learning from nature | Of Spirals, Shells and... 3D prints

I am always fascinated by the spiral, shape of growth and expansion -but also contraction.  Often shells are shaped as spirals, due to their growth rules, as explained in detail by D'Arcy Thompson in "On Growth and Form". The nautilus shell follows the geometry of the logarithmic spiral. I am particularly intrigued by this shape also for the septa (thin walls) partitioning the internal camerae (chambers) of the shell: the septa are interesting per se as concave-convex surfaces, proposing the spatially ambiguity of surfaces turning inside-out. I have designed and 3D printed several models of shells and nautilus but perhaps this one is my favorite:

Nature is always a great teacher, if we listen to her..

PS More of my shell design can be seen in the Shapeways shop