Sökning: "parental investment"

Visar resultat 1 - 5 av 29 avhandlingar innehållade orden parental investment.

  1. 1. Female reproductive strategies and sexual conflicts in a polygynous mating system

    Författare :Maria Sandell; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; female aggression; nestling feeding; intraspecific brood parasitism; mating system; parental investment; sexual conflict; intrasexual competition; Animal ecology; Djurekologi;

    Sammanfattning : In this thesis, I have investigated conflicts of interest in the facultatively polygynous European starling (Sturnus vulgaris) with a focus on female reproductive strategies. The extent to which males provided parental care was a key issue in understanding the mating system of the starling. LÄS MER

  3. 2. Paternal care and brood reduction in a pipefish

    Författare :Gry Sagebakken; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Parental care; brood reduction; embryo survival; parental condition; filial cannibalism; post-mating sexual selection; HSI; sexual conflicts; Syngnathus typhle; male brooding;

    Sammanfattning : From an evolutionary and adaptive perspective, the occurrence and extent of parental care in animals (investment in offspring beyond the genetic contribution) is expected to depend on an optimal (fitness-maximizing) balance of its costs and benefits. Males of the sex-role reversed broad-nosed pipefish, Syngnathus typhle, which care for eggs and embryos and may perform brood reduction, are particularly interesting in this respect. LÄS MER

  4. 3. Mutual Mate Choice in the Deep Snouted Pipefish Syngnathus typhle

    Författare :Maria Widemo; John D. Reynolds; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; Sexual selection; mutual mate choice; mate competition; sex role reversal; parental investment; Biologi; Biology; Biologi; Animal Ecology; zooekologi;

    Sammanfattning : This thesis integrates the fields of sexual selection, parental investment and sex role theory by investigating mutual mate choice and mate competition in the sex role reversed deep snouted pipefish Syngnathus typhle (Pisces: Syngnathidae) through a series of laboratory experiments. In S. LÄS MER

  5. 4. Egg size evolution and paternal care in pipefishes

    Författare :Inês Braga Gonçalves; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Egg size; embryo development; embryo survival; hypoxia; male quality; mate choice; mating constraints; oxygen; parental care; parental effects; paternal care; reproductive compensation; sex-role reversal; sexual conflict; Syngnathidae; Syngnathus typhle;

    Sammanfattning : In this thesis I explore how sexual selection, sexual conflicts, coevolution with parental care and an environmental selective agent (hypoxia) affect the evolution of different egg characteristics and embryo survival and size in pipefishes (Syngnathidae). In the broad-nosed pipefish, Syngnathus typhle Linnaeus, both sexes prefer to mate with large partners; large females produce more and larger eggs and large males can care for more young, and, as shown in this thesis, invest more per embryo and provide better oxygenation during brooding. LÄS MER

  7. 5. Reproductive investment in Syngnathus typhle, the broad-nosed pipefish

    Författare :Ines Goncalves; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Syngnathidae; sex-role reversal; paternal care; male quality; female choice; maternal effects; reproductive compensation; embryo development; brood reduction.;

    Sammanfattning : Manuscripts: 1 - Reproductive compensation by broad-nosed pipefish females. 2 - Male size is a predictor of quality of parental care in the broad-nosed pipefish... LÄS MER