Trans-generational immune priming & sexual immune dimorphism across a parental care gradient in two fish families

雄性和雌性的生活史策略不同，这是由于它们的生殖成分的异配生殖。在传统的性别角色物种，女性健身与寿命呈正相关，而男性的选择增加交配率。这也反映在性免疫二型性中，表明雌性通常需要比雌性更强的免疫防御来有效地对抗寄生虫和病原体。此外，由于机制和进化的限制，只有雌性才能将免疫力传递给后代，而在父系照顾增加的物种中，这些原则可能会下降。随着父亲对后代的投资增加，我们假设性免疫二型性是颠倒的：如果父亲的投资更高，男性应该比女性有更大的免疫防御，因为现在他们是限制性的性别。此外，如果后代出生在父亲的环境中，父亲应该被选择，以提高后代的免疫系统，因为他们将暴露在类似的寄生虫的压力。我们要调查这些进化的概念，在两个鱼类家庭的父母投资梯度，海龙和慈鲷。通过对直接免疫防御和免疫基因的广泛采样和评估，我们希望确定田间不同物种的免疫活性，以确定性免疫二型性和免疫防御动力学的诱导。作为第二个目标，我们希望通过基线测量和激素水平的实验操作来解决性免疫二型性的机械激素基础，然后我们希望调查慈鲷和鱼类的双亲免疫启动的一般性，并评估母亲与父亲的免疫启动的成本。这将使用交叉培养方法和广泛的育种实验来完成。这个项目将加强我们对免疫防御进化的选择压力的理解，并确定父母照顾对免疫防御dyesterol和寄生虫防御的影响。

Males and females have different life-history strategies due to the anisogamy of their reproductive elements. In conventional sex role species, female fitness is positively correlated with longevity, whereas males are selected for increasing mating rates. This is also reflected in the sexual immune dimorphism suggesting that females usually need a greater immune defence than females to efficiently fight parasites and pathogens. In addition, only females transfer immunity to their offspring due to both mechanistic and evolutionary constraints.In species with increased paternal care, these principles may fall. With higher paternal investment into offspring we hypothesize sexual immune dimorphism to be inverted: if paternal investment is higher, males should have a greater immune defence than females as now they are the limiting sex. In addition, if offspring are born in paternal environment, fathers should be selected to boost the offspring immune system as they will be exposed to similar parasite pressures.We want to investigate these evolutionary concepts in two fish families with a parental investment gradient, Syngnathids and Cichlids. With extensive sampling and assessment of direct immune defence and immune genes we want to determine the immunocompetence of different species in the field to determine sexual immune dimorphism and the inducibility of immune defence dynamics. As a second goal we want to address the mechanistic hormonal basis of sexual immune dimorphism via both baseline measuring and experimental manipulation of the hormone level.We then want to investigate the generality of bi-parental immune priming in both cichlids and fish and evaluate the costs of maternal versus paternal immune priming. This will be done using cross-fostering approach and extensive breeding experiments. This project will enhance our understanding of selection pressures of immune defence evolution and determine the effect of parental care on immune defence dyamics and parasite defence.