Evidence suggests that bacterial community spatial organization affects their ecological function, yet details of the mechanisms that promote spatial patterns remain difficult to resolve experimentally. In contrast to bacterial communities in liquid cultures, surface-attached range expansion fosters genetic segregation of the growing population with preferential access to nutrients and reduced mechanical restrictions for cells at the expanding periphery. Here we elucidate how localized conditions in cross-feeding bacterial communities shape community spatial organization. We combine experiments with an individual based mathematical model to resolve how trophic dependencies affect localized growth rates and nucleate successful cell lineages. The model tracks individual cell lineages and attributes these with trophic dependencies that promote counterintuitive reproductive advantages and result in lasting influences on the community structure, and potentially, on its functioning. We examine persistence of lucky lineages in structured habitats where expansion is interrupted by physical obstacles to gain insights into patterns in porous domains.

有证据表明，细菌群落的空间组织影响其生态功能，但促进空间模式的机制细节仍然难以通过实验解决。与液体培养物中的细菌群落相比，表面附着范围的扩展促进了不断增长的群体的遗传分离，优先获得营养，并减少了扩展外围细胞的机械限制。在这里，我们阐明了交叉喂养细菌群落的局部条件如何塑造群落空间组织。我们将实验与基于个体的数学模型相结合，以解决营养依赖性如何影响局部生长速率和使成功的细胞谱系成核。该模型跟踪单个细胞谱系，并将其归因于营养依赖性，从而促进违反直觉的生殖优势，并对群落结构及其功能产生持久影响。我们研究了结构化栖息地中幸运谱系的持久性，在这些栖息地中，扩张被物理障碍打断，以深入了解多孔领域的模式。