Department of Biology, Western University, London, ON, Canada.
Department of Biology, Western University, London, ON, Canada.
Gen Comp Endocrinol. 2023 Nov 1;343:114367. doi: 10.1016/j.ygcen.2023.114367. Epub 2023 Aug 19.
Parental care is critical for the survival of many young animals, but parental care can be costly to the individual providing care. To balance this cost, parents can allocate their care to offspring based on their value, which can be dependent on the offspring's relatedness to the parent. Bluegill (Lepomis macrochirus) is a fish characterized by uniparental male care and high levels of cuckoldry. While parental males of this species have been shown to adaptively adjust their care in response to paternity, the mechanisms for this adjustment are not well understood. Androgens are steroid hormones that are associated with parental care behaviours in many species including bluegill. Here, we test the hypothesis that circulating androgen concentrations mediate the adjustment in care provided by bluegill parental males by manipulating perceived paternity and then measuring circulating 11-ketotestosterone concentration and parental care behaviour. We show that males with higher perceived paternity provide higher levels of nurturing and nest defense behaviour, but contrary to expectations, we found that these males had lower concentrations of 11-ketotestosterone. Furthermore, we found positive correlations between individual circulating plasma 11-ketotestosterone concentrations and nurturing behaviour, but not with the aggressive behaviours that differed between paternity treatments. While bluegill make behavioural changes in response to perceived paternity, these changes do not appear to be modulated by 11-ketotestosterone.
亲代照顾对于许多幼小动物的生存至关重要，但亲代照顾会对提供照顾的个体造成成本。为了平衡这种成本，父母可以根据后代的价值来分配照顾，而后代的价值可能取决于与父母的亲缘关系。蓝鳃太阳鱼（Lepomis macrochirus）是一种具有雄性单亲照顾和高程度的雄寄生特征的鱼类。虽然这种物种的亲代雄性已经被证明可以适应调整他们的照顾行为以适应亲代身份，但这种调整的机制还不是很清楚。雄激素是与许多物种包括蓝鳃太阳鱼的亲代照顾行为相关的类固醇激素。在这里，我们通过操纵感知的亲代身份，然后测量循环中的 11-酮睾酮浓度和亲代照顾行为，来检验雄激素浓度是否介导了蓝鳃太阳鱼亲代雄性提供的照顾调整的假设。我们发现，感知亲代身份较高的雄性提供更高水平的养育和巢防御行为，但与预期相反，我们发现这些雄性的 11-酮睾酮浓度较低。此外，我们发现个体循环血浆 11-酮睾酮浓度与养育行为呈正相关，但与亲代处理之间不同的攻击行为无关。虽然蓝鳃太阳鱼会根据感知的亲代身份做出行为上的改变，但这些改变似乎不受 11-酮睾酮的调节。
