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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

#41

Post by semireg »

jcims wrote: post #11
crehn wrote: post #9

Earlier quoted context omitted.

For contrast, ants have around a quarter million neurons.

We have mud dauber wasps around the house. I can't find a good reference for neuron count...the only one I see is for super tiny parasitic wasps which I can't imagine is accurate. Lets assume they are on the order of honey bees at 500k-1M neurons. This past fall I saw one on the ceiling of my front porch. It had a rear leg pinched between the soffit and the edge of a can light. It was pretty obviously struggling, pul…

I know next to nothing about a bug’s life, but interesting to consider distress signals being tuned into otherwise solitary creatures. For colony wasp/bee I could see why distress would bring help (bring more venom!) but solitary… maybe it was kin?

Re: Tardigrades walk like insects 500k times their size

#42

Post by topherhunt87 »

Help me out here:

> the size of tardigrades (which are only about 0.02 inches long)

> the creature's movement resembles that of insects 500,000 times their size

0.02 inches x 500,000 = 10,000 inches or 833 feet. Where does one find insects 800+ feet long? Or rather, how does one stay the heck away from them?

Re: Tardigrades walk like insects 500k times their size

#43

Post by eloff »

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.

There's no reason to believe this is true about the universe, but it is a fun idea to think about. We know so little about consciousness, intelligence, and the brain in general. It is amazing how much insects seem to accomplish with so little.

Re: Tardigrades walk like insects 500k times their size

#44

Post by Joeri »

otabdeveloper4 wrote: post #34
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…

The amoeba has zero neurons, and yet it can hunt prey and can reproduce sexually. Our understanding of intelligence is so laughably primitive that it is "not even wrong".

Makes me think of the classic video of a white blood cell chasing a bacterium. You can sense the frantic desperation of the bacterium as it tries to get away from something monstrous that will inevitably swallow it whole.

https://youtu.be/JnlULOjUhSQ

Re: Tardigrades walk like insects 500k times their size

#45

Post by shard »

topherhunt87 wrote: post #42

Help me out here: > the size of tardigrades (which are only about 0.02 inches long) > the creature's movement resembles that of insects 500,000 times their size 0.02 inches x 500,000 = 10,000 inches or 833 feet. Where does one find insects 800+ feet long? Or rather, how does one stay the heck away from them?

Length is one measure of size, but it may be volume that the title is referring to. So assuming a .02" sphere, 500k times would be about a 1.6" sphere, if my math is correct.

Re: Tardigrades walk like insects 500k times their size

#46

Post by Out_of_Characte »

topherhunt87 wrote: post #42

Help me out here: > the size of tardigrades (which are only about 0.02 inches long) > the creature's movement resembles that of insects 500,000 times their size 0.02 inches x 500,000 = 10,000 inches or 833 feet. Where does one find insects 800+ feet long? Or rather, how does one stay the heck away from them?

They define size as volume or weight rather than length, which makes sense, im 180cm long, an elephant is ~4 meters, making it twice as tall. but its weight can be 6000kg which is a factor of 100 larger than my measely 60kg. Volume grows at ^3 with increase in cubic length.

Re: Tardigrades walk like insects 500k times their size

#47

Post by spaniard89277 »

semireg wrote: post #41
jcims wrote: post #11

Earlier quoted context omitted.

We have mud dauber wasps around the house. I can't find a good reference for neuron count...the only one I see is for super tiny parasitic wasps which I can't imagine is accurate. Lets assume they are on the order of honey bees at 500k-1M neurons. This past fall I saw one on the ceiling of my front porch. It had a rear leg pinched between the soffit and the edge of a can light. It was pretty obviously struggling, pul…

I know next to nothing about a bug’s life, but interesting to consider distress signals being tuned into otherwise solitary creatures. For colony wasp/bee I could see why distress would bring help (bring more venom!) but solitary… maybe it was kin?

But what he explains means there's also some problem solving there. I mean, the coming one grabbed just the ankle that stuck. She didn't pull the other wasp from any other part of her body.

Re: Tardigrades walk like insects 500k times their size

#48

Post by visarga »

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…

> For me it also raises the question of whether they have any subjective experience approximating what we describe as consciousness, or if the entirety of their life is just a long form electro-chemical reaction of deeply nested feedback loops programmed into ~55 million base pairs.

Maybe they are the same thing. Adapting to the environment in order to survive is also the role of consciousness and intelligence in humans. The struggle for life provides a learning framework for the brain, and an intrinsic space of values and emotion, but for each species is different depending on their ecological niche.

I often see people musing about consciousness as something supernatural (a "hard problem" for science), but forgetting to consider the formative role of the environment and the tight coupling of consciousness with goals, which are attainable in the environment. So the macro is being overlooked for the micro.

We can explain much by just looking at the environment-body interaction without the need to identify the pixie dust in the brain. I think consciousness is a process encompassing the interplay between the body and part of the environment, not just the brain. We can't find it in the brain or in the neural net alone, but we can find it in a game of goal maximization of a learning agent. That would include a tardigrade[1].

[1] Aversive conditioning in the tardigrade https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6776688/

Re: Tardigrades walk like insects 500k times their size

#49

Post by mildmotive »

visarga wrote: post #48
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…

> For me it also raises the question of whether they have any subjective experience approximating what we describe as consciousness, or if the entirety of their life is just a long form electro-chemical reaction of deeply nested feedback loops programmed into ~55 million base pairs. Maybe they are the same thing. Adapting to the environment in order to survive is also the role of consciousness and intelligence in hum…

But that still doesn’t explain how we, or other living beings are able to see and feel things from our own perspective. It is genuinely a hard problem, especially if you try to understand it from a purely naturalistic pov.

Re: Tardigrades walk like insects 500k times their size

#50

Post by mjburgess »

otabdeveloper4 wrote: post #34
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…

The amoeba has zero neurons, and yet it can hunt prey and can reproduce sexually. Our understanding of intelligence is so laughably primitive that it is "not even wrong".

I think we're well aware that systems without intelligence can act as-if they have it. It is on this basis humans have been superstitiously imparting souls to any-old-thing for thousands of years.
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