Albert James S, Lannoo Michael J, Yuri Tamaki
Nippon Medical School, Department of Anatomy, Sendagi 1-1-5, Bunkyo-ku, Tokyo, 113, Japan.
Muncie Center for Medical Education, Indiana University School of Medicine, Ball State University, Muncie, Indiana, 47306.
Evolution. 1998 Dec;52(6):1760-1780. doi: 10.1111/j.1558-5646.1998.tb02255.x.
In this paper, we propose a method to test alternative hypotheses of phenotypic evolution. The method compares patterns observed in phylogenetic character data with patterns expected by explicit models of evolutionary process. Observed patterns of character-state diversity are assessed from four properties of character-state change derived from a phylogenetic analysis: the sequence and correlation of transformations on a cladogram and the spatial and functional localization of these transformations to parts of an organism. Patterns expressed in terms of the localization of transformations are compared with the expectations of null models that the number of transformations is proportional to measures of size or complexity. Deviations from the values expected by the null models are then compared with qualitative expectations of the models. The method is applied to characters in the nervous system of gymnotiform electric fishes. Patterns in the diversity of 63 reconstructed character-state changes are compared with the expectations of 10 published models of neural evolution. A total of 63 expectations are reviewed, of which 33 (52%) are found to be consistent with the gymnotiform neural data. In general, the models reviewed are not successful at making global predictions, in part because they have been cast in excessively general terms. The data support the conclusion that evolution in the nervous system of gymnotiforms has involved a mosaic of processes, each operating differentially on functional and developmental systems and at different spatial and temporal scales. The results also indicate that more refined models are required, each making more explicit predictions.
在本文中，我们提出了一种检验表型进化替代假说的方法。该方法将系统发育特征数据中观察到的模式与进化过程的明确模型所预期的模式进行比较。从系统发育分析得出的特征状态变化的四个属性来评估观察到的特征状态多样性模式：分支图上转变的序列和相关性，以及这些转变在生物体各部分的空间和功能定位。将以转变定位表示的模式与零模型的预期进行比较，零模型认为转变的数量与大小或复杂性的度量成正比。然后将与零模型预期值的偏差与模型的定性预期进行比较。该方法应用于裸背电鳗目弱电鱼神经系统的特征。将63个重建的特征状态变化的多样性模式与10个已发表的神经进化模型的预期进行比较。总共审查了63个预期，其中33个（52%）被发现与裸背电鳗目的神经数据一致。总体而言，所审查的模型在进行全局预测方面并不成功，部分原因是它们表述得过于笼统。数据支持这样的结论，即裸背电鳗目神经系统的进化涉及一系列过程的拼凑，每个过程在功能和发育系统以及不同的空间和时间尺度上有不同的作用。结果还表明需要更精细的模型，每个模型都能做出更明确的预测。
