Quick & curious · Nature

Octopuses have nerve cells in their arms.

An octopus curled up in its arms
Photo: Victor Micallef · CC BY-SA 4.0 · Original

⅔of the neurons are in the arms

The story behind it

Two-thirds of an octopus's nerve cells are in its arms.

In total an octopus has over 500 million nerve cells – about as many as a dog. Most of them sit not in the head but in the nerve cords of the arms.

Sources

Every statement in this discovery is backed by one of these sources and was checked before publication.

  1. Wikipedia: Octopus (accessed 2026-10-05)

Image credits