Are Sharks Sentient Beings?

Sharks have swum the oceans for over 400 million years, but only recently have scientists begun to explore their cognitive and emotional capacities in earnest. Can these apex predators feel, think, and experience emotions – are they sentient?

If you’re short on time, here’s a quick answer: While more research is still needed, mounting evidence suggests sharks do possess a level of sentience including signs of curiosity, problem-solving skills, social bonding, and experiencing distress.

Defining Sentience and Shark Cognition Research

What is meant by sentience

Sentience refers to the ability to perceive and feel things subjectively. A sentient being is aware of its own existence and experiences sensations like pain, hunger, joy and fear. Sentience implies some degree of consciousness and cognition.

There is debate around which species are truly sentient, but most scientists agree that all vertebrates, including sharks, meet the criteria for sentience.

Documented cognitive abilities in sharks

Research has revealed some impressive cognitive abilities in sharks that point to sentience:

• Sharks have excellent long-term memories and can remember the location of prey for months or even years.
• Some species like Port Jackson sharks exhibit complex social behaviors and may even play with each other.
• Sharks can problem solve and have passed the mirror test, recognizing their own reflection.
• Their brains contain neuron densities and structures analogous to the pallium in mammals, associated with consciousness.

Studies of shark brains have found over a dozen different areas that perform higher functions like integration of sensory information and control of behavior, supporting the idea that sharks have subjective experiences.

The emotional lives of sharks

There is evidence that sharks feel emotions much like humans and other advanced vertebrates:

• Stress hormones have been measured in sharks put under threat, similar to humans experiencing anxiety.
• Sharks appear to exhibit curiosity when exposed to novel objects, cautiously investigating them.
• Injured sharks grimace, suggesting they feel physical pain.
• When given opioids, sharks’ reaction times slow down like those of mammals experiencing pain relief.

While more research is still needed, these signs point to sharks having rich emotional inner lives that compel ethical consideration of their welfare.

Evidence That Sharks Are Sentient Beings

Observational accounts of shark behavior indicating sentience

There are numerous anecdotal reports of sharks displaying complex behaviors that suggest advanced cognitive abilities and sentience. For example, research shows some sharks cooperating with fish called remora that attach to them to eat parasites – suggesting an ability to understand symbiosis and mutual benefit.

There are also accounts of injured sharks returning to specific areas where humans had previously helped them, suggesting memory, recognition and gratitude.

Brain structure and neurochemistry comparisons to mammals

Recent neuroscience research found that in some ways, the shark brain more closely resembles the mammalian brain than that of bony fish. For example, shark brains contain more Von Economo neurons, associated with cognition in apes and whales.

They also have an abundance of neuroprotective proteins found in complex mammalian brains.

This emerging evidence of mammalian-like neurochemistry suggests that sharks may have greater sentience than traditionally believed.

Arguments that sharks meet the criteria for sentience

There is a compelling case that sharks meet many scientific criteria used to establish sentience in animals. For example, sharks demonstrate problem solving skills, have social behaviors and personalities that differ between individual sharks, and show signs of curiosity.

Their forebrain and cerebrum are very large and complex compared to most fish. Researchers argue that their ability to learn and remember in flexible ways clearly meets cognitive thresholds for sentience.

Skepticism and Limits of Shark Sentience Research

Alternative explanations for shark behaviors

While some researchers argue that certain shark behaviors suggest sentience, others propose more parsimonious explanations. Sharks may exhibit complex social behaviors, but these could be driven by instinct rather than subjective awareness.

Their ability to navigate complex environments may rely primarily on their excellent senses, rather than mental representations of their surroundings. Apparent personality traits could simply reflect variability in temperament, rather than self-aware individuality.

So while sharks show intriguing potential for sentience, their behaviors allow for interpretations besides conscious awareness. Carefully ruling out simpler reflexive or innate drivers of shark behavior poses a continuing challenge in this research area.

Issues with anthropomorphism in animal cognition research

A common critique of animal sentience research is that it falls prey to anthropomorphic biases, inappropriately attributing human-like qualities to animals. For instance, interpreting sharks’ social groupings as friendships may reflect our own social perspectives more than sharks’ subjective experiences.

Perhaps sharks cluster together simply because they are attracted to the same feeding or breeding resources, not due to any sense of companionship. While anthropomorphism can produce testable hypotheses about animal cognition, researchers must rigorously guard against implicit assumptions that other species share our own complex inner worlds.

Striving for an objective, critical perspective represents an ongoing struggle in the study of shark sentience and consciousness.

Difficulties studying the subjective experiences of sharks

Researchers face profound challenges in studying sharks’ subjective, inner experiences. Unlike humans, sharks cannot directly communicate what their mental states feel like or what emotions they experience. Scientists are limited to observing shark behavior and inferring internal processes.

Advanced neural imaging may eventually offer insights, but currently lacks the resolution to determine if sharks possess sentience or consciousness akin to humans. Our understanding of shark cognition thus relies heavily on analogy, intuition and anthropomorphism, rather than directly tapping into sharks’ subjective worlds.

All this underscores the difficulty of conclusively determining the presence and nature of sentience in these marine apex predators. The inner lives of sharks may long remain an enigma given the current limits of our investigative tools.

The Moral Implications If Sharks Are Sentient

Rethinking shark culling, finning and trophic cascade effects

If evidence continues to show that sharks have greater cognitive abilities and emotions than previously thought, we may need to rethink practices like shark culling and finning. Shark culling, the killing of sharks to reduce their population after a shark attack on a human, may be unethical if sharks have moral value as sentient beings.

Similarly, the practice of shark finning, where shark fins are harvested for food and traditional medicine, could be considered inhumane if sharks have the capacity to suffer.

We may also need to be more careful about trophic cascade effects when culling shark populations. As apex predators, sharks help maintain balance in ocean ecosystems. Large-scale shark culling can disrupt this balance in unintended ways, impacting coral reefs and other marine species.

If sharks are sentient, we have an additional moral duty to consider their interests when managing ocean ecosystems.

Changing human attitudes and conservation efforts

Evidence for shark sentience could transform human attitudes toward sharks. Instead of viewing them as mindless “killing machines”, people may begin to see sharks as fellow cognitive beings deserving of moral consideration. This shift could increase public support for shark conservation efforts.

However, attitudes are slow to change. Educational campaigns showing sharks’ impressive learning abilities and unique personalities may help. So could interactions with trained sharks at aquariums to highlight their sentience. Stronger legal protections for sharks may also be needed to drive action.

Conservation strategies will need to become more shark-centric. For example, preventing habitat loss and overfishing is crucial, as sharks are slow to mature and have few offspring. While sentience alone does not confer a right to life, it does require minimizing shark suffering from harmful human activities.

Further research priorities in elasmobranch cognition

More research is urgently needed to better understand shark and ray cognition and sentience. Some priorities include:

• Learning more about their pain perception and nociception pathways.
• Studying their emotional lives and capacities for suffering.
• Testing different shark species’ cognitive abilities through maze tests, match-to-sample tasks, etc.
• Examining their self-awareness and theory of mind.
• Investigating their social bonds and relationships.
• Exploring how human-caused stressors affect their behavior and welfare.

We also need a deeper understanding of the neuroanatomy, neurochemistry, and neurophysiology underlying shark cognition. Brain size alone does not determine mental complexity; neural networking also plays a key role.

Research focuses should include both wild and captive sharks. New tracking technologies will enable insights into cognition and behavior in the wild. Controlled studies with captive sharks also remain important.

With further research, we can gain a clearer picture of sharks as thinking, feeling beings. This will allow more ethical treatment of these fascinating creatures who have shared the oceans with us for millennia.

Conclusion

While more observational and experimental data is still needed, a growing body of evidence points towards sharks possessing a level of sentience. This may necessitate re-evaluating our relationship to and treatment of these apex ocean predators that have existed for hundreds of millions of years on our planet.