Seed dispersal curves: Behavior of the tail of the distribution
Seed dispersal curves: Behavior of the tail of the distribution
复制标题
种子传播曲线：分布尾部的行为
DOI：
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发表时间：
2005
影响因子：
1.9
通讯作者：
M. Willson
中科院分区：
文献类型：
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作者：
S. Portnoy;M. Willson
种子传播对植物适合度和种群结构都有重要意义。我们建议，种子传播曲线的尾部至少是重要的生物学曲线的模态部分，我们提出了一个相对简单的，四参数模型，扩散原理的基础上，种子分布的尾部。该模型包括两种类型的定性行为：代数尾（往往更长，具有更大的“范围”）和指数尾（更短，具有更小的“范围”）。我们从文献中选择了68个数据集，每个数据集都给出了一个种子阴影，可以在统计学上归类为（1）指数，（2）代数，（3）两者都不适合，或（4）两个模型都适合。种子阴影尾部的代数形状在这个样本中很常见，尾部行为通常不特定于特定的传播模式。这一结果可能表明，代数尾一般有利于选择，可以通过几种手段来实现，但现有的数据集和统计方法的限制，排除最终的判断。较小的完整样本的种子距离将提供一个更好的基础，尾部的分析比目前形式的数据集（包括离散距离类别的种子计数）。
SummarySeed dispersal is important both to plant fitness and to plant population structure. We suggest that the tail of the seed dispersal curve is at least as important biologically as the modal portion of the curve, and we present a relatively simple, four-parameter model, based on diffusion principles, for the tail of the seed distribution. This model includes two types of qualitative behavior: algebraic tails (which tend to be longer and have greater ‘reach’) and exponential tails (which are shorter and have less ‘reach’). We have selected 68 data sets from the literature, each giving a seed shadow that could be categorized statistically as (1) exponential, (2) algebraic, (3) neither, or (4) both models fit adequately. Algebraic shapes for seed-shadow tails were common in this sample, and tail behavior was not generally specific to a particular dispersal mode. This result may suggest that algebraic tails are generally favored by selection and can be achieved by several means, but limitations of existing data sets and of statistical methodology preclude final judgement. Smaller complete samples of seed distances would provide a better basis for the analysis of tails than do the present form of data sets (consisting of counts of seeds in discrete distance categories).