Variability and the Population Biology of Marine Organisms

许多海洋生物的特点是个体的大小变化很大，特别是在早期生活史中。本研究的目标是：1)量化自然种群中的这种变异，2)确定变异是否随时间传播，3)评估规模和生长变化是否有人口统计学后果，4)量化规模和生长变化对种群模型的影响。解决这一问题的方法将是多元的，包括对实地个体的观察，对易控制种群的实验操作，以及包括个体特征的种群建模。观察和实验数据将从几种不同的物种中收集，包括藻类、帽贝和近岸鱼，它们在分类和生活史上都不同。实验将确定变异本身是否可以通过操纵种群中变异的数量和类型来影响未来的种群轨迹。在整个研究过程中，将通过跟踪标记个体的命运来收集个体层面的信息。在观察和实验中，将被量化的关键生物学特征包括个体生长，生长速率是否随时间相关，存活率，以及所有这些特征在个体之间变化的倾向。这些分析将对比包括个体之间可变性的模型（基于个体的模型）和那些使用生物体属性平均值的模型（矩阵种群模型）的结果。这项工作的重要性来自于认识到理解为什么海洋生物的招募变化可能需要包括个体属性。

Many species of marine organisms are characterized by high variation in the size of individuals, especially during the early life history. The objectives of the proposed research are to: 1) quantify this variability in natural populations, 2) determine whether variability is transmitted through time, 3) assess if there are demographic consequences of size and growth variation, and 4) quantify the effects of size and growth variation on population models. The approach to the problem will be pluralistic, including observations of individuals in the field, experimental manipulation of tractable populations, and population modeling where individual traits are included. Observational and experimental data will be gathered from several species that differ in their taxonomy and life history, including an alga, a limpet and a nearshore fish. Experiments will determine if variation alone can affect future population trajectories by manipulating the quantity and type of variability in a population. Throughout the study, information will be gathered at the level of the individual by following the fate of marked individuals. In both observations and experiments, the key biological features that will be quantified include individual growth, whether growth rates are correlated through time, survivorship, and the propensity for all these traits to vary among individuals. The analyses will contrast the outcome of models which include variability among individuals (individual based models) versus those that use a mean value for organism attributes (matrix population models). The importance of this work draws from a recognition that understanding why recruitment varies in marine organisms may require the inclusion of individual attributes.