Bone Elisa K, Keough Michael J
Department of Zoology, The University of Melbourne, Victoria 3010, Australia.
Biol Bull. 2010 Dec;219(3):220-30. doi: 10.1086/BBLv219n3p220.
A colonial lifestyle necessitates communication between colony members to coordinate functions and enable resource sharing through physiological integration. Colonial integration is predicted to increase with both the size of the colony and the level of specialization (polymorphism). In modular colonies, although integration might be reflected in structural characteristics such as module spacing or branching patterns, physiological integration is fundamentally dependent on the level of connectedness between modules. In cheilostome bryozoans, funicular tissue links adjacent zooids through pores within zooid walls and is the most likely means of nutrient transport within colonies. We sought to determine whether the relative numbers of pores (septulae) and pore plates (septal chambers) per zooid differed across colony regions in a monomorphic species, Watersipora subtorquata, and one showing some polymorphism, Mucropetraliella ellerii. Within each species, the morphology of pore plates corresponded to functional predictions based on their position within the zooid, and connection numbers per zooid increased with colony size. Contrary to expectations, however, the more complex species, M. ellerii, had significantly fewer porous connections per zooid than W. subtorquata. Physiological connectedness was therefore not predicted by simple assessment of polymorphism in these species and may not be sufficient to infer colonial integration in related taxa.
群体生活方式需要群体成员之间进行交流，以协调各项功能，并通过生理整合实现资源共享。预计群体整合会随着群体规模和专业化程度（多态性）的增加而增强。在模块化群体中，尽管整合可能体现在模块间距或分支模式等结构特征上，但生理整合从根本上取决于模块之间的连接程度。在唇口目苔藓虫中，索状组织通过虫室壁上的小孔连接相邻的个虫，这是群体内营养物质运输最可能的方式。我们试图确定，在单态物种亚扭瓦特斯苔藓虫和表现出一定多态性的埃氏微苔藓虫中，每个个虫的小孔（隔膜）和孔板（隔膜腔）的相对数量在群体不同区域是否存在差异。在每个物种中，孔板的形态与基于其在个虫内位置的功能预测相符，并且每个个虫的连接数随群体大小增加。然而，与预期相反，更复杂的物种埃氏微苔藓虫每个个虫的多孔连接显著少于亚扭瓦特斯苔藓虫。因此，在这些物种中，不能通过简单评估多态性来预测生理连接性，并且这可能不足以推断相关类群中的群体整合情况。
