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The Deep Sea

neal.fun

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Re: The Deep Sea

#61

Post by wtracy »

shaki-dora wrote: post #57

Note that “the oldest species of ” doesn’t make any sense. Both that species as well as its closest evolutionary relative have a last common ancestor, meaning they are equally “old”. Do this a few times and you will notice all species have the same “age”, assuming life today all descendent from a common ancestor. Yes, some of them have may have changed more or less in appearance, but that correlates poorly with genet…

"Oldest" in the sense that it has existed (as far as we can measure) in it's current form longer than any other species.

You can't say that a species is as old as it's ancestral species, because you're talking about two different species.

Re: The Deep Sea

#62

Post by pierrec »

alister wrote: post #10

I wonder what prevents a fish that goes down to 100 meters from going down to 300 meters or 3000 meters. Does it feel an internal pressure that tells it to not dive further, or is it the amount of light or availability of food it seeks? Since fish wouldn't suffer from decompression sickness, I wonder if they could dive much deeper if they wanted to. Now that I think about it, I've scuba dived to 130 feet and it didn'…

Your question is a bit vague, but for most fish species, "pressure detection uses the organ of Weber, a system consisting of three appendages of vertebrae transferring changes in shape of the gas bladder to the middle ear." This makes their perception of pressure more direct and granular than ours, so what prevents them from diving deeper could be similar to what prevents us from walking into a fire.

https://en.wikipedia.org/wiki/Sensory_systems_in_fish

Re: The Deep Sea

#63

Post by peripitea »

alister wrote: post #10

I wonder what prevents a fish that goes down to 100 meters from going down to 300 meters or 3000 meters. Does it feel an internal pressure that tells it to not dive further, or is it the amount of light or availability of food it seeks? Since fish wouldn't suffer from decompression sickness, I wonder if they could dive much deeper if they wanted to. Now that I think about it, I've scuba dived to 130 feet and it didn'…

This is because you are artificially pressurized by the air you're breathing when scuba diving that deep. If you held your breath and went that deep, you would definitely feel the pressure.

Re: The Deep Sea

#64

Post by ekianjo »

thaumasiotes wrote: post #51
blotter_paper wrote: post #36

Earlier quoted context omitted.

I can totally imagine wanting to reach it that badly -- what else could you do, turn back that close to the bottom? That said, they didn't actually know that a window had broken until they were already there[0]: > After almost five hours inside their tiny 6ft 4in cabin, the duo touched down on the sea floor at 36,000ft. [...] They spent 20 minutes there identifying the source of the explosive sound – a cracked acryli…

> what else could you do, turn back that close to the bottom? Yes?

You can't come back that fast anyway.

Re: The Deep Sea

#65

Post by matthewhartmans »

Volker-E wrote: post #25

This is beautiful, thanks. Why not linking the creatures to their English Wikipedia pages to get curious folks more background? Wikimedia Foundation employee here in private comment. Just learnt the first time about the Leatherback Sea Turtle here.

+1 for this. Clicking the fish open in a new tab for there Wikipedia page.

Re: The Deep Sea

#66

Post by system2 »

dmitshur wrote: post #56

The content and presentation is fantastic. The page is using up 15-20% CPU and GPU when it is the active tab even when not scrolling. That seems unexpected and unfortunate. (I noticed because by the time I got to 3400 meters, my laptop's fans became audible.)

Same, dell xps13 is on fire. GPU 99%, cpu 30%. Unsure why.

Re: The Deep Sea

#67

Post by remarkEon »

>ELEPHANT SEAL DIVE

>2400 METERS DEEP

That one caught me off guard. I'm used to seeing stories (or "tales") of e.g. Sperm Whales accomplishing incredible dives like that. An elephant seal doesn't really seem to be tuned to that kind of performance dives.

Re: The Deep Sea

#68

Post by madhadron »

clort wrote: post #27
glofish wrote: post #21

Earlier quoted context omitted.

Fish control their buoyancy via a swim bladder. Suddenly bringing up a deep water fish would make it explode. every 33ft up the volume of air doubles. Hence that rule of diving of never holding your breath and continuously letting the air out as you surface. What I find incredible that a seal could dive that deep, the volume of air at that depth would be a tiny fraction of the volume of air at the surface. It is as i…

Yes the lungs are collapsed completely. A seal, as I understand it, has extremely haemoglobin rich blood and stores all its oxygen there for the dive.

For diving mammals, most of the oxygen is carried in the muscles by myoglobin. It turns out that the myoglobin density in muscles is very precisely related with the diving ability of the mammal, and the the density is also very precisely correlated with the surface charge (and thus the exact sequence) of the myoglobin protein. There's an amazing paper about this that then uses myoglobin sequence to infer the diving abilities of extinct mammals.[1]

I'm not in general willing to be a guinea pig for genetic manipulation, but toothed whale myoglobin and being able to dive with empty lungs for half an hour or 45 minutes? Sign me up.

[1]: Mirceta, S., Signore, A. V., Burns, J. M., Cossins, A. R., Campbell, K. L., & Berenbrink, M. (2013). Evolution of mammalian diving capacity traced by myoglobin net surface charge. Science, 340(6138), 1234192–1234192. http://doi.org/10.1126/science.1234192

Re: The Deep Sea

#69

Post by nojvek »

Holy moly. The human diving at 332 meters is insane. That’s 34 ata, or 34 times the atmospheric pressure, or 34x compression on your body. Did they use some sort of inverse pressurized suit that can hold this sort of pressure ? I’ve scuba dived to 50m and even that was a bit dizzy for the brain. People have known to hallucinate if they stay deep too long. 330+ meters is absolute nuts. Wow! Someone explain me the science of how this is possible.

Re: The Deep Sea

#70

Post by wh1t3n01s3 »

herewego wrote: post #43
driverdan wrote: post #42

This looks like it might be cool but it's completely unusable for me in Firefox on a 2012 rMBP. It makes the browser nearly unresponsive, taking about 15 seconds to go back to the previous page.

I’m on an iPhone X on Firefox and it’s a very smooth experience.

My iPhone X on brave got really hot tough
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