We recently published a method to infer ancestral landmark-based shape ontogenies that takes into account the possible existence of changes in developmental timing. Here we describe SPASOS, a software to perform that analysis. SPASOS is an open-source Windows program written in C. Input data include landmark coordinates for each specimen –with the corresponding information about developmental timing– and a phylogenetic tree showing the relationships among the species sampled. As output, the program produces image files for an easy visualization of the results and data files useful for post-processing. The program incorporates an interpolating function, based on weighting moving averages, which allows analysis of data with scarce information along the ontogenetic trajectory. An empirical evaluation of this function showed its suitability to fill in incomplete ontogenetic trajectories. Finally, we present the results of a reanalysis in SPASOS of a published dataset, where changes in developmental timing were originally inferred by considering PCA scores as shape variables. Both approaches retrieved the same four largest changes in developmental timing, but differed in the ancestral shapes inferred.

中文翻译：

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SPASOS 1.1：推断祖先形状个体发育的程序

我们最近发表了一种推断基于祖先地标的形状个体发育的方法，该方法考虑了发育时间可能存在的变化。在这里，我们描述了SPASOS，一种执行该分析的软件。SPASOS 是一个用 C 语言编写的开源 Windows 程序。输入数据包括每个标本的地标坐标——以及有关发育时间的相应信息——以及显示采样物种之间关系的系统发育树。作为输出，该程序生成图像文件，以便轻松可视化结果和用于后处理的数据文件。该程序结合了一个基于加权移动平均线的插值函数，它允许沿着个体发生轨迹分析具有稀缺信息的数据。对该功能的经验评估表明它适合填充不完整的个体发育轨迹。最后，我们展示了在已发布数据集的 SPASOS 中重新分析的结果，其中发育时间的变化最初是通过将 PCA 分数视为形状变量来推断的。两种方法都检索到了相同的四个最大的发育时间变化，但推断的祖先形状不同。