The topic of octopus spiked last year for various reasons, but we have been interested in these creatures for much longer. Thanks to Benjamin Thompson and Shamini Bundell for this podcast on Nature’s website:

Do octopuses dream? Neural activity resembles human sleep stages

Brain probes reveal complexities of octopus sleep, and a hormone that could help make calorie-restricted diets more effective.

00:46 Inside the brains of sleeping octopuses

Researchers have probed the brains of octopuses and confirmed previous reports suggesting that these invertebrates have a two-stage sleep cycle similar to that seen in many vertebrates. The team suggests this system may have evolved independently in the two groups, as there are millions of years of evolutionary history between them. However, despite its presumed importance, it is a mystery why this system exists at all.

Research article: Pophale et al.

Nature Video: Do octopuses dream? Brain recordings provide the first clues