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Biology 103
2002 First Paper
On Serendip

Instinctive Behavior

Amanda Maclay

Perhaps it can be said that the distinguishing factor between humans and animals is that animals act out of instinct and humans out of will. What are instinctive behaviors and do humans ever act out of instinct rather than their own will? This paper will determine innate activity and decide whether or not this may be an appropriate difference between animals and humans.

Ethnologists, those who study animal behavior, believe that every species have routine movements that appear to be automatic in a way that relates to their structural systems (1). Konrad Lorenz, one of the leading scholars in this field, names these patterns as "Fixed Action Patterns" (2). Further defining instinctive behavior, ethnologists found particular characteristics, which include inherent structured systems and the adaptive functions (1).

Inherent structured systems are highly correlated with innate activity; many behaviors of animals are sufficiently unvarying and provide as particular characteristics of bodily structures. For example, the web spinning movements of spiders are a direct usage of its bodily construction. Or, the burrowing habits of marine worms employ operations of structure (3). Such movements that are typical to instinctive behavior include, eating, care of body surface, escape from predators, social behavior, and sexual interaction. Most of these innate activities involve the particular usage of a physical structure that is specific to each species.

Not just simple responses to an external stimulus play a role in instinctive behavior; instinctive activity involves sequences of behavior that run a predictable course. These behaviors may last seconds, minutes, hours or even days. Exemplifying this, we can refer to a particular species of digger wasp, which finds and captures only honeybees. With no previous experience, a female wasp will unearth an intricate burrow, find a bee, paralyze it with a careful and precise sting to the neck, pilot back to her discreet home, and, when the larder has been supplied with the correct number of bees, lay an egg on one of them and seal the chamber. The female wasp's whole behavior is designed so that she can function in a single specialized way. Ethnologists believe that this entire behavioral sequence has been programmed into the wasp by its genes at birth (3) thus resulting the high correlated sequences between heredity and instinctive behavior.

Given that instinctive behavior supposes to be hereditarily based, and therefore shaped by the forces of natural selection, it follows that most of the outcomes of instinctive activity contribute to the preservation of an individual or to the continuity of the species; instinctive activity tends to be adaptive, which implies the alteration of a living organism to its surroundings. There are two different types of adaptation; one, which involves the accommodation of an individual organism to a sudden change in environment and the other, occurs during the course of evolution and hence is called evolutionary adaptation. (1) Looking at the development of monotremes and marsupials, we can observe evolutionary adaptation. When Australia became a separate continent some 60 million years ago, only monotremes and marsupials lived there, with no opposition from the placental mammals that were emerging on other continents. Although only two living monotremes are found in Australia today, the marsupials have filled most of the functions open to terrestrial mammals on that continent (3). Thus, these animals developed changes in their genetic structures over time, creating different innate behaviors.

Overall, one of the main distinctive features of instinctive activity is the ability to react to an external stimulus the correct way the first chance (and every time thereafter) the animal receives. This feature distinguishes this particular behavior from what ethnologists call learned behavior, which scientists have discovered are actions that take place from conditioning an animal to learn the right way. Will, which can be defined as the power of choosing one's own actions (4), may be related to learned behavior; in order to choose, one must have a sense of what the outcome will be, therefore causing the choice to be learned rather than instinctive.

The physiological adaptations that made humans more flexible than other animals allowed for the development of a wide range of abilities and an unparalleled adaptability in behavior. The brain's great size, complexity, and slow maturation, with neural connections added through at least the first twelve years of life, means that learned behavior largely modifies stereotyped, instinctive responses. So, those behaviors that form heredity and adaptation change, according to each individual, to develop into learned actions. Scientists believe that each new infant, with relatively few innate traits yet with a vast number of potential behaviors, must be taught to achieve its biological potential as a human (3). Therefore, many of the human actions are instinctively learned behaviors in that the brain which is genetically structured to obtain learned information.

While animals mostly act out of instinctive behavior and humans, due to their particularly designed brain, act out of learned behavior (or as I related to will) this is not a sufficient characteristic to distinguish between humans and all other animals. Ethnologists do believe that there are some features of humans that are instinctive, such as eyebrow raising when eyes widen in social interactions, but this field remains unsound. There seems to be many arguments, which claim that all behaviors within the animal kingdom are learned and others who believe that most are instinct. Therefore, the difference of learned and instinctive behavior is not one that can classify animals and humans.


(1) 1) Encyclopedia Britannica Homepage , an online reference guide

(2) 2)Nobel Peace Prize Homepage , an autobiography on Konrad Lorenz

(3) 3) Microsoft Encarta 2000 "Animal Behavior."

(4) 4) Flexnar, Stuart Berg ed. The Random House Dictionary of English Language, 2nd Unabridged ed. "will," Random House: New York. 1987.

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