Social interaction brings with it enormous potential for changing the way individual members of a group go about their day-today survival. Though basic subsistence is always challenging, life in complex societies such as those constructed by many primates is demanding in a very different way. There are clear benefits to be had for those members of the group who can manipulate the social structure of the clan by outmaneuvering their peers. Individuals must be adroit at reading the social cues of the group; predicting the consequences of their own behavior and that of others; and tallying the complicated balance sheet of advantages and losses that revolve around these myriad social transactions. Hence, social primates are required to be calculating beings by the very nature of the system they create and maintain. In such a system, social skill, communication, and intellect are inseparable.
The selection pressures that led to early hominids’ growing need for more sophisticated subsistence technology contributed to two important changes in their social behavior: (1) they granted offspring a longer grace period of dependence on adults, free to learn about their habitat through play, exploration, and experimentation; and (2) they encouraged greater interaction across generations whereby the young learn about subsistence technologies from elder, more experienced teachers. These shifts markedly widened the age range of the communal setting, and brought the very young into contact with the very old, resulting in particularly difficult social challenges. Both the older and the younger members of a community tend to be most dependent on the core adults of the group; thus an evolutionary mechanism must exist to facilitate or encourage the adults to cater to the whims, desires, and needs of these two groups. There must be some adaptive benefit for the adults that outweighs the cost to them in caring for the young, old, sick, and infirm. That adaptive benefit, of course, is mediated by the pleasure derived from social bonding—the pleasure I found in the exchange with my niece.
Many scholars agree that two behaviors probably provided the survival edge that benefited
Homo sapiens
over their contemporaries: the evolution of social attachment and language. I believe that both social attachment and language evolved from selection factors I call proto-emotions. These are basic, instinctual emotions that are exhibited by many primates: pleasure, fear, anger, disgust, sadness, surprise, and the various hungers. Proto-emotions have a very quick onset and are short-lived, almost like a reflex. The social emotions—for instance, happiness, maternal love, sexual love, infatuation, pride, and admiration—differ from proto-emotions in that they consist of long-lasting behavioral and mood states that typically outlast precipitating conditions and increasingly depend on a capacity for self-reference and reflection. These are the modern emotions we experience today that evolved from conditions in our ancestral past, remnants of a prior age where life was lived as hunter-gatherers on the open plains of the savanna. In the pages that follow, we’ll explore how pleasure led to the evolution of social attachment and language, and most importantly, how it shaped the positive social emotions that reverberate through our lives so profoundly today. Why did our instinct for pleasure drive us to become such loquacious, social creatures? And how did this newfound love of gabbing, gossip, and group affiliation result in modern emotions such as love, lust, happiness, and joy?
The Language Link
We take for granted that language can illuminate what is subjective, the amorphous yet innumerable feelings, thoughts, and inklings that mix through our minds like hot and cold currents every moment of the day. We like to think that other humans share this dizzying internal menagerie, or at least some parts of it. But what would a dog say if it could speak a human language? Would a dog’s inner emotional experiences be close enough to a human’s so that a common lexicon might emerge? Could we really learn more about the thoughts and feelings of animals—what is in their hearts and minds—if we could decode their vocalizations?
The linguistic philosopher Ludwig Wittgenstein argued that all truths, be they emotional, moral, aesthetic, or intellectual, are known only through experience. He suggested that they lose their real value and meaning in the telling, and that language is merely a form of depiction, a representational system that inevitably fails to characterize our genuine nature since it can only work through analogy. Thus, even if we successfully decode an animal’s sounds, we could not truly understand them because language is but a mirror of reality rather than the genuine object, and an animal’s reality, as the argument goes, is too far removed from our own. Language is the finger pointing at the moon, not the moon itself. In cognitive science circles, this is known as the representation problem—deciphering how symbols, such as language, map onto subjective experiences, such as feelings and thoughts. The representation problem, of course, extends to all symbol-using species, and we will revisit it throughout this book.
A kissing cousin to this line of argument is the classic linguistic problem of induction—how one infers the referent of a word from a speaker’s vocalizations and behavior. Imagine you are a linguist encountering a newly discovered human population. One of the clan members shouts “agovi” as a turtle saunters by.Your first guess, probably, is that
agovi
means “turtle.” This is a perfectly reasonable inference, since at least in English, comments elicited by an object typically refer to the object itself. But this is premature because agovi may also refer to animals or objects that move slowly, have shells, are hard and spherically shaped, are smaller than a house but larger than a breadbox, or are the most important ingredient for soup.The induction problem shows that any attempt to determine word meaning strictly from behavior is in deep trouble, since there are simply too many possible interpretations for any specific action. How did the first language emerge, then, if we can’t even get past single words? I believe a reasonable alternative is that hominids’ initial foray into semantics, and perhaps the genesis of structured language, were driven not by their desire to label everything in sight, but rather by their common need to exchange emotional information.
How did proto-emotions, particularly pleasure, foster the evolution of modern language? There are many theories that are fun to consider. Did language develop in response to the increasingly complicated social lives our ancestors lived, or is it perhaps the other way around, a new tool that evolved for other reasons—a spandrel—that facilitated greater socialization? What did the first languages sound like and how did they facilitate social attachment and the development of modern emotions?
Although it’s impossible to jump in a time machine and listen in on a prehistoric town meeting, we can adopt a different strategy. We can look to a source of information that will help us decipher how the pleasure instinct may have shaped social attachment and linguistic life for hominids—the emergence of spoken language in children. This is not an attempt to resuscitate the old Haekelian idea that ontogeny (the development of an individual) recapitulates phylogeny (the development of a species).This notion is based on the assumption that the ontogenetic form being considered develops through a series of stages that are essentially re-creations of the adult forms of its evolutionary predecessors.We will employ a more modern view that has emerged recently, which instead emphasizes studying the embryological and developmental commonalities and differences among genetically similar species. This theoretical approach never arose in Haekel’s day because it depends on the modern science of genetics. We will use it here because learning how an infant becomes linguistic can tell us a great deal about how language arose in our species as an important tool for emotional expression. “The human race began to talk as babies begin to talk,” noted the psychologist Carl Johnston, “. . . in the prattle of every baby, we have a repetition in a minor key of the voice of the earliest man . . . by watching the first movements of speech in a baby, we see once more the first steps in articulate language, which the whole world of man took in dim ages long ago.”
The Trouble with Tribbles
In ninth grade I remember reading a novel set in the distant future where a highly sophisticated artificial intelligence program is implanted into robots, eventually giving them enough brainpower to take over the world from humans, outthinking our every move. If you want a more probable scenario, one that at least makes sense from an evolutionary perspective, our mechanized subjugators are most likely to be adorably cute little creatures—perhaps puppylike—that gain power over us by tapping into our emotions rather than our rational components of mind. For primates, cuteness is more than simply a disarming factor. In our robots, cuteness would ensure that humans promote their survival by taking care of them, pampering them as one might an infant, working for the benefit of their continued comfort. In short, we would develop many of the behaviors and feelings toward them that go along with social attachment. The process is reminiscent of an old
Star Trek
episode in which the away team that has beamed down to the planet below encounters a species of hamsterlike critters known only as Tribbles. Going against Spock’s counsel, the team brings the harmless creatures on board the
Enterprise
, to the delight of the crew, who notice that when petted, Tribbles sing a beautiful cooing song. Before long, playing with Tribbles becomes the primary recreation of the shipmates, who are unable to resist their fuzzy appearance and soothing sounds. Meanwhile, the captain and Dr. McCoy begin to realize that petting Tribbles stimulates them to reproduce, and before long the
Enterprise
is in a desperate state, about to be overwhelmed by the exponential growth of these little fur balls. Soon Tribbles are everywhere, popping out of the food replicators, cooing from inside the ship’s main computer consoles; they have reached every nook and cranny of the vessel. Only Spock, devoid of emotions, seems immune to their charms and quickly takes control of the situation by isolating these dangerously lovable creatures from the rest of the crew.
The survival of all mammals, particularly the social primates, depends critically on their ability to secure attachment and nurturance from those around them. In most primates this dependence is aimed directly at the mother, who becomes involved in a complicated species-specific exchange with her offspring, employing whatever version of “motherese” phylogeny has given her. In humans and other mammals, the exchange between parent and offspring that leads to bonding and attachment can be likened to a conversation. Even though structured language may be entirely absent in the species, a turn-taking of sorts occurs, with certain physical and behavioral characteristics of the newborn eliciting a nurturing response from the parent, which then evokes yet more stimulation from the newborn, continuing the cycle. In humans this exchange is partly composed of prelinguistic vocalizations at first, with rapid phonological development that mirrors emotional expression in the first twenty-four months.
Infants enter the world displaying a clear preference for the language spoken by their mother. For instance, studies have demonstrated that French babies as young as four days old suck a nipple more diligently when hearing French than when hearing Russian or English. Likewise, Russian newborns prefer to hear Russian rather than French or English or Italian. Detailed experiments following up on these observations showed that babies tune into the prosody (timing, stress, and inflection) of speech patterns, since playing tapes of the languages backward—which preserves most of the vowels and consonants but alters the melody—eliminates the preference. Hence, newborns are predisposed to pay attention to prosodic features of their mother’s voice. Indeed, infants instinctually take such pleasure from these melodic elements of speech that they can be conditioned using prosody as a positive reinforcer (a reward) in the same way as can be done using other pleasurable experiences, such as access to its mother’s milk.
These findings are less surprising when we remember that prosody conveys the emotional tone of a message. “Communication is successful,” it is said, “not when hearers recognize the linguistic meaning of the utterances, but when they infer the speaker’s ‘meaning’ from them.” Many of the linguistic cues used to express intention are nonverbal. Systematic variation in pitch, tone, and duration of sounds—the music of language—is the primary venue for the infant, and it is in these signals that babies generally show the greatest interest. The newborn is naturally attracted to prosodic cues precisely because they contain the emotional meaning of speech, the very part of the message that is both critical to its social attachment with caregivers and accessible to its preverbal mind.
Interestingly, mothers across the globe—from culture to culture—speak practically identical versions of “motherese” to their infants: a complex blend of exaggerated tonal variation, eyes widened with expressive facial postures, and prodigious use of the high-toned “Hmm?” Wherever there are infants, we encounter baby talk, and it would be naive to consider this a form of linguistic instruction; the baby is certainly not enduring grammar drills. Rather, it is the innate social and emotional responsiveness of these inquisitive Lilliputian bundles that compels adults—mothers, fathers, brothers, sisters, and the rest—to speak motherese. The tiny linguophile naturally searches the faces and emotional expressions of nearby adults, an effort in identification and novelty-seeking that promotes further stimulation from parents.“The development of linguistic communication is a story about the preoccupation among the human young with things that move—faces that wrinkle, eyes that dance, voices that undulate, and hands that wiggle through the air,” wrote child psychologist John Locke.“Parents obviously understand this and, correctly believing that more is better, exaggerate their facial and vocal movements when addressing their young.And to good developmental effect, for the cues to phrase boundaries are prosodic, and the cues to vocal turn taking include variations in pitch and gaze.”