(rā’dē-ō-lâr’ē-ən) n. Any of various marine protozoans of the order Radiolaria, having rigid siliceous skeletons and spicules. (American Heritage Dictionary.)

Below is a 3-Step theme describing radiolarian functions of growth and geometry in descriptive terms and graphically with sections through a digital model (produced with Rhino) of the radiolarian’s dynamic relationship between cell and skeleton. The radiolarian’s central cell collects materials from the ocean, creating a skeletal aperture, which grows as the cell grows to build it. Skeleton protects cell until the cell outgrows the innermost skeletal layer and is forced to thread through the apertures it’s created.