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Full-Text Articles in Ecology and Evolutionary Biology

Understanding Mechanisms Underlying Changes In Parental Care Behaviour In Response To Perceived Paternity In Sunfish, Emma Churchman Apr 2024

Understanding Mechanisms Underlying Changes In Parental Care Behaviour In Response To Perceived Paternity In Sunfish, Emma Churchman

Electronic Thesis and Dissertation Repository

Parental care is essential for the survival of many young animals but presents significant costs to the caring parent. To mitigate these costs, parental care systems have evolved to optimize survival and fitness. According to parental investment theory, care allocation is influenced by the offspring’s value, which is often linked to their relatedness to the parent. In this thesis, I explore how hormones and gene expression influence parental care, focusing on bluegill sunfish (Lepomis macrochirus) and the hybrids they produce with pumpkinseed sunfish (Lepomis gibbosus). By manipulating direct and indirect paternity cues – swapping eggs between …


Effects Of 11-Kt And Prolactin On Gene Expression, Parental Care Behaviour And Immune Response In Male Bluegill Sunfish., Adriano A P Da Cunha Jun 2023

Effects Of 11-Kt And Prolactin On Gene Expression, Parental Care Behaviour And Immune Response In Male Bluegill Sunfish., Adriano A P Da Cunha

Electronic Thesis and Dissertation Repository

Parental care is very critical for reproduction in species that provide it. Hormones such as prolactin and androgens play a crucial role in parenting and reproductive behaviours. In mammals and birds, prolactin’s role in parental care is well-established; it stimulates milk production and stimulates attachment to newborns by its release in the preoptic area of the hypothalamus (POA), among other functions. Androgens, on the other hand, are commonly associated with male secondary sex characteristics, territoriality, and aggressiveness in mammals and birds. There are similar reports of prolactin and androgen effects in fish, but there are fewer studies. I investigated if …


Fear Of Predators Compromises Parental Care And Juvenile Survival In A Songbird, Philip Blair Dudeck Dec 2015

Fear Of Predators Compromises Parental Care And Juvenile Survival In A Songbird, Philip Blair Dudeck

Electronic Thesis and Dissertation Repository

Predators kill, but the risk of being killed is also a powerful force affecting survival because scared prey eat less, thereby increasing the likelihood of starvation. Young of most animals are extremely vulnerable to predators and may alter their behaviour to limit detection. I investigated the previously unexplored effects that predation risk has on the behaviour of newly fledged offspring and their parents, and the impact this has on offspring survival. I manipulated predation risk using sound and found that parent song sparrows reduced their feedings, providing 60% less food overall. Critically, not only did this parental response estimate survival …


Effects Of Exogenous Androgens On Parental Care Behaviour In Male Bluegill Sunfish (Lepomis Macrochirus), Chandra M.C. Rodgers Apr 2012

Effects Of Exogenous Androgens On Parental Care Behaviour In Male Bluegill Sunfish (Lepomis Macrochirus), Chandra M.C. Rodgers

Electronic Thesis and Dissertation Repository

Research suggests an androgen mediated trade-off between nurturing and defensive behaviour during parental care. This research, however, comes from species with biparental care, where changes in behaviour of one parent can be compensated for by the other parent. I tested the validity of this trade-off by manipulating androgen levels in bluegill sunfish (Lepomis macrochirus), a species where males provide sole parental care. I implanted males with testosterone, 11-ketotestosterone or flutamide, an androgen receptor blocker, and tested their nurturing behaviour and aggressiveness towards a brood predator. Males implanted with 11-ketotestosterone were 64% more aggressive and 71% less nurturing than …