Sökning: "breeding biology"
Visar resultat 1 - 5 av 95 avhandlingar innehållade orden breeding biology.
1. Hybrid zone dynamics, assortative mating, and migratory programmes in a willow warbler migratory divide
Sammanfattning : In this thesis I will compare and contrast the two willow warbler subspecies (Phylloscopus trochilus trochilus and P. t. acredula) with differing migratory phenotypes (or "migratype") in the context of their migratory divide and hybrid zone in central Sweden. Their migratory programs differ in the direction and distance traveled during migration. LÄS MER
2. Domestication Effects on the Stress Response in Chickens : Genetics, Physiology, and Behaviour
Sammanfattning : Animal domestication, the process where animals become adapted to living in proximity to humans, is associated with the alteration of multiple traits, including decreased fearfulness and stress response. With an estimated population of 50 billion, the domesticated chicken is the most populous avian species in the world. LÄS MER
3. Female coloration, egg carotenoids and reproductive success: gobies as a model system
Sammanfattning : In two-spotted gobies (Gobiusculus flavescens), females develop an orange belly as they approach sexual maturity. Toward the end of the single breeding season, males become rare and females compete for spawnings. Nest-holding males then prefer females with more colourful bellies and this trait has been suggested to act as a female ornament. LÄS MER
4. Cooperative Breeding in the Southern Anteater-Chat : Sexual Disparity, Survival and Dispersal
Sammanfattning : Group-living sets the scene for complex social behaviours such as cooperative breeding, and exploring the factors that shape group-living is crucial in understanding these behaviours. This thesis explores the ecology of a population of the facultative cooperative breeding southern anteater-chat (Myrmecocichla formicivora), a group-living bird species endemic to southern Africa. LÄS MER
5. Sperm Membrane Channels, Receptors and Kinematics : Using boar spermatozoa for drug toxicity screening
Sammanfattning : Internal fertilization usually implies that a spermatozoon, with intact attributes for zygote formation, passes all hurdles during its transport through the female genitalia and reaches the oocyte. During this journey, millions to billions of other spermatozoa perish. LÄS MER