scholarly journals Pachytene karyotypes of 17 species of birds

2022 ◽  
Author(s):  
Anastasia Slobodchikova ◽  
Lyubov Malinovskaya ◽  
Ekaterina Grishko ◽  
Inna Pristyazhnyuk ◽  
Anna Torgasheva ◽  
...  
Keyword(s):  
Chromosome Numbers ◽  
Bird Species ◽  
Passerine Bird ◽  
Published Data ◽  
Metaphase Chromosomes ◽  
Meiotic Chromosomes ◽  
Passerine Species ◽  
Centromere Proteins ◽  
Outgroup Species ◽  
Gouldian Finch

Background: To date less than 10% of bird species have been karyotyped. They are rather conservative with diploid chromosome numbers about 78-80 in most species examined. Immunostaining of meiotic chromosomes at pachytene stage enables more precise estimates of the number, morphology and variability of macro- and microchromosomes than conventional analysis of mitotic metaphase chromosomes does. Analysis of pachytene chromosomes led to discovery of germline-restricted chromosome (GRC) that was present in germline cells and absent in somatic cells in all 16 species of passerine birds examined. GRC has not been found in any non-passerine bird. Results: In this study, using immunolocalization of SYCP3, the main protein of the lateral elements of the synaptonemal complex (SC) and centromere proteins we examined male pachytene karyotypes of sixteen passerine species and one outgroup species the Common cuckoo Cuculus canorus and provided their idiograms and precise estimates of their diploid chromosome numbers and the numbers of chromosome arms. We provided the first description of the karyotypes of three species, corrected the published data on the karyotypes of ten species and confirmed them for four species. The pachytene cells of the Gouldian finch, Brambling and Common linnet contained heteromorphic bivalents indicating heterozygosity for inversions or centromere shifts. The European pied flycatcher, Gouldian finch and Domestic canary have extended centromeres in several macro- and microchromosomes. GRCs of various sizes and shapes were detected in all passerine species examined. Their chromatin was heavily labeled by anticentromere antibodies. The lateral elements of the GRC SC varied in their size from the largest to the smallest element of the pachytene karyotype. They also varied in shape from continuous to fragmented. Conclusions: All songbirds examined, except the Eurasian skylark, have highly conservative karyotypes, 2n=80-82+GRC with seven pairs of macrochromosomes and 33-34 pairs of microchromosomes. The interspecies differences concern the sizes of the macrochromosomes, morphology of the microchromosomes and sizes of the centromeres. GRC is present in all songbird species examined, varying in size, morphology and SC structure even between closely related species. This indicates its fast evolution.

scholarly journals Limited reproductive impairment in a passerine bird species exposed along a perfluoroalkyl acid (PFAA) pollution gradient

2019 ◽  
Vol 652 ◽  
pp. 718-728 ◽  
Author(s):  
Thimo Groffen ◽  
Robin Lasters ◽  
Ana Lopez-Antia ◽  
Els Prinsen ◽  
Lieven Bervoets ◽  
...  
Keyword(s):  
Bird Species ◽  
Passerine Bird ◽  
Pollution Gradient ◽  
Reproductive Impairment ◽  
Perfluoroalkyl Acid

scholarly journals Nepal’s National Red List of Birds

2017 ◽  
Vol 9 (1) ◽  
pp. 9700 ◽  
Author(s):  
Carol Inskipp ◽  
Hem Sagar Baral ◽  
Tim Inskipp ◽  
Ambika Prasad Khatiwada ◽  
Monsoon Pokharel Khatiwada ◽  
...  
Keyword(s):  
Endangered Species ◽  
Biological Diversity ◽  
Conservation Status ◽  
Bird Species ◽  
Convention On Biological Diversity ◽  
Wetland Birds ◽  
Distribution Maps ◽  
Critically Endangered Species ◽  
Passerine Species ◽  
Over Exploitation

The main objectives of the Nepal National Bird Red Data Book were to provide comprehensive and up-to-date accounts of all the bird species found in Nepal, assess their status applying the IUCN Guidelines at Regional Levels, identify threats to all bird species and recommend the most practical measures for their conservation.  It is hoped that the Bird RDB will help Nepal achieve the Convention on Biological Diversity target of preventing the extinction of known threatened species and improving their conservation status.  As population changes of Nepal’s birds have been studied for only a few species, assessments of species’ national status were mainly made by assessing changes in distribution.  Species distribution maps were produced for all of Nepal’s bird species except vagrants and compared to maps that were produced in 1991 using the same mapping system.  Of the 878 bird species recorded, 168 species (19%) were assessed as nationally threatened. These comprise 68 (40%) Critically Endangered species, 38 (23%) Endangered species and 62 (37%) Vulnerable species.  A total of 62 species was considered Near Threatened and 22 species Data Deficient.  Over 55% of the threatened birds are lowland grassland specialists, 25% are wetland birds and 24% tropical and sub-tropical broadleaved forest birds.  Larger birds appear to be more threatened than smaller birds with 98 (25%) non-passerine species threatened and 67 (14%) passerine species.  Habitat loss, degradation and fragmentation are the most important threats.  Other threats include chemical poisoning, over-exploitation, climate change, hydropower, invasive species, intensification of agriculture, disturbance, and limited conservation measures and research.  Measures to address these threats are described.  It was also concluded that re-assessments of the status of certain bird groups carried out every five years and the setting up of a national online system for storing and reporting bird sightings would be useful.

scholarly journals Introducing the Bird Chromosome Database: An Overview of Cytogenetic Studies in Birds

2020 ◽  
Vol 160 (4) ◽  
pp. 199-205 ◽  
Author(s):  
Tiago M. Degrandi ◽  
Suziane A. Barcellos ◽  
Alice L. Costa ◽  
Analía D.V. Garnero ◽  
Iris Hass ◽  
...  
Keyword(s):  
Chromosome Numbers ◽  
Chromosome Painting ◽  
Bird Species ◽  
Extensive Literature ◽  
Phylogenetic Studies ◽  
Cytogenetic Studies ◽  
History Of ◽  
Intrachromosomal Rearrangements ◽  
Painting Probes ◽  
Whole Chromosome Painting

Bird chromosomes, which have been investigated scientifically for more than a century, present a number of unique features. In general, bird karyotypes have a high diploid number (2n) of typically around 80 chromosomes that are divided into macro- and microchromosomes. In recent decades, FISH studies using whole chromosome painting probes have shown that the macrochromosomes evolved through both inter- and intrachromosomal rearrangements. However, chromosome painting data are available for only a few bird species, which hinders a more systematic approach to the understanding of the evolutionary history of the enigmatic bird karyotype. Thus, we decided to create an innovative database through compilation of the cytogenetic data available for birds, including chromosome numbers and the results of chromosome painting with chicken (Gallus gallus) probes. The data were obtained through an extensive literature review, which focused on cytogenetic studies published up to 2019. In the first version of the “Bird Chromosome Database (BCD)” (https://sites.unipampa.edu.br/birdchromosomedatabase) we have compiled data on the chromosome numbers of 1,067 bird species and chromosome painting data on 96 species. We found considerable variation in the diploid numbers, which ranged from 40 to 142, although most (around 50%) of the species studied up to now have between 78 and 82 chromosomes. Despite its importance for cytogenetic research, chromosome painting has been applied to less than 1% of all bird species. The BCD will enable researchers to identify the main knowledge gaps in bird cytogenetics, including the most under-sampled groups, and make inferences on chromosomal homologies in phylogenetic studies.

Winter Ecological Energetics of 2 Passerine Bird Species in Temperate Wet Forest

1988 ◽  
Vol 15 (3) ◽  
pp. 319 ◽  
Author(s):  
J Haylock ◽  
a Lill
Keyword(s):  
Bird Species ◽  
Metabolic Cost ◽  
Passerine Bird ◽  
Foraging Efficiency ◽  
Energy Budgets ◽  
Similar Time ◽  
Energy Expenditures ◽  
Eastern Australia ◽  
Temperate Birds ◽  
Winter Time

Autumn and winter time-energy budgets were constructed for brown thornbills, Acanthiza pusilla, and eastern yellow robins, Eopsaltria australis, inhabiting a temperate wet forest in south-eastern Australia. Birds spent 84-88% of daylight hours foraging in both seasons, but decreased the metabolic cost of other activity in winter by spending more time on energetically inexpensive behaviours. Estimated daily energy expenditures were either seasonally constant or increased (thornbill) or decreased (robin) in winter by no nore than l0%, depending on the assumed degree of substitution for the thermoregulatory requirement. Thornbills increased foraging efficiency in winter to compensate for the reduction in absolute foraging time. Less dramatic changes in behavioural strategies were required to achieve energy balance than have been recorded for many small north temperate birds. Brown thornbills used an energetically expensive, active search foraging technique to capture small, cryptic prey at a fast rate. Yellow robins employed an inexpensive, 'sit-and-wait' strategy to capture larger, more conspicuous prey at a slower rate. Both species had similar time investments in foraging, but allocated greatly differing proportions of energy to active foraging and resting alert. These contrasting strategies offer the potential for performing several activities simultaneously in the yellow robin and for reducing foraging and vigilance investments through exploiting gregariousness in the brown thornbill.

scholarly journals Anti-predator behavior along elevational and latitudinal gradients in dark-eyed juncos

2019 ◽  
Vol 66 (3) ◽  
pp. 239-245 ◽  
Author(s):  
Madelin Andrade ◽  
Daniel T Blumstein
Keyword(s):  
Human Impacts ◽  
Bird Species ◽  
Passerine Bird ◽  
Latitudinal Gradients ◽  
Junco Hyemalis ◽  
Predator Density ◽  
Elevational Gradients ◽  
Main Driver ◽  
Flight Initiation ◽  
Predator Behavior

Abstract Flight-initiation distance (FID), the distance between an individual and experimenter when it begins to flee, can be used to quantify risk-assessment. Among other factors, prior studies have shown that latitude explains significant variation in avian FID: at lower latitudes, individuals and species have longer FIDs than those living at higher latitudes. No prior studies have focused on the effect of elevation on FID. Given the similar patterns of seasonality, climate, and potentially predator density, that covary between latitude and elevation, birds at higher elevations might tolerate closer approaches. We asked whether elevation or latitude would explain more variation in the FID of a common passerine bird species, dark-eyed juncos (Junco hyemalis). Juncos live in a variety of habitats along both latitudinal and elevational gradients. We found that statistical models containing elevation as a variable explained more of the variation in FID than did models containing latitude. We also found, unexpectedly, that birds at higher elevation fled at greater distances. While more predators were sighted per hour at higher elevations than at lower elevations, the frequency of predator sightings did not explain a significant amount of variation in FID. This result questions whether predator density is the main driver of risk perception along elevational gradients. Nonetheless, because elevation explains more variation in FID than latitude in at least one species, these findings have direct implications on how human impacts on birds are managed. Specifically, those designing set-back zones to reduce human impact on birds may consider modifying them based on both latitude and elevation.

scholarly journals Stress, Metabolism, and Antioxidants in Two Wild Passerine Bird Species

2008 ◽  
Vol 81 (4) ◽  
pp. 463-472 ◽  
Author(s):  
Alan A. Cohen ◽  
Michaela Hau ◽  
Martin Wikelski
Keyword(s):  
Bird Species ◽  
Passerine Bird
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