Signs of “consciousness” in fish and invertebrates?

The New York Declaration on Animal Consciousness, released on Friday, is signed by thirty-nine signatories from universities ranging from Canada to Australia, who say there is “at least a realistic possibility” that all vertebrates and many invertebrates have consciousness.

The statement is based on recent studies showing that snakes can recognize their own scent, crows can report what they see, octopuses can avoid pain, and vinegar flies can sleep — and that they sleep better when in the company of other vinegar flies.

For example, Christine Andrews, a professor of philosophy at York University, explains that scientific data supports the hypothesis that when a fish is hooked it “feels something,” but it is not yet clear whether or not that something is pain or distress.

She says the evidence shows it is reasonable to treat these creatures accordingly, by adopting fishing methods that quickly kill the fish or abandoning the practice of boiling lobsters alive.

Ms Andrews was one of the three main organizers of the ad. She says that a better understanding of consciousness in lobsters or crabs will help researchers understand consciousness in more complex animals like humans.

“We're not saying that these animals have internal monologues. What we're talking about here is a very simple cognitive level: the ability to feel something, the ability to have an experience,” said Noam Miller, a professor of biology and psychology who directs the University's Collective Perception Laboratory. Internal.” Laurier University.

There is no accepted definition of consciousness, and no specific test to identify it. Therefore, there is no real way to scientifically determine that something — even a person — has consciousness, Miller points out.

But there are many recognized “behavioral markers” of consciousness that can be tested rigorously and scientifically, such as decision making or pain avoidance, he says. Scientists have recently begun performing these tests on simple creatures, such as bees, crayfish, and lobsters, and have gotten some surprising results.

A 2022 study showed that bumblebees roll small wooden balls for no reason other than fun. Crayfish exhibit “anxious” behavior, which changes if they are given benzodiazepines, according to studies published between 2014 and 2017. In 2019, scientists discovered that cleaning fish seemed to recognize an unfamiliar mark on their bodies in front of a mirror and tried to take it away.

Miller said the statement released Friday brings together research showing that some creatures show behavioral signs of consciousness and concludes that because they have these signs, it is reasonable to assume they have consciousness. The statement challenges people – including other scientists – to stop assuming that these animals are unconscious or incapable of feeling anything.

“We're talking about modifying our initial hypothesis rather than making any definitive statement one way or another,” he said.