Sources of variation in maternal allocation in a long-lived mammal

Life history theory predicts allocation of energy to reproduction varies with maternal age but additional maternal features may be important to the allocation of energy to reproduction. We aimed to characterize age-specific variation in maternal allocation and assess the relationship between maternal allocation and other static and dynamic maternal features. Mass measurements of 531 mothers and pups were used with Bayesian hierarchical models to explain the relationship between diverse maternal attributes and both the proportion of mass allocated by Weddell seal mothers, and the efficiency of mass transfer from mother to pup during lactation as well as the weaning mass of pups. Our results demonstrated that maternal mass was strongly and positively associated with the relative reserves allocated by a mother and a pup’s weaning mass but that the efficiency of mass transfer declines with maternal parturition mass. Birthdate was positively associated with proportion mass allocation and pup...

生活史理论（Life history theory）预测，生物繁殖过程中的能量分配会随母体年龄发生变化，但其他母体特征同样可能对繁殖相关的能量分配起到关键作用。本研究旨在表征母体能量分配的年龄特异性变异规律，并评估母体能量分配与其他静态、动态母体特征之间的关联。本研究采用531头母兽及其幼崽的体重测量数据，结合贝叶斯分层模型（Bayesian hierarchical models），解析多种母体属性与威德尔海豹（Weddell seal）母体的体重分配比例、泌乳期母体向幼崽的体重转移效率，以及幼崽断乳体重（weaning mass）三者间的关联。研究结果显示，母体体重与母体留存的相对能量储备及幼崽断乳体重均呈显著正相关，但体重转移效率会随母体分娩体重的增加而下降。出生日期与体重分配比例及幼崽……