Search results for "Holarctic"

Microevolution of eastern palaearctic Grey tits as indicated by their vocalizations (Parus [Poecile]: Paridae, Aves) I. Parus montanus: Contributions…

2009

Within the Palaearctic Region, the Willow tit (Parus montanus) displays four vicariant forms of territorial song. 1. “Alpine” form (pure single-frequency whistles, Fig. 5: 1) in the Alps and adjacent mountains to the East. 2. “Lowland” or “Normal” form (frequency change from high to low within one note, Fig. 5: 2) in the other parts of NW, Central and SE Europe. 3. In populations of N and E Europe as well as of W and E Siberia every individual bird uses - so far as known - both song types; this “Siberian” form (Figs. 1, 2) includes intergrades (Fig. 3). The comparatively type-rich Siberian repertoire is found in a vast area from N and E Europe to the Amur River and Ussuriland in Siberia. 4.…

Experimental Infection of Voles with Francisella tularensis Indicates Their Amplification Role in Tularemia Outbreaks

2014

Tularemia outbreaks in humans have been linked to fluctuations in rodent population density, but the mode of bacterial maintenance in nature is unclear. Here we report on an experiment to investigate the pathogenesis of Francisella tularensis infection in wild rodents, and thereby assess their potential to spread the bacterium. We infected 20 field voles (Microtus agrestis) and 12 bank voles (Myodes glareolus) with a strain of F. tularensis ssp. holarctica isolated from a human patient. Upon euthanasia or death, voles were necropsied and specimens collected for histological assessment and identification of bacteria by immunohistology and PCR. Bacterial excretion and a rapid lethal clinical …

Geographic variation in the warning signals of the wood tiger moth (Parasemia plantaginis; Arctiidae)

2013

A Revision of theniveaGroup of the Shore-Fly GenusDitrichophoraCresson (Diptera: Ephydridae)

2010

ABSTRACT Species of the nivea group (genus Ditrichophora Cresson) are revised. The group now includes four species of which one, D. gulkana (Alaska and Mongolia), is newly described. The group is now known to have a Holarctic distribution with two species, D. gulkana and D. nivea, being the first reported from the Nearctic Region. Another Asian species, D. brunnicosa, previously placed in Diclasiopa, is transferred to this group (genus Ditrichophora) and is also reported from Mongolia. To facilitate identification of these rare species, we have included diagnoses of the tribe, genus, and species group and have also provided an annotated key to Holarctic genera of the tribe Discocerinini and…

Die Ölblumensymbiosen - Parallelismus and andere Aspekte ihrer Entwicklung in Raum and Zeit1, 2

2009

The oil-bee/oil-flower relationships: parallelism and other aspects of their evolution in space and time A survey is given of our present knowledge and existing hypotheses concerning the biogeography, history, and phylogeny of plant taxa yielding fatty oil as a floral reward, and of the bee genera involved in their pollination. Four syngenetic complexes of the symbiosis arose convergently: The neotropical, the paleotropical, the holarctic, and the capensic complex. On the basis of the mutual structural adaptations of bees and flowers it is concluded that, in addition, parallelism within related groups as a result of a common tendency to develop the respective organs, has played an important…

Revision of New World Species of the Shore-fly Subgenus Allotrichoma Becker of the Genus Allotrichoma with Description of the Subgenus Neotrichoma (D…

2012

The New World species of the subgenera Allotrichoma Becker and Neotrichoma (new subgenus) are revised, including a phylogenetic analysis of the species groups and subgenera within the genus Allotrichoma. For phylogenetic perspective and to document the monophyly of the genus Allotrichoma and its included subgenera and species groups, we also provide a cladistic analysis of genera within the tribe Hecamedini. The ingroup included seven exemplar congeners from within Allotrichoma. Outgroup sampling included exemplars of other genera within Hecamedini and from the putative sister group, Lipochaetini, and to root the analysis, we used an exemplar of the tribe Discocerinini. Analyses with succes…