine how dynamic ecosystem carbon fluxes [gross primary production (GPP), ecosystem respiration (R_eco), and net ecosystem exchange (NEE)] relate to ecosystem variables that incorporate the structural and edaphic changes that co‐occur with permafrost thaw and thermokarst development. We then examined how these measured ecosystem carbon fluxes responded to upscaling. For both spatially extensive measurements made intermittently during the peak growing season and intensive measurements made over the entire growing season, ecosystem variables including degree of surface subsidence, thaw depth, and aboveground biomass were selected in a mixed model selection procedure as the ‘best’ predictors of GPP, R_eco, and NEE. Variables left out of the model (often as a result of autocorrelation) included soil temperature, moisture, and normalized difference vegetation index. These results suggest that the structural changes (surface subsidence, thaw depth, aboveground biomass) that integrate multiple effects of permafrost thaw can be useful components of models used to estimate ecosystem carbon exchange across thermokarst affected landscapes.     

Symbiotic streptomycetes in antennal glands of the South American digger wasp genus Trachypus (Hymenoptera,Crabronidae)

Several insect taxa have evolved symbioses with actinobacteria that protect the host or its nutritional resources against pathogens. Digger wasps of the genus Philanthus (‘beewolves’; Hymenoptera, Crabronidae) cultivate ‘Candidatus Streptomyces philanthi’ (Ca. S. philanthi) in specialized antennal glands and transfer them to subterranean brood cells, where the symbionts provide protection for the beewolf larva against pathogens by producing a cocktail of antibiotic substances. The present study investigates the occurrence of antennal symbionts in two species of the genus Trachypus, which is the closest relative to Philanthus. Cross sections of the antennae from females of both Trachypus denticollis and Trachypus boharti reveal bacteria‐containing gland reservoirs that are morphologically very similar to those found in Philanthus spp. Polymerase chain reaction‐based screens with specific primers, sequencing of the partial 16S rRNA gene, and fluorescence in situ hybridization confirm the presence of close relatives of ‘Ca. S. philanthi’ in T. denticollis and T. boharti. However, 16S rRNA sequence divergence between Trachypus spp. and Philanthus spp. symbionts is much higher for T. boharti than for T. denticollis, suggesting that horizontal transmission and/or de novo uptake of symbionts from the environment occurs occasionally. The results obtained indicate that the protective symbiosis with antennal actinobacteria is older and more widespread than previously recognized and occurs in at least two genera of digger wasps that comprise approximately 170 species.