Regarding Pain in Crustaceans

Pax Christi, Everybody!

So it’s pretty much settled that fish can feel pain at this point, but what about crustaceans? If they can, to what degree can they suffer; is it a conscious thing?

Its worth remembering that pain is first an foremost a defense mechanism.

It our mechanism that something is damaging us or could damage and we should do something to stop it. It particularly useful for soft body creature like us since their can be quite a wide range of wound between one that is benign and one that is fatal. For hard bodied creatures like crustaceans its not the same, the difference between pain and death is much closer making pain not as useful.

But it’s not a indicator of consciousness. On top of the fact that pain is not mesurable, it make establishing anything more of a moral debate than a factual one. For me, morally not causing unnecessary suffering is always a good thing.

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A difficult question, especially the parts “to what degree” and “conscious thing”.

All(?) mobile animals react to tissue damage. How much this reaction is a sign of ‘suffering’ is not obvious. Suffering includes the idea of developed brain functions, reacting to tissue damage or apparent danger of tissue damage is not a sufficient sign of suffering.

In Finland, the legislation of animal testing includes vertebrates and cephalopods. For all other groups of animals, the prevailing view is that they do not suffer in the same sense as vertebrates. Cephalopods was a bit uncertain case, therefore they were included in the legislation and are treated as vertebrates.

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Well consider how ever trees respond to damage. A tree under herbivorous defoliation will begin to send signals throughout itself communicating to its leaves that they need to begin changing their chemical composition to make themselves more bitter, or by sending toxic substances ( think sap in milkweeds or tannins in oaks ) to make the thing consuming them get sick. Even the monarch’s that uses them as their host plants still can’t completely just eat the toxins. They instinctively begin chewing the leaves midrib vein at the base to reduce how much sap moves throughout the net veining in the leaf.

Even cooler is that the trees will send these same chemical signals to communicate to other trees by sharing information with one another through the fungal and root networking system ( mycorrhizal network ) to other trees, even trees in other species. They even nurse sick trees.

So I imagine almost all life has a way to signal damage regardless of how sentient we believe they are , or are not, and ect…


The intent of causing suffering to the innocent is evil. So is neglect, thoughtlessness. Dropping a live crab into a pot of boiling water is almost certainly OK; they’re dead before they can feel the process of dying.

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A wonderful idealism. But is it practical?

And can you identify an innocent?

At what point does killing for food become suffering? (Admittedly the whole reason for this thread is boiling something alive)

And finally, (although not directly to you) would the inability to cognisise pain make it acceptable? (might include the use of anesthesia)


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At least one animal welfare organisation has demanded that crabs should be stunned before boiling. They are a minority, the majority think that dropping a crab to boiling water is an acceptable way to kill it. Problems may arise if the crab is put to water before it boils, or too many crabs are dropped to water simultaneously (drops the temperature of the water).

Stunning of crabs is done with electricity. I read that there are such equipments intended for large restaurant kitchens. In large restaurants, there is often a need to boil a large amount of crabs. Stunning is done to ensure that the crabs do not suffer even if the temperature of the water drops when a large amount of crabs are put to the boiling water.

I don’t know how many restaurants have such equipment. Probably a minority. As noted in earlier messages, the prevailing view is that crabs do not suffer in the same sense as vertebrates, although they react to tissue damage.


To be honest, I wasn’t thinking about animal rights stuff. I was just wondering if one could even determine pain from creatures so poker-faced.


Why would a non-evil, rational actor intend to cause suffering to the innocent? The non-innocent are the guilty, those that have caused suffering by abusing power by deliberate fault or neglect, they need to be held to account and restore what can be restored or otherwise be punished, suffer loss of freedom, but never torture or fear of death. So no non-human creature can be guilty. No crab. Killing for food isn’t done with the intent of causing suffering, even halal and kosher killing. No secular method of killing for food should cause distress to the food animal, not even the sight and smell of death, even though they have no subjective fear of dying or death: they should be dead before they register any suffering. A captive bolt or electrocution should cause no suffering at all.

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Because it never crossed their mind.

Because the animal has no sense or feeling.

Because it is just a part of the process.

They need the flesh to be fresh.

There are probably thousands of rationales.

Their legitimacy is another matter entirely

. Richard

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There are 4 levels of life and consciousness

  1. genetic
  2. chemical
  3. neurological
  4. linguistic or mental

All living things from viruses to human beings have some awareness of both the environment and themselves, i.e. they respond to environmental condition and according to an identity of self apart from the environment respond to their own condition. But different organisms transmit and encode the information on environment and self at different levels of sophistication.

  1. The genetic is the simplest and most minimal level of life and consciousness. Viruses are an example of life that is purely genetic. Their information and repsonses are almost all genetic and only the species as a whole can really be said to be alive at all. That is where all the learning and adaptation is happening.
  2. The chemical however is probably where life began – with chemical cycles interacting in a way that can be called communication. All cells both prokaryotic and eukaryotic send chemical signals from one part of the cell to another in order to activate responses to both changes in the environment and changes in its own structure such as damage that needs to be repaired.
  3. Larger organism use a neurological system to send electro-chemical signals from one part of the organism to another. Neurological reports of damage is what most people mean by the word “pain.” But since the function is the same I see little reason why the chemical signals of damage in a cell should be considered all that different.
  4. Human beings have language as well as a neurological system, and a mental organization and life based on linguistic symbolization of information. While I certainly think this has a capacity for subtlety and abstraction which surpasses even that of DNA, as well as a speed of learning and adaptation that far surpasses the speed of genetic evolution, I don’t see why only this should be called consciousness. Greater consciousness to be sure, but I still think these other levels of awareness should be called consciousness also. In fact it can probably compared to the change in consciousness from a human infant to an adult. The change from the neurological consciousness of the infant to the linguistic consciousness of the adult is so great and profound that we pretty much cannot even remember the time when we were an infant. It was consciousness, but exceedingly dim compared to what we have later in life.
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They are all non sequiturs.


Depending on your definition of sequitur… I think you are wrong

All these reasons have a validity. They may not be ones you agree with or accept, but they could be argued with varying degrees of selfishness, callousness, or sheer ignorance.


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I imagine that tissue damage must be perceived as unpleasant to the crabs, even if they don’t experience it as badly as we do. Why not treat them humanely? There was a time when scientists decided that animals didn’t feel pain and did terrible things to them without anesthesia. This horrified Darwin, who believed that animals could experience pain and had emotions much like our own.

btw, some doctors claimed that Black people didn’t experience pain as whites do.

The question about crabs and pain might become irrelevant as the oceans fill up with plastic and warm from climate change.

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All of which are evil. My definition is the definition.

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The consequence may be evil but ignorance is part of innocence which is one of the few divine get-out clauses. Ignorance is morally neutral. it may not be a defence in law but we are not talking of human legalities here.


Removed various one line and bickering posts. Please stop.


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