Last week I had a rare encounter with Paper Nautilus in the shallows of Port Phillip Bay in Melbourne, Australia. It was a rather sad event. Every seven years or so they congregate near the coast to spawn. No-one really knows whether this is a normal end-of-life process. Paper nautilus breed more than once but some are bound not to survive, as reproduction takes a heavy toll. The exhausted animals we find inshore are likely to victims of natural selectionDarwin’s theory how species are formed, where those that stand in closest competition with those undergoing beneficial modification and improvement, will go extinct faster. Natural selection is by survival of the likeliest, not survival of the fittest. The fittest are only likely to survive because they happen to be most suited to the environment into which they are born. The More. Paper nautilus are an ocean mystery but that’s one of the great things about exploring the sea. We know so little, these precious encounters are a reminder of how important it is to preserve life.
Paper nautilus are an argonaut not a nautilus
Paper nautilus are argonauts, a type of octopus. Orange and white-striped Chambered Nautilus are different animals altogether. Their biology is more like in snails where the body and shell are connected. In argonauts only the female has the papery shell and it is grown on the outside, so they can protect and nurture their eggs. Nonetheless, along with cuttlefish and squid, both nautilus and octopuses are in the class Cephalapoda, meaning ‘head of feet’.
Argonauts are able to extract calcium from the ocean food chainA single thread in a food web illustrating the chain of animals that eat each other. At the base of the food chain are small high-energy (fast metabolism) animals and at the other end large low metabolism animals. An example would be whales eating krill that eat plankton that eat algae. Or lions that eat gazelles that eat grass. More to build their calcite cover. Ocean currents will eventually sweep any eggs into the open ocean once they hatch, to become part of the planktonA soup of micro-organisms. Usually refers to all the zooplankton and algae in the ocean but can also be used to describe tiny insects in the atmosphere (see aerial plankton). More soup that circulates the Earth.
Male argonauts are from Mars, females are from Venus
The female we found in Port Phillip Bay was about 20cm across but the male that fertilised her would have been only 2-3cm. This difference in size is more than matched by a completely different lifestyle and behaviour. No-one knows how they get together, since the females’ shell is also a buoyancy device and she is highly mobile. Maybe the males live on the seabed? Males are tiny, free swimming and would otherwise be at the mercy of ocean currents.
Each tentacle has its own brain. In other words, the male’s penis has a mind of its own.
When they do procreate, it’s one of the stranger activities of the animal kingdom.
Males don’t have shells but they do have a detachable penis … yes, you heard that right. After mating, this sperm-carrying appendage (a modified tentacle) continues to survive and attaches onto the female’s gill cavity. No doubt that’s a great reproductive strategy when your chance of encounter is rare.
A rare intelligence
Some scientists suppose that male argonauts die after reproduction but that’s a rather anthropocentric view of an animal that lives a life as alien as we might imagine. It makes more sense when you consider that each tentacle has its own brain. In other words, the male’s penis has a mind of its own! I’m sure many of my readers can empathise with that.
The male doesn’t so much die, as continue to survive, albeit in a reduced form but with unmitigated focus on its own reproductive function(Of an ecosystem). A subset of ecosystem processes and structures, where the ecosystem does something that provides an ecosystem service of value to people. More.
When it comes to intelligence, most of us humans have it all wrong. Intelligence is the ability to connect with your environment, survive for the longest and contribute the most back to the stability of life on Earth.
In my experience, when you look into the eye of an animal like an argonaut, you are seeing a level of awareness and sophistication that exceeds our own imagining. Some of the most important animals on Earth are the ones that have to survive against all odds, in a world that is harsh and unforgiving. Ocean animals have to be super-intelligent to make things habitable for us too.
It is distressing to witness any animal dying and this rare encounter with Paper Nautilus was no exception. But it was also a privilege as this small encounter offered me a glimpse into the abyss: a reminder of how little we still know about the role of animals in our future.
