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Monday, 7 April 2014

Bird Research this week on PubMed: April 2014 Week 1

PubMed listing for 'bird' OR 'songbird' excluding references to influenza and flu - April 2014 Week 1           


1. PLoS One. 2014 Apr 2;9(4):e90583. doi: 10.1371/journal.pone.0090583. eCollection 2014.

Individual Winter Movement Strategies in Two Species of Murre (Uria spp.) in the Northwest Atlantic.

McFarlane Tranquilla LA1, Montevecchi WA1, Fifield DA1, Hedd A1, Gaston AJ2, Robertson GJ3, Phillips RA4.Author information:
1Cognitive and Behavioural Ecology, Department of Psychology, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada.
2Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, Ontario, Canada.
3Wildlife Research Division, Environment Canada, Mount Pearl, Newfoundland and Labrador, Canada.
4British Antarctic Survey, Natural Environment Research Council, Cambridge, United Kingdom.

Abstract

Individual wintering strategies and patterns of winter site fidelity in successive years are highly variable among seabird species. Yet, an understanding of consistency in timing of movements and the degree of site fidelity is essential for assessing how seabird populations might be influenced by, and respond to, changing conditions on wintering grounds. To explore annual variation in migratory movements and wintering areas, we applied bird-borne geolocators on Thick-billed Murres (Uria lomvia, n = 19) and Common Murres (U. aalge, n = 20) from 5 colonies in the Northwest Atlantic for 2-4 consecutive years. Thick-billed Murres ranged widely and among-individual wintering strategies were highly variable, whereas most Common Murres wintered relatively near their colonies, with among-individual variation represented more by the relative use of inshore vs. offshore habitat. Within individuals, some aspects of the wintering strategy were more repeatable than others: colony arrival and departure dates were more consistent by individual Common than Thick-billed Murres, while the sizes of home ranges (95% utilization distributions) and distances travelled to wintering area were more repeatable for both species. In consecutive years, individual home ranges overlapped from 0-64% (Thick-billed Murres) and 0-95% (Common Murres); and the winter centroids were just 239 km and 169 km apart (respectively). Over the 3-4 year timescale of our study, individuals employed either fixed or flexible wintering strategies; although most birds showed high winter site fidelity, some shifted core ranges after 2 or 3 years. The capacity among seabird species for a combination of fidelity and flexibility, in which individuals may choose from a range of alternative strategies, deserves further, longer term attention.
Free Article
PMID: 24694734 [PubMed - in process]
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2. Nat Commun. 2014 Apr 2;5:3567. doi: 10.1038/ncomms4567.

Competition and constraint drove Cope's rule in the evolution of giant flying reptiles.

Benson RB1, Frigot RA2, Goswami A3, Andres B4, Butler RJ5.Author information:
1Department of Earth Sciences, University of Oxford, Oxford OX1 3AN, UK.
2Center for Functional Anatomy and Evolution, Johns Hopkins University, Baltimore, Maryland 21205, USA.
3Department of Genetics, Evolution & Environment and Department of Earth Sciences, University College London, London WC1E 6BT, UK.
4School of Geosciences, University of South Florida, Tampa, Florida 33620, USA.
5School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK.

Abstract

The pterosaurs, Mesozoic flying reptiles, attained wingspans of more than 10 m that greatly exceed the largest birds and challenge our understanding of size limits in flying animals. Pterosaurs have been used to illustrate Cope's rule, the influential generalization that evolutionary lineages trend to increasingly large body sizes. However, unambiguous examples of Cope's rule operating on extended timescales in large clades remain elusive, and the phylogenetic pattern and possible drivers of pterosaur gigantism are uncertain. Here we show 70 million years of highly constrained early evolution, followed by almost 80 million years of sustained, multi-lineage body size increases in pterosaurs. These results are supported by maximum-likelihood modelling of a comprehensive new pterosaur data set. The transition between these macroevolutionary regimes is coincident with the Early Cretaceous adaptive radiation of birds, supporting controversial hypotheses of bird-pterosaur competition, and suggesting that evolutionary competition can act as a macroevolutionary driver on extended geological timescales.
PMID: 24694584 [PubMed - in process]
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3. Virus Genes. 2014 Apr 2. [Epub ahead of print]

Evolutionary dynamics of West Nile virus in Georgia, 2001-2011.

Phillips JE1, Stallknecht DE, Perkins TA, McClure NS, Mead DG.Author information:
1Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, 589 D.W. Brooks Drive, Athens, GA, 30602, USA, jamiep44@gmail.com.

Abstract

From 1999-2001, West Nile virus (WNV) spread throughout the eastern United States (US) and was first detected in Georgia in 2001. To date, the virus has been detected in over 2,500 dead wild bird and mosquito samples from across Georgia. We sequenced the premembrane (preM) and envelope gene (E) (2004 bp) from 111 isolates collected from 2001 to 2011. To assess viral gene flow from other geographic regions in the US, we combined our data with WNV sequences available at the National Center for Biotechnology Information (NCBI) and performed phylogenetic analysis. We found evidence that WNV isolates detected in Chatham County Georgia most likely originated from the Northeastern United States. These results highlight the growing importance of adequate genetic surveillance for monitoring and controlling viruses of public health concern.
PMID: 24691819 [PubMed - as supplied by publisher]
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4. Photochem Photobiol. 2014 Apr 1. doi: 10.1111/php.12276. [Epub ahead of print]

Observation of Magnetic Field Effects on Transient Fluorescence Spectra of Cryptochrome 1 from Homing Pigeons.

Du XL1, Wang J, Pan WS, Liu QJ, Wang XJ, Wu WJ.Author information:
1Department of Chemistry and Biology, National University of Defense Technology, Changsha, Hunan, 410000, China.

Abstract

Cryptochromes are suggested to be involved in the bird magnetoreception based on the radical pair mechanism (RPM), a well established theory of weak magnetic field effects on chemical reactions. Two members of cryptochrome/photolyase family were found to response to magnetic field, however, no direct responses of bird cryptochrome to magnetic field as weak as the Earth's magnetic field has been obtained so far. In the present study, we used transient fluorescence spectroscopy to characterize the weak magnetic field effects of bird cryptochromes. To do this, we cloned the cryptochrome 1 gene (clCRY1) from the retina of homing pigeons (Columba livia), expressed it in insect Sf9 cells and analyzed the transient fluorescence of purified clCRY1 by application of 45-300 μT magnetic fields. The flavin adenine dinucleotide (FADox ) and glucose oxidase (GOD) in PBS buffer were set as controls which could be excited by light to generate radicals but would not be sensitive to magnetic field. We observed that the transient fluorescence spectra of clCRY1 were sensitive to the applied magnetic field at room temperature. Our result provides a new proof of the cryptochrome-based model of avian magnetoreception in vitro. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
PMID: 24689535 [PubMed - as supplied by publisher]
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5. Evolution. 2014 Apr 1. doi: 10.1111/evo.12417. [Epub ahead of print]

RECONSTRUCTING THE EVOLUTION OF SEXUAL DICHROMATISM: CURRENT COLOR DIVERSITY DOES NOT REFLECT PAST RATES OF MALE AND FEMALE CHANGE.

Price JJ1, Eaton MD.Author information:
1Department of Biology, St. Mary's College of Maryland, St. Mary's City, MD, 20686, USA. jjprice@smcm.edu.

Abstract

Males of sexually dimorphic species often appear more divergent among taxa than do females, so it is often assumed that evolutionary changes have occurred primarily in males. Yet, sexual dimorphisms can result from historical changes in either or both of the sexes, and few previous studies have investigated such patterns using phylogenetic methods. Here we describe the evolution of male and female plumage colors in the grackles and allies (Icteridae), a songbird clade with a broad range in levels of sexual dichromatism. Using a model of avian perceptual color space, we calculated color distances within and among taxa on a molecular phylogeny. Our results show that female plumage colors have changed more dramatically than male colors in the evolutionary past, yet male colors are significantly more divergent among species today. Historical increases in dichromatism have involved changes in both sexes, whereas decreases in dichromatism have nearly always involved females evolving rapidly to look like males. Dichromatism is also associated with mating system in this group, with monogamous taxa tending to exhibit relatively low levels of sexual dichromatism. Our findings suggest that, despite appearances, female plumage evolution plays a more prominent role in sexual dichromatism than is generally assumed. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
PMID: 24689951 [PubMed - as supplied by publisher]
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