This is indeed a very interesting phenomenon!
I've often heard of the saying sleeping with one eye open ... but flying and unconsciously doing an activity when sleeping.... that's amazing.
I didn't know sleep waking had a deep meaning tied to it. I thought it was as a result of stress or just a habit.
I look forward to your post on dolphins and frigate birds.
Thanks for sharing!
RE: The art of staying half-awake: unihemispheric sleep keeps ducks (and humans) safe