Critical Reasoning—on Aggression and Dominance

Dogs Head-To-Head

Is this head-to-head confrontation a display of aggressive or dominant behavior? We need good definitions to decide correctly for one or the other.

In the following, I will give you four definitions of aggression and dominance; and will analyze them determining whether and why they are good or bad definitions.

Behavior is tricky to study because it is highly dynamic depending on many variables. It is even more difficult to describe because nothing, or very little, is as clear cut as we would wish and our brains strive after. The difference between any two behaviors is like the difference between any two colors in the light spectrum. When is red not red but yellow is as difficult to assert as when friendly behavior turns into pacifying, pacifying into submissive, or submissive into fearful. It is, ultimately, a question of definition and convention.

Behavior and emotion are closely connected and yet we can only see the former and guess about the latter. Generalizations are troublesome and prone to error. These inherent difficulties combined with poor definitions and a sloppy use of the terms can only turn a difficult subject-matter into a nearly impossible one. My suggestion to attempt to remedy this is to formulate accurate definitions, to apply terms consistently, and to be modest in our claims and generalizations, leaving plenty of room for alternative hypothesis and improvement.

I will exemplify the problem with some representative statements about dominance and aggression, which I picked from articles on the Internet. The name of their authors is irrelevant in this context because my purpose is not to criticize single persons, only to point out fundamental errors and to help my readers to analyze what they read, to find their bearings, and develop their own educated opinions.

In all fairness, we must appreciate the problem any author faces when attempting to describe an everyday occurrence like behavior accurately, and living up to a scientific standard, an occurrence which we are used to registering, describing and conveying in daily language. It’s much more difficult than to write a mathematical sentence. “Between a rock and a hard place,” the author tries not to use too many technical terms, which require definitions on their own, putting him or herself at the mercy of everyday language and colloquialisms bound to a myriad of interpretations and misinterpretations. If you’re the author of one of the analyzed statements below, please regard my analysis as an aid. I’m definitely on your side, fully appreciating the burden of the task you so bravely undertook: to define and to explain.

Example 1: “In animal behavior, dominance is defined as a relationship between individuals that is established through force, aggression and submission in order to establish priority access to all desired resources (food, the opposite sex, preferred resting spots, etc). A relationship is not established until one animal consistently defers to another.”

The author states that dominance is one kind of relationship: (“dominance (…) is a relationship”) with the function to “(in order to) establish priority access to all desired resources.”

The statement doesn’t tell us explicitly what dominant behavior is, but leaves us guessing that since dominance “is established through force, aggression and submission,” it must be related to these behaviors; but it doesn’t define aggression and submission, which are technical terms.

The statement seems either biased or too restrictive. One individual can establish a dominant (priority access, according to the author) relationship with another through motivation, persuasion, argumentation, bluffing, bribing, all without the use of force or aggression (aggressive behavior), independently of how we exactly understand these terms.

Most social parents establish their dominance status over their offspring not by using aggressive behavior, but because they are better (older, more experienced) at solving problems (this is persuasion and argumentation) or only a limited and inhibited amount of force, which is quantitatively and functionally so different from aggressive behavior, that it deserves a new name (dominant behavior).

In some cases and for many reasons, most commonly age and experience, it is even the lower ranking (in need of protection) that bestows a higher ranking to the other (it’s a “you decide”). Aggressive behavior and dominant behavior are, thus, not the same.

hierarchy maintained by means of aggressive behavior tends to be unstable, either because some of the lower-ranking leave the group (estimating that the costs of group membership out-value its benefits), or because they constantly challenge the higher ranking. Any hierarchy maintained by means of dominant behavior tends to be more stable because the lower ranking individuals have greater benefits at relatively low costs.

The sentence “to all desired resources,” is too daring. I wouldn’t dare say all and I doubt very much that any individual ever controls all desired resources (depending on the number, of course, but all suggests many). No hierarchy is ever more consistent than it is regularly subject to changes. Even in established hierarchies, the highest ranking individuals do not always gain access to particular resources on particular encounters. Persistent dominant behavior from one individual toward the same other individual tends to turn their relationship hierarchical, but it has to be maintained by regular displays of dominant behavior.

The sentence is not a definition of dominant behavior because to be so we’d have to substitute dominance with dominant behavior and aggression with aggressive behavior, and we would get “dominant behavior is established through aggressive behavior,” which doesn’t explain anything.

If dominance and aggression are the same, there is no need to call it something else: aggression would do. The term submission seems misplaced: “dominance is established through submission” is a contradiction since one is the antonym of the other. The sentence doesn’t seem to make sense once we begin analyzing it, but I have a hunch of what the problem is: the author is confounding hierarchy with dominance. If we substitute one term by the other, then the sentence makes sense—a relationship can be hierarchical—though, it is still wrong because a hierarchical relationship does not necessarily involve force and aggressive behavior; it can involve many other aspects as we saw.

The sentence “A relationship is not established until one animal consistently defers to another,” can be misleading. It gives the impression that no relationship at all exists between two individuals unless one consistently defers to the other, which is not true. There are many examples of relationships, most as a matter of fact, be it between humans, wolves or dogs, where one of the parties does not consistently defer to the other. Quite the contrary, in most stable relationships, both parties consistently defer to one another.

In the statement above, and in general, we confound dominance with dominant behavior; we confound a defining characteristic with an attribute.

A dog is not dominant as it is black or short-legged. A dog shows dominant behavior toward (condition 1) when (condition 2).

“A knife is a cutting tool” indicates a defining characteristic (permanent). “This knife is sharp” indicates an attribute (temporary). The correct is: “This knife is sharp to cut meat (=condition 1) today (=condition 2).”

Likewise, “Bongo is dominant toward Rover (=condition 1) when they find a bone (=condition 2).” More correctly, we should write “Bongo showed today dominant behavior toward Rover when they found a bone.” We can also say, if it is the case, “Bongo shows, more often than not, dominant behavior toward Rover when they find an edible item”.

This is characterizing the behavior, not the individual. What we cannot say is “Bongo is dominant, Rover is submissive” because these are not defining characteristics of an individual.” These are attributes of their behavior under certain conditions even when these conditions seem to be rather encompassing.

Bottom line: The statement is not good because: (1) it defies observational data (aggression is not a necessary condition in a dominance relationship), (2) if aggression is a necessary condition, then we don’t need to call it dominance, we can simply call it an aggressive relationship (or antagonistic if you prefer a nicer name), (3) it is too restrictive (‘all desired resources,’ ‘a relationship is not established,’ ‘consistently defers’).

Let me give you another example of a representative sentence, this time about aggression, taken from another article on the Internet.

Example 2: “So what causes aggression? Aggression is a response to something/someone the animal perceives as a threat. Aggression is used to protect the animal through the use of aggressive displays (growling, barking, tooth displays, etc.) or protect the animal through aggressive acts (biting). Aggressive behavior is most frequently caused by fear.”

We miss the definition of “threat” to be able to analyze the sentence conclusively, but assuming that threat means “an intention of imminent harm, danger, or pain” (The Free Dictionary), the statement is false.

A threat is only a threat if it threatens, that is if it succeeds in eliciting fear behavior (apprehended as imminent danger). Otherwise, if the threatened individual does not consider itself under imminent harm, danger or pain, then it is not a threat, it is just an exclamation (information).

Animals respond to threats (not exclamations), which are aggressive behaviors, by either neutralizing the opponent’s aggressive behavior (pacifying behavior), giving up (displaying active or passive submissive behavior), or fleeing (the most effective energy saving measure when seriously threatened). When threatened, attacking would be the worst possible strategy. If attacking solves the problem, then the threat was not a threat at all (by definition) because it was not dangerous enough to qualify as such.

The only occasion when some animals respond aggressively to threats (not all, some freeze and die) is when pacifying behavior, submissive behavior, and fleeing doesn’t have the desired effect of neutralizing the threatening (aggressive) behavior of an opponent. These are exceptional exceptions.

The sentence “Aggression is used to protect the animal through the use of aggressive displays (…)” is circular. Aggression being synonymous with aggressive behavior and display and act with behavior means that the sentence reads “Aggressive behavior is used to protect the animal through the use of aggressive behavior or protect the animal through aggressive behavior.”

Furthermore, since the author writes in the passive, it leaves us with the feeling that aggression is some mysterious quality. Who uses it? Where does it come from? Re-writing it in the active, we get the even more nonsensical “The animal uses aggressive behavior to protect itself through the use of aggressive behavior or protect itself through aggressive behavior.” This is not exactly a statement likely to enlighten anyone, quite the opposite.

The sentence “Aggressive behavior is most frequently caused by fear” is the result of our use of terms without having given enough thought to their proper definitions. Fear does not elicit aggressive behavior. It would have been a lethal strategy that natural selection would have eradicated swiftly and once and for all. A cornered animal does not show aggressive behavior because it is fearful. It does so because its natural responses to a fear-eliciting stimulus (pacifying, submission, flight) don’t work. 

Let us find out why a third statement, which I also took from the Internet, is much better than the two that we have analyzed above.

Example 3: “Dominance is not a personality trait but a description of a relationship between two or more animals and is related to which animal has access to valued resources such as food, mates, etc.” We can easily improve this statement by avoiding the unclear “is related to” and the passive construction of the sentence: “Dominance is not a personality trait but a description of a relationship between two or more animals; in a dominance relationship, the dominant animal has access to valued resources such as food and mates.” (We also drop the vague and unnecessary “etc.”).

This statement is not as restrictive as the first one we analyzed. For example, it does not claim aggressive behavior as a necessary condition. It allows for more options. It also says what the term being defined is not (“not a personality trait”).

The art of making a good definition is to find the right balance between too much and too little and to state only the absolutely necessary conditions. A too restrictive definition has fewer chances to be adopted than a broader one, and a too broad definition risks losing its defining function. This definition of dominance is more likely to be accepted and adopted by a larger number of people than the first one.

A proper definition defines exactly what is supposed to define and nothing else. A good definition gives an if-and-only-if condition for when an object or a term satisfies the definition. It is conclusive and exclusive. A good definition should also involve simpler terms than what we are defining.

Sometimes, we are compelled to use working definitions. A working definition is a definition we choose for an occasion and may not fully conform to the established definition. It is a definition at a stage of being developed.—a tentative definition that in due time may turn into an established definition.

Dogs Pacifying Behavior

Believe or not, the higher ranking (ethology term) or most distinguished (in human terms) dog is the one on the right. That is the function (and the beauty) of the evolutionarily stable strategy dominant/submissive behavior (when defined correctly). It resolves a confrontation without injury to either party, spending only a manageable amount of energy. The dog on the left shows pacifying behavior, which is a voluntary display of a mild form of submissive behavior. It’s politeness, recognition, in human terms.

Example 4: “Dominant behavior is quantitative and quantifiable behavior displayed by an individual with the function of gaining or maintaining temporary access to a particular resource on a particular occasion, versus a particular opponent, without either party incurring injury. If any of the parties incur injury, then the behavior is aggressive and not dominant. Its quantitative characteristics range from slightly self-confident to overtly assertive.”

This is a good definition because it defines a term including and excluding the necessary conditions. It defines something concrete and observable, not a semantic form (it’s easier to define “dominant behavior” than “dominance relationship”).

It states a necessary condition to distinguish it from a related technical term, aggressive behavior, even explaining a defining characteristic of the latter.

It does not include other terms needing a definition. It includes enough conditions to justify the use of the term, not too few to risking being synonymous with another term, and not too many to risking losing its explanatory value by being too encompassing.

It gives an example of its main characteristic in plain words. It does not presuppose any special knowledge of a reader to understand it. It’s almost impossible not to agree with this definition unless, of course, one wants the term to describe something completely different (which is another matter altogether).

It is not likely that we’ll find the truth, the only truth and nothing but the truth about behavior anytime soon, if ever, but I believe we can come closer to it by being meticulous in our observations, strict in our argumentations, modest in our generalizations, and prudent in our conclusions.


"Ethology" by Roger Abrantes

If animal behavior fascinates you, you will enjoy "Ethology—The Study of Animal Behavior in the Natural Environment," the book and course by ethologist Roger Abrantes.
Enrolling for this course puts you in direct contact with the author to whom you can pose any question while you complete your coursework. Click here to read more and enroll.

Aggressive Behavior—Inheritance and Environment

Dog Aggression 5.

These two dogs are both equally self-confident (showing equal dominant behavior). Any aggressive behavior deriving from this situation will not be reactive-impulsive, but instrumental (photo from dog


In an earlier blog, we dealt with the definition of aggressive behavior. Today, we will analyze types of aggressive behavior and their correlation with genetics. Even though we came up with a strong definition of aggressive behavior, we should not think that all matters are resolved. In the following, to make it shorter, we will use aggression and aggressive behavior interchangeably. When studying human aggression, it is common to subdivide it into two types: (1) instrumental aggression, which is purposeful or goal-oriented; and (2) reactive-impulsive aggression which is elicited by loss of emotional control and often manifests itself as uncontrollable or inadequate actions.

Let us note that, “Aggression differs from what is commonly called assertiveness, although the terms are often used interchangeably among lay people (as in phrases such as ‘an aggressive salesperson'” in Quadri and Vidhate’s words. They also state, “Predatory or defensive behavior between members of different species may not be considered aggression in the same sense.” I would go a step further and claim that these are not to be considered aggressive behavior in any sense.

Dog Aggression 7.

This dog shows self-confident (dominant) aggressive behavior. This is instrumental aggressive behavior (photo from dog-adoption-and-training-guide).

A distinction in types of aggressive behaviors is between (1) pro-active (also controlled and instrumental) and (2) reactive-impulsive. The former is not an end in itself, only the means to achieve a goal. There are no strong emotions involved. On the contrary, its effects depend on calculated and well-timed action. The latter has no goal in itself and is marked by intense emotions. In short, researchers of aggressive behavior in children have found it useful to distinguish between reactive (impulsive) from proactive (instrumental) aggression.

Modern frustration-aggression theory claims that anger is a reaction to an aversive experience, including frustration. It emphasizes the importance of moral violation as justifying the expression of aggressive behavior.

The question is whether we also find these tyes of aggressive behavior in other animals than Homo sapiens sapiens. Being an evolutionary biologist and a good Darwinist, you know that I am always extremely suspicious of any statement claiming that any trait is only found in one single species. The odds of that happening are worse than of winning the big lottery.

Dog Aggression 8.

This dog shows insecurity and aggressive behavior. This may be reactive-impulsive aggressive behavior, but may also be learned behavior (photo by

Do animals other than humans have morality and will they fight for a cause? This is a difficult question because as far as I am concerned, I cannot envisage any way of verifying it. In that sense, some would even call it a meaningless question. Let us analyze the evidence we have. We have evidence that some animals show empathy and altruism, widely recognized as conditions for morality. Shermer points out that humans and other social animals share the following characteristics: “[…] attachment and bonding, cooperation and mutual aid, sympathy and empathy, direct and indirect reciprocity, altruism and reciprocal altruism, conflict resolution and peacemaking, deception and deception detection, community concern and caring about what others think about you, and awareness of and response to the social rules of the group.”

However, we can account for all these characteristics in terms of evolutionary costs and benefits and using models based on evolutionarily stable strategies. We don’t need to invent a new term, morality, to explain that. Therefore: if humans show moral behavior, so do other species albeit differently. What we might need to concede is that sometimes quantitative differences amount to a qualitative difference, and hence humans showing these traits in such a high degree justifies us coining a new term, morality.

Dog Aggression 9.

This dog (to the right) shows learned aggressive behavior. It may be impulsive-reactive, but it does not need to be (photo by

If that is the case (and I’m only theorizing), it makes sense to label some human behavior as moral, and to disregard the possible morality in other animals (unless new discoveries enlighten us differently).

If it does not make sense to analyze the behavior of other animals than humans in terms of morality, then it follows that we can as well neglect reactive-impulsive aggression caused by violation of moral rules in those other animals.

However, we cannot dismiss the same behavior caused by loss of emotional control because other animals than humans can also lose control over their emotions. The difficult part here is, as always, the term emotion, which is vague and, therefore, one that biologists prefer to do without.

What is an emotion? According to Schacter, an emotion is a “[…] a positive or negative experience that is associated with a particular pattern of physiological activity” caused by hormones, neurotransmitters, dopamine, noradrenaline, serotonin and GABA. We find all these in some animals other than humans; therefore, if we can accept the above definition of emotion, we must concede that if we can show emotional behavior, so can they.

The only way in which it makes sense when dog people speak of dogs being reactive (meaning they growl or bite someone) is this: those dogs display reactive-impulsive aggressive behavior. It is still by all means aggressive behavior, just one type that may or may not exist in some considerable degree in other animals than humans depending on whether I am right or wrong in my theorizing.

Recognizing and identifying reactive-impulsive aggression correctly may be advantageous because research shows that it may be easier deterred than instrumental aggressive behavior. Reactive-impulsive aggression appears to result from a distorted perception of competition, not realizing that there are evading routes, and enhanced by the inability to control the associated emotions. There is also evidence that reactive-impulsive aggression (contrary to instrumental aggression) is related to low levels of serotonin in the brain. On the other hand, classifying all canine aggressive behavior as reactive-impulsive, as it seems to be the practice these days, may be a fatal mistake with extremely severe consequences.

A dog displaying aggressive behavior can show it self-confidently (what we, ethologists, call dominant behavior) or insecurely (showing submissive behavior—not fearful). The former is excluded from being reactive-impulsive—it is instrumental and goal-oriented. The latter may be if the dog does not realize that a clearer display of submissive behavior or flight would solve the problem. This kind of aggressive behavior may be: (1) the consequence of poor imprinting and socialization (the dog simply didn’t learn how to solve social conflicts), (2) the result of inadvertently reinforced behavior. Dog owners reinforce their dog’s reactive-impulsive aggressive behavior attempting to do what they call ‘calming down the dog.’ The dog growls, they say, “quiet ” (or similar), the dog looks at them, and they reinforce that with a treat and a “good job.” It doesn’t take many repetitions for the dog to learn that displaying aggressive behavior provides it with attention and food.

The term reactive does not belong to ethology, which classifies behavior by function. I don’t know how it came into dog training, but I suspect a psychologist introduced it and people liked it because apparently it sounded better to say, “My dog is reactive” than “My dog shows aggressive behavior.” Ironically, the term places the full responsibility for the unwanted behavior on the owners—reactive-impulsive aggression is either the result of poor imprinting/socialization or of inadequate training.

Is aggressiveness inherited?

Heritability studies attempt to determine whether a trait passes from parent to offspring. Some genetic lines in many species of birds, dogs, fish, and mice seem to be more prone to aggression than others. Through selective breeding, we can create animals with a tendency to show more aggressive behavior.

Some aggressive behavior is evolutionary advantageous, and some is not and may be an impediment to social cohesion. Maynard Smith says that it is not surprising for aggressiveness to have a strong genetic correlation given the high likelihood of both potentially positive and negative selective discrimination throughout evolution.

Research has uncovered many factors that contribute to aggressive behavior. Disruption of the serotonin system is a highly significant feature in predisposing aggression. There is a correlation between testosterone levels and aggression. Extremely low levels of blood sugar (hypoglycemia) may elicit physiological changes and aggressive behavior.

Most researchers agree that we must consider the influence of genes, not in isolation, but as functioning in the whole genotype, as well as the effect of the environment. Future research in the genetics of aggressive behavior may very well focus on epigenetic factors.

Doubtless, most behavior traits, except simple reflexes, contain a genetic plus an environmental component. No behavior will develop without the appropriate genetic blueprint and no behavior (again except for a few simple patterns) will show in the absence of the right environmental stimuli.

It is probable that each individual filters and selects stimuli from a wide range in its habitat according to its genetics, thereby creating its uniqueness of experiences. As Bock and colleagues say, we create our own environment. I have no reason to suspect that the same does not happen with other animals.



Akert, R. M., Aronson, E., & Wilson, T.D. (2010). Social Psychology (7th ed.). Upper Saddle River, NJ: Prentice Hall.
Blair R. J. R. (2004) The roles of orbital frontal cortex in the modulation of antisocial behavior. Brain Cogn 55:198–208.
Bock, Gregory R. and Goode, Jamie A. (eds.) (1996). Genetics of Criminal and Antisocial Behavior. Chichester: John Wiley & Sons.
Craig, I. W., Halton, K. E. (2009). Hum Genet (2009) 126:101–113.
Javeed, Q. S. and Vidhate. N. J. (2012). A Study Of Aggression And Ego Strength Of Indoor Game Players And Outdoor Game Players. Indian Streams Research Journal, Volume 2, Issue. 7, Aug 2012.
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"Ethology" by Roger Abrantes

If animal behavior fascinates you, you will enjoy "Ethology—The Study of Animal Behavior in the Natural Environment," the book and course by ethologist Roger Abrantes.
Enrolling for this course puts you in direct contact with the author to whom you can pose any question while you complete your coursework. Click here to read more and enroll.

Aggressive Behavior—the Making of a Definition

Contrary to what you might suppose, aggressive behavior is difficult to define. “Lack of agreement regarding definitions of aggressive behavior has been a significant impediment to the progress of research in this area,” writes Nelson in 2005 in his big book ‘Biology of Aggression.’

Why is a good definition necessary? Because only then do we know what we are discussing.

I have never been quite satisfied with my own definition, and it nags me, worse than a mosquito bite, when I can’t come up with a good definition. I have often returned to it changing a comma or two to see if it improved. Alas, to no avail, updated versions were marginally better, but not resoundingly so.

Aggression 02

Aggressive and dominant behavior (erected ears, short mouth, big eyes) (picture dogsquad).

My original definition, let me remind you, was: “Aggressiveness (or aggressive behavior) is behavior directed toward the elimination of competition. It can range from displays of intent, like growling, roaring and stamping to injuring behavior like biting, staging, kicking.”

Not bad, but could be better. I checked many other definitions to analyze their strengths and shortcomings, hoping to get the necessary inspiration to come up with a really good definition.

A— “Aggressive behavior is behavior that causes physical or emotional harm to others, or threatens to. It can range from verbal abuse to the destruction of a victim’s personal property.” ( Not bad, but not precise enough to use in the biological sciences.

Aggression 02

Aggressive and submissive behavior (not fearful). This is the behavior a cornered dog shows when pacifying, submission and flight don’t work (picture from doggies).

B— “Aggression is a forceful behavior, action, or attitude that is expressed physically, verbally, or symbolically. It may arise from innate drives or occur as a defense mechanism, often resulting from a threatened ego. It is manifested by either constructive or destructive acts directed toward oneself or against others (Mosby’s Medical Dictionary, 8th edition).” Not bad either, though weakened by the passive voice. It recurs to terms needing strong definitions as well, i.e. drive, defense mechanism. Finally, it is a bit too psychological for the evolutionary biologist—what is a threatened ego?

C— “Aggression is behavior that is angry and destructive and intended to be injurious, physically or emotionally, and aimed at domination of one animal by another. It may be manifested by overt attacking and destructive behavior or by covert attitudes of hostility and obstructionism. The most common behavioral problem seen in dogs.” ( This one is not good. It is more a list of synonyms (angry, destructive, hostility, obstructionism) than a definition. It mixes concepts together too easily (aggression and domination?). Finally, the most common problem in dogs in our files (over 10,000 of them) is home alone problems, not aggressive (whatever that is) behavior.

D— “Aggressive people often uses angeraggressive body language […] “( This one, we won’t waste any more time with. A definition that uses the definiendum is not a definition.

Aggression 03

Aggressive and submissive behavior (ears down, long mouth, smaller eyes) (picture Cesar’sWay).

E— Aggression is a response to something/someone the animal perceives as a threat. Aggression is used to protect the animal through the use of aggressive displays (growling, barking, tooth displays, etc.) or protect the animal through aggressive acts (biting). Aggressive behavior is most frequently caused by fear.” (somewhere on the Internet). This one is not good either. Again, it uses the definiendum in the definition. We miss the definition of threat to be able to analyze the sentence conclusively. More seriously, it states that aggression is caused by fear, which from an evolutionary point of view doesn’t make sense. Fear does not elicit aggressive behavior. It would have been a lethal strategy that natural selection would have eradicated swiftly and once and for all. A cornered animal does not show aggressive behavior because it is fearful. It does so because its natural responses to a fear-eliciting stimulus (pacifying, submission, flight) don’t work. 

Aggression 04

Growling and snarling are also aggressive behaviors (picture askmen)

F— “Aggression is defined as behavior which produced or was intended to produce physical injury or pain in another person.” (Nelson, R. .J. 2005. Biology of Aggression. Oxford Univ. Press). This is a much better definition, but it could be more explanatory.

So, after yet another round of deliberation, here follows my suggestion.

“Aggressive behavior is behavior directed toward the elimination of competition from an opponent, by injuring it, inflicting it pain, or giving it a reliable warning of such impending consequences if it takes no evasive action. It is distinguishable from dominant behavior in as much as the latter does not include harmful behaviors though it may require some degree of forceful measures. Aggressive behavior ranges from reliable warnings of impending damaging behavior such as growling, roaring, and stamping, to injurious behaviors such as biting, staging, and kicking. Predatory behavior is not aggressive behavior.”

This is much better than earlier versions, and it complies with all the requirements for a good definition. It defines something concrete and observable. It states a necessary condition to distinguish it from a related technical term, dominant behavior, even explaining a characteristic of the latter. It does not include other terms needing a definition. It includes enough conditions to justify the use of the term, not too few to risk being synonymous with another term, and not too many to risk losing its explanatory value by being too encompassing. It gives examples of what is and is not aggressive behavior. It does not presuppose any special knowledge of the reader to understand it.

This is a good definition because it defines the term, including and excluding the necessary conditions. Whether it will be the last word on the matter is another story. I’m sure it won’t. There is always room for improvement. A good definition must also be able to accept reviews imposed by newer discoveries. Until then, I’m happier with this one than with any earlier versions. Aren’t you?


"Ethology" by Roger Abrantes

If animal behavior fascinates you, you will enjoy "Ethology—The Study of Animal Behavior in the Natural Environment," the book and course by ethologist Roger Abrantes.
Enrolling for this course puts you in direct contact with the author to whom you can pose any question while you complete your coursework. Click here to read more and enroll.