Just as vertebrates differ greatly in intelligence and sentience, invertebrates may differ greatly too. The seafood industry is taking heed:
Assessing the evidence is tricky. In recent years, we have discovered that some invertebrates — octopuses, squid, and cuttlefish, for example — are much more intelligent than we used to think. That’s also true to some extent of lobsters and crabs. But they are special cases. Many other invertebrates, like clams, show little sign of cognitive awareness.
As Mesa goes on to note, it is hard to tell without skilful research. Many invertebrates do not have “faces” and their brains are organized very differently from ours. And, bluntly, some invertebrate behavior does not point in the direction of much sentience. As she observes, “Locusts continue to chew leaves as they’re being consumed by predators, and many insects don’t limp in response to injury.” Then there’s the praying mantis:Denyse O’Leary, “Asked at The Scientist: Do invertebrates have feelings?” at Mind Matters News (May 31, 2022)
Eric Cassell, author of Animal Algorithms (2021) and entomologist Deborah M. Gordon describe the behavior of insects like ants as algorithmic, like that of a computer — which means that they probably aren’t “feeling” anything.Denyse O’Leary, “Asked at The Scientist: Do invertebrates have feelings?” at Mind Matters News (May 31, 2022)
Takehome: What we are learning is that invertebrate status is not, by itself, evidence of an inability to think or feel — as we used to suppose. In a world full of information and intelligence, it’s not nearly as tidy as our biology teachers thought.
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Researchers ask—serious question — do crabs have emotions?Recent research has created some unexpected ethical problems for the seafood industry. There are no simple answers to why some invertebrates show more intelligence and emotion than we would expect.
How could we know if an octopus or lobster felt pain? Researchers found that, when it comes to awareness, octopuses were the stars, followed by lobsters, crayfish, crabs, etc. How a life form acquires the ability to make intelligent decisions (and feel pain) is a fruitful mystery but it might blow up some assumptions about evolution.