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

[Zinjanthropos]

I still think remembering/learning what to avoid is just as equally important, if not more. In a predatory world it is not unusual for a prey organism to avoid what is for them, a pleasurable or life sustaining experience. Take your local watering hole in the savannah, as much as an animal wants or needs to have a drink it is mega important to remember why, for whatever the reason, it can’t just walk up and slake its thirst.

At the golf course I belong to are two Border Collies that will follow you around as you play. They play hide and seek, climb on your golf cart and rest upon it in the shade and do the same in the shadow of the cart. I associate these behaviours as something the dog has learned and finds pleasurable. However the dogs belong to homeowner next to course and there are occasions when the dogs will not run onto the course. Why? Because the electric underground dog fence is activated. Well, let's just say take it from there.

I’d like to see the scientists in the amoeba memory study introduce an appreciative predator around the same snack, even just surround it with something unpalatable, and then see what happens. Will the amoeba still go willy-nilly to the food if they are going to run the risk? If they don’t, have they remembered not to? I guess my question to them would be...how do scientists distinguish between between avoid and confront, and why would both scenarios be different in the case of memory?

Avoidance is memory driven IMHO. Perhaps we simply don’t recognize avoidance as memory. Maybe because we’re top predator and very adaptive.idk. Look what could happen if you don't look both ways before crossing the street as an example. If you don’t remember to do it then you run the risk. Would we say a person who looked both ways actually remembered? It’s a learned behaviour isn’t it? Two things an animal has to remember in order to stay alive .....eat and avoid being eaten, just saying.

[confused2]

Avoidance is memory driven IMHO.

This kind of assumes the victim (or part of the victim) survives an attack and has enough sensory apparatus to work out what it was that did the attacking. I'm not sure amoeba are likely to either survive an attack or have the apparatus to work out what went wrong even if they did survive an attack. My guess would be that avoidance strategy (if any) relies on one amoeba releasing chemicals when its membrane is ruptured to suggest to its fellows in the area that it is time to hide/run like the wind.

[Zinjanthropos]

Yep, you have to be alive in order to avoid unless of course you’re bent on avoiding life. Death is worse case scenario for non-avoiders, can’t argue with that. However I don’t think predators have a 100% success rate....Ok,ok I’m just messing with ya. Perhaps a physical trait helps one avoid death from an attacker, regardless I don’t think it wise to go back in there and give it another shot. Wise, meaning you’ve remembered.

Like your tales from the hamster cage. How’s the seagull situation?

[Secular Sanity]

I’d like to see the scientists in the amoeba memory study introduce an appreciative predator around the same snack, even just surround it with something unpalatable,  and then see what happens. Will the amoeba still go willy-nilly to the food if they are going to run the risk? If they don’t, have they remembered not to? I guess my question to them would be...how do scientists distinguish between between avoid and confront, and why would both scenarios be different in the case of memory?

Avoidance is memory driven IMHO.  Perhaps we simply don’t recognize avoidance as memory. Maybe because we’re top predator and very adaptive.idk. Look what could happen if you 

Um...they did, Zinman.

Did you read the article?

[Zinjanthropos]

I did but I likened the positive charge to an obstacle, not a threat nor did it change the food. Even at the water hole, eventually you just gotta go and get a drink. Did they starve the amoeba?

[Secular Sanity]

I did but I likened the positive charge to an obstacle, not a threat nor did it change the food. Even at the water hole, eventually you just gotta go and get a drink. Did they starve the amoeba?

You did say even just surround it with something unpalatable and they did showed a repulsion for that charge.

The anode is where chemicals lose electrons and the cathode is where they gain them. 

When you read about the reactions of amoeba to electricity, it does makes you wonder about the strength of the current, though. Some previous studies show that in a strong current, the entire plasmasol stops flowing and then reverses in direction, resulting in complete reversal in direction of movement of the organism.

They assume that the accumulation of positive ions increases the porosity of the plasmagel, since water passes or is forced through it and collects under the plasmalemma, forming a clear blister; that either the continued action of cations or this passage of water so the weakens the plasmagel that it finally breaks down completely, forming a pseudopod which extends toward the cathode; and that the accumulation of negative ions within the plasmagel on the side toward the anode decreases porosity of the plasmagel of the padmagel in that region, resulting in increase in its elastic strength. Solation at the cathodal end and increase in elastic strength at the anodal end would result in the flow of plasmasol toward the cathode.

So, (not stressed BTW) there is the possibility that it’s not about memory at all but the strength and duration of the current.

[Zinjanthropos]

I did but I likened the positive charge to an obstacle, not a threat nor did it change the food. Even at the water hole, eventually you just gotta go and get a drink. Did they starve the amoeba?

You did say even just surround it with something unpalatable and they did showed a repulsion for that charge.

The anode is where chemicals lose electrons and the cathode is where they gain them. 

When you read about the reactions of amoeba to electricity, it does makes you wonder about the strength of the current, though. Some previous studies show that in a strong current, the entire plasmasol stops flowing and then reverses in direction, resulting in complete reversal in direction of movement of the organism.

They assume that the accumulation of positive ions increases the porosity of the plasmagel, since water passes or is forced through it and collects under the plasmalemma, forming a clear blister; that either the continued action of cations or this passage of water so the weakens the plasmagel that it finally breaks down completely, forming a pseudopod which extends toward the cathode; and that the accumulation of negative ions within the plasmagel on the side toward the anode decreases porosity of the plasmagel of the padmagel in that region, resulting in increase in its elastic strength. Solation at the cathodal end and increase in elastic strength at the anodal end would result in the flow of plasmasol toward the cathode.

So, (not stressed BTW) there is the possibility that it’s not about memory at all but the strength and duration of the current.

Have to be careful with those "so's" from now on.

I don't like bad weather but real bad would make me think twice about not going to the grocery store . It could even be life threatening. This experiment contained 'inclement weather' for the amoeba but not bad enough to stop it from going to the larder. 

I think the jury still out on this experiment.

[C C]

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.

---

I did but I likened the positive charge to an obstacle, not a threat nor did it change the food. Even at the water hole, eventually you just gotta go and get a drink. Did they starve the amoeba?

You did say even just surround it with something unpalatable and they did showed a repulsion for that charge.

The anode is where chemicals lose electrons and the cathode is where they gain them. 

When you read about the reactions of amoeba to electricity, it does makes you wonder about the strength of the current, though. Some previous studies show that in a strong current, the entire plasmasol stops flowing and then reverses in direction, resulting in complete reversal in direction of movement of the organism.

They assume that the accumulation of positive ions increases the porosity of the plasmagel, since water passes or is forced through it and collects under the plasmalemma, forming a clear blister; that either the continued action of cations or this passage of water so the weakens the plasmagel that it finally breaks down completely, forming a pseudopod which extends toward the cathode; and that the accumulation of negative ions within the plasmagel on the side toward the anode decreases porosity of the plasmagel of the padmagel in that region, resulting in increase in its elastic strength. Solation at the cathodal end and increase in elastic strength at the anodal end would result in the flow of plasmasol toward the cathode.

So, (not stressed BTW) there is the possibility that it’s not about memory at all but the strength and duration of the current.

Have to be careful with those "so's" from now on.

I don't like bad weather but real bad would make me think twice about not going to the grocery store . It could even be life threatening. This experiment contained 'inclement weather' for the amoeba but not bad enough to stop it from going to the larder. 

I think the jury still out on this experiment.

Minus the emergent features of a nervous system, what passes for "memory" in single cells will expectedly and bluntly look like the electrochemical equivalent of simple machine activities as well contributions from randomness factoring in. At that level it should probably be referred to as "retention"-like properties rather than memory. But once electronic systems got labeled with "memory" decades ago, the concept lost its distinctiveness -- is ubiquitously open to being applied to numerous non-living things (such as even symbols recorded on paper). As well as when you get down to the microscopic structure of a cell looking more like substances "non-biologically" interacting with each other rather than living entities interacting or cooperating to form communicative tissue, and organs.

[confused2]

I think it would be easy to underestimate the ability of single cells. Speaking as someone made up of single cells I see that (after an injury) when possible they put the (say) fingerprints back as they were before and if not possible they do a rough lining up with some sort of ridge when they can't make a good join - they can improvise while repairing. Lost a leg? You'll probably heal with the best possible 'no leg' result.
Amoeba have been doing what we have been doing (surviving) for as long as we (or any part of us) has. No reason to suppose they aren't at least an equal match for any cell that makes us up.