Instinct

Some animals know what to do right away.

Baby sea turtles move toward the ocean. They do not need to learn this. A small animal may climb into its mother's pouch.

A wet dog shakes water off its fur. Animals also build nests to stay safe. These actions happen without any training. They are part of how the animal is born. This helps them live and grow. Do you see animals doing things like this?

Instinct is a way of acting that is born into a living thing.

For example, baby sea turtles move toward the ocean right after they hatch. They do not need to learn this path. A wet dog also uses instinct to shake water off its fur.

Instinct is different from a reflex. A reflex is a very simple response. One example is when your eye closes in bright light.

Instincts are more complex sets of actions. They are often called fixed action patterns. This means the animal does the same steps every time.

Some scientists studied how these patterns work. Jean Henri Fabre looked at insects. He found that many animals repeat behaviors even in new places. He saw that wasps had a fixed pattern for catching prey. Other thinkers like Wilhelm Wundt studied how instincts help animals survive. He believed these patterns come from natural selection. This is the way nature helps species change over time. Even though instincts are inborn, animals can sometimes use experience to get better at them.

Instinct is a special way that living things act without being taught. It is an inborn way of behaving that most members of a species share.

For example, a newly hatched sea turtle will instinctively move toward the ocean. A marsupial will also climb into its mother's pouch right after being born. These actions happen because of biological factors rather than learning from experience. Instincts are different from reflexes, which are very simple responses. A reflex might be your eye closing in bright light or your leg jerking when a doctor taps your knee.

One way instinct works is through something called a fixed action pattern. This is a sequence of actions that happens the same way every time. These patterns are triggered by a specific event in the environment, known as a stimulus.

Once the pattern starts, the animal carries out the steps without variation. While the pattern itself is fixed, an animal might use experience to get better at it. For instance, a dog can improve its listening skills through practice. However, many animals cannot stop a fixed action pattern once it has begun.

Many scientists have spent their lives studying these natural behaviors. Jean Henri Fabre was one of the first to study the instincts of insects. He noticed that many animals repeat behaviors even when the situation changes. He studied wasps and found they had a fixed pattern for catching prey.

Another scientist, Wilhelm Wundt, founded the first psychology laboratory in 1879 at the University of Leipzig. Wundt believed that unconscious movements were built from sensations and emotions. He thought natural selection helped these instincts develop to help species survive.

Different thinkers have had many ideas about how instincts shape life. Sigmund Freud described instincts as biological forces that drive people to satisfy needs. He split these into life instincts and death instincts. In the 1930s, William McDougall argued that instinct was a better word for animal behavior. He suggested using the word propensity for humans instead. Later, in the 1950s, Abraham Maslow argued that humans do not have instincts. He believed humans have the power to override these strong drives.

Today, we use our knowledge of instinct to understand the world around us. Scientists like Konrad Lorenz showed how animals learn certain things through instinct. He famously saw a goose imprint on his boots and follow him. This showed that while the urge to follow is instinctive, the identity of the mother is learned. We can also see instinct in human babies. For example, six-month-old babies show a readiness to fear snakes or spiders. Understanding instinct helps us see how nature programs living things to survive.

Instinct is the inherent inclination of a living organism toward a particular complex behavior. These behaviors contain innate, or inborn, elements that exist without prior experience. Because they do not rely on learning, instincts are expressions of innate biological factors. Most members of a species share these behaviors to help them survive.

For example, sea turtle hatchlings instinctively move toward the ocean. Similarly, a newborn marsupial will instinctively climb into its mother's pouch. These actions are not taught; they are part of the animal's biological makeup.

A fundamental mechanism of instinct is the fixed action pattern (FAP). This is a sequence of actions that occurs without variation. A FAP is triggered by a clearly defined stimulus, which is an external event in the environment. Once the stimulus activates the pattern, the organism carries out the sequence.

While the pattern itself is invariant, an organism may use experience to change the details of its performance. For instance, a dog can improve its listening skills through practice. However, instincts must be distinguished from reflexes. A reflex is a simple response, like a pupil contracting in bright light.

Unlike complex instincts, reflexes are much more basic.

Many scientists have explored how these patterns function. Jean Henri Fabre (1823–1915) was among the first to study the instincts of insects. He observed that many animals repeat behaviors even in novel situations where the behavior no longer helps them. Fabre concluded that most animals cannot reason. He studied various wasp species and found they followed a fixed pattern when catching prey. He noted that while most individuals follow the species norm, some may show room for growth.

Fabre believed these were "fixed patterns" that did not change with the environment. He also rejected the idea that species evolve into one another.

Wilhelm Wundt (1832–1920) provided a different perspective through his work at the first psychology laboratory. Founded in 1879 at the University of Leipzig, his lab allowed him to observe human and animal behavior. Wundt viewed instinctive movements as the result of sensations and emotions. He believed these unconscious processes were the building blocks of consciousness. Wundt used natural selection to explain why instincts exist. He suggested that natural selection causes small changes in the nervous system over time. These changes create hereditary drives that lead to unconscious processes.

Other theorists defined instinct through the lens of motivation and psychology. Sigmund Freud described instincts as biological forces that motivate individuals to satisfy their needs. He categorized them into life instincts, known as Eros, and death instincts, known as Thanatos. In the early 20th century, William McDougall argued that many instincts are linked to specific emotions. By 1932, McDougall suggested that "instinct" was better suited for animals. For humans, he recommended the term "propensity" to describe goal-directed abilities that show strong plasticity. This reflected a growing scientific focus on the complexity of human behavior.

As research became more rigorous, the use of the term "instinct" for humans declined. In the 1950s, Abraham Maslow argued that humans no longer have instincts. He believed humans possess the ability to override strong drives. Konrad Lorenz and Nikolaas Tinbergen renewed interest in innate behaviors during this same era. Lorenz famously observed a goose imprinting on his boots. This showed that while the urge to follow is instinctive, the specific identity of the mother is learned. This distinction between innate urges and learned information was vital for modern biology.

Today, the concept of instinct remains a subject of study in various fields. In the 1960s and 1970s, textbooks still discussed human instincts, but the term eventually became outmoded. A survey of 12 best-selling psychology textbooks in the year 2000 found only one reference to instinct. However, some researchers still find instinctive bases for human actions. Amanda Spink notes that behaviors like cooperation and child rearing may be evolved psychological mechanisms. Even language acquisition is described by some, like Steven Pinker, as an instinctive process. Understanding these biological roots helps scientists map the connection between nature and behavior.