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Fecundity selection does not vary along a large geographical cline of trait means in a passerine bird
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![点击此处可从《Biological journal of the Linnean Society. Linnean Society of London》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Päivi M. Sirkiä Peter Adamík Alexandr V. Artemyev Eugen Belskii Christiaan Both Stanislav Bureš Malcolm Burgess Andrey V. Bushuev Jukka T. Forsman Vladimir Grinkov Dieter Hoffmann Antero Järvinen Miroslav Král Indrikis Krams Helene M. Lampe Juan Moreno Marko Mägi Andreas Nord Jaime Potti Pierre‐Alain Ravussin Leonid Sokolov Toni Laaksonen 《Biological journal of the Linnean Society. Linnean Society of London》2015,114(4):808-827
Local environmental and ecological conditions are commonly expected to result in local adaptation, although there are few examples of variation in phenotypic selection across continent‐wide spatial scales. We collected standardized data on selection with respect to the highly variable plumage coloration of pied flycatcher (Ficedula hypoleuca Pall.) males from 17 populations across the species' breeding range. The observed selection on multiple male coloration traits via the annual number of fledged young was generally relatively weak. The main aim of the present study, however, was to examine whether the current directional selection estimates are associated with distance to the sympatric area with the collared flycatcher (Ficedula albicollis Temminck), a sister species with which the pied flycatcher is showing character displacement. This pattern was expected because plumage traits in male pied flycatchers are changing with the distance to these areas of sympatry. However, we did not find such a pattern in current selection on coloration. There were no associations between current directional selection on ornamentation and latitude or longitude either. Interestingly, current selection on coloration traits was not associated with the observed mean plumage traits of the populations. Thus, there do not appear to be geographical gradients in current directional fecundity selection on male plumage ornamentation. The results of the present study do not support the idea that constant patterns in directional fecundity selection would play a major role in the maintenance of coloration among populations in this species. By contrast, the tendency for relatively weak mosaic‐like variation in selection among populations could reflect just a snapshot of temporally variable, potentially environment‐dependent, selection, as suggested by other studies in this system. Such fine‐grained variable selection coupled with gene flow could maintain extensive phenotypic variation across populations. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 808–827. 相似文献
76.
Sympatric divergence and clinal variation in multiple coloration traits of Ficedula flycatchers
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![点击此处可从《Journal of evolutionary biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
T. Laaksonen P. M. Sirkiä S. Calhim J. E. Brommer P. K. Leskinen C. R. Primmer P. Adamík A. V. Artemyev E. Belskii C. Both S. Bureš M. D. Burgess B. Doligez J. T. Forsman V. Grinkov U. Hoffmann E. Ivankina M. Král I. Krams H. M. Lampe J. Moreno M. Mägi A. Nord J. Potti P.‐A. Ravussin L. Sokolov 《Journal of evolutionary biology》2015,28(4):779-790
Geographic variation in phenotypes plays a key role in fundamental evolutionary processes such as local adaptation, population differentiation and speciation, but the selective forces behind it are rarely known. We found support for the hypothesis that geographic variation in plumage traits of the pied flycatcher Ficedula hypoleuca is explained by character displacement with the collared flycatcher Ficedula albicollis in the contact zone. The plumage traits of the pied flycatcher differed strongly from the more conspicuous collared flycatcher in a sympatric area but increased in conspicuousness with increasing distance to there. Phenotypic differentiation (PST) was higher than that in neutral genetic markers (FST), and the effect of geographic distance remained when statistically controlling for neutral genetic differentiation. This suggests that a cline created by character displacement and gene flow explains phenotypic variation across the distribution of this species. The different plumage traits of the pied flycatcher are strongly to moderately correlated, indicating that they evolve non‐independently from each other. The flycatchers provide an example of plumage patterns diverging in two species that differ in several aspects of appearance. The divergence in sympatry and convergence in allopatry in these birds provide a possibility to study the evolutionary mechanisms behind the highly divergent avian plumage patterns. 相似文献
77.
L. M. Vasilyak A. I. Vasiliev S. V. Kostyuchenko D. V. Sokolov A. Yu. Startsev N. N. Kudryavtsev 《Plasma Physics Reports》2011,37(13):1173-1177
For the first time, cathode and anode drops of powerful low-pressure amalgam lamps were measured. The lamp discharge current
is 3.2 A, discharge current frequency is 43 kHz, linear electric power is 2.4 W/cm. The method of determination of a cathode
drop is based on the change of a lamp operating voltage at variation of the electrode filament current at constant discharge
current. The total (cathode plus anode) drop of voltage was measured by other, independent ways. The maximum cathode fall
is 10.8 V; the anode fall corresponding to the maximal cathode fall is 2.4 V. It is shown that in powerful low pressure amalgam
lamps the anode fall makes a considerable contribution (in certain cases, the basic one) to heating of electrodes. Therefore,
the anode fall cannot be neglected, at design an electrode and ballast of amalgam lamps with operating discharge current frequency
of tens of kHz. 相似文献
78.
V V Sokolov O A Kaplunova Ia A Khananashvili A V Markevich E V Kharlamov 《Arkhiv anatomii, gistologii i émbriologii》1989,97(12):40-45
Architectonics of intraorganic arterial vessels in the cervical cortex, heart, kidneys and spleen have been investigated in 40 normotensive and spontaneously hypertensive rats, 6 months and 1 year old. In all the organs studied a direct dependence has been revealed between the degree of changes in the intraorganic arteries and relative content of the arterial vessels in the tissue organs. Functional changes of the arterial vessels in the organs studied observed during the hypertensive phase, transfer into the organic ones, as a result of prolonged adaptation, when the stage of a stable hypertension takes place. 相似文献
79.
Filonov AE Akhmetov LI Puntus IF Esikova TZ Gafarov AB Izmalkova TIu Sokolov SL Kosheleva IA Boronin AM 《Mikrobiologiia》2005,74(4):526-532
A genetically marked, plasmid-containing, naphthalene-degrading strain, Pseudomonas putida KT2442(pNF142::TnMod-OTc), has been constructed. The presence of the gfp gene (which codes for green fluorescent protein) and the kanamycin and rifampicin resistance genes in the chromosome of this strain allows the strain's fate in model soil systems to be monitored, whereas a minitransposon, built in naphthalene biodegradation plasmid pNF142, contains the tetracycline resistance gene and makes it possible to follow the horizontal transfer of this plasmid between various bacteria. Plasmid pNF142::TnMod-OTc is stable in strain P. putida KT2442 under nonselective conditions. The maximal specific growth rate of this strain on naphthalene was found to be higher than that of the natural host of plasmid pNF142. When introduced into a model soil system, the genetically marked strain is stable and competitive for 40 days. The transfer of marked plasmid pNF142::TnMod-OTc to natural soil bacteria, predominantly fluorescent pseudomonads, has been detected. 相似文献
80.
The study of parasites associated with the anadromous mikizha from several rivers of the Western Kamchatka has revealed 44 parasite species. The majority of parasites (59%) belong to marine and estuarine-marine species. Lecithophyllum bothryophorum, Echinorhynchus leidyi and plerocercoids of the family Litobothriidae were found for the first time in anadromous fish entering into Asian continental watersheds. It has been revealed that only a few specimens of the anadromous mikizha feed in fresh waters. Most of feeding fish consume a minor amount of food, and this feeding is occasional. Young forms of intestinal parasites of the freshwater and estuarine-freshwater groups (Neoechinorhynchus spp., Crepidostomum spp., Cucullanus truttae, Eubothrium salvelinf) come into anadromous fishes mainly before their entering in fresh waters. 相似文献