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Corticosterone's roles in avian migration: Assessment of three hypotheses
Hormones and Behavior, 2021While corticosterone (CORT) is often suggested to be an important hormone regulating processes necessary for avian migration, there has been no systematic assessment of CORT's role in migration. Prior to migration, birds increase fat stores and flight muscle size to prepare for the high energetic costs associated with long-distance flight.
Bauer, Carolyn M., Watts, H. E.
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Development and migration of avian sympathetic preganglionic neurons
Journal of Comparative Neurology, 1991AbstractModern neuronanatomical techniques were used to investigate the development of the avian sympathetic preganglionic cell column in the spinal cord of the chick embryo. [3H]thymidine autoradiography indicated that the majority of these preganglionic, or “Terni column” neurons are generated between stages 18 and 24 (days 2–4).
A, Prasad, M, Hollyday
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2000
Abstract The migration of birds is a complex form of behavior, affected by many environmental factors, such as spatial and temporal variations in food availability, predators, temperature, winds, and breeding opportunities (Ens et al. 1994).
Colin W Clark, Marc Mangel
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Abstract The migration of birds is a complex form of behavior, affected by many environmental factors, such as spatial and temporal variations in food availability, predators, temperature, winds, and breeding opportunities (Ens et al. 1994).
Colin W Clark, Marc Mangel
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Circadian and Circannual Programmes in Avian Migration
Journal of Experimental Biology, 1996ABSTRACT In migratory birds, endogenous daily (circadian) and annual (circannual) rhythms serve as biological clocks that provide the major basis for their temporal orientation. Circannual rhythms are responsible for the initiation of migration both in autumn and spring.
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Atmospheric Structure and Avian Migration
1989Why do some birds migrate during daytime and others at night? Why do some fly at high altitudes and others at lower altitudes? Whereas no comprehensive explanation of the diel schedule and altitude of migration has been proposed, several hypotheses have been advanced to explain nocturnal migration.
Paul Kerlinger, Frank R. Moore
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Circannual and Circadian Contributions to the Timing of Avian Migration
2003Only a few phenomena in the living world occur as predictably with regard to both time of day and time of year as the migrations of birds. Humans living along the major migratory pathways have exploited for ages the opportunity of enriching their diet with valuable animal protein provided by migrant birds. Because the times of passage are exactly known,
Gwinner, E., Helm, B.
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Migrating myoelectric complex demonstrated in four avian species
American Journal of Physiology-Gastrointestinal and Liver Physiology, 1989The migrating myoelectric complex (MMC) is demonstrated in four avian species: three gallinaceous birds (Gallus, Phasianus, Coturnix) and an owl (Strix). The complex in birds is strikingly similar to the MMC that is known in mammalian species. It has the same basic pattern of quiescence, followed by a period of irregular spike activity, then a period ...
M H, Clench +2 more
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Circannual clocks in avian reproduction and migration
Ibis, 1996Many behavioural and physiological functions of organisms are adjusted to the periodic changes in their environment, particularly to those related to the natural day and year. This adjustment is often achieved through the action of endogenous daily (circadian) and annual (circannual) clocks.
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Circannual Rhythms in the Control of Avian Migrations
1986Publisher Summary The chapter discusses some functional aspects of circannual rhythms in migratory birds and summarizes the results that have accumulated over the past few years, indicating a fundamental involvement of endogenous circannual programs in the control of various aspects of migratory behavior, particularly in long-distance migrants ...
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