FRANKLIN the cuttlefish considered the juicy prawn meat morsel in front of her. As mouth-watering as it looked, she resisted temptation and waited for her favourite meal to become available – live shrimp. Her self-control is impressive and comparable to what we see in chimpanzees and crows.
Self-control is a vital cognitive skill that underpins decision-making and future planning. In humans, these abilities are linked to sentience because they are thought to involve conscious experience. Imagining future choices is accompanied by an awareness of the projection of self in time – what will my future self want, and how different will it be from what I want now? Some animals possess similar cognitive abilities, but cannot report their experiences, and so whether they are sentient is an ongoing debate.
This topic has recently taken the spotlight in the UK with a new bill currently making its way through parliament that will recognise certain animals as sentient, including mammals, birds, fish, reptiles and amphibians. This will give them greater protections in law, particularly in the context of reducing pain and suffering.
This is a good step forward. However, as it stands, invertebrates like Franklin aren’t being included.
Invertebrates show plenty of behavioural signs of sentience. But because their neurological architecture greatly differs from that of vertebrates, it is often wrongly assumed that they don’t possess the appropriate hardware to experience emotions.
Despite the differences, there are many brain structures across both groups that perform similar functions. Invertebrates such as cephalopods (octopus, cuttlefish, squid) and decapods (crayfish, crabs, lobsters, prawns) possess brain receptors and structures that can process negative emotions, such as the vertical lobe in cephalopods – responsible for learning and memory. They also possess nerve cords that transfer information about the location of an injury from the peripheral nerves to the central brain.
Consequently, groups including Crustacean Compassion, the RSPCA and the Conservative Animal Welfare Group (CAWG) are urging for the inclusion of cephalopods and decapods in the UK’s Animal Sentience Bill. They also argue that the intelligence observed in cephalopods, particularly octopuses, should grant them protection.
It is important to remember animal protections aren’t just about intelligence, as sentience doesn’t necessarily require it – an animal doesn’t need to be able to plan for the future to be capable of suffering. For example, there is no evidence that crabs plan for the future, but, when injured, they attend to their wounds in a self-protective manner, such as hiding declawed arms behind healthy claws to protect their wound. They also appear to shudder when wounds are touched.
Cephalopods also behave in a way that is indicative of being able to experience emotions. For example, cuttlefish learn to avoid the claws of their crab prey after being pinched and instead attack them from behind. Octopuses with injured arms curl their adjacent arms around the wound and after being injured they avoid chambers where an injury was inflicted, preferring to seek refuge in chambers that provide access to a local anaesthetic for pain relief.
Countries such as Norway, Sweden and Austria have already afforded invertebrates legislative protection, and this has resulted in much improved animal welfare standards, such as in the storage and slaughter of decapods within the food industry.
Others now need to catch up. While there are neurological differences, invertebrates are likely to experience pain and show signs of sentience. Animal protection laws should reflect that.
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