Biologist Peter Ward, a professor at the University of Washington, and his colleagues recently came face-to-face with a nautilus⎯one of the rarest creatures of the world⎯after a 30-year long hiatus. Last seen in 1984, nautiluses are distant cousins of squids and cuttlefish and have distinctive shell patterns.
Nautiluses are “living fossils” reflecting lineages dating back to millions of years
The rare nautilus was sighted at the Ndrova Island at Papua New Guinea; its biological name is Allonautilus scrobiculatus. Nautilus is an ancient member of the phylum Mollusca under the class Cephalopoda, which is home to many other modern sea creatures like the octopus and cuttlefish. Amongst the first cephalopods to inhabit the earth, their first appearance can be traced back 500 million years⎯a time before dinosaurs walked the earth. Nautiluses are sometimes called living fossils because they carry within the intricate patterns on their shells, remnants of a period we know little about.
The biologists used baits to attract the nautilus
The initial sighting in 1984 gave Ward a good idea of the physical characteristics of the nautilus: It has a thick, hairy, slimy covering on the shell, and is an expert scavenger. Ward and his colleagues therefore knew what to look for and how to reel it in. They used fish and chicken meat as bait on a stick suspended 500-1300 feet below the water surface, and recorded movies of any activity around the bait. After many such videos showing no activity, one of them showed an Allonautilus followed by another tug at the bait. The researchers brought them up to the surface, collected tissue and shell samples and released them back to the sea. From the studies they conducted on the samples, they realized that most nautilus populations are isolated because only some ocean depths are conducive to their existence. This separates nautiluses geographically, and eventually, genetically, making them difficult to sight or study.
Nautiluses are in danger of extinction
Owing to their beautiful shells and their inner shell layer, which is used as a pearl substitute, nautiluses are prime candidates for illegal mining. This and their geographical isolation have demolished the nautilus population worldwide. Efforts are currently on, to advocate for the preservation of this tiny, rare tie to our past.