Harnessed: How Language and Music Mimicked Nature and Transformed Ape to Man (9 page)

where the interaction can be either a hit or a slide. If we let
c
stand for a hit or a slide (because “c” can be pronounced either as a plosive, “k,” or as a fricative, “s”), and
a
stand for a ring (which, recall, can sometimes be wiggly), then the fundamental structure of solid-object physical events is exemplified by
caca
. Not
acac
. Not
cccaccca
. Not
accacc
. And so on. Letting
b
stand for hits and
s
for slides, events take forms such as
ba
,
sa
,
baba
,
saba
,
basaba
, and so on. Not
ab
or
sba
or
a
or
bbb
or
ssb
or
assb
or the like. This interaction-ring combination is perhaps
the
most fundamental event regularity in nature, and is perhaps the most perceptually salient. Objects percussively interact via either a hit or slide, and give off a ring. Our auditory system—and probably that of most other mammals—is designed to expect nature’s phonemes to come in this interaction-ring form.

Given the fundamental status of interaction-ring combinations, if language harnesses the innate powers of our auditory system, then we expect language to be built out of vocalizations that sound like interaction-ring. Do languages have this feature? That is, do plosives and fricatives tend to be followed by sonorants? Yes. A plosive or fricative followed by a sonorant is, in fact, the most basic and most common phoneme combination across languages. It is the quintessential example of a
syllable
. Words across humankind tend to look approximately like
ca
, or
caca
, or
cacaca
, where
c
stands for a plosive or fricative, and
a
for one or more consecutive sonorants. All languages have syllables of this
ca
form. And many languages—such as Japanese—
only
allow syllables of this form.

Whereas interaction-ring is the most fundamental natural combination of event atoms, ring-interaction is a combination that is
not
possible. A ring followed by an interaction sounds out of this world, as in my friend’s son’s Rubik’s Cube video. We therefore expect that languages tend to avoid combinations like
ac
and
acac
. This is, in fact, the case. The rarest syllable type is of this
ac
form, and words starting with a sonorant and followed by a plosive or fricative are rare. In data I collected at RPI in 2008 with the help of undergraduate student Elizabeth Counterman and graduate student Kyle McDonald, about 80 percent of our sampled words (with three or fewer non-sonorants) across 18 widely varying languages begin with a plosive or a fricative. (See the legend of Figure 9 for a list of the sampled languages.) And a large proportion of the words starting with a sonorant start with a nasal, like “m” and “n,” the least sonorant-like of the sonorant consonants (nasals at word starts can have a fairly sudden start, and are more plosive-like than other sonorant consonants).

Note that a word starting with a vowel does
not
start with a sonorant, because when one speaks such a word, the utterance actually begins with something called a
glottal
plosive
, produced via the sudden hitlike release of air at one’s voice box. To illustrate the glottal plosive, slowly say “packet,” and then slowly say “pack it.” When you say the latter, there can often be a sharp beginning to the “it,” something that will never occur before the “et” sound in “packet.” That sharp beginning is
the glottal plosive. Words starting with sonorants are, thus, less common than one might at first suspect. Even words like “ear,” “I,” “owe,” and “owl,” then, are cases of plosives followed by sonorants, and agree with the common hit-ring (the most common kind of interaction-ring) structure of nature.

Words truly beginning with a sonorant sound begin not with a vowel, but with a sonorant consonant like w, y, l, r, and m. When one says, “what,” “yup,” “lid,” “rip,” and “map,” the start of the word is nonsudden (or less sudden than a plosive), ramping up more gradually to the sonorant sound instead. And notice that words such as these—with a sonorant at the start and a plosive at the end—
do
sound like backwards sounds. Try saying the following meaningless sentence: “Rout yab rallod.” Now say this one: “Cort kabe pullod.” Although they are similar, the first of these meaningless sentences sounds more like events in reverse. This is because it has words of the ring-hit form, the signature sound of a world in reverse. The second sentence, while equally meaningless, sounds like typical speech (and event) sounds, because it starts with plosives.

Language’s most universal structure above the level of phonemes—the syllable—has its foundation, then, in physics. The interaction-rings of physical events got instilled into our auditory systems over hundreds of millions of years of vertebrate and mammalian evolution, and culture shaped language to sound like physics in order to best harness our hardware.

Before we move next to the shape of words, there is another place where syllables play a central role: in rhyme. Two words rhyme if their final syllables have the same sonorant sound,
and
the same plosive or fricative following the sonorant—for example, “snug as a bug in a rug.” The sonorant sound is the more important of the two: “bug” rhymes better with “bud” than with “bag.” Our ecological understanding of syllables may help to make sense of the perceptual salience of rhyme. When two events share the same ring sound, it means the same kind of object is involved in both events. For example, “tell and “sell” rhyme, and in terms of nature’s physics, they sound like two distinct events involving the same object. “Tell” might suggest that some object has been hit, and “sell” that that same object is now sliding. The “ell” in each case signals that it is the same object undergoing different events. This is just the kind of gestalt perceptual mechanism humans are well known to possess: we attempt to group stimuli into meaningful units. In vision this can lead to contours at distant corners of an image being perceptually treated as parts of one and the same object, and in audition it can lead to sounds separated by time as nevertheless grouped into the same object.
That’s
what happens in rhyme: the second word of a rhyming pair may occur several lines later, but our brain hears the similar ringing sound and groups it with the earlier one, because it would be likely in nature that such sounds were made by one and the same object.

In the Beginning

The Big Bang is the ultimate event, and even
it
illustrates the typical physical structure of events: it started with a sudden explosion, one whose ringing is still “heard” today as the background microwave radiation permeating all space. Slides didn’t make an appearance in our universe until long after the Bang. As we will see in this section, hits, slides, and rings tend to inhabit different parts of events, with hits and rings—bangs—favoring the early parts.

To get a feeling for where hits, slides, and rings occur in events, let’s take a look at a simpler event than the one that created the universe. Take a pen and throw it onto a table. What happened? The first thing that happened is that the pen hit the table; the audible event starts with a hit. Might this be a general feature of solid-object physical events? There are fundamental reasons for thinking so, something we discussed in the earlier section, “Nature’s Other Phoneme.” We concluded that whereas hits can occur without a preceding slide, slides do
not
tend to occur without a preceding hit. Another reason why slides do not tend to start events is that friction turns kinetic energy into heat, decreasing the chance for the slide to initiate much of an event at all. So, while hits can happen at any part of an event, they are most likely to occur at the start. And while slides can also happen anywhere in an event, they are less likely to occur near the start. Note that I am not concluding that slides are more common than hits at the nonstarts. Hits are more common than slides, no matter where one looks within solid-object physical events. I’m only saying that hits are more common at event starts than they are at nonstarts, and that slides are
less
common at event starts than they are at nonstarts.

Is this regularity about the kinds of interaction at the starts and nonstarts of events found in spoken language? Yes. Words of the form
bas
are more common than words of the form
sab
(where, as earlier,
b
stands for a plosive,
s
for a fricative, and
a
for any number of consecutive sonorants). Figure 9 shows the probability that a non-sonorant is a plosive (rather than a fricative) as one moves from the start of a word to non-sonorants further into the word. The data come from 18 widely varying languages, listed in the legend. One can see that the probability that the non-sonorant phoneme is a plosive begins high at the start of words, after which it falls, matching the pattern expected from physics. And, as anticipated, one can also see that the probability of plosives after the start is still higher than the probability of a fricative.

Figure 9
. This shows how plosives are more probable at the start of words, and fall in probability after the start. The y-axis shows the plosive-to-fricative ratio, and the x-axis the i
th
non-sonorant in a word. The dotted line is for words with two non-sonorants, and the solid line for words with three non-sonorants. The main points are
(i)
that plosives are always more probable than fricatives, as seen here because the plosive-to-fricative probability ratios are always greater than 1, and
(ii)
that the ratio falls after the start of the word, meaning fricatives are disproportionately rare at word starts. These data come from common words (typically about a thousand) from each of the following languages: Japanese, Zulu, Malagasy, Somali, Fijian, Lango, Inuktitut, Bosnian, Spanish, Turkish, English, German, Bengali, Yucatec, Wolof, Tamil, Taino, Haya.

We just concluded that hits are disproportionately common at the starts of events in nature, and that this feature is also found in language. But we ignored rings. Where in events do rings tend to reside? In the previous section (“Nature’s Syllables”) we discussed the fact that rings do not start events, a phenomenon also reflected in language. How about after the start of a word? There would appear to be a simple answer: rings always occur after physical interactions, and so rings should appear at
all
spots within events, following each hit or slide.

But as we will see next, reality is more subtle.

The First Was a Doozy

While it is true that all physical interactions cause ringing, the ringing need not be audible, a point that already came up in the section called “Two-Hit Wonder.” In this light, we need to ask,
where in events are the rings most audible
? Consider the generic pen-on-table event again. The beginning of that event—the audible portion of it, starting when the pen hit the table—is where the greatest energy tends to be, and the ring sound after the first hit will therefore tend to be the loudest. If the pen bounces and hits the table again, the ring sound will be significantly lower in magnitude, and it will be lower still for any further bounces. Because energy tends to get dissipated during the course of an event, rings have a tendency to be louder earlier in the event than later in the event. This is a tendency, but it is not always the case. If energy gets added during the event, ring magnitude can increase. For example, if your pen bounces a couple of times on the table, but then bounces
off
the table onto the floor, then the floor hit may well be louder than the first table hit (gravity is the energy-adding culprit). Nevertheless, in the generic or typical case, energy will dissipate over the course of a physical event, and thus ringing magnitude will tend to be reduced as an event unfolds. Therefore, the audibility of a ring tends to be higher near the start of an event; or, correspondingly, the probability is higher later in an event that a ring might
not
be audible.

If language is instilled with physics, we would accordingly expect that sonorant phonemes are more likely to follow a plosive or fricative near the start of a word, and are more likely to go missing near the end of a word. This is, in fact, the case. Figure 10 shows how the probability of a sonorant following a non-sonorant falls as one moves further into a word, using the same data set mentioned earlier. For example, words like “pact” are not uncommon in English, but words like “ctap” do not exist, and are rare in languages generally.

Figure 10
. This shows that sonorant phonemes are more probable near the starts of words, namely just after the first non-sonorant (usually a plosive). The square data are for words having two non-sonorants, and the triangle data for words having three non-sonorants.

We have begun to get a grip on how hits, slides, and rings occur within events, but we have only considered their probability as a function of how far into the event they occur. In real events there will be complex dependencies, so that if, say, a slide occurs, it changes the probability of another slide occurring next. In the next section we’ll ask, more generally, which combinations of hits and slides are common and which are rare, and then check for the same patterns in language.

Nature’s Words