Some scientists have argued that killer whales should be considered non-human persons because of their capacity for emotions and intelligence. The killer whale’s brain weighs an impressive 15 pounds. Out of all ocean animals, their brain is the second largest.
This powerful mind may be why killer whales are able to teach hunting techniques and learn local dialects. In some pods, killer whales pass on behavior patterns that last for generations. This is longer than any species other than humans. Passing on behavior patterns and hunting techniques happens because the whales communicate in a language and can actually teach skills to each other.
Because of these abilities, some researchers believe that killer whales should be considered non-human persons. Their brains have cortical folding similar to humans, which means they are most likely capable of huge amounts of cortical processing. In addition, the insular cortex and the limbic lobe are both larger in killer whales than they are in humans. While the insular cortex is linked to hearing, the limbic lobe is connected to emotions. In humans, this area is in charge of memories, emotions and emotional behaviors.
Spindle cells are unique because they help the limbic system process empathy and create a social organization. Scientists previously thought only great apes had these cells, but it turns out that several whale species contain them as well. Killer whales actually have a higher relative number of spindle cells than humans do.
Because of their emotional capabilities, social drive and ability to empathize, it is unsurprising that a killer whale may become lonely or vicious in captivity. Killer whales use verbal and non-cortical cues to interact socially and coordinate group behavior. These whales have exhibited feelings such as anger, joy, fear and self-awareness. While there is no evidence these whales have ever killed anyone in the wild, they have killed their captors when forced to live alone in a tank. Like humans, they require their social group in order to be happy and content.