Department of Ecology and Evolutionary Biology, 1200 Sunnyside Ave., University of Kansas, Lawrence, Kansas 66045.
Integr Comp Biol. 2003 Feb;43(1):82-6. doi: 10.1093/icb/43.1.82.
Colonial hydrozoans represent some of the most diverse and complex body plans within the Metazoa. Complex hydrozoans colonies are more physiologically and structurally integrated than their simple colonial relatives. Colonial integration is commonly associated with the regulation of the general structural plan of the colony, the division of labor, and the physiological integration of the colony. In the hydrozoan Hydractinia, these features are manifested through evolutionary innovations involving the spatial regulation of polyps within the colony, the development of polyp polymorphs, and the acquisition of a stolonal mat. These innovations all involve evolutionary changes in the regulation of polyp and colony-wide patterning systems. In Hydractinia, the ParaHox gene, Cnox-2, is expressed in a spatially restricted manner along the axes of stolons and polyps, suggesting that changes in the regulation of this gene may be in part responsible for the evolutionary innovations important for colonial complexity.
殖民地水螅动物代表了后生动物门中最具多样性和复杂性的身体计划之一。复杂的水螅动物殖民地比其简单的殖民地亲属在生理和结构上更加整合。殖民地的整合通常与调节殖民地的一般结构计划、分工以及殖民地的生理整合有关。在水螅动物海月水母中，这些特征通过涉及在殖民地内调节水螅体的空间、多态水螅体的发育以及获得匍匐枝垫的进化创新得以体现。这些创新都涉及调节水螅体和全殖民地模式系统的进化变化。在海月水母中，ParaHox 基因 Cnox-2 沿着匍匐枝和水螅体的轴以空间限制的方式表达，表明该基因调控的变化可能部分负责对殖民地复杂性很重要的进化创新。
