" Octopuses love to eat crabs. But in the lab they're often fed on thawed out frozen shrimp or squid. It takes octopuses awhile to get used to these second-rate foods, but eventually they do.

One day Boyle was walking down a row of tanks feeding each octopus a piece of thawed squid as she passed. On reaching the end of the row she walked back the way she had come. The octopus in the first tank, though, seem to be waiting for her. It had not eaten its squid but instead was holding it conspicuously. As Boyle stood there, the octopus made its way slowly across the tank towards the outflow pipe, watching her all the way. When it reached the outflow pipe, still watching her, it dumped the scrap of squid down the drain. "

― Peter Godfrey-Smith , Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness