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A General Model for Time-minimising Avian Migration
Journal of Theoretical Biology, 1997Abstract We develop an optimality model for time-minimising bird migration for any distribution of feeding habitats and qualities along the migratory route. If the fuel deposition rate is constant along the route and feeding is possible everywhere, it is optimal to divide the journey into steps of equal length.
Weber, TP, Houston, AI
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Hemopoietic Cell Progenitors in the Avian Embryo: Origin and Migrations
Annals of the New York Academy of Sciences, 1987The cellular events involved in the formation of hemopoietic progenitors during early embryogenesis are critical for the lifelong function of the blood‐forming system if, as is supposed, these progenitors arise during ontogeny and thereafter maintain their stock by self renewal.
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On the migration of epidermal melanoblasts in the avian embryonic wing bud
Anatomy and Embryology, 1984After heterotopic grafting of quail neural crest cells to the wing buds of embryos of an unpigmented chicken strain, epidermal melanocytes of donor origin are found almost exclusively distal from the graft in the host's epidermis. This directed cell migration ceases, if the apical ectodermal ridge (together with a small amount of subridge mesoderm) is ...
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On the Differentiation and Migration of the Wolffian Duct in Avian Embryos
1992It has long been believed that the Wolffian (pro- or mesonephric) duct is formed by the fusion of the pronephric tubules, although Gasser (1877) had described its origin from an unsegmented ridge at the dorsal side of the intermediate mesoderm. This observation was confirmed by Torrey (1954) on human embryos, and finally, by SEM investigations (Jacob ...
Monika Jacob +2 more
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Spatiotemporal aspects of avian long-distance migration
1998Abstract Far-reaching migratory movements define the birds as the most mobile group of animals, whose network of migration routes cover most of the earth’s surface. Most conspicuous are the long-distance intercontinental and transoceanic migratory movements.
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Avian Migration: Regulation of Facultative-Type Movements
2003Virtually all environments vary in space and time. Therefore, individuals should express a phenotype, within the population reaction norm, that is best suited for the conditions it encounters (Via and Lande 1985; Kawecki and Stearns 1993). However, because most environments change markedly with season, many individuals actually move from one ...
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