Hamon Troy R
School of Aquatic and Fisheries Sciences, University of Washington, Box 355020, Seattle, Washington 98195-5020, USA.
Evolution. 2005 May;59(5):1096-103.
Current methods for measuring selection with longitudinal data have been developed with the assumption that episodes of selection are sequential. However, a number of empirical examinations have demonstrated that natural and sexual selection may act concurrently and in opposing directions. Other recent work has highlighted the difficulty of assigning fitness values for survival when reproduction and mortality within a population temporally overlap. I treat these as facets of a single problem; how to analyze selection where mortality and reproduction are concurrent. To address this problem, I formalize a method to estimate total fitness of individuals over a period of time utilizing longitudinal data. I then show how the fitness may be partitioned to provide two separate estimates of fitness for reproductive opportunity and reproductive success. In addition, another total fitness estimate for the period can be obtained from the two partitioned estimates. This procedure will allow calculation of total fitness where there are some missing datapoints for reproductive success of an individual. A simulation indicates that bias is generally low for the various fitness estimates. These methods should expand our ability to understand the interaction of different selection episodes.
当前用于通过纵向数据测量选择的方法是在选择事件是相继发生的假设下开发的。然而，一些实证研究表明，自然选择和性选择可能同时以相反的方向起作用。最近的其他研究强调了在种群内繁殖和死亡在时间上重叠时为生存分配适合度值的困难。我将这些视为一个单一问题的不同方面；即如何分析死亡率和繁殖同时发生时的选择。为了解决这个问题，我形式化了一种利用纵向数据估计个体在一段时间内总适合度的方法。然后我展示了如何对适合度进行划分，以提供对繁殖机会和繁殖成功的两个单独的适合度估计。此外，该时间段的另一个总适合度估计可以从两个划分后的估计中获得。此程序将允许在个体繁殖成功存在一些缺失数据点的情况下计算总适合度。模拟表明，各种适合度估计的偏差通常较低。这些方法应能扩展我们理解不同选择事件相互作用的能力。
