Animals in Translation (12 page)

That would make a difference in the open arena test because fear and aggression are related. Most of the time, the more fearful an animal the less aggressive he is, because a high-fear animal is afraid to get into a fight. High-fear animals can also be more aggressive under certain circumstances, which I'll get to in a second. But overall, fear inhibits aggression.
Under most circumstances,
rats who bite are probably less fearful, so at the first lab, the one with the hypothetical lady culling the biters, I'm selectively breeding for fearful rats, and that's what I'm getting. Rats with higher fear.

That's one possibility.

On the other hand, say it was the macho guy who was culling the aggressive rats, not the lady. Maybe he was handling his rats roughly and scaring them. If that were the case, the rats doing the biting would be the high-fear rats, not the low-fear ones. Low-fear animals are more aggressive when fighting another animal, but high-fear animals are more likely to panic and bite when they are handled roughly by humans. If the man got rid of the biting rats he would be the one changing the gene pool by selecting for calm, low-fear animals who can take a lot of rough handling. Either way you get the same result: one lab is inadvertently breeding a different kind of rat—a more confident rat with
lower
fear, in this case.

We'll probably never know what happened, but the bottom line is that some sort of unconscious, unintentional selection pressure had to have been put on one or both lines of those rats to cause them to diverge so dramatically in just five years.

That's not a bad thing on the face of it necessarily, because accidental selection pressure is
probably
less dangerous to the animal, although that's never been studied. At least with unconscious selective breeding the humans influencing evolution aren't consciously trying to change
just one aspect of the animal.
They may be unconsciously shaping a cluster of related behaviors, or they may just be less intense about changing the one behavior (like biting) that's bothering them. The lady at lab number one might not be culling every single rat who shows the tiniest bit of aggression, so the gene pool doesn't get quite so distorted as it does in formal selective breeding programs.

It's when you consciously and purposely breed animals to change one defined physical trait dramatically from what nature intended that you can definitely end up with some major emotional and behavioral problems. Moreover, when you're trying to change a physical trait you very, very often end up changing an emotional and behavioral trait, too. The body and the brain aren't two different things, controlled by two completely different sets of genes. Many of the same chemicals that work in your heart and organs also work in your brain, and many genes do one thing in your body and another thing in your brain. So if you change a gene in order to change a chicken's breast size, you're also going to change whatever that gene might have been doing in the chicken's brain, assuming you're modifying a gene that is active in both places.

This is a very serious problem in the selective breeding of animals. Over the years I have learned that when you over-select for any trait at all, eventually you get neurological damage, and neurological damage almost always means emotional damage, or at least important emotional changes. The distressing thing is that with single-trait breeding for a physical trait, nobody notices the emotional changes that are emerging right along with the altered physical trait, because
nobody is expecting to see any emotional changes.
The breeders are monitoring physical changes, not looking for emotional or behavioral changes. So breeders don't perceive how much the animals are changing emotionally until the behaviors have gotten so extreme that the alarm bells finally go off. Then they've got another big problem to fix.

With the rapist roosters, the good news is that I think they probably are getting the problem fixed now. I saw some of these chickens just a few months ago, and they all behaved just as nicely as can be. I think probably the companies are culling the rapists, but I don't know for sure, since they don't write up and publish what they're doing.

P
SYCHO
H
ENS

There was another really bad case of warped evolution with egg-laying hens up in Canada. White chickens are much more hyperactive and frantic than brown chickens, who are calm and laid-back. However, white chickens have a big advantage over brown chickens, which is that they need a lot less food to lay the same number of eggs. That's called
feed conversion.
The farm I visited wanted to breed brown chickens who could lay more eggs on less food, so they crossed them with the more feed-efficient white chickens. (They didn't want to just switch over to white chickens, because a lot of people like to eat brown eggs and only brown chickens produce brown eggs.)

In the succeeding generations some chickens were still almost solid brown, some had brown and white feathers mixed together like a tweed, and others were mostly white. The brown chickens had mature feathers, but the feathers on the white chickens were immature, soft, and runty. The central spine of each feather was short, soft, and limp, and the feather
barbs
(that's the feathery stuff that grows out of the shaft) were super-soft, almost like down.

Emotionally, the brown hens were the calmest birds, the brown and white hens were nervous, and the white hens were extremely anxious and agitated. When you walked into the barn they would go berserk squawking and hopping up and down. They were extremely hyperactive and frantic-acting. Then when they got old they'd start beating their own feathers off against the sides of their cages, until they were half nude. They were violent, too, and would peck and kill each other if they had a chance.

But nobody did anything about it because it was another case of
the change happening slowly enough that the humans adjusted to the new chicken reality and perceived it as natural. The bad became normal. Finally one farmer bought some brown Hutterite chickens that they housed close to the white chickens, and the difference jumped out at them. The brown chickens could lay as many eggs as the white chickens, although they needed 10 percent more feed, but they were calm birds who didn't show any signs of agitation or anxiety. When they got old they still had all their feathers.

In the hens' case I think the reason for their psychological problems is less mysterious than whatever caused the roosters to become violent rapists.
Pure
white animals (and people) have more neurological problems than dark-skinned or dark-furred animals, because melanin, the chemical that gives skin its color, is also found in the midbrain, where it may have a protective effect.
¹
You see all kinds of problems in white animals. Dalmatians with the highest ratio of white fur to black are getting close to true albinism. They're more likely to be deaf than other dogs, and they are often airheads you can't train. Black-and-white paint horses can have problems, too. It's not unusual for a paint horse to be plain crazy, especially if he has blue eyes.

You see quite a few problems in animals with blue eyes. I met a paint horse once who had one brown eye and one blue eye, and he clearly had a horse version of Tourette's. Every sixty seconds his whole body would flinch uncontrollably. And it's fairly well known that if you mate two blue-eyed huskies the offspring can have problems.

The color of the animal's skin is more important than the color of its fur. If its skin is dark, that's good. The inside of a dog's mouth should be mostly black, with some white.

True albino animals are much worse. A study by Donnell Creel, research professor of ophthalmology and visual sciences at the University of Utah, looked at all the problems and differences in albino animals, and concluded that researchers should not be using albino animals in their research, because albino animals are not normal. Albino animals like the white laboratory rats people used for years probably aren't even good for drug research, because melanin binds to some of the chemicals used in medications, so an albino animal's
response to a medication can be completely different from a non-albino animal's.
²

In the wild there are very few all-white animals apart from polar bears and the occasional white wolf. But polar bears and white wolves both have dark skin; it's just their fur that's white. They aren't albino. It's when the skin is all pink or all white that the animal has problems. Albino animals are occasionally born in nature, but their survival rate is low because of all their problems. I am definitely against humans doing things like deliberately breeding albino Doberman pinschers because they look so pretty. These animals are not normal, and they suffer. People who own albino Dobermans report that their dogs have poor vision, intolerance to sunlight, skin lesions, and problems with temperament, usually aggression. In one survey 11 percent of owners said their dogs had bitten people.
³
That's an enormously high number considering how rare dog bites are in comparison to the number of dogs living with humans.

So it's not surprising that an all-white chicken would have a lot of emotional problems, though we don't know why breeding a chicken to need less food would turn her feathers and skin white in the first place. How is feed conversion related to feather color? We don't know, and we could probably learn a lot about the biology of emotions if we studied the unintended behavioral changes that have come out of these selective breeding programs.

Whenever I talk about white animals in my lectures, people want to know whether what I'm saying applies to white and black people. The answer is that it doesn't, because white people aren't really white. White humans have melanin in their skin, and get tan when they spend time in the sun. Caucasians' skin color evolved the same way everyone else's skin color evolved, through the forces of natural selection operating without conscious human interference. That's why you see emotional and behavioral differences in all-white animals that you don't see in “all-white” people.

Nature doesn't evolve a Dalmatian. The Dalmatian has been artificially bred to be mostly white, and is starting to be closer to albinos than to normally pigmented animals. It's not an albino, but it's getting there.

H
OW
P
EOPLE
C
HANGE
A
NIMALS
' E
MOTIONS

So far I've been talking mostly about accidental changes that come out of single-trait breeding programs, but people also change animals all the time in a much more natural way. That happens because people are in charge of domestic animals' lives, and we make or influence the decisions about which animals get to reproduce and which animals don't.

A lot of the time—maybe even most of the time—these changes aren't bad at all. Some of the changes might even be good. Here's an example. Several years ago I visited the pigs at two
multiplier units
within the same company but located in different parts of the country. A multiplier unit is a breeding colony that raises female pigs to sell to farmers. The pigs all belong to the same genetic line, and are very close to each other genetically because breeders use a fair amount of inbreeding to keep consistency in the animals. The pigs in these two units started out the same in every way, genetically, physically, and emotionally.

But by the time I saw them, the pigs at the two units had developed completely different personalities. The pigs at one of the multipliers were much more excitable and hyper, while the pigs at the other one were calm and easygoing. It was the same story as the rapist roosters: none of the humans had any idea they'd evolved a whole new pig. They never visited each other's farms, so they didn't know the pigs' personalities had diverged. That's what I mean by
natural
—nobody was doing anything on purpose to affect the pigs' evolution. It just happened.

When I took a look at the pigs' lives in the two units I found the cause: the unit with the calm pigs had been selecting for placid temperaments unknowingly. In a multiplier unit each female pig has to be individually evaluated for breeding stock. The employees weigh her and look at her teeth, her udder, and the overall
conformation
of her body. Conformation means that the different parts of the animal are in good proportion to each other. The only difference between those two units was that one unit had a good, stable scale and the other unit had a crappy scale with a needle that jumped all over the place. The unit with the crappy scale couldn't get a reading
on the more hyper pigs, and I'm sure they were culling the hyper ones and keeping the calm ones.

They didn't have a conscious
plan
to cull the hyper pigs; they just ended up doing it “naturally” because the scale was defective. Since the farm with the good scale could get reliable weights on all the pigs whether they stood still or not, there was no accidental selection pressure to get rid of the hyper ones. That shows you how sensitive animal genetics is to the environment: something as simple as how well the scale is working at a multiplier unit can change a pig's inherited emotional makeup.

Accidentally shaping a pig's genetics to create calmer animals is an example of a “natural” human selection pressure that's not only harmless but might be good for the animals. People and domestic animals have been together for a long time, and domestic animals have been evolving in response to humans for years. A pig wouldn't be a pig if it
hadn't
been evolving in the company of humans. He'd be some other kind of animal, like a wild boar. So probably a lot of the
incidental
selection pressures we put on animals are either harmless or good for the animal.