Could a benthic, ocean floor culture develop metallurgy by employing volcanism?

[SkepticJ]

If the NTIs have access to waxes or resins, they could create water-excluding vessels without ceramics or glass.

I’m not sure that it’s very likely that they would have access to them, though. Biogenic waxes and resins are, to my understanding, evolved (in plants) to prevent water loss, which obviously isn’t a problem that exists underwater. Bees use their wax to create containers that honey can’t soak into (if it wasn’t for the honey, bees would probably just make their larva cells out of paper or mud like wasps).

Does any known living thing that lives exclusively underwater produce waxes or resins?

[Roger E. Moore]

One problem regarding life forms in subsurface oceans (Europa type) is that we don't know what pressures exist under the ice cap, from open waters down to the solid sea floor. This would be a problem for life form design.

In addition, vision would be a problem. A creature might have infrared vision near volcanic areas, or a less sensitive/focused sound "vision" like sonar. You have to see what you are working with.

[Roger E. Moore]

For that matter, could a subsurface ocean on a non-molten world (one not like Io) have heat vents or volcanism that would help out benthic life?

[Roger E. Moore]

And are there any possibilities you can imagine in which a pelagic, or open ocean, culture could become a civilization?

Intelligent species that do not walk, only swim?

Dolphins, whales, etc. are considered intelligent, but a civilization of them... "a relatively high level of cultural and technological development "... cultural yes, with fish herding and recording of migrations, adventures, but technical, not so much.

[Noclevername]

Intelligent species that do not walk, only swim?

Dolphins, whales, etc. are considered intelligent, but a civilization of them... "a relatively high level of cultural and technological development "... cultural yes, with fish herding and recording of migrations, adventures, but technical, not so much.

There are mid-ocean cephalopods, so maybe handling tools is not out of the question. What they'd use for tools, however, is a mystery. Fish bones?

[Roger E. Moore]

So far as we know, the first tools/weapons employed by humans were rocks. We got picky about the kinds of rocks we wanted, though. Perhaps the first tools employed by an ocean flood culture would be stones or animal bones.

Perhaps it would be easier for deep ocean-floor life to appear and evolve if they have the equivalent of whale falls to scavenge.

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

[Noclevername]

So far as we know, the first tools/weapons employed by humans were rocks. We got picky about the kinds of rocks we wanted, though. Perhaps the first tools employed by an ocean flood culture would be stones or animal bones.

Perhaps it would be easier for deep ocean-floor life to appear and evolve if they have the equivalent of whale falls to scavenge.

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

But in the case of fully pelagic species, the sea floor may be deep out of reach, cut off by pressure differential.

[SkepticJ]

In addition, vision would be a problem. A creature might have infrared vision near volcanic areas, or a less sensitive/focused sound "vision" like sonar. You have to see what you are working with.

Bioluminescence is an option. There are predatory abyssal fish that use bioluminescent “flashlights” to illuminate their prey. With sensitive enough eyes, it doesn’t take much light to see.

[Noclevername]

Bioluminescence is an option. There are predatory abyssal fish that use bioluminescent “flashlights” to illuminate their prey. With sensitive enough eyes, it doesn’t take much light to see.

/

But in a world without sunlight to encourage the evolution of eyes, would such luminescence even be a thing?

[SkepticJ]

But in a world without sunlight to encourage the evolution of eyes, would such luminescence even be a thing?

That’s a very good point.

I’ve thought about it, and maybe? It would require that an individual organism simultaneously have the mutations that enable primitive bioluminescence and light detection. Statistically, this would take a looooong time to happen in a macroscopic creature, but it wouldn’t take one.

Euglena, single-celled organisms, can see light—it’s useful to them because they’re autotrophs. They swim to the light. Picture a heterotrophic “euglena” that emits light, and swims towards what reflects a little bit of that light back. That’s how it locates potential food.

From there, you could eventually get macroscopic creatures with camera-eyes. Just give it half a billion years.

[SkepticJ]

A creature might have infrared vision near volcanic areas . . .

Unfortunately, no, this isn’t possible. Water is opaque to thermal infrared. Near infrared (used in some night vision cameras) is an option, if you can find a source for that form of light. A bit of googling shows that near infrared bioluminescence is known to be possible.

[Roger E. Moore]

Unfortunately, no, this isn’t possible. Water is opaque to thermal infrared. Near infrared (used in some night vision cameras) is an option, if you can find a source for that form of light. A bit of googling shows that near infrared bioluminescence is known to be possible.

Dang, forgot that, my bad. Thank you for the fix. This did make me think more about underwater vision, and how living things could enhance it. I'm inclined to think that sound and pressure detection would augment sight a great deal.

How would this affect the development of intelligence, though? Now I'm wondering.

[Roger E. Moore]

This being a "hypothetical thought experiment" thread and all, we haven't talked a lot about the sort of alien who would use tools and attempt metallurgy on the sea floor.

My vote is for a long-limbed spider-crab thinger (see illo). The limbs keep the central body/head away from danger (some limbs could aim upward for defense), it could have 2-4 manipulative limbs, it can walk/ jump/ climb/ pole vault.

Not sure what pressure it could withstand, but in shallow seas it would be fine.

Any other suggestions for physiology or shape?

[Jens]

Not sure what pressure it could withstand, but in shallow seas it would be fine.

Any other suggestions for physiology or shape?

I could be wrong about this, but I always assumed that as long as a creature was born under a certain pressure, the pressure wouldn't matter because the pressure inside and outside its body would be the same. So that a creature born in the deep can have any shape, but if it goes upwards it will have problems.

[Noclevername]

I could be wrong about this, but I always assumed that as long as a creature was born under a certain pressure, the pressure wouldn't matter because the pressure inside and outside its body would be the same. So that a creature born in the deep can have any shape, but if it goes upwards it will have problems.

As it rises, its shape approaches spherical, then becomes ...many small shapes.

[Tom Mazanec]

I read somewhere that vision can only go slightly into infrared, IIRC because at liquid water temperatures the retina is overstimulated.

[publiusr]

This being a "hypothetical thought experiment" thread and all, we haven't talked a lot about the sort of alien who would use tools and attempt metallurgy on the sea floor.

My vote is for a long-limbed spider-crab thinger?

Best not to send an astronaut diver to make contact.
https://www.youtube.com/watch?v=XytVHT5GnWQ

[Noclevername]

I read somewhere that vision can only go slightly into infrared, IIRC because at liquid water temperatures the retina is overstimulated.

Among eyes with retinas, yes. IIRC, arthropod compound eyes have less limitations. Mosquitos, in particular.

[Barabino]

How would they get close enough to the molten materials to make tools out of them?

meh, yes. it's like dreaming of using a tornado to dry one's hair...

[Barabino]

for a man like me that used to spend his youth swimming in the sea being lazy on the beach , Aquaman is as disgusting as a "sewage man" for you people who grew up in a big city

[Barabino]

although what these hypothetical undersea civilisations might do with gold is another matter.

H.P. Lovecraft spoke passionately of the barbaric jewels of pre-human civilizations (some of them flourishing in Anctartica)



—the lavas that restlessly roll
Their sulphurous currents down Yaanek
In the ultimate climes of the pole—
That groan as they roll down Mount Yaanek
In the realms of the boreal pole

[Barabino]

he spoke about that in the Shadow over Innsmouth story:

http://www.hplovecraft.com/writings/...ction/soi.aspx

it brought in references to strange jewels clearly akin to the malign tiara I had seen at Newburyport. Perhaps the ornaments had, after all, come from some strange island; and possibly the wild stories were lies of the bygone Obed himself rather than of this antique topic.