The Nautilus hasn't changed much in the past 500 million years, but it didn't always look the way it does today.  It's ancestor, Orthoceras (meaning, straight horn) lived in a straight shells.  Followed by the Lituites, which refers to a shell that is coiled in the early stage and later becomes uncoiled.  Slowly, over time, the shell has become a spiral.  This change is because the Nautilus grew its shell according to conditions and pressures in its direct environment.

The Nautilus spiral is a logarithmic spiral (or growth spiral), identified by a unique mathematical property, that being, the size of the spiral increases but the shape remains unaltered with each successive curve.  A property known as self-similarity.  This type of spiral was first described by Descartes and later extensively investigated by Jacob Bernoulli who called it, Spira mirabilis, "the marvelous spiral."

A small instruction in the genetic code prompted by a change in the environment is what created the form we recognize as the Nautilus shell today.  

Likewise, this lighting sculpture has an environment to which is must adapt.  In this rendering it is a stairwell of a particular height and width.  And so, the rules of growth are modified to create a spiral that is recursive.  Instead of closing in on itself, the form opens up and out.

In the center of this particular sculpture where the chambers are smaller, the light points will curl inward, making the sculpture glow from within.  As the chambers grow larger, towards the ends of the sculpture, the light points will gradually curl outward - making the glow more exterior.  In the actual sculpture, as in the Nautilus shell, these changes will be nuanced translating visually as an elegant and fluid line created by the many, many delicate light points.

The shape of the sculpture's individual chambers are determined by the variation in the width of each successive chamber strip.  This is worked out in the design program by using curves and equations analogous to the curves found in the evolutionary progression of the Nautilus suture lines.

As the curve of the sculpture changes, the size, and ever so slightly the shape of each chamber will also change.  The result, an elegant fluid pattern created by the gaps between the unique edges of the combined chambers along the full length of the sculpture.

Nautilus are the only living cephalopod to have an external shell.  

They have blue blood.  This is because Nautilus blood contains hemocyanin, which is blue in its oxygenated state due to being copper based rather than iron based like our blood.