Sökning: "parental investment"

Visar resultat 11 - 15 av 29 avhandlingar innehållade orden parental investment.

1. 11. Influence of Mate Quality on Reproductive Decisions in a Fish with Paternal Care

   Författare :Niclas Kolm; Anders Berglund; Ben Sheldon; Kai Lindström; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; sexual selection; differential allocation; evolution of egg size and parental care; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

   Sammanfattning : Female reproductive decisions have been suggested to be highly influenced by mate quality. I have studied whether offspring quality may be adjusted by females to match the attractiveness of males and how strong control females have over their reproductive investment focusing on egg size. LÄS MER

3. 12. Sexual selection in the collared flycatcher (Ficedula albicollis) : A life-history perspective

   Författare :Anna Qvarnström; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Sexual selection; life-history; honest signalling; fighting ability; genotype-environment interaction; direct benefits; indirect benefits; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

   Sammanfattning : This thesis integrates sexual selection theory with life history theory to elucidate the causes and consequences of variation in a male secondary sexual trait. The model organism, the collared flycatcher (Ficedula albicollis), was studied on Gotland, Sweden. LÄS MER

4. 13. Nesting and migration in the introduced Canada goose in Sweden

   Författare :Göran Sjöberg; Catherine M. Lessells; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Species introductions; DNA fingerprinting; natal dispersal; breeding dispersal; bird migration; wintering areas; clutch size; laying date; body reserves; nest defence; waterfowl; Canada goose; Anatidae; Branta canadensis;

   Sammanfattning : The aim of the thesis was to document patterns in breeding and migration in Swedish Canada geese Branta canadensis, to explain these against the genetic and historical background of the population, and to test predictions of hypotheses pertaining to parental investment.The Canada goose population in Sweden was founded by the introduction of a few individuals in the 1930's. LÄS MER

5. 14. Female choice and paternal care in the fifteen-spined stickleback, Spinachia spinachia

   Författare :Sara Östlund-Nilsson; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; fifteen-spined stickleback; spinachia spinachia; female choice; paternal care; nest building; ornament; fanning; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; Animal Ecology; zooekologi;

   Sammanfattning : In the fifteen-spined stickleback, Spinachia spinachia, males provide females with direct benefits by fanning, cleaning and guarding the offspring. Males announce their parental skills through intense body shakes during courtship. Females preferred to mate with more intensely shaking males. LÄS MER

7. 15. Condition-dependence in life history evolution

   Författare :Foteini Spagopoulou; Alexei Maklakov; Lars Gustafsson; Russell Bonduriansky; Pat Monaghan; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ageing; senescence; nongenetic inheritance; sex differences; condition-dependence; life history; trade-off; Ficedula albicollis; Caenorhabditis remanei; Telostylinus angusticollis; Biologi med inriktning mot zooekologi; Biology with specialization in Animal Ecology;

   Sammanfattning : Ageing is the progressive physiological deterioration that appears with increasing age and eventually leads to a decline in survival and reproduction. This physiological process is omnipresent across the tree of life, but the expected trajectory can widely vary between and within species. LÄS MER