Arthropod segmentation and vertebrate somitogenesis are leading fields in the experimental and theoretical interrogation of developmental patterning. However, despite the sophistication of current research, basic conceptual issues remain unresolved. These include: (i) the mechanistic origins of spatial organization within the segment addition zone (SAZ); (ii) the mechanistic origins of segment polarization; (iii) the mechanistic origins of axial variation; and (iv) the evolutionary origins of simultaneous patterning. Here, I explore these problems using coarse-grained models of cross-regulating dynamical processes. In the morphogenetic framework of a row of cells undergoing axial elongation, I simulate interactions between an ‘oscillator’, a ‘switch’ and up to three ‘timers’, successfully reproducing essential patterning behaviours of segmenting systems. By comparing the output of these largely cell-autonomous models to variants that incorporate positional information, I find that scaling relationships, wave patterns and patterning dynamics all depend on whether the SAZ is regulated by temporal or spatial information. I also identify three mechanisms for polarizing oscillator output, all of which functionally implicate the oscillator frequency profile. Finally, I demonstrate significant dynamical and regulatory continuity between sequential and simultaneous modes of segmentation. I discuss these results in the context of the experimental literature.

节肢动物分割和脊椎动物体节发生是发育模式的实验和理论研究的主要领域。然而，尽管目前的研究很复杂，但基本的概念问题仍未解决。这些包括：（i）段添加区（SAZ）内空间组织的机械起源；(ii) 分段极化的机制起源；(iii) 轴向变化的机械起源；(iv) 同时模式的进化起源。在这里，我使用交叉调节动态过程的粗粒度模型来探索这些问题。在经历轴向伸长的一排细胞的形态发生框架中，我模拟了一个“振荡器”、一个“开关”和最多三个“计时器”之间的相互作用，成功地再现了分割系统的基本模式行为。通过将这些很大程度上是细胞自主模型的输出与包含位置信息的变体进行比较，我发现缩放关系、波浪模式和模式动力学都取决于 SAZ 是否受时间或空间信息的调节。我还确定了三种极化振荡器输出的机制，所有这些机制在功能上都与振荡器频率分布有关。最后，我展示了连续和同时分割模式之间的显着动态和监管连续性。我在实验文献的背景下讨论了这些结果。波浪模式和模式动力学都取决于 SAZ 是否受时间或空间信息的调节。我还确定了三种极化振荡器输出的机制，所有这些机制在功能上都与振荡器频率分布有关。最后，我展示了连续和同时分割模式之间的显着动态和监管连续性。我在实验文献的背景下讨论了这些结果。波浪模式和模式动力学都取决于 SAZ 是否受时间或空间信息的调节。我还确定了三种极化振荡器输出的机制，所有这些机制在功能上都与振荡器频率分布有关。最后，我展示了连续和同时分割模式之间的显着动态和监管连续性。我在实验文献的背景下讨论了这些结果。