Section 5
Table of Contents
Section 7
6. Diffusion-limited growth of sponges
A variant of the diffusion-limited growth model was proposed by Kaandorp [Kaa1992, Kaa1994] to simulate the growth of
marine sessile organisms; namely corals and sponges. Both types of
organisms develop by adding successive layers to the structure formed so
far (growth by accretion). The layer size is determined locally
by the availability of nutrients that diffuse in the water surrounding the
organism. In proximity to regions of the organism that have high
curvature, the gradient of nutrient concentration is high, and the
structure grows fast. Near flattened areas the gradient of the
concentration is lower, and the structure develops more slowly.
Consequently, a dip may occur near the center of a flattened area, causing
the emergence of a pair of new branches. The development of a hypothetical
sponge simulated using this technique is shown in Animation 2 (see caption).
Section 5
Table of Contents
Section 7