Merks Roeland M H, Hoekstra Alfons G, Kaandorp Jaap A, Sloot Peter M A
Faculty of Science, Section Computational Science, University of Amsterdam, Kruislaan 403, 1098 SJ Amsterdam, The Netherlands.
J Theor Biol. 2004 Jun 21;228(4):559-76. doi: 10.1016/j.jtbi.2004.02.020.
The morphogenesis of colonial stony corals is the result of the collective behaviour of many coral polyps depositing coral skeleton on top of the old skeleton on which they live. Yet, models of coral growth often consider the polyps as a single continuous surface. In the present work, the polyps are modelled individually. Each polyp takes up resources, deposits skeleton, buds off new polyps and dies. In this polyp oriented model, spontaneous branching occurs. We argue that branching is caused by a so called "polyp fanning effect" by which polyps on a convex surface have a competitive advantage relative to polyps on a flat or concave surface. The fanning effect generates a more potent branching mechanism than the Laplacian growth mechanism that we have studied previously. We discuss the application of the polyp oriented model to the study of environmentally driven morphological plasticity in stony corals. In a few examples we show how the properties of the individual polyps influence the whole colony morphology. In our model, the spacing of polyps influences the thickness of coral branches and the overall compactness of the colony. Density variations in the coral skeleton may also be important for the whole colony morphology, which we address by studying two variants of the model. Finally, we discuss the importance of small scale resource translocation in the coral colony and its effects on the morphology of the colony.
群体石珊瑚的形态发生是许多珊瑚虫在它们所生活的旧骨骼顶部沉积珊瑚骨骼的集体行为的结果。然而，珊瑚生长模型通常将珊瑚虫视为一个单一的连续表面。在当前的工作中，对珊瑚虫进行了单独建模。每个珊瑚虫获取资源、沉积骨骼、萌发出新的珊瑚虫并死亡。在这个以珊瑚虫为导向的模型中，会出现自发分支。我们认为分支是由一种所谓的“珊瑚虫扇动效应”引起的，通过这种效应，凸面上的珊瑚虫相对于平面或凹面上的珊瑚虫具有竞争优势。这种扇动效应产生了一种比我们之前研究的拉普拉斯生长机制更有效的分支机制。我们讨论了以珊瑚虫为导向的模型在研究石珊瑚环境驱动的形态可塑性方面的应用。在一些例子中，我们展示了单个珊瑚虫的特性如何影响整个群体的形态。在我们的模型中，珊瑚虫的间距会影响珊瑚分支的厚度和群体的整体紧凑性。珊瑚骨骼中的密度变化对整个群体形态也可能很重要，我们通过研究模型的两个变体来解决这个问题。最后，我们讨论了珊瑚群体中小规模资源转移的重要性及其对群体形态的影响。
