How smart are cuttlefish?

Pretty damn smart! In fact, they are among the cleverest invertebrates known to science. As well as being capable of solving mazes and puzzles, they’re able to plan and even retain their mental sharpness as they age.

For example, research published in Proceedings of the Royal Society B: Biological Sciences in 2021 found that memory in cuttlefish does not decline with age, unlike in humans.

“Cuttlefish can remember what they ate, where and when, and use this to guide their feeding decisions in the future. What’s surprising is that they don’t lose this ability with age, despite showing other signs of ageing like loss of muscle function and appetite,” said Dr Alexandra Schnell, first author of the paper.

Read more about cephalopods:

• Octopuses have sleep stages like humans, and may even dream 
• How do squid survive extreme water pressure in the deep sea?
• Scientists give cuttlefish 3D glasses to test their eyesight

In another study, researchers found that cuttlefish have self-control. When presented with the option of eating a raw king prawn immediately or a grass shrimp (their preferred food) after a short delay, the marine molluscs chose the latter option. This demonstrates that cuttlefish can delay gratification in a similar way to large-brained vertebrates like chimpanzees. It’s the first time this behaviour has been seen in an invertebrate.

“The ability to exert self-control is an important element of the ability to plan for the future, which is quite a sophisticated behaviour,” said Prof Nicola Clayton, senior author of the report.

“Self-control requires an understanding that ‘less is sometimes more’ – that avoiding temptation now might lead to a better future outcome. This is a critically important building block for the evolution of complex decision-making.”

Cephalopods are thought to be the smartest invertebrates, thanks to their large brain-to-body mass ratio and complex nervous system, and they could help us to understand the evolution of intelligence throughout the animal kingdom.

One theory regarding why cephalopods evolved to be so intelligent is that the loss of their shells made them more vulnerable to predators, so they had to learn how to hide and exploit challenging niches.

What do cuttlefish eat?

Cuttlefish are fast, intelligent predators with excellent eyesight, which allows them to hunt for crustaceans such as shrimp and crabs. They use their impressive camouflage to sneak up on the prey, then shoot out their two feeding tentacles to grab the unfortunate animal, before munching it up with their sharp beak.

How many tentacles do cuttlefish have?

Just two. The other eight appendages are arms. The two tentacles are longer, with a widened area on the end with a cluster of suckers – these are used for grabbing and gripping prey. The arms have suckers all the way along them. The suckers may even allow the cuttlefish to taste the water and the substrate, so they can gain information about their surroundings.

How do cuttlefish change colour?

The ability of a cuttlefish to instantly transform the colour, reflectiveness and texture of their body is truly remarkable; chameleons should hang their heads in shame. They use their colours to communicate, to scare off predators and for camouflage.