Measures of oxidative state are primarily driven by extrinsic factors in a long-distance migrant

Oxidative stress is a likely consequence of hard physical exertion and thus a potential mediator of life-history trade-offs in migratory animals. However, little is known about the relative importance of intrinsic and extrinsic stressors on the oxidative state of individuals in wild populations. We quantified the relationships between air temperature, sex, body condition and three markers of oxidative state (malondialdehyde, superoxide dismutase and total antioxidant capacity) across hundreds of individuals of a long-distance migrant (the brent goose Branta bernicla hrota ) during wintering and spring staging. We found that air temperature and migratory stage were the strongest predictors of oxidative state. This emphasizes the importance of extrinsic factors in regulating the oxidative state of migrating birds, with differential effects across the migration. The significance of abiotic effects demonstrates an additional mechanism by which changing climates may affect migratory costs.

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Evaluation of Long-Distance Orientation in Birds on the Basis of Migration Routes Recorded by Radar and Satellite Tracking

Journal of Navigation ◽

10.1017/s0373463301001400 ◽

2001 ◽

Vol 54 (3) ◽

pp. 393-403 ◽

Cited By ~ 6

Author(s):

Thomas Alerstam

Keyword(s):

Large Scale ◽

Satellite Tracking ◽

Polar Regions ◽

High Latitudes ◽

Migration Routes ◽

Long Distance ◽

Sun Compass ◽

Branta Bernicla ◽

Migrating Birds ◽

East West

Predicted flight trajectories differ depending on which orientation cues are used by migrating birds. Results from radar and satellite tracking of migrating birds can be used to test which of the predicted trajectories shows the best fit with observed flight routes, supporting the use of the associated orientation mechanism. Radar studies of bird migration at the Northeast Passage and the Northwest Passage support the occurrence of migration along sun compass routes in these polar regions. In contrast, satellite tracking of Brent geese (Branta bernicla) migrating from Iceland across Greenland and from Northwest Europe to Siberia show routes that conform most closely with geographic loxodromes, but which are also profoundly influenced by large-scale topography. These evaluations are discussed in relation to the adaptive values of different routes in different parts of the world. Sun compass routes are favourable mainly for east-west migration at high latitudes. For east-west migration at mid and high latitudes magnetic loxodromes are more favourable than geographic loxodromes in certain regions while the reverse holds in other regions. The geometry of migration routes, as recorded by radar and satellite tracking, may be important for understanding the evolution of the complexity of birds' orientation systems, and for providing clues about the orientation mechanisms guiding the birds on their global journeys.

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Insights into antimicrobial resistance among long distance migratory East Canadian High Arctic light-bellied Brent geese (Branta bernicla hrota)

Irish Veterinary Journal ◽

10.1186/s13620-016-0072-7 ◽

2015 ◽

Vol 69 (1) ◽

Cited By ~ 8

Author(s):

Austin Agnew ◽

Juan Wang ◽

Séamus Fanning ◽

Stuart Bearhop ◽

Barry J. McMahon

Keyword(s):

Antimicrobial Resistance ◽

High Arctic ◽

Canadian High Arctic ◽

Long Distance ◽

Branta Bernicla ◽

Branta Bernicla Hrota

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Habitat utilisation during staging affects body condition in a long distance migrant,Branta bernicla hrota: potential impacts on fitness?

Journal of Avian Biology ◽

10.1111/j.1600-048x.2008.04332.x ◽

2008 ◽

Vol 39 (6) ◽

pp. 704-708 ◽

Cited By ~ 22

Author(s):

R. Inger ◽

G. A. Gudmundsson ◽

G. D. Ruxton ◽

J. Newton ◽

K. Colhoun ◽

...

Keyword(s):

Body Condition ◽

Long Distance ◽

Branta Bernicla ◽

Branta Bernicla Hrota

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From tree to architecture: how functional morphology of arborescence connects plant biology, evolution and physics

Palaeobiodiversity and Palaeoenvironments ◽

10.1007/s12549-020-00466-9 ◽

2021 ◽

Author(s):

Anita Roth-Nebelsick ◽

Tatiana Miranda ◽

Martin Ebner ◽

Wilfried Konrad ◽

Christopher Traiser

Keyword(s):

Land Plant ◽

Plant Evolution ◽

Ecological Niches ◽

Long Distance ◽

Ongoing Research ◽

Long Distance Transport ◽

Theoretical Approaches ◽

Trade Offs ◽

Interfacial Physics ◽

Plant Water Transport

AbstractTrees are the fundamental element of forest ecosystems, made possible by their mechanical qualities and their highly sophisticated conductive tissues. The evolution of trees, and thereby the evolution of forests, were ecologically transformative and affected climate and biogeochemical cycles fundamentally. Trees also offer a substantial amount of ecological niches for other organisms, such as epiphytes, creating a vast amount of habitats. During land plant evolution, a variety of different tree constructions evolved and their constructional principles are a subject of ongoing research. Understanding the “natural construction” of trees benefits strongly from methods and approaches from physics and engineering. Plant water transport is a good example for the ongoing demand for interdisciplinary efforts to unravel form-function relationships on vastly differing scales. Identification of the unique mechanism of water long-distance transport requires a solid basis of interfacial physics and thermodynamics. Studying tree functions by using theoretical approaches is, however, not a one-sided affair: The complex interrelationships between traits, functionality, trade-offs and phylogeny inspire engineers, physicists and architects until today.

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Limited Access to Food and Physiological Trade‐Offs in a Long‐Distance Migrant Shorebird. I. Energy Metabolism, Behavior, and Body‐Mass Regulation

Physiological and Biochemical Zoology ◽

10.1086/603644 ◽

2009 ◽

Vol 82 (5) ◽

pp. 549-560 ◽

Cited By ~ 8

Author(s):

François Vézina ◽

Magali Petit ◽

Deborah M. Buehler ◽

Anne Dekinga ◽

Theunis Piersma

Keyword(s):

Energy Metabolism ◽

Body Mass ◽

Long Distance ◽

Limited Access ◽

Body Mass Regulation ◽

Trade Offs ◽

Access To Food

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Limited Access to Food and Physiological Trade‐Offs in a Long‐Distance Migrant Shorebird. II. Constitutive Immune Function and the Acute‐Phase Response

Physiological and Biochemical Zoology ◽

10.1086/603635 ◽

2009 ◽

Vol 82 (5) ◽

pp. 561-571 ◽

Cited By ~ 41

Author(s):

Deborah M. Buehler ◽

Francisco Encinas‐Viso ◽

Magali Petit ◽

François Vézina ◽

B. Irene Tieleman ◽

...

Keyword(s):

Immune Function ◽

Acute Phase ◽

Acute Phase Response ◽

Phase Response ◽

Long Distance ◽

Limited Access ◽

Trade Offs ◽

Access To Food

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Long-period changes of the air temperature in Tatarstan and their forecast till the end of the 21st century

Journal of the Belarusian State University. Geography and Geology ◽

10.33581/2521-6740-2019-2-94-107 ◽

2019 ◽

pp. 94-107

Author(s):

Yuri P. Perevedentsev ◽

Konstantin M. Shantalinskii ◽

Boris G. Sherstukov ◽

Alexander A. Nikolaev

Keyword(s):

Surface Temperature ◽

Air Temperature ◽

21St Century ◽

Ocean Surface ◽

The Arctic ◽

Long Distance ◽

Climate Fluctuations ◽

Long Period ◽

The Earth

Long-term changes in air temperature on the territory of the Republic of Tatarstan in the 20th–21st centuries are considered. The periods of unambiguous changes in the surface air temperature are determined. It is established that the average winter temperature from the 1970s to 2017, increased in the Kazan region by more than 3 °C and the average summer temperature increased by about 2 °C over the same period. The contribution of global scale processes to the variability of the temperature of the Kazan region is shown: it was 37 % in winter, 23 % in summer. The correlation analysis of the anomalies of average annual air temperature in Kazan and the series of air temperature anomalies in each node over the continents, as well as the ocean surface temperature in each coordinate node on Earth for 1880 –2017, was performed. Long-distance communications were detected in the temperature field between Kazan and remote regions of the Earth. It is noted that long-period climate fluctuations in Kazan occur synchronously with fluctuations in the high latitudes of Asia and North America, with fluctuations in ocean surface temperature in the Arctic ocean, with fluctuations in air temperature in the Far East, and with fluctuations in ocean surface temperature in the Southern hemisphere in the Indian and Pacific oceans, as well as air temperature in southern Australia. It is suggested that there is a global mechanism that regulates long-term climate fluctuations throughout the Earth in the considered interval of 200 years of observations. According to the CMIP5 project, climatic scenarios were built for Kazan until the end of the 21st century.

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Memories of Migrations Past: Sociality and Cognition in Dynamic, Seasonal Environments

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.742920 ◽

2021 ◽

Vol 9 ◽

Author(s):

Eliezer Gurarie ◽

Sriya Potluri ◽

George Christopher Cosner ◽

Robert Stephen Cantrell ◽

William F. Fagan

Keyword(s):

Environmental Changes ◽

Animal Movement ◽

Spatial Scales ◽

Rapid Change ◽

Reference Memory ◽

Migratory Behavior ◽

Migration Behavior ◽

Long Distance ◽

Trade Offs ◽

Resource Dynamics

Seasonal migrations are a widespread and broadly successful strategy for animals to exploit periodic and localized resources over large spatial scales. It remains an open and largely case-specific question whether long-distance migrations are resilient to environmental disruptions. High levels of mobility suggest an ability to shift ranges that can confer resilience. On the other hand, a conservative, hard-wired commitment to a risky behavior can be costly if conditions change. Mechanisms that contribute to migration include identification and responsiveness to resources, sociality, and cognitive processes such as spatial memory and learning. Our goal was to explore the extent to which these factors interact not only to maintain a migratory behavior but also to provide resilience against environmental changes. We develop a diffusion-advection model of animal movement in which an endogenous migratory behavior is modified by recent experiences via a memory process, and animals have a social swarming-like behavior over a range of spatial scales. We found that this relatively simple framework was able to adapt to a stable, seasonal resource dynamic under a broad range of parameter values. Furthermore, the model was able to acquire an adaptive migration behavior with time. However, the resilience of the process depended on all the parameters under consideration, with many complex trade-offs. For example, the spatial scale of sociality needed to be large enough to capture changes in the resource, but not so large that the acquired collective information was overly diluted. A long-term reference memory was important for hedging against a highly stochastic process, but a higher weighting of more recent memory was needed for adapting to directional changes in resource phenology. Our model provides a general and versatile framework for exploring the interaction of memory, movement, social and resource dynamics, even as environmental conditions globally are undergoing rapid change.

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rab-27 acts in an intestinal pathway to inhibit axon regeneration in C. elegans

PLoS Genetics ◽

10.1371/journal.pgen.1009877 ◽

2021 ◽

Vol 17 (11) ◽

pp. e1009877

Author(s):

Alexander T. Lin-Moore ◽

Motunrayo J. Oyeyemi ◽

Marc Hammarlund

Keyword(s):

Motor Neurons ◽

Axon Regeneration ◽

Rab Gtpase ◽

Long Distance ◽

Extrinsic Factors ◽

C Elegans ◽

Cellular Environment ◽

Neuropeptide Secretion ◽

Neuronal Tissues ◽

Nervous System Function

Injured axons must regenerate to restore nervous system function, and regeneration is regulated in part by external factors from non-neuronal tissues. Many of these extrinsic factors act in the immediate cellular environment of the axon to promote or restrict regeneration, but the existence of long-distance signals regulating axon regeneration has not been clear. Here we show that the Rab GTPase rab-27 inhibits regeneration of GABAergic motor neurons in C. elegans through activity in the intestine. Re-expression of RAB-27, but not the closely related RAB-3, in the intestine of rab-27 mutant animals is sufficient to rescue normal regeneration. Several additional components of an intestinal neuropeptide secretion pathway also inhibit axon regeneration, including NPDC1/cab-1, SNAP25/aex-4, KPC3/aex-5, and the neuropeptide NLP-40, and re-expression of these genes in the intestine of mutant animals is sufficient to restore normal regeneration success. Additionally, NPDC1/cab-1 and SNAP25/aex-4 genetically interact with rab-27 in the context of axon regeneration inhibition. Together these data indicate that RAB-27-dependent neuropeptide secretion from the intestine inhibits axon regeneration, and point to distal tissues as potent extrinsic regulators of regeneration.

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