Just as we find cats with lifestyles they are not meant to have, we humans are apes living an un-ape life. Far beyond being potty trained, we build the very toilets we sit on. In light of tuna fish and kitty litter, in this book we have examined whether simulacra of nature could be the key to our humanity. Rather than supposing that our wild bits have evolved and changed to help us become modern humans, and rather than supposing the opposite—that our feral brain is a general-purpose learning machine that is extensively wired during our lifetime to make us genteel—in this book we have examined a third possibility: that our brains, to this day, are just as they were before anyone spoke or folded napkins, and that culture evolved to harness our ape powers, cleverly turning them into a new kind of power. Apes became literate and musical not because language and music got themselves innately encoded into the brain, but because the brain got its signature stamped upon language and music. We’re cats, not dogs.
In particular, this book has been about culture’s general strategy for harnessing us. The trick is to structure modern human tasks as tasks at which our ape selves already excel. And one surefire way to do this is to make the task thoroughly “like nature.” This book set out to put flesh on the bones of this idea, and to convey preliminary evidence that this is the strategy culture used to make us fit into modernity: making modernity fit us.
(a) Speech sounds like solid-object physical events, (b) music sounds like people moving, and (c) Homo sapiens became modern humans by virtue of cultural evolution designing language and music to mimic nature—by virtue of nature-harnessing. That’s the book in a nutshell. We have been down and dirty discussing (a) and (b) over the last three chapters, and these, in conjunction with arguments in The Vision Revolution that writing looks like opaque objects strewn in 3-D space, are the principal arguments for (c), that nature-harnessing is the mechanism for how we got from ape to man. Speech and music are the most central and transformative—revolutionary—powers we possess, and that’s why it is reasonable to say that nature-harnessing is the mechanism that created humans.
And if nature-harnessing is what made us, and if other animals don’t get made in this way, then it is worth reflecting upon what we humans are. How can we think about ourselves? To help illustrate what we are, it helps to back up really far away. So let’s consider how aliens try to make sense of us . . .
When aliens come to Earth to investigate life here, they don’t simply beam up a specimen and start probing. (And they’re also, by the way, not disproportionately interested in the anus.) Only a novice prober would do a simple beam-and-probe, and would surely get a quick rap on the proboscis from the instructor. The problem with abducting an animal of interest, all by itself, is that you can’t understand an animal without an appreciation of the environment the animal inhabits.
What an experienced alien prober does is gather as much information about the animal’s habitat as possible. In fact, the aliens beam up entire habitats so that they can study the animal in its home at their leisure. Alien Probe School graduates are consummate ecologists, understanding that organisms evolved to do stuff with their complex mechanisms, but that if you drop an organism into an environment for which it did not evolve, it will often do other stuff, and usually quite unsophisticated stuff.
By following their alien principles of good probing, they’ll have abducted what they need in order to someday, and with great effort, have a thorough knowledge of the organism, from its genome to its “phenome.” The phenome is the set of things the animal can do, implemented ultimately by the genome and the way it acts within the evolutionary habitat. For example, your cell phone’s genome is its electronic circuitry (or perhaps the engineer’s drawings for the circuitry), whereas its phenome is the list of things it can do, often enumerated in the user’s manual—exactly the manual that is missing for the Earth organisms the alien probers want to unravel.
But something unexpected happened when they applied these wise principles to humans, abducting an entire primitive tribe and the mountain they lived on. They already had abducted earlier hominids who had no language or music, and were interested to see what was new about these speaking and singing humans. To their surprise, the aliens could discern no difference between the nonspeaking, nonmusical hominids and the speaking and singing humans. Their biology was indistinguishable, they concluded. They were the same animal. Could the difference be due to a difference in habitat? No, they concluded, the earlier and newly abducted mountains appear to have no relevant differences. Same animal, same habitat, and yet the modern humans are a giant leap beyond, or at least distinct from, the more ancient Homo sapiens.
They scratched their antennae. Why, the aliens wondered, did the modern humans behave so fundamentally differently? Why did they have language and music? Why did the modern humans seem like something fundamentally different from the great apes, whereas the nonlinguistic, nonmusical humans seemed to fit more within the apes, albeit as a very bright great ape? How could two identical creatures in identical habitats end up so different in sophistication that it seemed natural to deem them different species?
The modern humans clearly must have learned language and music. But that only created another dilemma for the probers. How can you teach an animal a lesson so powerful that it practically becomes another species? Speech and music comprehension, the aliens knew, are astoundingly complex, with just the kind of complexity natural selection creates. These modern humans, the aliens noted, were competent at language and music in the highly adapted way animals evolve to be good at things. But from their alien experiences as ecologists, they knew that if an animal is not designed to accommodate that level and type of complex processing, then you can’t just force-feed it the learning. You can’t teach a deer to catch and eat mice. No training course will get your dog to climb trees like a monkey. And you can’t train a human to comprehend fax machine sounds. You simply cannot teach old hominids new tricks worthy of natural selection. The human brain is not such a rich general-purpose learning apparatus that it can master tasks as richly complex as language and music. Yet there they were, modern humans with brains highly honed for speech and music. The alien probers were stumped.
They reasoned that humans don’t have language or music innately installed in their heads. And neither one comes from their natural habitat. And they also can’t simply learn something that complicated. There must be selection of some kind underlying the human capability to do language and music, but what kind of selection could it be, if it is neither natural selection nor learning?
One of the alien probers wondered whether there might be design, or selection, underlying the difference between modern humans and their nonlinguistic and nonmusical ancestors—not natural selection, but cultural selection. This is a selection process that selects not on biology, but on human artifacts that are used by biology. The human artifacts are animal-like in the sense that they themselves have evolved over time, under selection pressure. These artifact-creatures (in the realm of “memes”), like naturally selected biological creatures, can be highly complex and intricately adapted, with all the hallmarks of an engineering masterpiece.
“Aha!” the alien prober exclaimed. The modern humans are not merely learning language and music, they’re being raised in an environment with symbionts. Language and music are technological masterpieces that evolved to live with nonlinguistic hominids and transform them into something beyond their biology. What makes these modern humans no longer the nonlinguistic Homo sapiens apes they biologically are is not on the inside, and not in the ancestral natural environment. Language and music are evolved, organism-like artifacts that are symbiotic with these human apes. And like any symbiont, these artifact symbionts have evolved to possess shapes that fit the partner biology—our brains.
What are we, then, in the eyes of alien probers? We are our biology, from the genes on up. But we are more than that, as indicated by the fact that the probers don’t abduct just a human, but, rather, abduct entire human hab
itats. We are our biology within its appropriate habitat. But that’s true of all animals on Earth. The special thing the aliens had to grapple with when they started probing humans was that biology and habitat are not enough. They needed to abduct the cultural-artifact symbionts that were coevolving with us. That’s not something any other animal can lay claim to. The pieces of what we are can be found in our wet biology, and in the habitat, but also in the artifactual symbionts we have been coevolving with. Our language, music, and other highly culturally evolved technologies are, like our genes and our habitat, deeply part of the modern human recipe. The human code is not just the genome, and not just the genome plus the habitat. The human code is now partly found in the structures of language and other cultural artifacts.
Through this allegory of alien probers, we can better see what we are. We owe our modern human identity to cultural symbionts that have evolved to get into our brains and harness us into something new. Cultural “animals” evolving to be symbiotic with humans: that is something the aliens could wrap their proboscises around, for they knew of lots of symbiotic interactions around the galaxy.
Although the aliens concluded that these cultural symbionts must have culturally evolved to fit the human brain, they hadn’t figured out how the symbionts got into human heads. “How did the cultural symbionts get in?” they wondered. And the answer they discovered: “Ah! They got in by mimicking nature.”
Encore
Although Chapter 4 presented a variety of evidence that the structure of music has the signature of human movers, there is additional evidence that couldn’t reasonably be fit into that chapter, and so it appears here in the Encore.
1 The Long and Short of Hit
The mysterious approaching monster from the section titled “Backbone” in Chapter 4 was mysterious because you mistakenly perceived a hit sound rapidly following the footstep; that is, you perceived the between-the-steps interval to be split into a short interval (from step to rapidly following hit) and a long interval (from that quick post-step hit to the next footstep). The true gait of the approaching lilting lady had its between-the-steps interval broken, instead, into a long interval followed by a short interval. My attribution of mystery to the “short-long” gait, not the “long-short,” was not arbitrary. “Short-long” is a strange human gait pattern, whereas “long-short” is commonplace.
Your legs are a pair of 25-pound pendulums that swing forward as you move, and are the principal sources of your between-the-steps hit sounds. A close look at how your legs move when walking (see Figure 41) will reveal why between-the-step hits are more likely to occur just before a footstep than just after. Get up and take a few steps. Now try it in slow motion. Let your leading foot hit the ground in front of you for its step. Stop there for a moment. This is the start of a step-to-step interval, the end of which will occur when your now-trailing foot makes its step out in front of you. Before continuing your stride, ask yourself what your trailing foot is doing. It isn’t doing anything. It is on the ground. That is, at the start of a step-to-step interval, both your feet are planted on the ground. Very slowly continue your walk, and pay attention to your trailing foot. As you move forward, notice that your trailing foot stays planted on the ground for a while before it eventually lifts up. In fact, your trailing foot is still touching the ground for about the first 30 percent of a step-to-step interval. And when it finally does leave the ground, it initially has a very low speed, because it is only just beginning to accelerate. Therefore, for about the first third of a step, your trailing foot is either not moving or moving so slowly that any hit it does take part in will not be audible. Between-the-footsteps hit sounds are thus relatively rare immediately after a step. After this slow-moving trailing-foot period, your foot accelerates to more than twice your body speed (because it must catch up and pass your body). It is during this central portion of a step cycle that your swinging leg has the energy to really bang into something. In the final stage of the step cycle, your forward-swinging leg is decelerating, but it still possesses considerable speed, and thus is capable of an audible hit.
Figure 41. Human gait. Notice that once the black foot touches the ground (on the left in this figure), it is not until the next manikin that the trailing (white) foot lifts. And notice how even by the middle figure, the trailing foot has just begun to move. During the right half of the depicted time period, the white leg is moving quickly, ready for an energetic between-the-steps hit on something.
We see, then, that there is a fundamental temporal asymmetry to the human step cycle. Between-the-steps hits by our forward-swinging leg are most probable at the middle of the step cycle, but there is a bias toward times nearer to the later stages of the cycle. In Figure 41, this asymmetry can be seen by observing how the distance between the feet changes from one little human figure to the next. From the first to the second figure there is no change in the distance between the feet. But for the final pair, the distance between the feet changes considerably. For human gait, then, we expect between-the-steps gangly hits as shown in Figure 42a: more common in mid-step than the early or late stages, and more common in the late than the early stage.
Figure 42. (a) Because of the nature of human gait, our forward-swinging leg is most likely to create an audible between-the-steps bang near the middle of the gait cycle, but with a bias toward the late portions of the gait cycle, as illustrated qualitatively in the plot. (b) The relative commonness of between-the-beat notes occurring in the first half (“early”), middle, or second half (“late”) portions of a beat cycle. One can see the qualitative similarity between the two plots.
Does music show the same timing of when between-the-beat notes occur? In particular, are between-the-beat notes most likely to occur at about the temporal center of the interval, with notes occurring relatively rarely at the starts and ends of the beat cycle? And, additionally, do we find the asymmetry that off-beat notes are more likely to occur late than early (i.e., are long-shorts more common than short-longs)? This is, indeed, a common tendency in music. One can see this in the classical themes as well, where I measured intervals from the first 550 themes in Barlow and Morgenstern’s dictionary, using only themes in 4/4 time. There were 1078 cases where the beat interval had a single note directly in the center, far more than the number of beat intervals where only the first or second half had a note in it. And the gaitlike asymmetry was also found: there were 33 cases of “short-longs” (beat intervals having an off-beat note in the first half of the interval but not the second half, such as a sixteenth note followed by a dotted eighth note), and 131 cases of “long-shorts” (beat intervals having a note in the second half of the interval but not the first half, like a dotted eighth note followed by a sixteenth note). That is, beat intervals were four times more likely to be long-short than short-long, but both were rare compared to the cases where the beat interval was evenly divided. Figure 42b shows these data.
Long-shorts are more common in music because they perceptually feel more natural for movement—because they are more natural for movement. And, more generally, the time between beats in music seems to get filled in a manner similar to the way ganglies fill the time between steps. In the Chapter 4 section titled “The Length of Your Gangly,” we saw that beat intervals are filled with a human-gait-like number of notes, and now we see that those between-the-beat notes are positioned inside the beat in a human-gait-like fashion.
Thus far in our discussion of rhythm and beat, we have concentrated on the temporal pattern of notes. But notes also vary in their emphasis. As we mentioned earlier, on-beat notes typically have greater emphasis than between-the-beat notes, consistent with human movers typically having footsteps more energetic than their other gangly bangs. But even notes on the beat vary in their emphasis, and we take this up next.
2 Measure of What?
Thus far we have discussed beats as footsteps, and between-the-beat notes as between-the-footsteps banging ganglies. But there are other rhythmic features of music that oc
cur at the scale of multiple beats. In particular, music rarely treats each and every beat as equal. Some beats are special. In ¾ time, for example, every third beat gets a little emphasis, and in 4/4 time every fourth beat gets an emphasis. This is the source of the measure in music, where the first beat in each measure gets the greatest emphasis. (And there are additional patterns: in 4/4 time, for instance, the third beat gets a little extra oomph, too, roughly half that of the first.) If you keep the notes of a piece of music the same, but modify which beats are emphasized, the song can often sound nearly unrecognizable. For example, here is “Twinkle, Twinkle Little Star,” but with some unusual syllables emphasized to help you sing it in ¾ time rather than the appropriate 4/4 time. “TWI-nkle, twi-NKLE, lit-tle STAR,
Why should a difference in the pattern of emphasis on beats make such a huge difference in the way music sounds to us? With the movement theory of music in hand, the question becomes: does a difference in the pattern of emphasis of a mover’s footsteps make a big difference in the meaning of the underlying behavior? For example, is a mover with a ¾ time gait signature probably doing a different behavior than a mover with a 4/4 time gait signature?
Harnessed: How Language and Music Mimicked Nature and Transformed Ape to Man Page 20
