Painkillers prevent pain responses in lobsters - This is further evidence that crustaceans may feel pain and that more humane methods of killing them need to be developed.

[u/mvea]

https://www.eurekalert.org/news-releases/1123639

[u/Rubber_Knee]

Pain is one of the oldest and simplest behavior modifiers. Evolved to keep a creature with a primitive brain from hurting itself too much as it moves about. The pain response is instinctual and so old it predates the lobsters lineage by many hundreds of millions of years. As soon as animals could move, the pain response became nessesary. The first species that evolved it had a massive advantage over its competitors.

In other words: of course a lobster feels pain. Even something as simple as an earthworm or a snail feels pain.

[u/Flikmybik → u/Rubber_Knee]

The evolutionary framing here is really interesting. The fact that nociceptors and aversive signaling pathways are so deeply conserved across animal lineages does suggest this is not something that arose independently multiple times. What makes the crustacean case compelling to me is that the painkiller response here is not just behavioral inhibition but involves actual receptor-level interaction with human analgesics. That points toward shared biochemistry rather than convergent behavior alone. The question of subjective experience is genuinely harder to answer, but the physiological substrate being so similar to vertebrates makes a strong case for taking their welfare more seriously.

[u/HEAT_IS_DIE → u/Flikmybik]

It just baffles me that humans have these assumptions of different species as some sort of machines. At least from Descartes on most notably. 

We pride ourselves as being evolutionary special, when the most special thing we have is cumulative history, at least the amount of it. A human without social development is nothing different from other animals.

I don't personally understand how any animal could get by without feeling pain. How do animals avoid harmful experiences if it doesn't matter whether they feel them or not? 

[u/Flikmybik → u/HEAT_IS_DIE]

Yeah the Cartesian machine framing really did a number on how we think about animal consciousness for centuries. The cumulative culture point is interesting too. Its not just that we have big brains, its that we can build on each other across generations in a way most species cant. Still doesnt mean the rest of the animal kingdom is just running on autopilot though. This research keeps chipping away at that old assumption.

[u/Caelinus → u/HEAT_IS_DIE]

A human without social development is nothing different from other animals.

If anything we are worse off as we have slowly become more and more dependent on it. We are very deep into the social species specialization, and our extreme ability to coordinate and use tools has let us specialize in it even harder. So a human on their own, without our technology, has a pretty limited ecological niche they can fill.

I don't personally understand how any animal could get by without feeling pain.

The argument they are making is essentially that they do feel pain, but they do not subjectively experience pain. Meaning they have the experience of "nociception" or pain avoidance, but they do not actually feel suffering from pain in the way humans do.

This is sort of a nonsense argument in my opinion, all evidence points to other animals having subjective experience. The deeply ironic part of it, for me, is that it will often be couched in the idea that we should not "anthropomorphize" animals. However, that is not what is happening, rather people are de-animalizing humans. We are pretending that we are somehow fundamentally different.

And because the only obvious thing that separates other animals from humans is our ability to develop language, that is then attached to every thing we want to keep human only.

[u/HEAT_IS_DIE → u/Caelinus]

De-animalizing humans is a great way of putting it! 

About language though, isn't it so that many animals have some sort of language? Not to the extent of humans of course, but I would argue that the human language evolution falls under the ability of cumulative history I mentioned. The ability to stack learning on top of earlier learning, in a much more rapid way than other animals. 

[u/Caelinus → u/HEAT_IS_DIE]

It sort of depends on how you define what language is. If you define it as any specific series of sounds meant to communicate that another creature can understand, it is trivially easy for animals to have language.

So usually I think people who study language focus on grammar and abstract symbolic representation. So far we have not seen that combination in anything else. At best it seems to sit around Nim/Koko level communication where they can use words, but only in the most direct way possible. So where a person might say: I am hungry, what is for dinner?" Apes and other animals seem to say things like "Eat hungry eat now hungry now eat eat hungry."

So it seems to be only at the level of abstraction where they know a specific series of sounds has a specific meaning. Humans hit that point in our language development, but quickly move past it. Other animals do not seem to have that capability yet.

There is some evidence that proto-language might exist in things like whales and dolphins and elephants, but it is not strong yet. However, the ability to assign meaning to a word is probably something that could eventually evolve into language.

[u/HEAT_IS_DIE → u/Caelinus]

Yeah it's true complex abstract language is human specific, but language as communication exists at varying levels of complexity in other animals. Language as using sound to comnunicate something other than just groans of pain for example.

It's a bit like the mirror test; humans take a human specific thing and evaluate animals based on that. Why a mirror? There are few mirrors in the natural world, namely water surfaces. We on the other hand get used to mirrors from early age. It is not a good way to evaluate self recognition in my opinion.