Finding shells on the beach
When walking on the beaches around the world, shells from mussels and snails can be found. Along the South African coastline egg casings from sharks and rays as well as sea urchins and cuttlefish bones are found on a regular basis. Most areas also have a specific type of shell that is only found there e.g. in Plettenberg Bay the special shell to find is a Pansy shell, and special for the South African coastline is to find a Paper Nautilus shell.
The Paper Nautilus belongs to a group of pelagic octopuses (Argonauts) where the females create a paper-thin egg casing that gives them their name. The shell is gas filled and is used as a brood chamber to keep the young ones safe.
The Argonauts are found in tropical and subtropical waters worldwide. As a pelagic species they live in the open ocean and not on the bottom as most octopuses do. They look like all other octopuses with eight arms and a round body, but have smaller eyes and a funnel-mantle apparatus that can be folded over the shell for camouflage.
The beautiful looking shells we find on the beaches are in real life the nursery for the Paper Nautilus.