The Chambered Nautilus: Nautilus pompilius

Classification:
Kingdom Animalia
Phylum Mollusca
Class Cephalopoda, Subclass Nautiloidea
Order Tetrabranchia
Family Nautiloidea
Genus Nautilus

The Chambered Nautilus has existed relatively unchanged for over 500 million years. Despite its appearance, it is most closely related to the cuttlefish, squid and octopus. Numerous Nautiloid varieties existed in prehistoric times however only a few are not extinct. The Nautilus was the dominant marine predator of the Ordovician period, 450 million years ago before the existence of fish.

The Nautilus exists on a diet of small fish and crustaceans and is capable of migrating through a wide depth range seen in a few other marine animals. Relatively little is known about the marine environment in which the Nautilus lives. It spends much of its life along the deep sloped edges off coastal reefs at depths to 450 metres.

The Nautilus would appear to take up to 10-year is to reach maturity, then produces perhaps a dozen eggs per year and can live as long as 20 years. It has about 38 tentacles that it uses to ensnare its prey. It travels slowly by jet propulsion alternately drawing water into the mantle and expelling it through a muscular siphon between its tentacles. It can direct this siphon to move in various directions.

Unlike its cephalopod relatives, the cuttlefish, squid and octopus, the Nautilus has an external shell to support its soft body. Unlike its distant relative, the snail, the Nautilus has a chambered shell. Its most familiar characteristic is its smooth, coiled shell, up to 11 inches in diameter. The shell is lined with mother-of-pearl and is separated into a series of progressively larger compartments; the most recent of which is inhabited by the animal. The walls (septa) dividing the chambers are pierced by a tube (siphuncle) connected to the nautilus. Gas and liquid exchange occurs through the siphuncle walls, by means of which the nautilus can regulate its buoyancy. The shell is produced by mantle tissue and will contain up to 30 Chambers in a mature adult. As the animal grows it produces a wall behind it sealing off the previous chamber. The main functions of the shell are protection and the control of buoyancy.

From the time of ancient Greece the coiled spiral of the Nautilus shell has fascinated man because of its perfect logarithmic proportions.

It is nature's assimilation of beauty and perfection that makes the Chambered Nautilus an ideal logo for our clinic.

Perfection in form