scholarly journals Individual variability and versatility in an eco-evolutionary model of avian migration

2020 ◽  
Vol 287 (1938) ◽  
pp. 20201339
Author(s):  
Kira E. Delmore ◽  
Benjamin M. Van Doren ◽  
Greg J. Conway ◽  
Teja Curk ◽  
Tania Garrido-Garduño ◽  
...  
Keyword(s):  
Evolutionary Model ◽  
Individual Variability ◽  
Seasonal Migration ◽  
Migration Routes ◽  
Selection Gradient ◽  
Migration Direction ◽  
Wide Range ◽  
Breeding Grounds ◽  
In The Wild ◽  
Novel Strategy

Seasonal migration is a complex and variable behaviour with the potential to promote reproductive isolation. In Eurasian blackcaps ( Sylvia atricapilla ), a migratory divide in central Europe separating populations with southwest (SW) and southeast (SE) autumn routes may facilitate isolation, and individuals using new wintering areas in Britain show divergence from Mediterranean winterers. We tracked 100 blackcaps in the wild to characterize these strategies. Blackcaps to the west and east of the divide used predominantly SW and SE directions, respectively, but close to the contact zone many individuals took intermediate (S) routes. At 14.0° E, we documented a sharp transition from SW to SE migratory directions across only 27 (10–86) km, implying a strong selection gradient across the divide. Blackcaps wintering in Britain took northwesterly migration routes from continental European breeding grounds. They originated from a surprisingly extensive area, spanning 2000 km of the breeding range. British winterers bred in sympatry with SW-bound migrants but arrived 9.8 days earlier on the breeding grounds, suggesting some potential for assortative mating by timing. Overall, our data reveal complex variation in songbird migration and suggest that selection can maintain variation in migration direction across short distances while enabling the spread of a novel strategy across a wide range.

scholarly journals Autumn migration direction of juvenile willow warblers (Phylloscopus t. trochilus and P. t. acredula) and their hybrids by qPCR SNP genotyping

2020 ◽  
Author(s):  
Tianhao Zhao ◽  
Mihaela Ilieva ◽  
Keith Larson ◽  
Max Lundberg ◽  
Júlio M. Neto ◽  
...  
Keyword(s):  
Snp Genotyping ◽  
Chromosome 1 ◽  
Autumn Migration ◽  
Migration Routes ◽  
Background Rate ◽  
Western Africa ◽  
Migration Direction ◽  
Migration Research ◽  
Breeding Grounds ◽  
Combined Genotypes

Abstract Background: Geographic regions, where two close-related taxa with different migration routes come into contact, are known as migratory divides. Hybrids originating from migratory divides are hypothesized to migrate intermediately relative to the parental populations. However, to date and due to technical limitations, few studies testing this hypothesis in wild birds and these have been to hybrids that have completed the migration back to the breeding grounds. Here, we make use of the well-established migration routes of willow warblers ( Phylloscopus trochilus ), for which the subspecies trochilus and acredula have migration-associated genetic markers on chromosomes 1 and 5. This enabled us to analyses the geographic distribution of pure and hybrid genotypes among juvenile birds on their first migration. Methods: Blood and feather samples were collected from wintering birds in eastern and western Africa (n = 69), and from juveniles during autumn migration in Portugal (n = 33), Italy (n = 38) and Bulgaria (n = 32). Genotyping was carried out by qPCR SNP assays, one SNP on chromosome 1 (SNP 65) and one on chromosome 5 (SNP 285). Both these SNPs have alternative alleles that are highly fixed (allele frequency>97%) in each of the subspecies. Results: The observed combined genotypes of the two SNPs were associated with the known migration routes and wintering distributions of trochilus and acredula . We found hybrids (HH) among the juveniles in Italy (5/38) and in Portugal (2/33). The proportion of hybrids in Italy was significantly higher than expected from a background rate of hybrid genotypes (1.5%) in allopatric populations of trochilus and acredula . Conclusions: Our genetic approach to assign individuals to subspecies and hybrids allowed us to investigate migration direction in juvenile birds on their first migration, which should illustrate the innate migratory direction with less of a bias than studies restricted to successful migrants. The excess of hybrid in Italy, suggests that they employ an intermediate route relative to the parental populations. Our qPCR SNP genotyping method is efficient for processing large sample sizes, and therefore powerful in migration research of species with known population genetic structure.

Backpacking with the Saints

2015 ◽  
Author(s):  
Belden C. Lane
Keyword(s):  
American Southwest ◽  
Spiritual Practice ◽  
Spiritual Journey ◽  
Human Response ◽  
John Muir ◽  
Hildegard Of Bingen ◽  
Wide Range ◽  
Thich Nhat Hanh ◽  
In The Wild ◽  
John Of The Cross

Carrying only basic camping equipment and a collection of the world's great spiritual writings, Belden C. Lane embarks on solitary spiritual treks through the Ozarks and across the American Southwest. For companions, he has only such teachers as Rumi, John of the Cross, Hildegard of Bingen, Dag Hammarskjöld, and Thomas Merton, and as he walks, he engages their writings with the natural wonders he encounters--Bell Mountain Wilderness with Søren Kierkegaard, Moonshine Hollow with Thich Nhat Hanh--demonstrating how being alone in the wild opens a rare view onto one's interior landscape, and how the saints' writings reveal the divine in nature. The discipline of backpacking, Lane shows, is a metaphor for a spiritual journey. Just as the wilderness offered revelations to the early Desert Christians, backpacking hones crucial spiritual skills: paying attention, traveling light, practicing silence, and exercising wonder. Lane engages the practice not only with a wide range of spiritual writings--Celtic, Catholic, Protestant, Buddhist, Hindu, and Sufi Muslim--but with the fascination of other lovers of the backcountry, from John Muir and Ed Abbey to Bill Plotkin and Cheryl Strayed. In this intimate and down-to-earth narrative, backpacking is shown to be a spiritual practice that allows the discovery of God amidst the beauty and unexpected terrors of nature. Adoration, Lane suggests, is the most appropriate human response to what we cannot explain, but have nonetheless learned to love. An enchanting narrative for Christians of all denominations, Backpacking with the Saints is an inspiring exploration of how solitude, simplicity, and mindfulness are illuminated and encouraged by the discipline of backcountry wandering, and of how the wilderness itself becomes a way of knowing-an ecology of the soul.

scholarly journals A Productive Expression Platform Derived from Host-Restricted Eilat Virus: Its Extensive Validation and Novel Strategy

Viruses ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 660
Author(s):  
Lu Tan ◽  
Yiwen Zhang ◽  
Xingxing Wang ◽  
Dal Young Kim
Keyword(s):  
Expression Vectors ◽  
Structural Genes ◽  
Host Restriction ◽  
Expression Platform ◽  
Mosquito Cells ◽  
Wide Range ◽  
Restriction Property ◽  
Infected Cells ◽  
Multiple Levels ◽  
Novel Strategy

Most alphaviruses are transmitted by mosquitoes and infect a wide range of insects and vertebrates. However, Eilat virus (EILV) is defective for infecting vertebrate cells at multiple levels of the viral life cycle. This host-restriction property renders EILV an attractive expression platform since it is not infectious for vertebrates and therefore provides a highly advantageous safety profile. Here, we investigated the feasibility of versatile EILV-based expression vectors. By replacing the structural genes of EILV with those of other alphaviruses, we generated seven different chimeras. These chimeras were readily rescued in the original mosquito cells and were able to reach high titers, suggesting that EILV is capable of packaging the structural proteins of different lineages. We also explored the ability of EILV to express authentic antigens via double subgenomic (SG) RNA vectors. Four foreign genetic materials of varied length were introduced into the EILV genome, and the expressed heterologous genetic materials were readily detected in the infected cells. By inserting an additional SG promoter into the chimera genome containing the structural genes of Chikungunya virus (CHIKV), we developed a bivalent vaccine candidate against CHIKV and Zika virus. These data demonstrate the outstanding compatibility of the EILV genome. The produced recombinants can be applied to vaccine and diagnostic tool development, but more investigations are required.

Automated monitoring of a large-scale cod (Gadus morhua) migration in the open sea

2002 ◽  
Vol 59 (12) ◽  
pp. 1845-1850 ◽  
Author(s):  
Luc A Comeau ◽  
Steven E Campana ◽  
Martin Castonguay
Keyword(s):  
Large Scale ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Seasonal Migration ◽  
Migration Routes ◽  
Eastern Canada ◽  
Migration Patterns ◽  
Migration Timing ◽  
Open Sea ◽  
And Migration

The migration patterns of marine fishes are poorly known, in part owing to the technical limitations associated with tracking the movements of animals in deep water. Here we document a large-scale, directed, migration of Atlantic cod (Gadus morhua) off eastern Canada. Our approach was based on the acoustic tagging of 126 fish and the deployment of 69 subsurface receivers, stretching over a 160-km distance along the edge of the Laurentian Channel. After 1 year of automated recording, we found that 65% of the fish migrated out of coastal waters in two distinct runs during the summer–autumn period. The offshore-migrating fish overwintered in deep Laurentian Channel waters, returning inshore in April. Individual migration routes and migration timing were variable, indicating that the cod did not aggregate in large schools during the seasonal migration events.

scholarly journals Deciphering the evolution of microbial interactions: in silico studies of two-member microbial communities

2022 ◽  
Author(s):  
Gayathri Sambamoorthy ◽  
Karthik Raman
Keyword(s):  
Microbial Communities ◽  
In Silico ◽  
Microbial Interactions ◽  
Interaction Patterns ◽  
Wild Type ◽  
Community Function ◽  
Evolutionary Forces ◽  
In Silico Studies ◽  
Wide Range ◽  
In The Wild

Microbes thrive in communities, embedded in a complex web of interactions. These interactions, particularly metabolic interactions, play a crucial role in maintaining the community structure and function. As the organisms thrive and evolve, a variety of evolutionary processes alter the interactions among the organisms in the community, although the community function remains intact. In this work, we simulate the evolution of two-member microbial communities in silico to study how evolutionary forces can shape the interactions between organisms. We employ genomescale metabolic models of organisms from the human gut, which exhibit a range of interaction patterns, from mutualism to parasitism. We observe that the evolution of microbial interactions varies depending upon the starting interaction and also on the metabolic capabilities of the organisms in the community. We find that evolutionary constraints play a significant role in shaping the dependencies of organisms in the community. Evolution of microbial communities yields fitness benefits in only a small fraction of the communities, and is also dependent on the interaction type of the wild-type communities. The metabolites cross-fed in the wild-type communities appear in only less than 50% of the evolved communities. A wide range of new metabolites are cross-fed as the communities evolve. Further, the dynamics of microbial interactions are not specific to the interaction of the wild-type community but vary depending on the organisms present in the community. Our approach of evolving microbial communities in silico provides an exciting glimpse of the dynamics of microbial interactions and offers several avenues for future investigations.

‘Our Greatest Riches’: Horses at the Intersection of Settler and Kazakh Society in the Late Imperial Period

2017 ◽  
Vol 3 (2) ◽  
pp. 210-228
Author(s):  
Sean McDaniel
Keyword(s):  
Nineteenth Century ◽  
Land Use ◽  
Twentieth Century ◽  
Seasonal Migration ◽  
Late Nineteenth Century ◽  
Migration Routes ◽  
Late Imperial ◽  
Imperial Period ◽  
The Social ◽  
Late Nineteenth

This article examines interactions between Slavic peasant migrants and mobile pastoralist Kazakhs within the setting of the Kazakh Steppe during the period of heaviest resettlement to the region beginning in the late nineteenth century and continuing into the early twentieth century. It considers how the importance of horses to both settlers and Kazakhs alike dictated these interactions and how the sedentary world of the settlers disrupted the seasonal migration routes of Kazakh horse herders. Particularly with concern to the greatly expanded horse market, issues regarding land use, and increased instances of horse theft throughout the region, the Russian state’s encroachment into the steppe forever altered the social and economic makeup of the region.

scholarly journals Historical and current distribution, population size and possible migration routes of the Blue Swallow Hirundo atrocaerulea in Africa

2010 ◽  
Vol 20 (3) ◽  
pp. 240-254 ◽  
Author(s):  
STEVEN W. EVANS ◽  
H. BOUWMAN
Keyword(s):  
Population Size ◽  
Democratic Republic ◽  
Sub Saharan Africa ◽  
Total Current ◽  
Migration Routes ◽  
Breeding Grounds ◽  
Republic Of The Congo ◽  
Migratory Routes ◽  
Sub Saharan ◽  
And Migration

SummaryThe Blue Swallow Hirundo atrocaerulea is restricted to sub-Saharan Africa, its population size previously estimated at fewer than 1,500 pairs, and is classified as Vulnerable. A better understanding of its current distributional range, population size, protection status and migration routes would improve our ability to conserve the species and the grassland and wetland habitat on which it depends. We now estimate that the Blue Swallow population in the 1850s may have numbered between 1,560 and 2,300 pairs. Based on an assessment of available data, we now estimate the total current Blue Swallow population at 1,006 pairs or 2,012 individuals, an estimated 36–56% decline over the last 150 years. There may be three separate Blue Swallow sub-populations and seven separate migratory routes between their breeding and non-breeding grounds. The Blue Swallow’s range in South Africa and Swaziland has contracted by 74%. The majority of Blue Swallows occupy unprotected areas on their non-breeding grounds in the Democratic Republic of the Congo, Uganda and Kenya. The Blue Swallow population in Africa will continue to decline unless the causes of reduction in Blue Swallow habitat quantity and quality can be stopped and sufficient and additional habitat set aside to sustain viable Blue Swallow populations throughout their range.

scholarly journals Vision and touch in relation to foraging and predator detection: insightful contrasts between a plover and a sandpiper

2008 ◽  
Vol 276 (1656) ◽  
pp. 437-445 ◽  
Author(s):  
Graham R Martin ◽  
Theunis Piersma
Keyword(s):  
Visual Fields ◽  
Skeletal Structure ◽  
Visually Guided ◽  
Sources Of Information ◽  
Predator Detection ◽  
Food Items ◽  
Binocular Field ◽  
Blind Area ◽  
Wide Range ◽  
Breeding Grounds

Visual fields were determined in two species of shorebirds (Charadriiformes) whose foraging is guided primarily by different sources of information: red knots ( Calidris canutus , tactile foragers) and European golden plovers ( Pluvialis apricaria , visual foragers). The visual fields of both species showed features that are found in a wide range of birds whose foraging involves precision pecking or lunging at food items. Surprisingly, red knots did not show comprehensive panoramic vision as found in some other tactile feeders; they have a binocular field surrounding the bill and a substantial blind area behind the head. We argue that this is because knots switch to more visually guided foraging on their breeding grounds. However, this visual field topography leaves them vulnerable to predation, especially when using tactile foraging in non-breeding locations where predation by falcons is an important selection factor. Golden plovers use visually guided foraging throughout the year, and so it is not surprising that they have precision-pecking frontal visual fields. However, they often feed at night and this is associated with relatively large eyes. These are anchored in the skull by a wing of bone extending from the dorsal perimeter of each orbit; a skeletal structure previously unreported in birds and which we have named ‘supraorbital aliform bone’, Os supraorbitale aliforme . The larger eyes and their associated supraorbital wings result in a wide blind area above the head, which may leave these plovers particularly vulnerable to predation. Thus, in these two shorebirds, we see clear examples of the trade-off between the two key functions of visual fields: (i) the detection of predators remote from the animal and (ii) the control of accurate behaviours, such as the procurement of food items, at close quarters.

Inheritance of Acetyl-CoA Carboxylase Inhibitor Resistance in Wild Oat (Avena fatua)

Weed Science ◽  
1995 ◽  
Vol 43 (2) ◽  
pp. 233-238 ◽  
Author(s):  
Bruce G. Murray ◽  
Ian N. Morrison ◽  
Anita L. Brûlé-Babel
Keyword(s):  
Nuclear Gene ◽  
Avena Fatua ◽  
Wild Oat ◽  
Acetyl Coa Carboxylase ◽  
Reciprocal Crosses ◽  
Characteristic Response ◽  
Wide Range ◽  
Segregation Ratios ◽  
In The Wild ◽  
Inhibitor Resistance

Resistance to fenoxaprop-P and other aryloxyphenoxypropionate and cyclohexanedione herbicides in the wild oat population, UM1, is controlled by a single, partially dominant, nuclear gene. In arriving at this conclusion, parents, F1hybrids, and F2plants derived from reciprocal crosses between UM1 and a susceptible wild oat line, UM5, were treated with fenoxaprop-P over a wide range of dosages. Based on these experiments, a dosage of 400 g ai ha−1fenoxaprop-P was selected to discriminate between three response types. At this dosage, susceptible plants were killed and resistant plants were unaffected, whereas plants characterized as intermediate in response were injured but recovered. Treated F2plants segregated in a 1:2:1 (R, I, S) ratio, indicative of single nuclear gene inheritance. This was confirmed by selfing F2plants and screening several F3families. Families derived from intermediate F2plants segregated for the three characteristic response types, whereas those derived from resistant F2plants were uniformly resistant. Chisquare analysis indicated the F2segregation ratios fit those expected for a single partially dominant nuclear gene system. In addition, F2populations from both crosses were screened with a mixture of fenoxaprop-Pand sethoxydim. The dosages of both herbicides (150 g ai ha−1fenoxaprop-P and 100 g ha−1sethoxydim) were sufficient to control only susceptible plants. Treated F2populations segregated in a 3:1 (R:S) pattern, thereby confirming that resistance to the two chemically unrelated herbicides results from the same gene alteration.

scholarly journals Discovery of breeding grounds of a Siberian Crane Grus leucogeranus flock that winters in Iran, via satellite telemetry

2002 ◽  
Vol 12 (4) ◽  
pp. 327-333 ◽  
Author(s):  
Yutaka Kanai ◽  
Meenakshi Nagendran ◽  
Mutsuyuki Ueta ◽  
Yuri Markin ◽  
Juhani Rinne ◽  
...  
Keyword(s):  
Satellite Telemetry ◽  
Migration Routes ◽  
Breeding Area ◽  
Volga River ◽  
Western Population ◽  
Siberian Crane ◽  
Grus Leucogeranus ◽  
Volga River Delta ◽  
Breeding Grounds ◽  
Conservation Plan

Siberian Crane Grus leucogeranus occurs only in Asia, and is Critically Endangered. The western population of the species has been almost extirpated, wintering at just two known sites, in Iran and India. To help conserve species that migrate long distances it is essential to have a comprehensive conservation plan that includes identification of migration routes and key resting areas. One Siberian Crane was satellite-tracked from the south Caspian Sea to its breeding grounds in Russia during the spring of 1996. The crane began migration on 6 March, and completed its migration on 1 May. This destination was formerly unknown as a breeding area for the species. During migration, the crane rested primarily at the eastern end of the Volga River delta. This suggests that the delta may be an important resting site for Siberian Crane.

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