News Animals

Argonauts use shells as flotation devices

Octopus relatives gulp and store air from the surface

By Susan Milius

- More than 2 years ago

After centuries of speculation, biologists have documented one way a strange group of octopuslike creatures use their seashell-shaped cases.

UPPER CASE A female argonaut bobs just under the surface in the Sea of Japan. New observations suggest that the animals use their seashell-shaped cases for buoyancy control. Julian Finn, Museum Victoria

Female argonauts, a group of four species that are close cousins of octopuses, grow delicate white shell-like cases.