[2] The oldest fossils of the genus are known from the Late Eocene Hoko River Formation, in Washington State and from Late-Eocene to Early Oligocene sediments in Kazakhstan.

[1] The oldest fossils of the modern species Nautilus pompilius are from Early Pleistocene sediments off the coast of Luzon in the Philippines.

[4] The genus Nautilus includes several species represented in the fossil record; however, these have also been contentious in their placement, and some are only provisionally accepted.

[6] The classification of species within Nautilus has been contentious for decades, and the genus has been reconfigured and redefined several times throughout its history.

Nautilus is the type genus of the family Nautilidae, originally defined as any coiled-shell species with simple sutures, or walls, between shell compartments.

This definition persisted for nearly 200 years, from the time of the genera's 1758 inception by Carl Linnaeus to 1949, when paleobiologist Arthur K. Miller provided a detailed description of the shell of N. pompilius, becoming the type species of the genus.

[4] In 2021, a review of the evidence concluded that the recognition of exclusively-fossil genera was largely arbitrary, instead recognising numerous extinct species within the genus Nautilus.

[5] Several genetic studies have also been conducted on select species of Nautilus, from 1995 onwards, most of which focus on a single gene, called COI.

[13] The divergence between the genus Nautilus, and its sister taxon Allonautilus likely occurred around New Guinea, and the Great Barrier Reef,[13] during the Mesozoic.

[2] From there, populations of Nautilus split diverged further, involving migrations east to Vanuatu, Fiji, and American Samoa, as well as west, to the Philippines, Palau, Indonesia, and western Australia.

[15] Species within the genus Nautilus are localised to the Indo-Pacific, specifically the tropical seas within this area,[7] however the full extent of their geographic distribution has yet to be recorded.

[4] Nautilus can occasionally be found closer to the surface than 100 metres, however, the minimum depth they can reach is determined by factors such as water temperature and season.

Shells have been found across a wide range of coastal areas, including Korea, Australia, Seychelles, Mauritius, the Philippines, Taiwan, Japan, Thailand, India, Sri Lanka, Kenya, and South Africa.

[4] Furthermore, shells have been demonstrated to drift considerable distances in this time, contributing to their extensive distribution across coastal areas.

Nautilus return to deeper areas following daybreak and also lay eggs in these locations, which take approximately one year to hatch.

[18][4] The feeding behaviour of the genus has been identified from observation of captive individuals, as well as the stomach contents of wild specimens.

The survival rate of Nautilus in captivity is relatively poor, primarily due to the stress that individuals are subjected to during transportation.

[4][19] Several aquaria around the world host specimens of the genus, however, there have not yet been any successful attempts of breeding in captivity, despite viable eggs being produced at several locations.

[19] In addition to observing wild specimens, our knowledge of Nautilus temperature thresholds is also supplemented by the study of captive individuals in aquaria.

Captive Nautilus specimens have demonstrated that prolonged exposure to temperatures over 25 degrees Celsius will eventually result in death after several days.