Department of Evolution and Ecology, University of Kansas, Lawrence, Kansas, USA.
J Exp Zool B Mol Dev Evol. 2021 Apr;336(3):293-299. doi: 10.1002/jez.b.22996. Epub 2020 Aug 15.
Hydrozoan colonies display a variety of shapes and sizes including encrusting, upright, and pelagic forms. Phylogenetic patterns reveal a complex evolutionary history of these distinct colony forms, as well as colony loss. Within a species, phenotypic variation in colonies as a response to changing environmental cues and resources has been documented. The patterns of branching of colony specific tissue, called stolons in encrusting colonies and stalks in upright colonies, are likely under the control of signaling mechanisms whose changing expression in evolution and development are responsible for the diversity of hydrozoan colony forms. Although mechanisms of polyp development have been well studied, little research has focused on colony development and patterning. In the few studies that investigated mechanisms governing colony patterning, the Wnt signaling pathway has been implicated. The diversity of colony form, evolutionary patterns, and mechanisms of colony variation in Hydrozoa are reviewed here.
水螅群体呈现出多种形状和大小，包括附生、直立和浮游形式。系统发育模式揭示了这些不同群体形式以及群体丧失的复杂进化历史。在一个物种内，已经记录了群体对环境线索和资源变化的表型变异。群体特有的组织分支模式，在附生群体中称为匍匐茎，在直立群体中称为茎干，可能受到信号机制的控制，这些信号机制在进化和发育过程中的表达变化导致了水螅群体形式的多样性。尽管息肉发育的机制已经得到了很好的研究，但很少有研究关注群体的发育和模式形成。在少数研究中，调查了控制群体模式形成的机制，涉及到 Wnt 信号通路。本文综述了水螅群体形式的多样性、进化模式和群体变异的机制。
