Multispecies microbial adherent communities are widespread in nature and organisms, although the principles of their assembly and development remain unclear. Here, we test the possibility of establishing a simplified but relevant model of multispecies biofilm in a non-invasive laboratory setup for the real-time monitoring of community development. We demonstrate that the four chosen species (Bacillus thuringiensis, Pseudomonas fluorescens, Kocuria varians, and Rhodocyclus sp.) form a dynamic community that deterministically reaches its equilibrium after ~30 h of growth. We reveal the emergence of complexity in this simplified community as reported by an increase in spatial heterogeneity and non-monotonic developmental kinetics. Importantly, we find interspecies interactions consisting of competition for resources—particularly oxygen—and both direct and indirect physical interactions. The simplified experimental model opens new avenues to the study of adherent bacterial communities and their behavior in the context of rapid global change.

多物种微生物粘附群落在自然界和生物体中广泛存在，尽管它们的组装和发育原理仍不清楚。在这里，我们测试了在非侵入性实验室设置中建立简化但相关的多物种生物膜模型以实时监测社区发展的可能性。我们证明了四种选择的物种（苏云金芽孢杆菌、荧光假单胞菌、Kocuria varians和Rhodocyclussp.) 形成一个动态群落，在生长约 30 小时后确定性地达到平衡。我们揭示了这个简化社区中复杂性的出现，正如空间异质性和非单调发展动力学的增加所报道的那样。重要的是，我们发现种间相互作用包括对资源（尤其是氧气）的竞争以及直接和间接的物理相互作用。简化的实验模型为研究粘附细菌群落及其在全球快速变化背景下的行为开辟了新途径。