sperm whales napping

[Paul Pless]

they gather in a group
take several deep breaths
then fall down in the water column fifty to one hundred feet
and sleep vertically for about two hours at a time

[Andrew Craig-Bennett]

It is an evolutionary adaptation to humans developing ships. Whales that sleep on the surface get run into by ships.

[George.]

Sounds likely, Andrew.

[wizbang 13]

It is an evolutionary adaptation to humans developing ships. Whales that sleep on the surface get run into by ships.

you recon they slept on the surface a few hundred years ago?

[WszystekPoTrochu]

They still do sleep on the surface, part of the time:

https://www.nature.com/news/2008/080...s.2008.613.mov

They surface to take a breath, while still asleep. They will not sink ASAP. They also have no strong preference of chosen depth that would indicate avoiding ships.
Also, like many cetaceans, sperm whales are thought to sleep with half of their brain at the time. Unlike other cetaceans, we think that they do fall in full sleep for some short periods. They spend some of this vertical position in "true" sleep.

[The Ranger]

Podcast?

[Andrew Craig-Bennett]

I wasn’t being serious!

I have the idea that the hippopotamus is related to cetaceans.

[L.W. Baxter]

i imagine that depth and posture has to do with achieving effortless neutral buoyancy.

in other words, they don't chose that depth or vertical position. with lungs full of air and no fin flapping, that is where they end up.

[David W Pratt]

Is it evolutionary, or a learned behavior? Granted a learned behavior can be passed down generations, but that's more a sort of pseudo Lamarckism than evolution.

[Ralphie Boy]

They are incredible creatures.

Saw a Blue whale and her calf close up once near Dana Point. At one point the whale spouted and the spray blew in my face; it was one of the highlights of my life.

[Hugh MacD]

They are incredible creatures.

Saw a Blue whale and her calf close up once near Dana Point. At one point the whale spouted and the spray blew in my face; it was one of the highlights of my life.

HA! Whaleatosis We were doing the Bridge-to-Bridge (Astoria to Newport, Or) one year in a drifter and drifted past a sleeping whale. When we got downwind we were all surreptitiously checking armpits, going, "is that me?".

[Osborne Russell]

Tired of adapting to homo sapiens.

[George.]

i imagine that depth and posture has to do with achieving effortless neutral buoyancy.

in other words, they don't chose that depth or vertical position. with lungs full of air and no fin flapping, that is where they end up.

It wouldn't work. As they sink the increasing pressure compresses their lungs so they become less buoyant. They would have to push themselves down to that depth deliberately and then exhale until they are neutrally buoyant.

[David W Pratt]

It wouldn't work. As they sink the increasing pressure compresses their lungs so they become less buoyant. They would have to push themselves down to that depth deliberately and then exhale until they are neutrally buoyant.

Like the little Cartesian divers we used to get with toothbrushes.

[L.W. Baxter]

It wouldn't work. As they sink the increasing pressure compresses their lungs so they become less buoyant. They would have to push themselves down to that depth deliberately and then exhale until they are neutrally buoyant.

could be i am wrong.

but, likely that on the surface, with full lungs, they are positively buoyant. so, if they fill their lungs to less than capacity, they would sink until the air in their lungs made them neutrally buouyant again. expelling air slowly while napping would cause them to sink slowly until, past a certain depth, the air in their lungs would be compressed to make them negatively buoyant, and they would sink to the bottom without further exhalation.

but, it is possible to attain neutral buoyancy at a given depth with a given amount of air in a bladder, or in one's lungs.

that is the principal of buoyancy as i remember it from scuba.

[Paul Pless]

no doubt you have better more accurate sources than i
mine info came from a porn site
a boat porn site