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Tardigrades walk like insects 500k times their size

arstechnica.com

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Re: Tardigrades walk like insects 500k times their size

#21

Post by p1mrx »

robbedpeter wrote: post #10
jcims wrote: post #7

With a few minutes of googling the only reference i can find says that Tardigrades have approximately 200 neurons in their brains [1] and their dry weight is on the order of one microgram [2]. They also have a lower count of synaptic connections (from the same paper): >Thus, miniaturisation of the tardigrade nervous system is achieved largely by reducing cell numbers, neuropil branches and the number of synaptic conn…

They seem to occasionally seek the company of other tardigrades, and hug. It could be purely mechanistic stimulus response behavior, but I'd like to think they're experiencing some sort of life, and that it's mostly a good one. That second YouTube video is great!

> They seem to occasionally seek the company of other tardigrades, and hug.

I would assume that this feature is necessary for reproduction.

Re: Tardigrades walk like insects 500k times their size

#22

Post by Razengan »

jcims wrote: post #7

With a few minutes of googling the only reference i can find says that Tardigrades have approximately 200 neurons in their brains [1] and their dry weight is on the order of one microgram [2]. They also have a lower count of synaptic connections (from the same paper): >Thus, miniaturisation of the tardigrade nervous system is achieved largely by reducing cell numbers, neuropil branches and the number of synaptic conn…

What says our consciousness is not just a long form electro-chemical reaction of deeply nested feedback loops programmed into millions of base pairs?

Re: Tardigrades walk like insects 500k times their size

#23

Post by scotty79 »

jbotz wrote: post #8
1024core wrote: post #6

> "Other times, they’d see something they like and run towards it.” Can tardigrades really "see" in the traditional sense? Can they make out shapes, etc.? Do they have photo receptors plugged into the brain?

They can't "really see"... they have eyespots with just a handful of light-sensitive cells and no lenses, so it's just gradients of light and dark. But they have other senses and I think the word "see" was metaphorical here, meaning they sensed the presence of an attractive stimulus. In some ways the real meaning of "see" doesn't depend on optics, you see?

I don't know. They seem to be able to squeeze out a lot of funtionality out of very limited numbers of cells. I wouldn't be surprised if at some point it was discovered that their light sensitive cells slosh around the cytoplasm inside the roughly spherical cell wall turning it into ad-hoc lenses even if for a brief moment. It still might be enough to get light intensity in a specific direction.

Re: Tardigrades walk like insects 500k times their size

#24

Post by clairity »

tiahura wrote: post #4

“The team was surprised to note that the water bears did not have distinct gaits for each speed, like horses as they transition from a walk to a gallop. Rather, their locomotion closely resembled that of insects and arthropods, scurrying along faster and faster with no change to the basic step pattern.” So they expected them to walk like horses and not insects? That seems odd.

what's more odd is that "...locomotion closely resembled that of insects and arthropods, scurrying along faster and faster with no change to the basic step pattern" is completely wrong. many insects and arthropods change gaits/step patterns with speed. it's practically required, as you get beyond optimal energetics pretty quickly (like being stuck in the wrong gear too long on a bike).

cockroaches, for instance, only use their back 4 legs when 'running', and will use only their back 2 legs when all out 'sprinting'. we humans start jogging and then running as speed increases for the same reason, it's not energetically efficient to just 'walk faster'.

Re: Tardigrades walk like insects 500k times their size

#25

Post by nefitty »

Razengan wrote: post #22
jcims wrote: post #7

With a few minutes of googling the only reference i can find says that Tardigrades have approximately 200 neurons in their brains [1] and their dry weight is on the order of one microgram [2]. They also have a lower count of synaptic connections (from the same paper): >Thus, miniaturisation of the tardigrade nervous system is achieved largely by reducing cell numbers, neuropil branches and the number of synaptic conn…

What says our consciousness is not just a long form electro-chemical reaction of deeply nested feedback loops programmed into millions of base pairs?

It is, and it's a very immersive and persistent illusion.

Re: Tardigrades walk like insects 500k times their size

#26

Post by nefitty »

abletonlive wrote: post #19
fleddr wrote: post #16

Earlier quoted context omitted.

I don't know the technical answer to your question but I do think that us humans have continuously underestimated the complexity and intelligence (in the broadest sense) of animals. First, we see them as emotionless objects. Then we acknowledge that some animals seem quite smart, such as dolphins, dogs, pigs and cows, and of course other primates. Then we discover that far more animals have complex systems to communi…

Define "we". Because the smartest people I know are the ones most likely to underestimate as you've described and look down upon people that anthropomorphize. Further, it seems to me that the smartest people I know fall prey to reductionism when it comes to the subject of intelligence or philosophy in general.

It's convenient to clamp our understanding of reality. If I convince myself that cows are baser creatures, it makes it a lot easier to enjoy this juicy burger made from its child.

Re: Tardigrades walk like insects 500k times their size

#27

Post by ddingus »

jcims wrote: post #7

With a few minutes of googling the only reference i can find says that Tardigrades have approximately 200 neurons in their brains [1] and their dry weight is on the order of one microgram [2]. They also have a lower count of synaptic connections (from the same paper): >Thus, miniaturisation of the tardigrade nervous system is achieved largely by reducing cell numbers, neuropil branches and the number of synaptic conn…

Or they are a case for this idea of the universe itself being conscious and beings tap into that via neurological mechanisms we do not understand well.

It may be a base level of complexity / capability is needed to tap into the "field of consciousness", which could explain bees, these things, and other seemingly too small living systems doing more than their apparent weight class would indicate is possible.

Re: Tardigrades walk like insects 500k times their size

#28

Post by jcims »

Razengan wrote: post #22
jcims wrote: post #7

With a few minutes of googling the only reference i can find says that Tardigrades have approximately 200 neurons in their brains [1] and their dry weight is on the order of one microgram [2]. They also have a lower count of synaptic connections (from the same paper): >Thus, miniaturisation of the tardigrade nervous system is achieved largely by reducing cell numbers, neuropil branches and the number of synaptic conn…

What says our consciousness is not just a long form electro-chemical reaction of deeply nested feedback loops programmed into millions of base pairs?

AFAIK that’s the only explanation we have any evidence for at this point.

It’s easy for me to think there’s magic buried in the hundred billion neurons and hundred trillion synapses in the human brain. But in the case of tardigrades or wasps, it becomes much less obvious where the consciousness would ‘live’ with such limited real estate.

Re: Tardigrades walk like insects 500k times their size

#29

Post by moralestapia »

ddingus wrote: post #27
jcims wrote: post #7

With a few minutes of googling the only reference i can find says that Tardigrades have approximately 200 neurons in their brains [1] and their dry weight is on the order of one microgram [2]. They also have a lower count of synaptic connections (from the same paper): >Thus, miniaturisation of the tardigrade nervous system is achieved largely by reducing cell numbers, neuropil branches and the number of synaptic conn…

Or they are a case for this idea of the universe itself being conscious and beings tap into that via neurological mechanisms we do not understand well. It may be a base level of complexity / capability is needed to tap into the "field of consciousness", which could explain bees, these things, and other seemingly too small living systems doing more than their apparent weight class would indicate is possible.

Do you have some resources you'd like to share around this? Would love to read about it.

Re: Tardigrades walk like insects 500k times their size

#30

Post by ddingus »

moralestapia wrote: post #29
ddingus wrote: post #27

Earlier quoted context omitted.

Or they are a case for this idea of the universe itself being conscious and beings tap into that via neurological mechanisms we do not understand well. It may be a base level of complexity / capability is needed to tap into the "field of consciousness", which could explain bees, these things, and other seemingly too small living systems doing more than their apparent weight class would indicate is possible.

Do you have some resources you'd like to share around this? Would love to read about it.

https://www.nbcnews.com/mach/science/universe-conscious-ncna...

I have seen this idea pop up a few times and find it intriguing. I have read much better, but struggle to find links right now.

That said, this backgrounder / brief type piece should point you to the rabbit hole.

To me, in the most general sense, it's similar to the idea of the universe being cyclic, rather than having some definitive beginning and or end. It may just always be.

In this context, consciousness may be an emergent artifact of how living systems function, or maybe it's a thing of it's own, or... Who knows? I don't, but I consider basic branches of thought like this important, if nothing else to stimulate possible lines of thought easily passed by otherwise.

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