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CHAPTER 1
THE SIZE OF THE PROBLEM
WHy there's no Dr. Dolittle
Almost all animate organisms communicate with one another ... somehow.
Fireflies flash. Frogs croak. Crickets, grasshoppers, and the like rub their legs together, or against their wing cases, producing the kinds of sound known as stridulations. Birds perform songs of varying degrees of complexity. Wolves howl. Dolphins emit sonar signals; they whistle too. Some lizards inflate pouches in their necks, or change color. Gibbons engage in bizarre duets that can last for an hour or more. Apes and monkeys have a range of strategies: hoots, barks, gestures, facial expressions. Bees dance. Ants do it with chemistry. The means different species use for communication are so bewilderingly diverse and so different from one another that you might well think something pretty complex is going on.
It isn't.
A decade ago, Marc Hauser published what is still the most thorough and complete study of animal communication systems (ACSs for short; sorry about that, I loathe acronyms with a passion, but if you had to read "animal communication system" as often as I'll have to write it in the next few chapters, you'd understand — even forgive). He found that all the information conveyed by ACSs falls into three broad categories. There are signals that relate to individual survival, signals that relate to mating and reproduction, and signals that relate to other kinds of interactions among members of the same species — call them social signals. Some signals are hard to fit into a single group. For instance, a signal of appeasement, used in confrontations when your enemy looks to be winning, is on the face of things a social signal, but it could also fall under "survival" — if you don't make it, you could get killed. But no signal falls outside of those three areas. No ACS can be used to talk about the weather, or the scenery, or your neighbor's latest doings, let alone to plan for the future or recall the past.
Of course it would be an enormous benefit for any animal if it could recall the past, noting all the mistakes it had made, and plan for the future, eliminating those mistakes. Such an achievement would maximize an animal's fitness, which is biology-speak for saying the animal would live longer, have more offspring, and spread its genes more widely. And that's what evolution's about: who dies with the most kids wins. So you may well wonder why we alone have language — why we don't inhabit a Dr. Dolittle world, where we could chat with chimps, converse with cats, debate with dogs, rap with rabbits, and yak with yaks, while all these creatures did the same things with one another.
The answer is, evolution doesn't develop things just because they'd be useful for a species to have. Evolution is a minimalist. It doesn't do a lick more than it has to. And it's also limited by what it has to work with. What it has to work with are the bodily shapes and mental abilities that exist in any species at any given moment, and the behaviors that those shapes and abilities make possible. Since within any one species those shapes, abilities, and behaviors can't vary all that much, almost all evolutionary changes are gradual and small. Very occasionally there may be a tipping point, but for the most part, nature doesn't even look like it makes leaps.
So the means by which animals communicate — all the flashes, calls, gestures, and so forth I mentioned at the beginning of this chapter — are seldom if ever things that were designed from the beginning to communicate with. Rather they are modifications or stylizations or amplifications of things animals would do anyway, things that when they started out may have had little or nothing to do with communication. This was the conclusion of the earliest ethologists, scholars like Nikolaas Tinbergen and Konrad Lorenz, and though interpretations of the function and significance of ACS units have changed radically since the 1950s, our understanding of where they came from hasn't changed.
Over time, through frequent co-occurrence, these original behaviors became associated with certain situations, and hence with the kinds of messages appropriate to those situations. Their users didn't consciously mean to communicate in the way we do when we want a window closed and say, "Please close the window": ACSs aren't just a cheap substitute for language, but something entirely different. Their users, in the process of reacting to situations, provided clues as to how other animals should react in those situations; interpreting such clues correctly improved those animals' chances of survival. Thus in a confrontational situation between mammals, shrinking postures and high-pitched sounds indicate an intent to appease the aggressor. Among songbirds belonging to species that defend territory, songs of a certain type and intensity suggest willingness to combat an intruder. And so on.
This already makes language sound unlikely. The simplest and most straightforward source for it would be sounds drawn from the ACS of the last common ancestor of chimpanzees and humans. But if those sounds were anything like the sounds chimps make, the chances of modifying or ritualizing them into words, not to mention sentences, look small. And that's even before you consider problems of meaning.
To lift yourself by your bootstraps, you first have to have bootstraps.
Why other animals have so little to talk about
It gets worse. Why do ACS units contain only survival, mating, and social signals? It's because those areas and only those areas are ones where signals can significantly increase an animal's fitness.
Look at survival calls. These include predator warning calls and food calls. A predator warning call doesn't improve the survival chances of the animal that makes the call. In fact it reduces them; it calls attention to that animal, makes it stand out as a target. But it does improve the survival chances of that animal's close relatives, who carry many of the same genes. This is what biologists mean when they talk about "inclusive fitness." You don't do stuff just to increase your own chance of sending more offspring into the world — the same purpose is served if you increase the chances of your siblings or other close kin doing so.
Once it was thought that things like warning calls were entirely automatic, like the way you blink if someone pokes a finger in your eye. The poor animal saw a leopard and yelped; it just couldn't help it. Now researchers have found that animals, though unable to speak, aren't that dumb. If they're alone, they don't call. If they're not with close relatives, they're less likely to call than if they're with immediate family.
Food calls — signals that announce the discovery of food, sometimes even its kind or quality as well as its location — can again be unhelpful to the individual if it means sharing a tasty tidbit with others instead of hogging it alone. But the same standard of inclusive fitness applies: benefit your brother and you're giving your own genes, at least some of them, a boost. So all survival calls relate directly to increasing fitness.
Now take reproduction signals. These may involve advertisements of immediate availability, such as the swelling of female genitalia in some primates when they are in estrus, or they may merely announce "I am a male/female of species X." At the other extreme, they may involve elaborate courtship dances, or the construction of complex artifacts (such as a decorated bower) to attract females. The simpler signals merely ensure that the right sexes of the right species get together at the right times. Clearly, if at one time there were animals that signaled their sex and their species alongside other animals that didn't, the first lot would meet and mate oftener than the second, so eventually every member of the species would make those signals. The more complex signals indicate not only that a mate is available but suggest that a mate of the highest quality is available. As Darwin long ago pointed out, female choice — the desire of any female to secure the best breeding stock, to bag a mate that will send her genes further into futurity — forms one of evolution's most powerful engines. So again with reproduction we have a set of signals that directly increase fitness.
Finally, let's turn to social signals. These don't have to be social in the sense of friendly; they don't even have to be limited to social species. They can relate to any kind of interaction between members of the same species. Take for example solitary birds that defend a territory, perhaps with a single mate. The signals they send to discourage intruders fall into the social category just as much as more intimate signals like the "nursing poke" used by infant apes to get their mothers to feed them. While the increase in fitness that results from these signals may not always be as direct or as obvious as with survival or mating signals, it is not insignificant. The animal that makes a rival back off without having to fight avoids possible injury or death. The animal that encourages others to groom it benefits from more than the elimination of vermin. Given that the favor is returned, affiliative bonds are then established, status within the group is enhanced, access to sexual or nutritional opportunities is increased. Better living means longer living and more progeny — once more, increased fitness.
Why language is so anomalous
Now that we've established two of the most basic features of ACSs — that they grew from behaviors not originally meant for communication and respond only to situations that directly affect fitness — we can begin to realize the enormous size of the problem that language poses for the biological sciences.
People often think that the core of this problem is the uniqueness of language. It isn't. Lots of things about humans are unique: bipedalism and absence of body hair (among terrestrial mammals, anyway), the precision grip of thumb and forefinger, even the whites of our eyes. Lots of other species have unique features too: the elephant's trunk, the giraffe's neck, the peacock's tail. And the hammering of woodpeckers, the heat-sensing of pit vipers, the trap-digging of ant lions are behaviors as unique as the physical forms of elephants, giraffes, or peacocks. But no other unique feature of any species is as isolated from the rest of evolution as language is.
Bipedalism isn't all that special. Birds managed it. Kangaroos come close. Closely related apes get up and hunker around on their hind legs from time to time. Our grip differs from that of ape fingers only in its greater range and degree of control. Hairlessness is unique, in our case, only because it's lifelong; the young of many mammalian species emerge naked from the womb and only later grow hair.
Instead, let's compare another feature that's not human but is genuinely unique: the elephant's trunk. In his book The Language Instinct the psycholinguist Steven Pinker actually uses the elephant's trunk to make language seem less of an anomaly than it really is. He asks his readers to "imagine what might happen if some biologists were elephants" — as with language, some would say the trunk was too unique to have evolved, others that it couldn't really be unique at all. But unique stuff can evolve through natural selection, so Pinker insists that "a language instinct unique to modern humans poses no more of a paradox than a trunk unique to elephants."
He's wrong. An elephant's trunk results from hyperdevelopment of the nose and adjacent parts of the face in the common ancestor of elephants and hyraxes, and anatomists can point to the exact physical ingredients that went into its makeup. But Pinker doesn't tell you what ingredients went into the making of language. (And anyway, isn't it a bit weird to compare a behavior with a body part?)
Uniqueness isn't the issue. Unlikeness is the issue. And that is something Pinker, like everyone else who writes on language evolution, doesn't really tackle. For every other "unique" thing that's evolved, you can see what was there before it, what evolution had to work on in order to produce it. Not with language.
Take what looks on the face of things the best, if not the only candidate: the communication system of the last common ancestor. But to get from any ACS to language would involve two tasks, just for starters. First, evolution would have to find the raw material — some already existing behavior that could be taken and twisted and refined into an appropriate medium. Second, and this is a task orders of magnitude harder, it would have to uncouple this new system from currently occurring situations involving fitness.
That's actually three tasks in one. The system would have to be uncoupled from situations, from current occurrence, and from fitness. Let me explain.
ACS units — all the calls, flashes, and gestures that constitute ACSs — are all anchored to particular situations: aggressive confrontation, search for a sex partner, appearance of a predator, discovery of food, and so forth. They would be meaningless if used outside those situations. Language units — words, manual signs — are not. They're meaningful in any situation. If I say, "Look out, a tiger is about to jump on you," you may know I'm just kidding, but you know perfectly well what the words mean — they mean exactly what they'd mean if a tiger really was about to jump on you.
Some linguists and philosophers may still tell you that words relate directly to individual objects in the world — dogs, chairs, trees — but they don't even do that, or rather they do so only indirectly, via the concepts of these objects that we have in our minds. If I say, "Dogs bark," what actual dogs am I referring to? Big dogs? Brown dogs? The dogs down the road? Obviously not. All dogs, then? Not necessarily. I didn't say all — my statement cannot be refuted by a barkless dog. What it means is, "Dogs as a general rule bark," or "Barking is a fairly reliable sign of dogginess." Well, just point out to me "dogginess" or "dogs as a general rule." You can't; there's no such critters. We have what may be vague but are fully functional ideas of what dogs are like, and that's what we're referring to. If we want to refer to a specific dog or dogs we can't just say "dog" or "dogs"; we have to say "this dog," "those dogs over there," "the dog with the waggly tail." So in order to get to language, the reference of meaningful units — signs or words — has somehow to be shifted from concrete situations to the concepts we have of particular things in the world.
But what ACSs are grounded in aren't just any old situations. They're situations that are occurring right now, at the very moment the ACS signal is being waved or flashed or yelped. No animal can use a predator alarm call to remind its fellows about the predator that appeared yesterday, or the predator that often hangs around the water hole. No chance of an advance warning, no reprise of what went wrong last time. Each utterance of an ACS unit is tied to whatever is going on in the immediate vicinity right at that moment. Words, on the contrary, are relatively seldom used about what's going on before our eyes. We can usually see that for ourselves, so what would be the point? We still have body language; for things like showing how far we'll push a confrontation, or how strong our sex desire is, good old body language works as well for us as for any other species, often much better than words. On the other hand, with words we can do stuff way beyond the here and now. We can exchange ideas about things infinitely remote in space and time, things we may never have seen, even things like ghosts or angels that may not exist. So somehow communication has to be released from bondage to what's happening right now.
Finally, there's freedom from fitness. We have seen how the function of ACS units is to improve fitness; no unit even comes into existence unless it improves fitness in some way. Some people have conjectured that language as a whole increases fitness. Now it may well be that at some stage in evolution, ancestors of ours who had more developed language skills left more offspring than those whose skills were less developed. But though this is a plausible conjecture, there's zero evidence for it, and in any case it's a totally different issue. The point is that no ACS signal occurs in any situation that doesn't directly involve fitness. And this certainly isn't true of words or signs. They can refer to anything at all, whether it has any connection with fitness or none. And, leaving aside one or two exceptions like "Fire!" or "Help!," a word can't, in itself, by itself, contribute in any way to fitness. And these exceptions, when you come to think about them, are more like ACS calls than regular words — they're tied to situations in just the way ACS signals are. If you doubt me, try shouting "Fire!" in a crowded theater, or ask yourself whether "fire" works the same way in "Help! Fire!" as it does in "There's nothing like a nice warm fire on a winter's evening."
(Continues…)
Excerpted from "Adam's Tongue"
by .
Copyright © 2009 Derek Bickerton.
Excerpted by permission of Farrar, Straus and Giroux.
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