This is the fourth article in a series about animal behavior: Part I | Part II | Part III | Part IV

The fear-fight response appears last in the discussion of fear responses, even though the possibility of an animal opting for this response ranks first in most veterinarians' minds. However, it is the last option the majority of animals will choose.

Why this occurs takes us back to that inherent hard-wiring to get the job done using the least amount of energy. Unlike some people, most animals instinctively recognize that no one wins a fight. The "winner" is merely the one who loses the least.

For most animals, it's a simple question of survival. Even a minor injury may undermine an animal's ability to compete with a conspecific (member of the same species) or ward off a predator successfully until the injury heals, so animals who fight with minimal provocation are more likely to be eliminated from the gene pool.

Consequently, most frightened animals will opt for this approach only if the other options are blocked or fail.

Panic-driven fight responses are much more energy-intense than those engaged in by more confident individuals. The more vulnerable the animal and the more the animal needs to gain or retain, the more energy he or she will be willing to devote to the process.

This explains why, for example, a small older, naturally more subordinate dog whose owner inadvertently communicated to the animal that she needs his protection may growl and snap at anyone who approaches the instant the two of them enter the examination room. For the dog, the stakes are so high that anything less than a fight response would carry a greater risk to his claim of his person.

On the other hand, had this dog spent his life as a member of a free-roaming group of more physically and mentally fit dogs, the probability of his claiming any resource as valuable as a human would be so low, he probably wouldn't even try. Consequently — and unlike animals with more confidence in themselves or in their owner's ability to protect them both if necessary these fearful physically vulnerable animals may aggress more with less provocation.

In general, there are two points to keep in mind when dealing with animals who engage or could engage in panic-driven fight responses.

1. They are more easily alarmed

As mentioned, because these animals are likely to have lower stimulus thresholds, even something we consider inconsequential may set them off.

The reason many people perceive bites from dogs or cats as coming "out of the blue" or believe the aggressor was mentally deranged is because they forget the greater range of canine and feline perception compared to human. Just because we didn't see the motion or smell the scent that took these animals to their tipping point doesn't mean it didn't exist.

2. Your response matters

How much force an animal puts behind jaws (and claws, in the case of cats) depends on the amount of stimulus received from the target or the environment. When a dog or cat snaps at or actually bites a person, this unfortunately may trigger a panic-driven human fight response.

In this situation, the person may scream loudly and wildly flail at the animal while blindly pulling away. Observers also may scream or kick at or beat the animal as they attempt to pull the biting animal off the person being bitten. Driven by emotion, these people are unmindful of the unnecessary harm this can do to the targets as well as the aggressors.

In such situations, a dog that originally may have sought only to communicate her higher status by grabbing and holding a person perceived as displaying insubordinate behavior may be stimulated by these outside stimuli to apply sufficient force to puncture the skin, tear it or worse.

Further adding to the emotional mix, practitioners and their staff members may experience two additional fears that may fuel a panic-driven human fight response at these times.

One nightmare scenario involves a canine or feline aggressor who belongs to one of those people. In this case, they must grapple with what their animal's behavior says about them professionally. Whether veterinarians like it or not, many people perceive them and their employees as the ultimate authority on all things animal, and that includes behavior.

Although the second practitioner- and staff-related fear may involve their own animals, it more commonly involves those belonging to clients: what effect any bodily harm done by the aggressing animal could have on the veterinarian's or staff member's livelihood.

What would they do if they lost a finger or couldn't work for several months because of injuries caused by this animal? Dealing with thoughts of such possible consequences of animal aggression is difficult enough when all is going well and one can work through one's options rationally. When such thoughts pop into mind when facing an aggressive animal, these may further may fuel a panic-driven human fear fight response.

But of all the fear responses, a controlled fight response by a confident animal is the most unnerving for many people. These animals always remind me of people with years of physical and mental training in the martial arts.

Because of their confidence and skill, their stimulus thresholds are higher than those of more fearful animals. This may cause less fit individuals to wrongly assume they have the upper hand. However, when others exceed these animals' thresholds, they waste little energy on warning barks, growls, hisses or raised hackles. Their bites are just enough to get the job done no more, no less.

People who have observed or been the target of such displays in domestic animals often comment on the lack of emotion displayed by the aggressor before or after the event. The panicked dog that reluctantly attacks another dog or person to protect himself and his owner may then cower or show signs of guilt and remorse in response to that person's fear-based anger.

However, these confident animals calmly clean any wounds and act as if nothing unusual occurred. Particularly in pet home environments, the latter dogs' behaviors may earn them the label of "psychopaths" and far more often than not spell the end of the human-canine relationship and even euthanasia for the dog.

Given all the emotion and symbolism with which people routinely imbue their relationships with companion animals, it's safe to say every case of human-canine or -feline aggression is unique. Because of this, adding notes regarding the animal's behavior and any attempts to address it to the medical history can benefit these animals' owners, the veterinary staff and the animals themselves. Without this information, a "Watch!!!" or "Aggressive!" header in the file might be worse than useless.

In the next brief, we'll explore why this may be.