Instincts: Definition, Theory, & Examples

Instincts are something we experience every day. We can find examples of instincts playing out in our own behaviors and in the behaviors of other animals. For example, we may observe our own instinct to find food when we are hungry. Animals and humans express an amazing array of instinctive behaviors that are often very complex. For example, the songs birds sing can be surprisingly complex, yet some birds are born knowing the tune. Some species of birds will even sing their song even if they aren’t raised around other birds of that species (Kroodsma & Konishi, 1991).
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• A baby’s reflexes: Babies are born with the ability to engage with parts of the world around them and respond appropriately to stimuli. For example, when the corner of a newborn’s mouth is touched they instinctively tilt their head back so that they are better able to find their mother’s nipple (Bennett et al., 2020).
• Migration of animals: Many species of animals, such as birds, butterflies, whales, and sea turtles, have an innate ability to migrate to particular locations at specific times of the year. For example, Caribou can migrate over 2,000 miles every year as the seasons change to find regions appropriate for birthing calves, finding food, and escaping mosquitoes.
• Hunger instinct: When we’re hungry, we’re motivated to seek food. The adaptive advantage of an instinct like this is probably pretty obvious.
• Pleasure instinct: We are motivated to seek out things that feel good and reject things that feel bad.
• Social bonding: Many animals, including primates, have an innate ability to form social bonds with other members of their species. This helps them to survive and reproduce by working together to protect themselves and their offspring.
• Grooming: Many animals, including primates, have an innate behavior of grooming themselves and other members of their group, which is important for maintaining hygiene and social bonds.
• Self-preservation: Instincts that lead animals to protect themselves from danger, such as avoiding poisonous or dangerous food, or escaping from predators.

Intuition and instinct are related concepts, but they have some important differences.

As described earlier, instincts refer to innate behaviors that help you to respond adaptively to stimuli. They are essentially pre-programmed and automatic and do not require conscious involvement.

Both instincts and intuition operate below the level of consciousness. In other words, if you were asked to explain an instinctive behavior or an intuition, you would have a hard time.
However, instinct refers to behavior, whereas intuition refers to a feeling. That is, intuition is the ability to know or understand something without the need to think about it at all. For example, imagine you are about to enter a spooky house in the dark by yourself. If you got a feeling in your stomach saying “please don’t, we’ve seen how this goes in movies”, that’s intuition. On the other hand, if you are walking through a park and suddenly raise your arm to cover your head as a frisbee comes zooming past your face, that would be an instinct.

These two concepts also differ in their innateness. Put differently, instincts are a part of your behavioral repertoire immediately and without any learning, whereas intuitions are something that evolves over time. With time and experience, you can develop your intuition and use it to help guide your decisions or find solutions to problems.

If you’ve ever reflexively stretched your right arm across your front seat passenger when making an abrupt stop or quickly scooped up a baby as it crawled toward a fire, you’re familiar with gut instincts. Though we might think we are speaking in metaphor when we talk about having a gut reaction, current research suggests that this might be a more literal event than we imagine.

Our stomachs actually have their own nervous system comprised of over 500 million neurons (Furness, 2012). This is the largest collection of neurons outside the brain, which is why it is sometimes referred to as the little brain or the second brain. The nervous system in our guts is connected to our brains. This union is unsurprisingly called the gut-brain axis. The gut-brain axis is known to play an important role in our emotions and some of our behaviors.

Recently, scientists have discovered that the gut-brain axis is controlled in large part by tiny bugs that live in our stomachs (Dinan & Cryan, 2017). Studies have shown that these little gut bugs, collectively known as the microbiome, are involved in stress responses (Konturek et al., 2011), symptoms of depression (Dash et al., 2015), and social behaviors (Desbonnet et al., 2014).
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There is also evidence to suggest that the microbiome can influence the brain mechanisms underlying emotional memory and decision-making (Bagga et al., 2018). This function of the microbiome may be responsible for the gut instinct we have when we are deciding whether or not we want to enter that spooky house by ourselves or if we should say yes to a marriage proposal. Though we don’t yet know exactly what gut instincts are, we can say that our guts are likely smarter than we think.

• “Telling us to obey instinct is like telling us to obey ‘people.’ People say different things: so do instincts. Our instincts are at war. If it is held that the instinct for preserving the species should always be obeyed at the expense of other instincts, whence do we derive this rule of precedence? To listen to that instinct speaking in its own case and deciding in its own favour would be rather simple minded. Each instinct, if you listen to it, will claim to be gratified at the expense of all the rest. By the very act of listening to one rather than to others we have already prejudged the case. If we did not bring to the examination of our instincts a knowledge of their comparative dignity we could never learn it from them. And that knowledge cannot itself be instinctive: the judge cannot be one of the parties judged: or, if he is, the decision is worthless and there is no ground for placing preservation of the species above self-preservation or sexual appetite.” ― C.S. Lewis
  
• “There can be as much value in the blink of an eye as in months of rational analysis.” ― Malcolm Gladwell
  
• “However, instinct is not conscious deliberation, nor mere consequences of the bodily organization, nor the result of a mechanism that lies in the brain, nor the effect of a mechanism that comes to the spirit from outside and is foreign to its essence, but rather the most distinctive accomplishment that springs from an individual’s or a group’s character.” ― Nietzsche
  
• “I have been and still am a seeker, but I have ceased to question stars and books; I have begun to listen to the teaching my blood whispers to me.” ― Hermann Hesse
  
• “Instinct is a marvelous thing. It can neither be explained nor ignored.” ― Agatha Christie
  
• “Trust instinct to the end, even though you can give no reason.” ― Ralph Waldo Emerson
  
• “In art as in love, instinct is enough. ” ― Anatole France
  
• “Oh darling, don’t be bitter. It’s the first instinct of the weak.” ― Sarah Dessen
  
• “You can have tons of talent, but it won’t necessarily keep you fed. If you have sharp instincts, through, you’ll never go hungry.” ― Haruki Murakami
  
• “It is impossible to overlook the extent to which civilization is built up upon a renunciation of instinct….” ― Sigmund Freud
  
• “The first reaction is surely the most natural one, but not always the most correct one; thereupon, the invention of apologies.” ― Criss Jami
  
• “Being able to act intelligently and instinctively in the moment is possible only after a long and rigorous of education and experience” ― Malcolm Gladwell
  
• “There is a part of us that knows the timing of any relationship. It knows things that we cannot work out. It knows when to say yes. It knows when to say no. It knows when to wait. It knows when something has finished. It knows when something has started. It knows when we have a responsibility to another person. It knows when the ties are untied. It will not betray us or another.” ― Donna Goddard

• Arguello, J. R., & Benton, R. (2017). Open questions: Tackling Darwin’s “instincts”: the genetic basis of behavioral evolution. BMC biology, 15(1), 1-3.
• Bennett, R., Lashley, L. K., & Golden, C. J. (2020). Newborn Reflexes.
• Dash, S., Clarke, G., Berk, M., & Jacka, F. N. (2015). The gut microbiome and diet in psychiatry: focus on depression. Current opinion in psychiatry, 28(1), 1-6.
• Desbonnet, L., Clarke, G., Shanahan, F., Dinan, T. G., & Cryan, J. (2014). Microbiota is essential for social development in the mouse. Molecular psychiatry, 19(2), 146-148.
• Dinan, T. G., & Cryan, J. F. (2017). Gut instincts: microbiota as a key regulator of brain development, ageing and neurodegeneration. The Journal of physiology, 595(2), 489-503.
• Furness, J. B. (2012). The enteric nervous system and neurogastroenterology. Nature reviews Gastroenterology & hepatology, 9(5), 286-294.
• Konturek, P. C., Brzozowski, T., & Konturek, S. J. (2011). Stress and the gut: pathophysiology, clinical consequences, diagnostic approach and treatment options. J Physiol Pharmacol, 62(6), 591-9.
• Scheiber, I. B., Weiß, B. M., Kotrschal, K., & Hemetsberger, J. (Eds.). (2013). The social life of greylag geese. Cambridge University Press.
• Wallenstein, G. (2009). The pleasure instinct: Why we crave adventure, chocolate, pheromones, and music. John Wiley & Sons Incorporated.​