They are extraordinary creatures – with their intelligence distributed throughout their eight-armed bodies, rather than centralised in a single brain like in humans, they rapidly learn new skills, are highly adaptive, display complex behaviour, are able to solve complicated puzzles, have preferences for different individuals and can even be playful.
Whether they have what we recognise as emotions remains hotly debated. But the issue could up-end humans’ moral decision-making, according to new research by a York University expert in animal minds.
Professor Kristin Andrews, a philosopher and the York Research chair in animal minds, has been working alongside a team at the London School of Economics on a report commissioned by the UK government, which she said "found there is strong enough evidence to conclude that decapod crustaceans and cephalopod molluscs are sentient".
As a result of some of this work, the UK government is considering amendments to animal welfare legislation which would recognise the sentience of these creatures and their ability to feel pain.
In November last year, the scope of the Animal Welfare (Sentience) Bill was extended to recognise lobsters, octopuses and crabs and all other decapod crustaceans and cephalopod molluscs as sentient beings, in recognition of the research carried out by the LSE-led team.
This week the bill reached its final stage – the consideration of such amendments – before it reaches royal assent and becomes law.
The government has said the legislation will be for future guidance on animal welfare only and will not impact industries such as fishing or restaurants.
Ahead of the new recognition of these creatures’ abilities, Prof Andrews has written an article in the journal Science about the new legislation and what the implications are for thought around animal sentience, emotions and how humans interact with them.
She said it has long been thought in western culture that other animals don’t feel pain or have emotions.
“It’s been a real struggle even to get fish and mammals recognised under welfare law as sentient. So, it’s pretty cutting-edge what seems to be happening in the UK with invertebrates,” she said.
The research discusses how pre-verbal human babies were considered not to feel pain up until at least the 1980s.
And it highlights how it is still thought by many that animals, including invertebrates, don’t feel pain and only have unconscious reactions to negative stimuli.
However, research on mammals, fish, octopuses, and to a lesser extent crabs, has shown they avoid pain and dangerous locations, and there are signs of empathy in some animals, such as cows – they become distressed when they see their calf is in pain.
Prof Andrews says a new recognition of the sentience of invertebrates opens a moral and ethical dilemma: humans can say what they feel, but animals and humans aren’t able to interact in the same way.
“However, the research so far strongly suggests their existence,” said Prof Andrews, who is also working on a research project called Animals and Moral Practice.
“When we’re going about our normal lives, we try not to do harm to other beings. So, it’s really about retraining the way we see the world," she said.
"How exactly to treat other animals remains an open research question. We don’t have sufficient science right now to know exactly what the proper treatment of certain species should be. To determine that, we need greater cooperation between scientists and ethicists.”
She suggested there may be a point when humans can no longer assume that crayfish, shrimp, and other invertebrates don’t feel pain and other emotions.
“If they can no longer be considered immune to felt pain, invertebrate experiences will need to become part of our species’ moral landscape,” she said.
“But pain is just one morally relevant emotion. Invertebrates such as octopuses may experience other emotions such as curiosity in exploration, affection for individuals, or excitement in anticipation of a future reward. It may be time to look at our world differently."
The article is published in the journal Science.
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