Excerpts – part 1

KANZI IS ONE REMARKABLE APE—BONOBO, TO BE precise. He was adopted—kidnapped actually—by the dominant female, named Matata, of a captive colony at the Yerkes Primate Center in Georgia, who, as it happened, was being taught to communicate with humans through lexigraphs, graphic symbols of single words. Matata was not a great student, a bit too old for that sort of thing, but Kanzi proved extraordinarily apt. He had been just sort of hanging around during Matata’s sessions, not paying much attention, seemingly. It soon became obvious, though, that he had observed and learned much, out of the corner of his eye, as it were. When his training became more explicit, he soon learned the meaning of well over 300 symbols, by means of which he could express his desires to his human companions. He also understood spoken English—thousands of words, in fact—which he could translate into lexigraphic symbols by pressing the images on a screen. Even more impressive, Kanzi could communicate verbally, in his normal Chimpansese, with his late stepsister, Panbanisha, over the phone. They had been known to gossip.

There are actually two species of chimpanzees. The one usually displayed in zoos—Pan troglodytes—is by far the most common and the one for which the term “chimpanzee” is usually reserved. Kanzi belongs to the other, far less common species (Pan paniscus), called bonobos, which have a restricted range in the Congo forests. Bonobos were formerly called “pygmy chimpanzees,” though they are no shorter than common chimpanzees. (The name may derive from the fact that they share their forest habitat with small-statured humans formerly known as “pygmies.”) Bonobos are significantly leaner than chimpanzees and have longer legs; their necks are thinner, their shoulders more narrow, and their chests less deep. Bonobos are altogether less robust than chimpanzees, less physically imposing. The bonobo head is also significantly smaller than that of the chimpanzee, with a less protruding snout and smaller brow ridges. On top of the head is a distinctive mop of long hair that tends to form a natural part down the middle.

But it is the behavioral differences between chimpanzees and bonobos that have received the most attention of late. These behavioral differences are much more pronounced than the physical differences and have engendered much discussion for their implications regarding human evolution.

Before bonobos took center stage, chimpanzees were thought to be the best models for extrapolating human behavioral evolution, especially once it was discovered that chimpanzees routinely hunt other primates in an organized and premeditated manner. This finding fit in nicely with a man-the-hunter narrative and certain sociobiological elaborations of its implications, especially regarding putative sex differences in behavior. Also conforming nicely to this narrative is the fact that chimpanzee males are violent, not just individually but often in groups, raiding the territories of adjacent groups. These group conflicts can be quite grizzly and have been touted as the wellspring of human warfare.

Enter the bonobo, the hippy ape. Actually, bonobos embrace the hippy ideal far more than any human hippies ever did, for bonobos are not only pacifist; they also engage in more sex than the most nymphomaniac members of our own species. Rarely do a couple of hours pass without at least some serious foreplay. This rampant sex is also quite promiscuous—partners are ever changing—and indiscriminate with respect to gender. Bonobo lesbian sex is especially rife, and many believe it is the behavior around which bonobo society is organized. For bonobos, in stark contrast to the macho patriarchal chimpanzees, live in a female-dominated society. Male bonobos, like Kanzi, are larger and stronger than female bonobos, but not as much larger and stronger as are male chimpanzees in relation to female chimpanzees. Put another way, bonobos are less sexually dimorphic than chimpanzees. Moreover, whatever size advantage a male bonobo enjoys is outweighed by genitally cemented female bonobo solidarity.

Inspired by the farm fox experiments, Brian Hare and coworkers proposed an overarching explanation for the physical and behavioral differences of chimpanzees and bonobos: that bonobos are, in essence, self-domesticated. They hypothesize that bonobos have experienced natural selection for tameness, from a more chimp-like starting point. Hare equates tameness with lower levels of aggression, but, as we saw with the fox domestication project, a reduction in fear is at least as important an element in tameness as lowered aggression is. Indeed, lowered aggression may be largely a by-product of the nonaggressive.

Richard Francis’s book, Domesticated, is not simply about domestication. It’s a cross disciplinary look at human evolution, biology, culture, psychology and sociology. Over the next few months I’ll be featuring a few tantalizing extended excerpts from this engaging book.

Domesticated: Evolution in a Man-Made World, Richard C. Francis, W. W. Norton, 2015

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Squeaky Floorboard

There’s occasional talk about an audio system’s noise floor. You may hear someone claim a new component, or set of wires, or whatever, has lowered their noise floor to provide a “darker background,” or an “inky blackness.”


No doubt, noise is distortion. No doubt, I’m a freak about distortion. No doubt, a lower noise floor is better. No doubt, the noise floor on my system is not so low. No doubt, as high as it is, no one who has listened, and listened critically, to my system has ever mentioned the noise level, or even noticed it. And yet, I can lower the noise floor easily.

Let’s back up. There are two noise floors to consider. First is the electrical noise floor that makes its way through to the speakers. In most cases, what you’ll hear through a speaker is nada. However, my system, and plenty of others, are noisy enough to hear. If you get close to the tweeter, you’ll hear a little hiss. As you back away from the speaker the slight hiss quickly disappears. At the listening position it’s meaningless simply because of the other noise floor. So, reducing the electrical noise to “inky blackness” is nice, but inconsequential, and as we shall see, inaudible at your listening position.


The second noise floor is your room. Generally it’s much higher than you might suspect. Most rooms have a noise floor that’s easily 35-40 dB. My dedicated listening room is about 31.5 dB (29 dB A weighted). That low number is because it’s in the basement and insulated with rock wool. But that number could be reduced by 1.5 dB. That may not sound like much until you realize all the reduction is above 200 Hz, and clearly audible throughout the room. The extra noise is from the amps’ fans. They could be disconnected to effectively and audibly lower the room’s noise floor. Does it bother me? Sometimes. When there’s a soft-soft passage, at the end of a fade-out, between cuts, I hear it. It doesn’t belong there, and I’d rather not hear it. Why haven’t I disconnected the fans? The amps also have a number of lights, bright flashing lights. The room is used also for movies, and the amps are up front. Those lights are distracting, so the amps have been covered. The cover, though, partially restricts airflow for cooling. Natural convection would be okay if it weren’t for the cover, so the fans are left running. The cover is 6mm industrial felt, which is heavy enough to absorb some of the fan noise. Without the felt, noise reaches 33 dB (another 1.5 dB), and the peak frequency is close to 1 kHz. That frequency is very audible. Fortunately, the peak is well absorbed by the felt.


Still, this raises a question. If the room’s noise floor, under really good conditions, is around 30 dB, what’s the point of reducing the system’s electrical noise floor when it isn’t even audible more than a few centimeters from the speakers?

Let’s get real. The “inky blackness,” that “darker background,” is so far below your ambient noise level, you couldn’t hear the difference if it went up or down by an order of magnitude. No power cord, no interconnect, no speaker wire, no power conditioner is going to have any meaningful effect, no matter how much you pay, or how much the manufacturer promises. The benefit is nada. Fix the squeaky floorboard. That you’ll hear.

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