Study: Fish Have Emotional States

According to a study published in Scientific Reports, researchers have found that fish have emotional states caused by how they perceive external stimuli. The study reinforces similar findings regarding the emotional lives of other animals.

While evaluating emotional states in nonhuman animals is difficult because their emotions can’t be verbalized, scientists can detect and study emotional states through the behavioral and physiological changes associated with them. In this study, the team of scientists, led by Rui Oliveira, placed the fish in a series of different environments and measured their brain activity and levels of the stress hormone cortisol. The scientists observed that individual fish responded differently to the same stimulus depending on how they assessed that stimulus.

Oliveira said:
This is the first time that physiologic and neuromolecular responses have been observed in the central nervous system of fish in response to emotional stimuli based on the significance that the stimulus has for the fish. The occurrence of the cognitive assessment of an emotional stimulus in fish means that this cognitive capacity may have “computational” requirements simpler than what has been considered until now, and may have evolved around 375 million years ago.
This isn’t the first study, however, to show that fish are sentient beings with emotional lives. A recent article in The New York Times reveals that fish who linger at the bottom of the tank may be suffering from depression.

Last year, a study by Royal Society Open Science revealed that farmed salmon suffer from severe depression. According to the study, many salmon at fish factory farms appear to give up and float lifelessly in their enclosures. These depressed fish are known as “drop outs.

Like land animals, fish are intelligent and sensitive beings. An article by Vox detailed a multitude of fish abilities, including their abilities to “learn from each other, recognize other fish they’ve spent time with previously, know their place within fish social hierarchies, and remember complex spatial maps of their surroundings.” Similarly, a study published in Nature Scientific Reports found that fish look out for each other when searching for food.

Scientists have found time and again that fish experience pain. They even compare fish to dogs, cats, and other animals in the way they feel pleasure.

Sadly, the seafood industry treats fish as mere objects. A 2011 Mercy For Animals undercover investigation at a fish slaughter facility exposed fish being skinned alive. As the fish gasped for oxygen, their skin was ripped off with pliers. They thrashed and fought to escape the workers’ knives.

See for yourself.

We can take a stand against the blatant abuse of these amazing beings and other animals by leaving meat, dairy, and eggs off our plates. Click here to learn more about switching to a compassionate vegan diet. And check out these cruelty-free, sea-inspired recipes.