Sperm Whales Blow Bubbles to Achieve Restful, Vertical Sleep
Our research reveals that sperm whales release gas bubbles to regulate buoyancy, allowing them to sleep vertically just below the ocean surface. This unique behavior counteracts their natural positive buoyancy from spermaceti oil and prevents drifting upward due to expanding lung gas. By analyzing tag data from the Norwegian coast, we confirmed these fine-scale adjustments enable restful sleep while submerged, a feat alien to terrestrial mammals.
This study confirms that Sperm Whales exquisitely control their buoyancy by releasing gases to remain submerged with near-neutral buoyancy just below the sea surface. It is particularly fascinating they are able to make these fine-scale adjustments while they are thought to be asleep, a challenge totally alien to terrestrial mammals like us humans.
- dguest
The title of the original article [1] is a lot more clear:
Buoyancy regulation through modulation of onboard gas volume by resting sperm whales
They don't "blow bubbles" to sleep vertically, they vent gas to regulate their specific gravity. This allows them to sleep vertically below the surface. The scientists measured the gas release by listening for bubbles, but they did a lot more: they actually modeled the buoyancy of whales and compared it with data.
If you've done any scuba diving (or swimming) you're familiar with this method of buoyancy control. And most fish accomplish on actively transporting gas between an internal bladder and their blood.
The difference is that whales have no way to refill their lungs while submerged, which is why their dives start deep and slowly drift up: as long as they are drifting upward the volume in their lungs is expanding in response to decreasing pressure. So the bubbles are essentially a way of pumping the breaks, which is apparently something they can do in their sleep (if they are in fact sleeping).
Is anyone else slightly annoyed by the cutesy title? Of course I recognize that the meme economy runs on this stuff, so maybe it's just nerds like me.
[1]: https://dmscdn.vuelio.co.uk/publicitem/61eae467-9527-4922-b9...
- kazinator
If these are rainbow bubbles, that conclusively proves the whales had ADHD therapy sessions.
- giardini
What happens if they have an attack of flatulence?
But seriously, this must happen sometimes!