Sökning: "Sexual signals"

Visar resultat 1 - 5 av 23 avhandlingar innehållade orden Sexual signals.

1. 1. Sexual Signals and Speciation : A Study of the Pied and Collared Flycatcher

   Författare :Jon Haavie; Glenn-Peter Saetre; Trevor Price; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; Speciation; Sexual signals; Hybridization; Reinforcement; Song; Female preference; Sex-linkage; Biologi; Biology; Biologi;

   Sammanfattning : Speciation is the process in which reproductive barriers evolve between populations. In this thesis I examine how sexual signals contribute to the maintenance, reinforcement or breakdown of reproductive barriers.Male pied flycatchers (Ficedula hypoleuca) and collared flycatchers (F. albicollis) differ in song and plumage traits. LÄS MER

3. 2. Natural and Sexual Selection in a Natural Hybrid Zone of Ficedula Flycatchers

   Författare :Nina Svedin; Anna Qvarnström; Lars Gustafsson; Ian Owens; Uppsala universitet; []
   Nyckelord :Biology; postzygotic isolation; prezygotic isolation; asymmetrical isolation; sexual signals; hybrid fitness; co-existence; Biologi;

   Sammanfattning : Speciation can be viewed as the formation of reproductive barriers between different populations. This thesis investigates patterns of natural and sexual selection shaping reproductive barriers between two hybridizing flycatchers (i.e. collared – and pied flycatchers). LÄS MER

4. 3. Polyandry and the evolution of reproductive divergence in insects

   Författare :Tina Nilsson; Göran Arnqvist; David Hosken; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Bruchidae; cryptic female choice; multiple mating; sexual conflict; sexually antagonistic coevolution; sexual selection; speciation; sperm competition; Tenebrionidae; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

   Sammanfattning : Multiple mating by females is common in nature. Yet, the evolution and maintenance of polyandry remains a bit of an evolutionary puzzle. It was my aim in this thesis to reach a greater understanding of this phenomenon as well as to investigate the consequences of polyandry on the evolution of reproductive divergence in insects. LÄS MER

5. 4. Sex and violence in lobsters - a smelly business

   Författare :Malin Skog; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; dominance; urine signals; recognition; Aggressive behaviours; intermoult mating; sexual dimorphism; European lobster; chemical communication; Homarus gammarus; aesthetasc morphology;

   Sammanfattning : The aim of this thesis was to study the chemical communication involved in aggressive and reproductive behaviours in the European lobster (Homarus gammarus). Both male and female H. gammarus established and maintained dominance, but the sexes used different strategies for dominance maintenance. LÄS MER

7. 5. Fishing for Females : Sensory Exploitation in the Swordtail Characin

   Författare :Mirjam Amcoff; Niclas Kolm; Michael Ryan; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Sexual selection; Mate choice; Courtship; Sensory bias; Plasticity; Corynopoma riisei; Mulitiple signalling; Biologi med inriktning mot zooekologi; Biology with specialization in Animal Ecology;

   Sammanfattning : Mate choice plays an important role in sexual selection and speciation. The evolution of mate choice is intriguing in cases where choosy individuals gain little except for genetic material from the mate and where the trait used as a criterion for the choice is costly to its bearer. LÄS MER