scholarly journals Genetic determination of migration strategies in large soaring birds: evidence from hybrid eagles

2018 ◽  
Vol 285 (1884) ◽  
pp. 20180855 ◽  
Author(s):  
Ülo Väli ◽  
Paweł Mirski ◽  
Urmas Sellis ◽  
Mindaugas Dagys ◽  
Grzegorz Maciorowski
Keyword(s):  
Bird Species ◽  
Migration Strategy ◽  
Genetic Determination ◽  
Timing Of Migration ◽  
Habitat Suitability Modelling ◽  
Migration Strategies ◽  
Soaring Birds ◽  
Genetically Determined ◽  
Migratory Movements

The relative contributions of genetic and social factors in shaping the living world are a crucial question in ecology. The annual migration of birds to their wintering grounds and back provides significant knowledge in this field of research. Migratory movements are predominantly genetically determined in passerine birds, while in large soaring birds, it is presumed that social (cultural) factors play the largest role. In this study, we show that genetic factors in soaring birds are more important than previously assumed. We used global positioning system (GPS)-telemetry to compare the autumn journeys and wintering ranges of two closely related large raptorial bird species, the greater spotted eagle Clanga clanga and the lesser spotted eagle Clanga pomarina , and hybrids between them. The timing of migration in hybrids was similar to that of one parental species, but the wintering distributions and home range sizes were similar to those of the other. Tracking data were supported by habitat suitability modelling, based on GPS fixes and ring recoveries. These results suggest a strong genetic influence on migration strategy via a trait-dependent dominance effect, although we cannot rule out the contribution of social interactions.

GENETICS AND METABOLISM

PEDIATRICS ◽  
1960 ◽  
Vol 25 (4) ◽  
pp. 565-571
Author(s):  
Barton Childs
Keyword(s):  
Mutant Gene ◽  
Human Populations ◽  
Affected Patient ◽  
Adrenal Hyperplasia ◽  
Genetic Determination ◽  
The Subject ◽  
Definition Of ◽  
Genetically Determined ◽  
Or Genes

IT IS the part of wisdom when about to give a dissertation which one hopes will at once instruct and entertain, to provide at the outset some definition of the subject matter. Genetics is the study of the heritable components of variation; the heritable factors which determine the range or extent of diversity. So, genetics is concerned with heritable differences and likenesses between individuals and between species. One emphasizes the differences because one can be certain of genetic determination of a particular characteristic only when it exists in a population in two or more alternative forms. It is the variants which catch the eye and hold the attention of the investigator, and which by their presence suggest more than one form of the gene or genes which determine that particular characteristic. I would like in what follows to present some examples of investigations of some aspects of genetics in human populations. ADRENAL HYPERPLASIA Several years ago Dr. Melvin Grumbach and I studied the genetics of adrenal hyperplasia, using as our material the patients of Dr. Lawson Wilkins. Since the disease occurs in more than one member of a sibship and since parents are unaffected, we suspected that it was genetically determined and that the affected patient possessed a double dose of a mutant gene; that is, the characteristic was recessive.

Genetic Determination of Erect and Prostrate Growth Habit in Five Shrubs From Windswept Headlands in the Sydney Region

1992 ◽  
Vol 40 (1) ◽  
pp. 1 ◽  
Author(s):  
TD Auld ◽  
DA Morrison
Keyword(s):  
Growth Habit ◽  
Morphological Characteristics ◽  
Genetic Determination ◽  
Specific Variation ◽  
Banksia Ericifolia ◽  
Growth Habits ◽  
Genetically Determined ◽  
Different Characteristics ◽  
Prostrate Growth

In the Sydney region, many plants from populations on windswept headlands have a more prostrate growth habit compared with plants from populations of the same species occurring away from the coast. To determine whether these different growth habits are genetically determined, plants from four populations of each of five species (Acacia rnyrtifolia, Acacia suaveolens, Banksia ericifolia, Casuarina distyla, Hakea teretifolia) were grown under uniform glasshouse conditions. Multivariate analyses of six morphological characteristics indicate that, for four of these species, the offspring are similar to their maternal parent; we thus conclude that the habit differences are genetically fixed in these populations. The same trend is apparent for <I.C. distyla , although significant variation occurs in the offspring. Univariate analyses indicate that different characteristics reflect the habit differences in different species. For conservation biology, the implications of this intra-specific variation are that attempts should be made to conserve viable populations of all genetically isolated taxa within a species.

scholarly journals The Use of Nocturnal Flights for Barrier Crossing in a Diurnally Migrating Songbird: Implications for Our Understanding of Fly-and-Forage Migration Strategies

2020 ◽  
Author(s):  
Christie D. Lavallée ◽  
Saeedeh Bani Assadi ◽  
Alicia M. Korpach ◽  
James D. Ray ◽  
Jason D Fischer ◽  
...  
Keyword(s):  
Open Water ◽  
Gps Tracking ◽  
Migration Strategy ◽  
Barrier Crossing ◽  
Migration Patterns ◽  
Migration Strategies ◽  
The Caribbean ◽  
Migratory Movements ◽  
High Degree ◽  
Circadian Patterns

Abstract Background: The migration patterns of land birds can generally be divided into those species that migrate principally during the day and those that migrate during the night. Some species may show individual plasticity in the use of day or night flight, particularly when crossing large, open-water or desert barriers. However, individual plasticity in circadian patterns of migratory flights in diurnal songbirds that use a fly-and-forage migration strategy has never been investigated. Methods: We used high precision GPS tracking of a diurnal, migratory swallow Purple martin, (Progne subis), to determine whether individuals were flexible in their spring migration strategies to include some night flight, particularly at barrier crossing.Results: We found that individuals made large (sometimes >1000 km), open-water crossings of the Caribbean Sea and the Gulf of Mexico that included the use of night flight. Some birds-initiated barrier crossing flights at night, demonstrating that night flight is not only used to complete barrier crossings but may confer other advantages for diurnal birds. All birds also used some, shorter night flights when making overland flights not associated with barrier crossing. Birds were more likely to initiate water crossings with supportive northward winds, and preliminary data suggest that moonlight may influence nighttime migratory movements.Conclusions: Overall, our results demonstrate an unexpected high degree of individual plasticity in migration strategies on a circadian scale in a ‘diurnal’ songbird and suggest that barrier crossing at night may complement fly-and-forage migration strategies.

Screening of Infectious Causes of Diarrhea and Genetic Determination of Diarrheagenic E. coli using Multiplex PCR in under 5 Years Children in Egypt

2020 ◽  
Vol EJMM29 (4) ◽  
pp. 27-34
Author(s):  
Yosra M. Hassan ◽  
Saha r M. Khairat ◽  
Nada N. Nawar ◽  
Maha M. Gaafar ◽  
Dina M Hassan ◽  
...  
Keyword(s):  
Multiplex Pcr ◽  
Infectious Diarrhea ◽  
Genetic Determination ◽  
E Coli ◽  
Single Positive ◽  
Life Threatening ◽  
Stool Specimens ◽  
Genetically Determined ◽  
Microbiological Procedures

Background: Infectious diarrhea represents a life-threatening problem among children in developing countries. Objectives: This work aimed to study bacterial, viral and parasitic causes of acute diarrhea; with genetic determination of diarrheagenic E. coli (DEC) in <5 years children. Methodology: Stool specimens were collected from 206 diarrheal children. Bacterial agents were isolated and identified by standard microbiological procedures. Multiplex PCR was done for genetic determination of DEC subtypes. ELISA was used for detection of viral and parasitic agents. Results: Stool specimens with at least single positive enteropathogen accounted for 98.5% with bacterial, viral and parasitic rates of 98.5%, 42.7% and 25.2%, respectively. Isolated bacteria were DEC (98.5%); Campylobacter (14%), Shigella (3.8%) and Salmonella (1.4%). Rota and Noroviruses showed prevalence of 32.5% and 5.3%, respectively. Conclusion: Infectious diarrhea were mostly due to bacterial agents. DEC and Campylobacter were predominant. EAEC and EPEC were the most genetically determined DEC subtypes.

scholarly journals Population trends of common breeding and wintering birds in Hungary, decline of longdistance migrant and farmland birds during 1999–2012

2012 ◽  
Vol 20 (2) ◽  
pp. 13-63 ◽  
Author(s):  
Tibor Szép ◽  
Károly Nagy ◽  
Zsolt Nagy ◽  
Gergő Halmo
Keyword(s):  
Bird Species ◽  
Population Trends ◽  
Farmland Birds ◽  
Long Distance ◽  
Migration Strategy ◽  
Central Eastern Europe ◽  
Bird Monitoring ◽  
Biogeographical Region ◽  
Migration Strategies ◽  
Common Birds

Abstract Based on the Hungarian common bird monitoring scheme (MMM), which is the longest running country-wide monitoring using formal sampling design with representative data for the main habitats in Central-Eastern Europe, we investigated the population trends of common breeding and wintering species. Habitat preference and occupancy of the common breeders, migration strategies and relationships among these characteristics could act behind the population trends. We pointed out that long distance migrant bird species had strong decreasing trends in Hungary and very probably in the entire Pannonian biogeographical region, whereas the partial and short migrant species has increasing trends. Farmland birds had declining trend, which trend became more obvious since the joining of Hungary to the EU. The negative changes in the farmland habitat could influence bird species nesting/foraging mainly in this habitat independently from their migration strategies. Our investigations let us to develop indicators on the basis of migration strategy and habitat usage of common birds to provide regular information about condition of groups of species and their habitats in Hungary and the Pannonian region. The MMM database provide unique opportunity for further investigations of several species, habitats and area specific in a part of Europe where this kind of information is rare yet.

scholarly journals Prevalence and genetic diversity of avian haemosporidian parasites in wild bird species of the order Columbiformes

2021 ◽  
Author(s):  
Yvonne R. Schumm ◽  
Dimitris Bakaloudis ◽  
Christos Barboutis ◽  
Jacopo G. Cecere ◽  
Cyril Eraud ◽  
...  
Keyword(s):  
Host Species ◽  
Large Scale ◽  
Phylogenetic Reconstruction ◽  
Bird Species ◽  
Avian Species ◽  
Blood Parasites ◽  
Migration Strategy ◽  
Haemosporidian Parasites ◽  
Multiplex Pcr Assay ◽  
And Migration

AbstractDiseases can play a role in species decline. Among them, haemosporidian parasites, vector-transmitted protozoan parasites, are known to constitute a risk for different avian species. However, the magnitude of haemosporidian infection in wild columbiform birds, including strongly decreasing European turtle doves, is largely unknown. We examined the prevalence and diversity of haemosporidian parasites Plasmodium, Leucocytozoon and subgenera Haemoproteus and Parahaemoproteus in six species of the order Columbiformes during breeding season and migration by applying nested PCR, one-step multiplex PCR assay and microscopy. We detected infections in 109 of the 259 screened individuals (42%), including 15 distinct haemosporidian mitochondrial cytochrome b lineages, representing five H. (Haemoproteus), two H. (Parahaemoproteus), five Leucocytozoon and three Plasmodium lineages. Five of these lineages have never been described before. We discriminated between single and mixed infections and determined host species-specific prevalence for each parasite genus. Observed differences among sampled host species are discussed with reference to behavioural characteristics, including nesting and migration strategy. Our results support previous suggestions that migratory birds have a higher prevalence and diversity of blood parasites than resident or short-distance migratory species. A phylogenetic reconstruction provided evidence for H. (Haemoproteus) as well as H. (Parahaemoproteus) infections in columbiform birds. Based on microscopic examination, we quantified parasitemia, indicating the probability of negative effects on the host. This study provides a large-scale baseline description of haemosporidian infections of wild birds belonging to the order Columbiformes sampled in the northern hemisphere. The results enable the monitoring of future changes in parasite transmission areas, distribution and diversity associated with global change, posing a potential risk for declining avian species as the European turtle dove.

scholarly journals Seasonal differences in migration strategies of Red Kites (Milvus milvus) wintering in Spain

2021 ◽  
Author(s):  
Jorge García-Macía ◽  
Javier Vidal-Mateo ◽  
Javier De La Puente ◽  
Ana Bermejo ◽  
Rainer Raab ◽  
...  
Keyword(s):  
Spring Migration ◽  
Great Variability ◽  
Autumn Migration ◽  
Seasonal Differences ◽  
North Eastern ◽  
Wintering Areas ◽  
Satellite Transmitters ◽  
Migration Strategies ◽  
Migratory Movements ◽  
Milvus Milvus

AbstractRed Kite shows a great variability in its migration strategies: most individuals in north-eastern Europe are migrants, but there is also a growing number of sedentary individuals. Here, we tagged 49 Red Kites wintering in Spain with GPS/satellite transmitters between 2013 and 2020 to study the autumn and spring migration between the breeding or summering areas in Central Europe and the wintering quarters in Spain. In first place, differences between immatures and adults were found for spring migration. Adults began the spring migration towards the northeast in February–March while the immature individuals began to migrate significantly later and showing a wider date range (February-June). Adults also takes significantly less days to arrive at their destinations (12 ± 5 days) and cover more distance per day (134.2 ± 37.1 km/day) than immatures (19 ± 11 days and 98.9 ± 21.2 km/day). In second place, we also found differences between spring and autumn migration (excluding immatures). Spring migrations were clearly faster and with less stopovers days than autumn migrations. Autumn migration began between mid-October and late November and two different behaviours were observed: most birds made a quick migration direct to the wintering areas with only some days of stopovers, but others prolonged the migration with long stops along the route. These results highlight a great variation in the migratory movements of Red Kite, not only according to age but also between individuals and seasons.

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