Pavlov’s amoebas: They may not have brains, but they have memory

#1
https://www.haaretz.com/science-and-heal...-1.7872066

EXCERPT: Trained dogs will salivate at the sound of a dinner bell, Ivan Pavlov famously discovered by accident in the 1890s. If the dogs realize that a peal portends food, they will drool at its sound and not only when the meal materializes. That is called conditioning. Now, a multidisciplinary group of Israeli and Spanish scientists found evidence that amoebas can be conditioned too — which was quite the shocker given that they are one-celled animals with no brain.

... What they [the amoebas] were doing is remembering the way to food for up to 90 minutes, report ... Shira Knafo of Ben-Gurion University ... and others, with disciplines encompassing mathematics, cancer research and pathology. Their groundbreaking study was published in the journal Nature.

... Amoebas have never been suspected of smarts. Nor are they now. Knafo and her colleagues suspect the associative memory of the avenue to food is biochemical: temporarily encoded in a network of proteins. Associative memory — the ability to learn and remember a consistent relationship between unrelated things, such as a sound and steak — was thought to be the prerogative of animals that have nervous systems. ... It has not been demonstrated in unicellular species, until now.

... The experiment was repeated with another one-celled animal, Metamoeba leningradensis, a cousin to the simple amoebas we know and love. The same results ensued. Now the team is working on four more amoeba species, Knafo told Haaretz. Since this “memory of how to find food” has now been found in two amoeba species, one may suspect that it’s universal. However, it is early days and, yes, the team does plan, generally, to test for the phenomenon in other unicellular species before seriously postulating its universality. (MORE - details)
Reply
#2
I like the way some of the little critters seem to have a mind of their own and don't follow the pack. All credit to the researchers for not snopaking them out. 'Mind'=brain?
Reply
#3
(Sep 25, 2019 11:16 PM)confused2 Wrote: I like the way some of the little critters seem to have a mind of their own and don't follow the pack. All credit to the researchers for not snopaking them out. 'Mind'=brain?

If the amoeba did not like the food given and ignored it altogether, would we know if it was from memory? Obviously one has to taste something first but the memory of  a bad taste kind of lingers. Is avoidance the result of memory in the animal kingdom? I think this study may provide an example of an earlier stage of memory evolution. Don't need all 5 senses in the amoeba's case....at least I don't think so.

Animals born with danger markings or warnings to predators are IMHO other examples of memory jogging. In the case where a bird for example, devours a Monarch butterfly, not a pleasant meal, does it register in the bird's mind to stay clear and can a parent bird teach their brood to avoid simply by avoiding....either way both from memory, parent & fledgling? Seems the amoeba from what I've read, has not reached the teaching stage but it would be interesting to see if they could pass on knowledge to a another based on primitive memory.
Reply
#4
(Sep 25, 2019 11:16 PM)confused2 Wrote: I like the way some of the little critters seem to have a mind of their own and don't follow the pack. All credit to the researchers for not snopaking them out. 'Mind'=brain?

We're still brain chauvinistic to some extent. The possibility of strong AI and ETI mandate that "mind" is a generic category that could subsume a variety of ways that cognitive systems are concretely instantiated. Fred Hoyle's Black Cloud concept which Freeman Dyson's "analog life-form" revolves around would be an extreme example.

The bare "stored information" aspect of memory is pretty much ubiquitous. Oscillating mediums carry such as long as they persist. Paleontologists, archeologists, geologists, and forensic scientists demonstrate that all manner of objects/substances and the surrounding conditions they're embedded in harbor "records" or knowledge-related patterns that retain the past.

Such storage being recruited, processed or utilized in a constructive way is another matter, reflexively associated with cognitive ability or some degree of proto-intelligence organization.

But the coding and encoding chemical apparatus in cells that uses polymers to store and retrieve a "blueprint" for their host organisms at least establishes a memory system that's elemental and robotic-like. Thus, standing in the shadow of something like that which precedes the higher-level intricacies... Whatever "recall" feats single celled organisms may exhibit after that necessity for their existence shouldn't be in science fiction territory due to a missing nervous system or brain.

(Sep 26, 2019 03:01 PM)Zinjanthropos Wrote: If the amoeba did not like the food given and ignored it altogether, would we know if it was from memory? Obviously one has to taste something first but the memory of  a bad taste kind of lingers. Is avoidance the result of memory in the animal kingdom? I think this study may provide an example of an earlier stage of memory evolution. Don't need all 5 senses in the amoeba's case....at least I don't think so.

Animals born with danger markings or warnings to predators are IMHO other examples of memory jogging. In the case where a bird for example, devours a Monarch butterfly, not a pleasant meal, does it register in the bird's mind to stay clear and can a parent bird teach their brood to avoid simply by avoiding....either way both from memory, parent & fledgling? Seems the amoeba from what I've read, has not reached the teaching stage but it would be interesting to see if they could pass on knowledge to a another based on primitive memory.


Amoebas, of course, are more complex than bacteria, so one wonders all the more about their capacities. Bacteria can chemically sense and react to their environment and even "feel it". They can pass on memory to descendants.

While single cells can have their "senses", in terms of science dogma they don't have literal feelings or experiences of "taste" since that would be in the direction of panpsychism, which most scientists abhor. They want manifestations to be associated with vast tissue areas rather than at the level of individual chemical interactions or small sets of processes.

In a way, perhaps it's ironic that so much is attributed to the microscopic, but not vegetation. There's controversy over plant memory, which due to the pervasiveness of pattern retention is far less crazy than the rogue orientation which claims plants can outright think. If Monica Gagliano confines herself to that and treating some sluggish flora responses as a precursor type of environmental detection and "learning", it drops a step from far-farfetched.

Big Think: While “behavior" may seem an odd word to use, the undisputed fact is that plants do respond to stimuli, albeit often very slowly over the course of hours, days, or weeks. This makes it easy to feel like nothing is going on with them. Still, as Michael Pollan points out, “A race of aliens living in a radically sped-up dimension of time arrive on Earth and, unable to detect any movement in humans, come to the logical conclusion that we are “inert material" with which they may do as they please. The aliens proceed ruthlessly to exploit us."

Plants do, however, sometimes move in a time frame we can perceive, as in Gagliano's controversial study of Mimosa pudica — or “touch-me-not" — a plant whose leaves fold when touched or disturbed, the assumption being that it's the plant's response to insects that might pose a threat.
Reply
#5
CC Wrote:We're still brain chauvinistic to some extent.
(checked - yes it was posted by CC)
Hamsters. A hypothetical test for a hamster would be to place a block in the middle of a box. If the hamster moves the block to the side of the box it will be able to reach (or jump) to the top of the box and escape. I don't think most hamsters are smart enough to immediately move the block to the side of the box to escape. But. If you leave the hamster for a few hours you will find the block moved to the side of the box and no hamster in the box. The strategy isn't to think "Will moving the block be helpful?" the strategy is to apparently randomly move the block until (sort of) by chance the block is in the right place to escape. A hamster will devote time to any activity that it thinks might lead to escape in rough proportion to how likely it thinks the activity will lead to escape. Moving the block might initially seem low probability but once the block has been moved and been jumped off (apparently randomly) it will upgrade 'moving the block' from 'why not?' to 'increase time allocated to moving the block'. The 'increase time allocated to moving the block' isn't the same as 'move the block to the side of the box' . After many apparently random actions the block will end up at the side of the box and the hamster will escape. At this point I will say that hamsters (like amoeba) are all individuals - I think one of my hamsters would have moved the block to the side of the box to the best point to jump from without going through any random movements. The point (my point) is that the usual hamster strategy works even though it takes more time than figuring the actual reason for moving the block. The apparently random strategy might uncover means that would be missed by a more 'intelligent' strategy - for example there may be a possibility of tunneling out through some weak point in the bottom of the box - a hamster will certainly devote time to that.
Reply
#6
Where was I? Yes. Hamsters. The point is - a hamster has predictable behaviour but not the same behaviou all the time. Likewise all amoebe should be sucked into voltage gradioent but some will randomly have that behaviour turned off or reversed for some of the time and will escape. Pure random can look smart and indeed is smart. My hypothesis is that (probably) all lifeforms have an element of random (possibly timed) behaviours so they don't all end up in the same cooking pot.
Reply
#7
(Sep 28, 2019 11:58 AM)confused2 Wrote: Where was I? Yes. Hamsters. The point is - a hamster has predictable behaviour but not the same behaviou all the time. Likewise all amoebe should be sucked into voltage gradioent  but some will randomly have that behaviour turned off or reversed for some of the time and will escape.  Pure random can look smart  and indeed is smart. My hypothesis is that (probably) all lifeforms have an element of random (possibly timed) behaviours so they don't all end up in the same cooking pot.

Sort of like two boxed hamsters, one randomly moves the block and escapes while the other stays put, yet neither knew their box was surrounded by cats. One we would call smart, which one?
Reply
#8
(Sep 28, 2019 11:58 AM)confused2 Wrote: Pure random can look smart  and indeed is smart. My hypothesis is that (probably) all lifeforms have an element of random (possibly timed) behaviours so they don't all end up in the same cooking pot.

Yeah, you’re probably right.

"Knafo and her colleagues suspect the associative memory of the avenue to food is biochemical: temporarily encoded in a network of proteins."

If there is no chemoattractant present, all moving cells navigate in random directions, allowing them to search for new extracellular signaling molecules. 

EGF for one, increases motility. EGF is secreted by stromal cells. Tumor cells secrete factors that attract stromal cells, which enhance migration and survival of the tumor cells. This loop increases the mobility of cancer cells. It allows them to move from the collective and begin an individual invasion.

Cells are good at adapting to the environment. Some recent research suggest that you can’t teach an old dog new tricks, meaning that memory makes them less adaptable. A few studies are showing that cancer cells might delete their memory of their past environment in order to adapt to their new environment.

Further reading:

Cancer-suppressing protein is part of amoeba's compass



(Sep 28, 2019 12:23 PM)Zinjanthropos Wrote: Sort of like two boxed hamsters, one randomly moves the block and escapes while the other stays put, yet neither knew their box was surrounded by cats. One we would call smart, which one?

If it's a male and female, I'd say the one that escapes because density also leads to extinction.

Interestingly, though, contact inhibition is a key anticancer mechanism that arrests cell division when cells reach a high density. Tumor suppressor proteins play an important role.

Naked mole-rats are fascinating because they almost never get cancer. Their cells are hypersensitive due to early contact inhibition though two tumor suppressors, P16 and P27. These are thought to be a double edge sword. They protect against cancer but increase cellular senescence. Odd, though, because naked mole rats don’t die of old age.
Reply
#9
Quote:If it's a male and female, I'd say the one that escapes because density also leads to extinction. 


Too bad escapee won't  be around to pass on the smarts. OTOH the surviving hamster, the one who stayed put and avoided the cats is at the very least, smart by default.

Do we label all survivors as being smart? Pretty hard to put that label on something that dies before it grows old even if demise is only by chance or bad decision. Although the escaping hamster probably deserves the label more than the other one, well you know what happens when hamsters meet cats.

Smartness and dumbness ends at inevitable death so perhaps a critter able to prolong its life is the smart one.
Reply
#10
SS Wrote:"Knafo and her colleagues suspect the associative memory of the avenue to food is biochemical: temporarily encoded in a network of proteins."
Imagine you (we) dogs and amoeba have a set of coloured pegs which we can attach to a piece of string.
For a dog -
green peg =recognise bell sound
blue peg=get ready to eat
If the bell and food tend to happen at the same time then the dog puts a blue peg (ready for food) next to the green peg (recognise bell sound). Neither action is difficult for a dog - nor is putting the blue peg and the green peg next to each other. So the dog is continually looping through (possibly many) strings dealing with the pegs that are next to each other - learnt behaviour.

An amoeba just needs to have some sort of string (possibly just one) and pegs (existing behaviours) and to be able to put one next to the other to 'learn'. Deliberately (or accidentally) skipping a few pegs gives the observed variation of behaviour. Given the sophistication (and internal organisation) required to move using pseudopodia it is no great stretch to credit them with an extra small step of having a string with pegs in it.

Going back to hamsters (for no reason except I have spent many happy hours with hamsters):-
My hamsters have always been 'trained' to respond to the word Hamster. In fact, in the give and take between sentient beings, it may be that they trained me to avoid using the word 'Hamster' unless I had something to offer. So after calling a sleeping hamster they would add their own pegs of purely hamster behaviour to the routine. A delay of their choosing. Emerge from the nest. Stretch. Yawn. Pee in the jamjar provided for the purpose. Wash. And then finally address the reason why they have been summoned. Given that for me a hamster emerging from its nest is like the Sun coming out I would never abuse the trust between myself and a hamster. Training is for animals. Trust is for family.
Reply




Users browsing this thread: 1 Guest(s)