Animals in Translation (22 page)

A
FFECTIVE
A
GGRESSION

Affective aggression is completely different from predatory aggression. Affective aggression is
hot
aggression; it's aggression driven by rage. Compared to predatory aggression, in affective aggression an animal's emotions are different, his behavior is different, and his body is different.

A cat whose rage circuits have been electrically stimulated assumes an aggressive posture and hisses, and his hair stands on end (that's called
piloerection,
for erection of the hair follicles). His body is aroused. His heart beats faster, and his adrenal system kicks in. Stimulate the same cat's predatory circuits and his body stays calm. Jaak Pansksepp says you see “methodical stalking and well directed pouncing,”
⁹
with no increase in stress hormones. Humans have tended to mix up these two states, because the outcome is the same: a smaller, weaker animal ends up
dead.
But predatory aggression and
rage aggression
couldn't be more different for the aggressor.

Animal behaviorists usually classify the different types of rage aggression by the stimulus that triggers the aggression, and different experts have come up with slightly different lists.

This is mine:

1. Assertive aggression. This category includes dominance aggression and territorial aggression.
   
2. Fear-driven aggression. This includes maternal aggression to protect young.
   
3. Pain-based aggression.
   
4. Intermale aggression. Intermale aggression is influenced by testosterone levels.
   
5. Irritable or stress-induced aggression. This includes
   redirected aggression,
   such as when a cat gets agitated by the sight of another cat outside but can't get to it and so attacks another cat or person inside the house instead.
   
6. Mixed aggression. For instance, fear combined with assertive aggression.
   
7. Pathological aggression.
   

Assertive Aggression

Assertive aggression includes both dominance aggression—one animal attacking another to assert or maintain his dominance in the hierarchy—and territorial aggression, which is when an animal attacks to protect his territory from intruders. Assertive aggression is probably connected to the neurotransmitter serotonin in a fairly straightforward way; the lower the serotonin, the more aggressive the animal. Antidepressants like Prozac that increase serotonin levels can reduce dominance aggression in a pet.

Unfortunately, the connection between serotonin, assertive aggression, and actual
social dominance
or
alpha ranking
within the group still has to be sorted out. There is strong evidence from colonies of vervet monkeys that the dominant animal has the
highest
levels of serotonin and the
lowest
levels of overall aggression.
¹⁰
The lowest-ranking animals show the most random, impulsive aggression, while the leaders are calm and collected and get aggressive only when they have to defend the group.

We know this from Michael Raleigh's famous study of twelve vervet monkey colonies. He and his team removed the dominant monkey, always a male, from all twelve colonies, then gave a medication that raised serotonin levels to one of the two remaining males in the colony, and a medication that lowered serotonin levels to the other. That gave them twelve subordinate males in twelve different troops who now had higher levels of serotonin than they did before, and twelve subordinate males who now had lower levels.

Every single one of the subordinate monkeys whose serotonin levels had been raised became the dominant monkey of the pair. Then, when they reversed the medications, raising the serotonin levels of the monkeys who had previously had their levels artificially lowered,
those
monkeys became dominant.

The reason this whole area is so confusing is that we're talking about two completely different fields of research. We don't know whether the people who study dominance aggression in dogs are talking about the same thing Michael Raleigh was studying in vervet monkeys. So for the time being we have to make do with the standard definition of assertive aggression I'm using here.

Fear-Driven Aggression

Fear-driven aggression causes so much violence and destruction in the animal and human worlds that I've often asked myself, What is rage for?

Why do we have rage circuits at all?

When you look at animals living in the wild, the answer is simple. Rage is about survival, at the most basic brute level. Rage is the emotion that drives the lion being gored to death by the buffalo to fight back; rage drives a zebra being caught by a lion to make one last-ditch effort to escape. I once saw a videotape of a domestic beef cow kicking the living daylights out of an attacking lion. It was some of the hardest kicking I have ever seen. Rage is the ultimate defense all animals draw upon when their lives are in mortal danger.

When it comes to human safety in the presence of animals, fear cuts two ways. Fear can inhibit an animal or a person from attacking, and very often does. Among humans, the most vicious murderers are people who have abnormally
low
fear. Fear protects you when you're under attack, and keeps
you
from becoming an attacker yourself.

But fear can also
cause
a terrified animal to attack, where a less-fearful animal wouldn't. A cornered animal can be extremely aggressive; that's where we get the saying about not getting someone's “back up against a wall.” An animal with his back up against a wall is in fear for its life and will feel he has no choice but to attack.

On average, prey species animals like horses and cattle show more fear-based aggression than predatory animals such as dogs. That shouldn't be a surprise, since prey animals spend a lot more time being scared.

I categorize maternal aggression differently from some researchers; I put it in the fear department. I think maternal aggression is fear-driven at heart because over the years I've observed that the high-strung nervous animals will
always
fight more vigorously to protect her young than will a laid-back, calm animal like a Holstein dairy cow. Many a rancher has told me that the most hotheaded, nervous cow in the herd is the one who is most protective of her calf.

Any
mother, nervous or calm, will fight to protect her baby. That's why on farms the human parents always warn their children to stay away from mama animals. But the fact that it's always the most nervous, fearful mother who shows the most maternal aggression makes me think that maternal aggression is driven by fear, even when the animal is calm by nature. When mother animals think their babies are in danger, they feel fear, and their fear leads them to attack. That's my conclusion.

This brings me to the fundamental question you have to ask yourself any time you're trying to solve a problem with aggression: is the aggression coming from fear or dominance? That's important, because punishment will make a fearful animal worse, whereas punishment may be necessary to curb assertive aggression.

Pain-Based Aggression

This one is simple and is something all humans have experienced themselves. Pain makes you mad. A person in pain will become irritable and start snapping at the people around him, but an animal can easily become aggressive. Vets have to watch out for pain-based aggression with any animal who is suffering. A dog who has been hit by a car may lash out and bite its owner due to pain. An animal who has arthritis or some other painful condition may become aggressive when the painful limb or joint is manipulated.

Intermale Aggression

Intermale aggression is linked to testosterone levels, which is why castrating a male dog can stop his fighting other male dogs. However, castration doesn't fix
dominance aggression
in a dog, which leads Dr. Panksepp to believe that intermale aggression may actually be a third form of primary aggression separate and distinct from either predatory aggression or affective aggression. Time will tell.

Irritable or Stress-Induced Aggression

Animals who live in highly stressful conditions are more prone to aggression than animals living in reasonably calm conditions. I heard about an awful case of stress-induced aggression where a Border collie ate all her puppies. Borders are a nervous, high-strung breed, and this particular collie ate her puppies after she had been taken on a long car trip and brought to a new house. Her stress levels were already very high because she lived in a dysfunctional household that included a hyperactive teenager who could never sit still, and apparently the long journey and brand-new surroundings tipped her into violent aggression against her own pups.

Even a constant relatively minor irritant like a flea infestation can trigger stress-induced aggression in an animal.

Mixed Aggression

In real life animals probably experience more than one motivator for aggression pretty often. In particular, we know that fear-based aggression and assertive aggression often co-occur in dogs. Dr. Panksepp thinks this probably happens with maternal aggression in some cases, where the mother attacks out of fear
and
out of territorial aggression. He also thinks that if intermale aggression does prove to be a distinct form of aggression, separate from the rage circuits in the brain, it probably doesn't occur in its “pure” form very often. Two males may go into a fight eagerly, like two boxers ready for the championship match, but rage probably kicks in as one or
both males start to feel frightened, frustrated, or in pain. Then you have intermale aggression mingled with potentially three different kinds of affective aggression.

Pathological Aggression

Medical conditions like epilepsy or head injury can produce pathological aggression in an animal. This is true in people, too. For instance, we know that a lot of prisoners who have committed violent crimes have had head injuries at some point in their lives.

G
ENETIC
T
ENDENCIES TO
A
GGRESSION

Some animals are genetically disposed to higher levels of aggression than others no matter what the circumstances. There are bloodlines of rare horses that have killed or injured grooms, and cattle breeders have observed that certain genetic lines of bulls are more aggressive than others. I've already mentioned the behavioral problems that crop up with single-trait breeding. The rapist roosters are the most dramatic case, but many pigs have become more innately aggressive, too. A study at Purdue University showed that pigs bred to be lean got into more fights than pigs from a fatter genetic line.

The genetics of aggression is an especially thorny issue with dogs. Most people don't want to believe that there are some breeds, like pit bulls and Rottweilers, that are more aggressive by nature. (Pit bulls aren't an established AKC breed.) Usually these folks have known or owned individual Rotties or pits who were sweet and good-natured, so they conclude that when a Rottweiler or a pit bull shows aggression the problem is the owner not the dog. But the statistics don't support this interpretation, although it's true that statistics on dog bites aren't hard and fast.

There are lots of problems with dog bite reports. For one thing, there are a few different kinds of dogs that are called pit bulls, including some purebreds like the American Staffordshire terrier and some mixed-breed dogs. Another problem: large dogs do more damage when they bite people, so they're probably overrepresented in the statistics. Also, lots of purebred owners fail to regis
ter their dogs with the AKC, so it's impossible to know exactly how many purebred Rottweilers there are in the country and compare that figure to the number of reported dog bites committed by Rottweilers.

Because dog population data is imprecise, no one can nail down
exactly
what each breed's “aggression quotient” is compared to other breeds. Still, you can get an overall picture of which breeds are most dangerous by looking at medical reports of dog bites.
On average
Rottweilers and pit bulls are so much more aggressive than other breeds that it's extremely unlikely bad owners alone could account for the higher rate of biting. And if you're looking only at anecdotal evidence, there are plenty of cases of nice, competent owners with vicious Rottweilers or pit bulls. Aggression isn't always the owner's fault. Writing about pit bulls, Nick Dodman says, “Originally bred for aggression and tenacity, pit bulls, if provoked, will bite hard and hang on, making them as potentially dangerous as a handgun without a safety lock…. they can become quite civilized, developing into loyal and entertaining companions. But the
potential
for trouble is always lurking somewhere, as a result of their genes and breeding.”
¹¹

The Monks of New Skete, the famous trainers of German shepherds in upstate New York who wrote
The Art of Raising a Puppy,
say that every breed of dog has its
freak bloodlines
that produce dogs who are much more likely to be aggressive.
¹²
Some people have always bred dogs with enhanced aggressive behavior to serve as guard or police dogs; there are also drug dealers and other unsavory types who have deliberately bred very aggressive dogs either for protection or because they're part of the illegal dog fight scene. These dogs are like a gun with a hair trigger and no safety.

As I mentioned earlier, Rottweilers and pit bulls are the worst offenders now.
¹³
But before Rottweilers and pit bulls got so popular the most dangerous breed was the German shepherd, and Chow Chows show up in dog bite studies as having a much higher
rate
of biting per dog than other breeds.