Page "Nautilus" Paragraph 19

In a study in 2008, a group of nautiluses ( N. pompilius ) were given food as a bright blue light flashed until they began to associate the light with food, extending their tentacles every time the blue light was flashed.

The blue light was again flashed without the food 3 minutes, 30 minutes, 1 hour, 6 hours, 12 hours, and 24 hours later.

The nautiluses continued to respond excitedly to the blue light for up to 30 minutes after the experiment.

An hour later they showed no reaction to the blue light.

However, between 6 and 12 hours after the training, they again responded to the blue light, but more tentatively.

The researchers concluded that nautiluses had memory capabilities similar to the " short-term " and " long-term memories " of the more advanced cephalopods, despite having different brain structures.

However the long-term memory capability of nautiluses was much shorter than that of other cephalopods.

The nautiluses completely forgot the earlier training 24 hours later, in contrast to octopuses, for example, which can remember conditioning for weeks afterwards.

However, this may simply be the result of the conditioning procedure being suboptimal for sustaining long-term memories in nautiluses.

Nevertheless the study showed that scientists had previously underestimated the memory capabilities of nautiluses.