Biologist sees rare nautilus for the 2nd time after 30 years

No, this isn't a reference to Jules Verne's submarine though it also that unique and rare. Biologist Peter Ward from the University of Washington was more than pleased to meet an old friend, so to speak. Traveling back to Papua New Guinea in the South Pacific, the scientist had an unexpected reunion with what could be one of the most rarest animals in the world, the Allonautilus scrobiculatus, a species of nautilus, a creature that is itself a subject of interest in biology because of its ties to the past.

Nautiluses are called "living fossils" not because they are exactly that but because their distinctive shells, which almost everyone is familiar with thanks to popular science, have been recorded as far back as 500 million years. That predates even the dinosaurs. The Allonautilus is even more notable because it hasn't been sighted in over 30 years.

Its first appearance was in 1984, when Ward and Bruce Saunders from Bryn Mawr College saw the Allonautilus weeks apart, also in Papua New Guinea. No other sighting as been reported until Ward and a team of researchers came to Ndrova Island to research nautiluses. They certainly weren't expecting to see the Allonautilus again.

Not that it was hard to distinguish this particular specie. The Allonautilus has gills, jaws, and shells that were distinct from other nautilus species. The most visible difference, however, is the thick, hairy, slimy covering it had on its shell. The rarity of this nautilus as well as its difference from its cousins, support biologists theories of how immensely different, genetically and ecologically, one species is from another simply due to their location. Nautiluses are quite sensitive when it comes to their environments. They can only go so deep without dying and can't survive warm waters. These forces them to live only near corals, extremely isolated from other nautilus species.

This also presents a problem with regards to their survival. Illegal fishing and mining of nautilus shells, which are extremely popular, threaten to make them extinct. It would be a great tragedy, though sadly one that we've heard before, if these ancient creatures braved the dinosaurs and survived mass extinctions only to be finally wiped out by man.

SOURCE: University of Washington