Sökning: "bird-migration"
Visar resultat 1 - 5 av 23 avhandlingar innehållade ordet bird-migration.
1. Individual consistency in bird migration
Sammanfattning : Slight differences, which appear in the individual animals of the same species and population have been recognised and appreciated ever since Darwin. These consistent intra-specific differences in animals have been considered very important because they are often inherited, and thus, provide the basic material for evolution to act on. LÄS MER
2. Time and energy in long-distance bird migration
Sammanfattning : Long-distance seasonal migration is energetically demanding and time consuming. For example, some passerine birds are on migration during six months of the year, travel more than 10 000 km and make use of many fuelling sites. Migration requires many different decisions, and an individual bird will face a variety of situations. LÄS MER
3. Statistical Methods for Taxon Classification and Bird Migration Phenology
Sammanfattning : The connection between ecology and statistics is deep. Methodological advancement in statistics open up new possibilities to understand the distribution of life on earth, and research questions in ecology cause new statistical methods to be developed. LÄS MER
4. On the role of migration for the distribution of arctic birds - a circumpolar perspective
Sammanfattning : Flexibility as well as constraints to the evolution of migration routes has the possibility of affecting large-scale patterns of geographical ranges of animals both by facilitating, but sometimes restricting, accessibility to and colonization of new regions. This dissertation concerns the broad-scale effects migration has on the distributional patterns of birds in the Arctic. LÄS MER
5. Migratory behavior and its genetic basis in willow warblers Phylloscopus trochilus
Sammanfattning : Right before northern hemisphere’s summer shifts to autumn small insect-eatingbirds start lengthy journeys to tropical regions. It is well established that temporarylack food and annual changes in weather are the ultimate reasons for this behavior.On a proximal level however, the process is poorly understood. LÄS MER