Sentience

social sharks
Research has begun to challenge the long-standing perception of sharks as solitary hunters, revealing instead a complex social structure that requires a high level of cognitive function.

Sharks as social and sentient beings

Recent scientific research has begun to challenge the long-standing perception of sharks as solitary hunters. Rather, it reveals their complex social structure that is borne out of a high level of cognitive function.

In fact, these studies suggest that sharks possess a level of social intelligence, problem-solving skills and even emotional intelligence that far surpass previous beliefs, offering a fresh perspective on their behaviour and potential sentience.

Giant Pacific Octopus - photo by Andrey Bizyukin
Giant Pacific Octopus interact with divers

Do octopuses have an emotional life?

Octopuses have intrigued scientists for years, because they have both long- and short-term memory, they remember solutions to problems, and they can go on to solve the same or similar problems. They have been known to climb aboard fishing boats and open holds in search of crabs. They can figure out mazes, open jars, and break out of their aquariums in search of food.

Their apparent problem-solving ability has led cephalopods to be recognised as intelligent.

Do octopuses dream?

Scientists used to think that only mammals and birds experienced different sleep states. More recent research, however, has revealed some reptiles and cuttlefish -- another cephalopod and relative of the octopus -- show non-REM and REM-like sleep.

A new study has found that the octopus has ‘quiet’ and ‘active sleep’, with different episode duration and periodicity, and experiences active sleep after a long episode of quiet sleep.

Sand Tiger Shark. Evidence of complex social behaviors in sharks and other elasmobranchs is sparse, however we are beginning to understand the importance of studying shark aggregations

Sand tiger sharks have a friendly side

While many sharks are solitary predators, some are known to live in groups and are suspected of engaging in complex social behaviors. Meanwhile others simply aggregate due to similar habitat, food, or mating requirements.

Using a novel tagging procedure, scientists in the United States, have discovered that some shark species like to spend their time mixing and chilling out together.

Observations made in 2006 and 2007 suggests that dolphins and whales may experience complex emotions once believed to be reserved for human beings such as deep grief at the death of a loved one

Do whales and dolphins grieve their dead?

A study by researchers from University of Milano-Bicocca describes observations of adults carrying dead calves and juveniles in 7 toothed cetaceans (odontocetes). The observation was based on 14 events from 3 oceans. The seven species studied were Indo-Pacific bottlenose dolphins, killer whales, Australian humpback dolphins, sperm whales, Risso’s dolphins, short-finned pilot whales, and spinner dolphins.

Some sharks are smart cookies

Researching the intelligence of the grey bamboo shark a team of researchers at Rheinische Friedrich-Wilhelms-University in Bonn, Germany showed that sharks could be trained to recognise and remember shapes for an extended period of time.

First juvenile sharks were subjected to three different cognition experiments, one at a time, and then tested to see how long the sharks could remember their training.

Cognition in Sharks

A difficulty in obtaining information about wild animal behaviour is that detailed observations of different individuals is necessary over long periods of time, and this is especially hard to achieve with sharks. But in the shallow lagoons of French Polynesia, such observation was possible without the encumbrance of scuba gear, and without the problem of the shark disappearing into the depths.