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Monday, 21 April 2014

Bird Research this week on PubMed: April 2014 Week 2

PubMed listing for 'bird' OR 'songbird' excluding references to influenza and flu - April 2014 Week 2    

1. Environ Sci Pollut Res Int. 2014 Apr 17. [Epub ahead of print]

Contamination of organochlorine pesticides in water and sediments from a waterbird-inhabited lake, East Central China.

Hu Y1, Yuan L, Qi S, Liu H, Xing X .Author information:
1State Key Laboratory of Biogeology and Environmental Geology, Wuhan, 430074, People's Republic of China.

Abstract

Seventeen organochlorine pesticides (OCPs) were investigated in the water and sediments from a waterbird-inhabited lake (Yangchaihu Lake) to evaluate their current pollution levels and potential risks. The concentrations of total OCPs in water and sediments were 10.12-59.75 ng/l and 4.25-27.35 ng/g dry weight, respectively. Hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) were the most abundant OCPs, while HCB and cyclodiene pesticides were detected with low levels. Levels of ∑OCPs (sum of 17 OCPs) at sites highly influenced by waterbirds were significantly higher than the sites with no significant waterbird populations (one-way ANOVA, P < 0.05), suggesting that bird activities were one reason for concentration distribution of these pollutants. Compositional and source analyses of OCPs in water and sediments indicated that there might be fresh introduction of lindane and heptachlor. The partitions of most OCPs were not in equilibrium between water and sediments. The results of an ecological risk assessment showed that residue levels of DDTs in the studied area might pose adverse effects on ecosystems.
PMID: 24740407 [PubMed - as supplied by publisher]

2. PLoS One. 2014 Apr 16;9(4):e94437. doi: 10.1371/journal.pone.0094437. eCollection 2014.

Tracking Natal Dispersal in a Coastal Population of a Migratory Songbird Using Feather Stable Isotope (δ2H, δ34S) Tracers.

Haché S1, Hobson KA2, Bayne EM1, Van Wilgenburg SL2, Villard MA3.Author information:
1Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada.
2Environment Canada, Saskatoon, SK, Canada.
3Département de biologie, Université de Moncton, Moncton, NB, Canada.

Abstract

Adult birds tend to show high fidelity to their breeding territory or disperse over relatively short distances. Gene flow among avian populations is thus expected to occur primarily through natal dispersal. Although natal dispersal is a critical demographic process reflecting the area over which population dynamics take place, low recapture rates of birds breeding for the first time have limited our ability to reliably estimate dispersal rates and distances. Stable isotope approaches can elucidate origins of unmarked birds and so we generated year- and age-specific δ2H and δ34S feather isoscapes (ca. 180 000 km2) of coastal-breeding Ovenbirds (Seiurus aurocapilla) and used bivariate probability density functions to assign the likely natal areas of 35 males recruited as first-year breeders into a population located in northwestern New Brunswick, Canada. Most individuals (80-94% depending on the magnitude of an age correction factor used; i.e. 28-33 out of 35) were classified as residents (i.e. fledged within our study area) and estimated minimum dispersal distances of immigrants were between 40 and 240 km. Even when considering maximum dispersal distances, the likely origin of most first-year breeders was<200 km from our study area. Our method identified recruitment into our population from large geographic areas with relatively few samples whereas previous mark-recapture based methods have required orders of magnitude more individuals to describe dispersal at such geographic scales. Natal dispersal movements revealed here suggest the spatial scale over which many population processes are taking place and we suggest that conservation plans aiming to maintain populations of Ovenbirds and ecologically-similar species should consider management units within 100 or at most 200 km of target breeding populations.
PMID: 24740314 [PubMed - in process]




3. Nat Commun. 2014 Apr 16;5:3700. doi: 10.1038/ncomms4700.

Shared developmental programme strongly constrains beak shape diversity in songbirds.

Fritz JA1, Brancale J2, Tokita M2, Burns KJ3, Hawkins MB4, Abzhanov A4, Brenner MP5.Author information:
11] School of Engineering and Applied Sciences and Kavli Institute for Bionano Science and Technology, Harvard University, Cambridge, Massachusetts 02138, USA [2].
21] Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA [2].
3Department of Biology, San Diego State University, San Diego, California 92182, USA.
4Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
5School of Engineering and Applied Sciences and Kavli Institute for Bionano Science and Technology, Harvard University, Cambridge, Massachusetts 02138, USA.

Abstract

The striking diversity of bird beak shapes is an outcome of natural selection, yet the relative importance of the limitations imposed by the process of beak development on generating such variation is unclear. Untangling these factors requires mapping developmental mechanisms over a phylogeny far exceeding model systems studied thus far. We address this issue with a comparative morphometric analysis of beak shape in a diverse group of songbirds. Here we show that the dynamics of the proliferative growth zone must follow restrictive rules to explain the observed variation, with beak diversity constrained to a three parameter family of shapes, parameterized by length, depth and the degree of shear. We experimentally verify these predictions by analysing cell proliferation in the developing embryonic beaks of the zebra finch. Our findings indicate that beak shape variability in many songbirds is strongly constrained by shared properties of the developmental programme controlling the growth zone.
PMID: 24739280 [PubMed - in process]

4. Behav Res Methods. 2014 Apr 16. [Epub ahead of print]

The ALDB box: Automatic testing of cognitive performance in groups of aviary-housed pigeons.

Huber L1, Heise N, Zeman C, Palmers C.Author information:
1Messerli Research Institute, University of Veterinary Medicine, A-1210, Vienna, Austria, ludwig.huber@vetmeduni.ac.at.

Abstract

The combination of highly controlled experimental testing and the voluntary participation of unrestrained animals has many advantages over traditional, laboratory-based learning environments in terms of animal welfare, learning speed, and resource economy. Such automatic learning environments have recently been developed for primates (Fagot & Bonté, 2010; Fagot & Paleressompoulle, 2009;) but, so far, has not been achieved with highly mobile creatures such as birds. Here, we present a novel testing environment for pigeons. Living together in small groups in outside aviaries, they can freely choose to participate in learning experiments by entering and leaving the automatic learning box at any time. At the single-access entry, they are individualized using radio frequency identification technology and then trained or tested in a stress-free and self-terminating manner. The voluntary nature of their participation according to their individual biorhythm guarantees high motivation levels and good learning and test performance. Around-the-clock access allows for massed-trials training, which in baboons has been proven to have facilitative effects on discrimination learning. The performance of 2 pigeons confirmed the advantages of the automatic learning device for birds box. The latter is the result of a development process of several years that required us to deal with and overcome a number of technical challenges: (1) mechanically controlled access to the box, (2) identification of the birds, (3) the release of a bird and, at the same time, prevention of others from entering the box, and (4) reliable functioning of the device despite long operation times and exposure to high dust loads and low temperatures.
PMID: 24737096 [PubMed - as supplied by publisher]


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5. PLoS One. 2014 Apr 15;9(4):e94994. doi: 10.1371/journal.pone.0094994. eCollection 2014.

Outbreak of avian malaria associated to multiple species of Plasmodium in magellanic penguins undergoing rehabilitation in southern Brazil.

Vanstreels RE1, Kolesnikovas CK2, Sandri S2, Silveira P 3, Belo NO3, Ferreira Junior FC3, Epiphanio S4, Steindel M5, Braga EM3, Catão-Dias JL 1.Author information:
1Laboratório de Patologia Comparada de Animais Selvagens, Departamento de Patologia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, São Paulo, Brazil.
2Associação R3 Animal, Florianópolis, Santa Catarina, Brazil.
3Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
4Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, São Paulo, Brazil.
5Laboratório de Protozoologia, Departamento de Microbiologia e Parasitologia, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil.

Abstract

Avian malaria is a mosquito-borne disease caused by Plasmodium spp. Avian plasmodia are recognized conservation-threatening pathogens due to their potential to cause severe epizootics when introduced to bird populations with which they did not co-evolve. Penguins are considered particularly susceptible, as outbreaks in captive populations will often lead to high morbidity and rapid mortality. We used a multidisciplinary approach to investigate an outbreak of avian malaria in 28 Magellanic penguins (Spheniscus magellanicus) at a rehabilitation center during summer 2009 in Florianópolis, Brazil. Hemosporidian infections were identified by microscopic and molecular characterization in 64% (18/28) of the penguins, including Plasmodium (Haemamoeba) tejerai, Plasmodium (Huffia) elongatum, a Plasmodium (Haemamoeba) sp. lineage closely related to Plasmodium cathemerium, and a Haemoproteus (Parahaemoproteus) sp. lineage closely related to Haemoproteus syrnii. P. tejerai played a predominant role in the studied outbreak and was identified in 72% (13/18) of the hemosporidian-infected penguins, and in 89% (8/9) of the penguins that died, suggesting that this is a highly pathogenic parasite for penguins; a detailed description of tissue meronts and lesions is provided. Mixed infections were identified in three penguins, and involved P. elongatum and either P. tejerai or P. (Haemamoeba) sp. that were compatible with P. tejerai but could not be confirmed. In total, 32% (9/28) penguins died over the course of 16 days despite oral treatment with chloroquine followed by sulfadiazine-trimethoprim. Hemosporidian infections were considered likely to have occurred during rehabilitation, probably from mosquitoes infected while feeding on local native birds, whereas penguin-mosquito-penguin transmission may have played a role in later stages of the outbreak. Considering the seasonality of the infection, rehabilitation centers would benefit from narrowing their efforts to prevent avian malaria outbreaks to the penguins that are maintained throughout summer.
Free Article
PMID: 24736326 [PubMed - in process]

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6. Br Poult Sci. 2014 Apr 16. [Epub ahead of print]

Effect of feeding diets based on coarse maize on productive performance, gizzard development and energy utilisation of laying hens.

Singh Y1, Rama Rao SV, Ravindran V.Author information:
1a Institute of Veterinary and Animal and Biomedical Sciences , Massey University , Palmerston North 4442 , New Zealand.

Abstract

Abstract 1. A total of 2200 White Leghorn layers were used to study the effect of feeding coarse maize on productive performance, gizzard weight, apparent metabolisable energy (AME) and egg quality parameters. 2. The experiment was a completely randomised design with 5 treatments, each being replicated 5 times (88 birds per replicate). Dietary treatments included a control diet with 600 g/kg of ground maize (6 mm sieve) and experimental diets with 150, 300, 450 or 600 g/kg coarse maize (10 mm sieve) replacing (w/w) ground maize. Diets, in mash form, were offered from 39 to 62 weeks of age. 3. Over the entire experimental period, dietary treatments had no effect on any of the production parameters, except on feed intake. A quadratic effect was observed for feed intake where intake increased at 150 g/kg coarse maize inclusion. At higher inclusion levels of coarse maize, feed intake was similar to that of the control diet. But the differences in daily intake between dietary treatments were only around 1 g/bird and may not be of any biological significance. 4. Dietary treatments had no effect on gizzard weight, AME or egg quality. 5. The results indicate that coarse maize could completely replace maize in layer diets with no adverse effect on egg production, egg quality and dietary energy utilisation. In the current work, although the proportion of coarse particles (over 1 mm) increased with increasing inclusion levels of coarse maize, the differences in the percentage of particles above 1 mm between the fine control (0 g/kg coarse maize) and coarsest (600 g/kg coarse maize) diets was only 15% and this may limit the value of the findings reported herein.
PMID: 24735428 [PubMed - as supplied by publisher]

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7. Philos Trans R Soc Lond B Biol Sci. 2014 Apr 14;369(1643):20130197. doi: 10.1098/rstb.2013.0197. Print 2014.

Modelling avian biodiversity using raw, unclassified satellite imagery.

St-Louis V1, Pidgeon AM, Kuemmerle T, Sonnenschein R, Radeloff VC, Clayton MK, Locke BA, Bash D, Hostert P.Author information:
1Department of Forest and Wildlife Ecology, University of Wisconsin-Madison, Madison, WI, USA.

Abstract

Applications of remote sensing for biodiversity conservation typically rely on image classifications that do not capture variability within coarse land cover classes. Here, we compare two measures derived from unclassified remotely sensed data, a measure of habitat heterogeneity and a measure of habitat composition, for explaining bird species richness and the spatial distribution of 10 species in a semi-arid landscape of New Mexico. We surveyed bird abundance from 1996 to 1998 at 42 plots located in the McGregor Range of Fort Bliss Army Reserve. Normalized Difference Vegetation Index values of two May 1997 Landsat scenes were the basis for among-pixel habitat heterogeneity (image texture), and we used the raw imagery to decompose each pixel into different habitat components (spectral mixture analysis). We used model averaging to relate measures of avian biodiversity to measures of image texture and spectral mixture analysis fractions. Measures of habitat heterogeneity, particularly angular second moment and standard deviation, provide higher explanatory power for bird species richness and the abundance of most species than measures of habitat composition. Using image texture, alone or in combination with other classified imagery-based approaches, for monitoring statuses and trends in biological diversity can greatly improve conservation efforts and habitat management.
PMID: 24733952 [PubMed - in process]

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8. Philos Trans R Soc Lond B Biol Sci. 2014 Apr 14;369(1643):20130195. doi: 10.1098/rstb.2013.0195. Print 2014.

Environmental drivers of variability in the movement ecology of turkey vultures (Cathartes aura) in North and South America.

Dodge S1, Bohrer G, Bildstein K, Davidson SC, Weinzierl R, Bechard MJ, Barber D, Kays R, Brandes D, Han J, Wikelski M.Author information:
1Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, , 475 Hitchcock Hall, 2070 Neil Avenue, Columbus, OH 43210, USA.

Abstract

Variation is key to the adaptability of species and their ability to survive changes to the Earth's climate and habitats. Plasticity in movement strategies allows a species to better track spatial dynamics of habitat quality. We describe the mechanisms that shape the movement of a long-distance migrant bird (turkey vulture, Cathartes aura) across two continents using satellite tracking coupled with remote-sensing science. Using nearly 10 years of data from 24 satellite-tracked vultures in four distinct populations, we describe an enormous amount of variation in their movement patterns. We related vulture movement to environmental conditions and found important correlations explaining how far they need to move to find food (indexed by the Normalized Difference Vegetation Index) and how fast they can move based on the prevalence of thermals and temperature. We conclude that the extensive variability in the movement ecology of turkey vultures, facilitated by their energetically efficient thermal soaring, suggests that this species is likely to do well across periods of modest climate change. The large scale and sample sizes needed for such analysis in a widespread migrant emphasizes the need for integrated and collaborative efforts to obtain tracking data and for policies, tools and open datasets to encourage such collaborations and data sharing.
PMID: 24733950 [PubMed - in process]

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9. Environ Toxicol Chem. 2014 Apr 15. doi: 10.1002/etc.2609. [Epub ahead of print]

Contaminant exposure of birds nesting in Green Bay, Wisconsin.

Custer TW1, Dummer PM, Custer CM, Franson JC, Jones M .Author information:
1US Geological Survey, La Crosse, Wisconsin, USA.

Abstract

In earlier studies, elevated polychlorinated biphenyl (PCB) and p,p'-dichlorodiphenyldichloroethylene (DDE) concentrations were reported in double-crested cormorant (Phalacrocorax auritus) eggs and tree swallow (Tachycineta bicolor) eggs and nestlings collected from lower Green Bay in 1994 and 1995 and black-crowned night-heron (Nycticorax nycticorax) eggs collected in 1991. Comparable samples collected in 2010 and 2011 indicated that concentrations of PCBs were 35%, 62%, 70%, and 88% lower than in the early 1990s in tree swallow eggs, tree swallow nestlings, double-crested cormorant eggs, and black-crowned night-heron eggs, respectively; concentrations of DDE were 47%, 43%, 51% and 80% lower, respectively. These declines are consistent with regional contaminant trends in other species. Concentrations of PCBs were higher in herring gull (Larus argentatus) than black-crowned night-heron eggs collected from Green Bay in 2010; PCB concentrations in double-crested cormorant and tree swallow eggs were intermediate. The estimated toxicity of the PCB mixture was equal or greater in eggs of the insectivorous tree swallow than the three piscivorous bird species. A multivariate analysis indicated that the percent composition of lower numbered PCB congeners was greater in eggs of the insectivorous tree swallow than in eggs of the three piscivorous species nesting in Green Bay. Dioxin and furan concentrations and the toxicity of these chemicals were also higher in tree swallows than these other waterbird species nesting in Green Bay. Environ Toxicol Chem © 2014 SETAC.
© 2014 SETAC.
PMID: 24733712 [PubMed - as supplied by publisher]






10. Glob Chang Biol. 2014 Apr 11. doi: 10.1111/gcb.12573. [Epub ahead of print]

Patterns of climate-induced density shifts of species: poleward shifts faster in northern boreal birds than in southern birds.

Virkkala R1, Lehikoinen A.Author information:
1Finnish Environment Institute, Natural Environment Centre, Mechelininkatu 34 a, P.O. Box 140, Helsinki, FI-00251, Finland.

Abstract

Climate change has been shown to cause poleward range shifts of species. These shifts are typically demonstrated using presence-absence data, which can mask the potential changes in the abundance of species. Moreover, changes in the mean centre of weighted density of species are seldom examined, and comparisons between these two methods are even rarer. Here, we studied the change in the mean weighted latitude of density (MWLD) of 94 bird species in Finland, northern Europe, using data covering a north-south gradient of over 1000 km from the 1970s to the 2010s. The MWLD shifted northward on average 1.26 km yr-1 , and this shift was significantly stronger in northern species compared to southern species. These shifts can be related to climate warming during the study period, because the annual temperature had increased more in northern Finland (by 1.7 °C) than in southern Finland (by 1.4 °C), although direct causal links cannot be shown. Density shifts of species distributed over the whole country did not differ from shifts in species situated on the edge of the species range in southern and northern species. This means that density shifts occur both in the core and on the edge of species distribution. The species-specific comparison of MWLD values with corresponding changes in the mean weighted latitude using presence-absence atlas data (MWL) revealed that the MWLD moved more slowly than the MWL in the atlas data in the southern species examined, but more rapidly in the northern species. Our findings highlight that population densities are also moving rapidly towards the poles and the use of presence-absence data can mask the shift of population densities. We encourage use of abundance data in studies considering the effects of climate change on biodiversity.
© 2014 John Wiley & Sons Ltd.
PMID: 24729475 [PubMed - as supplied by publisher]

11. Environ Monit Assess. 2014 Apr 12. [Epub ahead of print]

The distribution and extent of heavy metal accumulation in song sparrows along Arizona's upper Santa Cruz River.

Lester MB1, van Riper C 3rd.Author information:
1School of Natural Resources and the Environment, The University of Arizona, 1110 E. South Campus Dr., Room 123, Tucson, AZ, 85721, USA, mlester126@gmail.com.

Abstract

Heavy metals are persistent environmental contaminants, and transport of metals into the environment poses a threat to ecosystems, as plants and wildlife are susceptible to long-term exposure, bioaccumulation, and potential toxicity. We investigated the distribution and cascading extent of heavy metal accumulation in southwestern song sparrows (Melospiza melodia fallax), a resident riparian bird species that occurs along the US/Mexico border in Arizona's upper Santa Cruz River watershed. This study had three goals: (1) quantify the degree of heavy metal accumulation in sparrows and determine the distributional patterns among study sites, (2) compare concentrations of metals found in this study to those found in studies performed prior to a 2009 international wastewater facility upgrade, and (3) assess the condition of song sparrows among sites with differing potential levels of exposure. We examined five study sites along with a reference site that reflect different potential sources of contamination. Body mass residuals and leukocyte counts were used to assess sparrow condition. Birds at our study sites typically had higher metal concentrations than birds at the reference site. Copper, mercury, nickel, and selenium in song sparrows did exceed background levels, although most metals were below background concentrations determined from previous studies. Song sparrows generally showed lower heavy metal concentrations compared to studies conducted prior to the 2009 wastewater facility upgrade. We found no cascading effects as a result of metal exposure.
PMID: 24729180 [PubMed - as supplied by publisher]


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12. Ecotoxicology. 2014 Apr 12. [Epub ahead of print]

Design, development and demonstration of an improved bird washing machine.

Rajabi H1, Monsef H, Moghadami M, Zare M, Armandei A.Author information:
1Department of Mechanical Engineering, Ahrar Institute of Technology and Higher Education, Rasht, Iran, harajabi@hotmail.com.

Abstract

Since oil was first extracted, pollution of the seas and oceans or adjacent coasts has been an obstacle for the oil industry and environmental activists. The major concern is oil discharge into the water which may lead to birds' affliction or death, besides putting marine life in jeopardy. This paper presents the first description of the design and implementation of a new bird washing machine that can be utilized for cleaning of oil-coated birds with the minimum of stress. The machine is equipped with a pneumatic system comprised of 19 moving nozzles which evenly cover the bird's body and is designed to be used in contaminated environments where a vast number of birds are affected. Experimental trials show an improvement in operation efficiency compared to other methods in a reduction in washing time, energy consumption and a decrease in fatality rate of washed birds.
PMID: 24729024 [PubMed - as supplied by publisher]

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13. Environ Int. 2014 Apr 8;68C:118-126. doi: 10.1016/j.envint.2014.03.013. [Epub ahead of print]

Bioaccumulation and biomagnification of emerging and classical flame retardants in bird eggs of 14 species from Doñana Natural Space and surrounding areas (South-western Spain).

Barón E1, Máñez M2, Andreu AC2, Sergio F3, Hiraldo F3, Eljarrat E4, Barceló D5.Author information:
1Water and Soil Quality Research Group, Department of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain.
2Natural Processes Monitoring Team, Estación Biológica de Doñana (EBD-CSIC), c/Américo Vespucio s/n, 41092 Seville, Spain.
3Department of Applied Biology, Doñana Biological Station (EBD-CSIC), Sevilla, Spain.
4Water and Soil Quality Research Group, Department of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain. Electronic address: eeeqam@cid.csic.es.
5Water and Soil Quality Research Group, Department of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain; Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain.

Abstract

The occurrence of classical (polybrominated diphenyl ethers, PBDEs) and emerging FRs (dechloranes, hexabromobenzene (HBB), pentabromoethyl benzene (PBEB) and decabromodiphenyl ethane (DBDPE)) in unborn eggs of 14 different species from Doñana Natural Space and surrounding areas was studied. PBDEs, Dec-602, Dec-603 and DP were detected in all the species, whereas HBB, PBEB, DBDPE and Dec-604 were not detected in any sample. ΣPBDE and ΣDechlorane levels ranged from 1.40 to 90.7, and from 0.77 to 260ng/glw, respectively. BDE-209 was the most abundant BDE congener in almost all the species, whereas Dec-602 was the predominant among dechloranes. In general, levels of PBDEs and dechloranes were similar and even higher for dechloranes, probably indicating the increasing use of dechloranes as a result of legal restrictions on PBDEs. In both cases, the most contaminated specie was the white stork. Using stable isotope characterization, differences among species and possible biomagnification processes were also evaluated. PBDE levels increased as the trophic position increased, showing biomagnification capacity. The same behavior was observed for Dec-602 and Dec-603; however, DP levels were not linearly correlated with trophic level. These results show that more attention should be given to emerging FRs such as dechloranes since they show similar environmental behavior as PBDEs.
Copyright © 2014 Elsevier Ltd. All rights reserved.
PMID: 24727066 [PubMed - as supplied by publisher]


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14. Curr Biol. 2014 Apr 9. pii: S0960-9822(14)00270-X. doi: 10.1016/j.cub.2014.03.011. [Epub ahead of print]

Global Distribution and Conservation of Evolutionary Distinctness in Birds.

Jetz W1, Thomas GH2, Joy JB3, Redding DW4, Hartmann K5, Mooers AO6.Author information:
1Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect Street, New Haven, CT 06520-8106, USA; Department of Life Sciences, Imperial College London, Silwood Park Campus, Ascot SL5 7PY, UK. Electronic address: walter.jetz@yale.edu.
2Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
3Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect Street, New Haven, CT 06520-8106, USA; Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada; BC Centre for Excellence in HIV/AIDS, Vancouver, BC V6Z 1Y6, Canada.
4Centre for Biodiversity and Environment Research, Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK.
5Institute for Marine and Antarctic Studies, University of Tasmania, Private Bag 49, Hobart, TAS 7001, Australia.
6Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada. Electronic address: amooers@sfu.ca.

Abstract

BACKGROUND:

Integrated, efficient, and global prioritization approaches are necessary to manage the ongoing loss of species and their associated function. "Evolutionary distinctness" measures a species' contribution to the total evolutionary history of its clade and is expected to capture uniquely divergent genomes and functions. Here we demonstrate how such a metric identifies species and regions of particular value for safeguarding evolutionary diversity.

RESULTS:

Among the world's 9,993 recognized bird species, evolutionary distinctness is very heterogeneously distributed on the phylogenetic tree and varies little with range size or threat level. Species representing the most evolutionary history over the smallest area (those with greatest "evolutionary distinctness rarity") as well as some of the most imperiled distinct species are often concentrated outside the species-rich regions and countries, suggesting they may not be well captured by current conservation planning. We perform global cross-species and spatial analyses and generate minimum conservation sets to assess the benefits of the presented species-level metrics. We find that prioritizing imperiled species by their evolutionary distinctness and geographic rarity is a surprisingly effective and spatially economical way to maintain the total evolutionary information encompassing the world's birds. We identify potential conservation gaps in relation to the existing reserve network that in particular highlight islands as effective priority areas.

CONCLUSIONS:

The presented distinctness metrics are effective yet easily communicable and versatile tools to assist objective global conservation decision making. Given that most species will remain ecologically understudied, combining growing phylogenetic and spatial data may be an efficient way to retain vital aspects of biodiversity.
Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.
PMID: 24726155 [PubMed - as supplied by publisher]

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15. Front Zool. 2014 Apr 12;11(1):33. doi: 10.1186/1742-9994-11-33.

New developmental evidence supports a homeotic frameshift of digit identity in the evolution of the bird wing.

Salinas-Saavedra M, Gonzalez-Cabrera C, Ossa-Fuentes L, Botelho JF, Ruiz-Flores M, Vargas AO1.Author information:
1Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago, Chile. thearchosaur@gmail.com.

Abstract

BACKGROUND:

The homology of the digits in the bird wing is a high-profile controversy in developmental and evolutionary biology. The embryonic position of the digits cartilages with respect to the primary axis (ulnare and ulna) corresponds to 2, 3, 4, but comparative-evolutionary morphology supports 1, 2, 3. A homeotic frameshift of digit identity in evolution could explain how cells in embryonic positions 2, 3, 4 began developing morphologies 1, 2, 3. Another alternative is that no re-patterning of cell fates occurred, and the primary axis shifted its position by some other mechanism. In the wing, only the anterior digit lacks expression of HoxD10 and HoxD12, resembling digit 1 of other limbs, as predicted by 1, 2, 3. However, upon loss of digit 1 in evolution, the most anterior digit 2 could have lost their expression, deceitfully resembling a digit 1. To test this notion, we observed HoxD10 and HoxD12 in a limb where digit 2 is the most anterior digit: The rabbit foot. We also explored whether early inhibition of Shh signalling in the embryonic wing bud induces an experimental homeotic frameshift, or an experimental axis shift. We tested these hypotheses using DiI injections to study the fate of cells in these experimental wings.

RESULTS:

We found strong transcription of HoxD10 and HoxD12 was present in the most anterior digit 2 of the rabbit foot. Thus, we found no evidence to question the use of HoxD expression as support for 1, 2, 3. When Shh signalling in early wing buds is inhibited, our fate maps demonstrate that an experimental homeotic frameshift is induced.

CONCLUSION:

Along with comparative morphology, HoxD expression provides strong support for 1, 2, 3 identity of wing digits. As an explanation for the offset 2, 3, 4 embryological position, the homeotic frameshift hypothesis is consistent with known mechanisms of limb development, and further proven to be experimentally possible. In contrast, the underlying mechanisms and experimental plausibility of an axis shift remain unclear.
PMCID: PMC3986427 Free PMC Article
PMID: 24725625 [PubMed]

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