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Lux DIRECTOR, ANCILLARY PRODUCTS: Diane McGarvey PERMISSIONS MANAGER: Linda Hertz MANAGER OF CUSTOM PUBLISHING: Jeremy A. Abbate CHAIRMAN EMERITUS: John J. Hanley CHAIRMAN: Rolf Grisebach PRESIDENT AND CHIEF EXECUTIVE OFFICER: Gretchen G. Teichgraeber VICE PRESIDENT AND MANAGING DIRECTOR, INTERNATIONAL: Charles McCullagh VICE PRESIDENT: Frances Newburg ® Letters EDITORS@ SCIAM.COM “IN ‘EVALUATING THE THREAT’ [News Scan, December 2001], Ed Regis confuses the threat of biological weapons to public health with their threat to national security,” writes C. Allen Black of the University of Pittsburgh. “The fact that bioweapons are not likely to be used for mass destruction is of no comfort or even practical relevance when our government and the entire U.S. infrastructure is vulnerable to one or a few men that the police and government seem powerless to find or stop. Perhaps after the anthrax attack, there is no justification for mass vaccinations based on the public health threat. From now on, though, an oath of office should be preceded by vaccination.” Below, readers respond to this and other topics from the December 2001 issue. PRIVACY, ANONYMITY AND THE DIFFERENCE BETWEEN THEM “Here’s Looking at You” [SA Perspectives] described electronic surveillance in public places as a matter of privacy versus security. What is unsettling, though, is the loss not of privacy but of anonymity. No one who is in a public place or engaging in transactions or entry that requires identification has any expectation of privacy. Now, however, we are losing the illusion of anonymity. Welcome to the real world. What troubles me is the recording and storing of these identifications. I don’t mind if someone can identify me walking down the street, going to a ball game or entering a national park. I do mind if these events are recorded and filed with no restrictions on the duration of storage or accessed without just cause. Without such restrictions, this would indeed be an invasion of my privacy. CLAY W. CRITES West Chester, Pa. WHEN SAGE WASN’T When SAGE was first deployed in the early 1950s, I was a U.S. Air Force fighter pilot flying F-86D all-weather interceptors in the Air Defense Command [“The Origins of Personal Computing,” by M. Mitchell Waldrop]. Ours was one of the first squadrons to be equipped with Datalink, a feature that enabled SAGE to transmit steering commands directly to the autopilot in our aircraft. After getting airborne, establishing voice and data contact, and engaging the autopilot, the fighter pilot essentially became a passenger (a somewhat reluctant and skeptical passenger, I might add) in an aircraft being directed toward an intercept by SAGE. Sometimes the process worked reasonably well, but there were frequent problems, including sudden, unexpected and often violent episodes of pitching or rolling that required immediate disengagement of the autopilot to prevent losing control of the aircraft. As you might imagine, these incidents could be a bit startling, especially at night or in bad weather, and did little to increase my confidence in SAGE or the Datalink remote-control system. At the time, we usually attributed these problems to faulty equipment. In retrospect I came to realize that what I was actually experiencing were programming bugs! I still encounter computer bugs, but none quite so memorable as in the early days of SAGE. R. O. WHITNEY San Jose, Calif. INVENTING LANGUAGE, EXAPTING MONEY Ian Tattersall argues in “How We Came to Be Human” that language was a cultural innovation that occurred around 70,000 years (70 kyr) ago. This assumes that language is a generalized ability that arose from our capacity for symbolic 10 SCIENTIFIC AMERICAN APRIL 2002 COPYRIGHT 2002 SCIENTIFIC AMERICAN, INC.
Letters thought; however, Noam Chomsky and his successors have shown that modules for specific aspects of language acquisition are hardwired into the brain. Such complex abilities specifically directed at language must have evolved during a long period, possibly the two million years over which the vocal tract developed. If language was until very recently used only for practical and social purposes, it is unlikely to have left any trace in the fossil record. It seems more reasonable to turn Tattersall’s argument on its head and propose that fully modern humans arose as a result of exaptations in the brain around 70 kyr ago that allowed language to be used for symbolic thought. Tattersall’s idea of cultural innovation is a more pleasant explanation for the emergence of modern humans than the carnage of wholesale replacement. Unfortunately, the disappearance of the Neanderthals and the human record since then make replacement all too plausible. DUDLEY MILES London I don’t understand how Tattersall could conclude that language was invented between 60 and 70 kyr ago. Luigi Luca Cavalli-Sforza and others claim that genetic and linguistic evidence suggests that African and Eurasian languages diverged from a common source about 50 to 70 kyr ago and that Eurasian and Southeast Asian languages diverged 40 to 60 kyr ago. If so, was there enough time for language to become established and diverge into what we see today? Also, language is not purely cultural; there is much that is inborn. Wouldn’t this prevent cultural diffusion or at least dramatically slow diffusion? Let us consider another scenario: the purely cultural exaptation of stone toolmaking to body ornamentation to money. There is evidence that the Neolithic emergence was accompanied by the beginnings of body ornamentation and long-distance trade. Money, in the form of beads and such, would have led to trade, role specialization and new technologies. Money, too, is an adaptation that would have easily spread by cultural diffusion. To “exapt” the language of thermodynamics, perhaps money (stored work) facilitated the rise of novel dissipative systems. LLOYD ANDERSON Chicago TATTERSALL REPLIES: In light of what we know about evolution, it seems most likely that our extraordinary cognitive capacity was somehow acquired as a unit, rather than in a gradual process of modular accretion, for it is plainly wrong to regard natural selection as a long-term fine-tuning of specific characteristics, however much we like the resulting stories. And it’s important to remember that even today we are still testing the limits of this generalized capacity that makes so much possible. As for Miles’s dismal view of human proclivities toward other species (let alone other people), I can only, if reluctantly, agree. BURIED IN STYLE: One of the earliest (about 28,000 years ago) and most ornamented human burials in Europe; beads are mammoth ivory. Anderson’s point about language is equally well taken, although languages tend to change so fast and unpredictably that any uncalibrated chronology has to be suspect. Yes, language seems to be tied up quite intimately with all kinds of other behaviors that are linked in some way to our core cognition, and the invention of money is one more expression of that unique capacity. Money as we are familiar with it today is actually a rather recent innovation and has certainly brought problems in its wake, but the exchange of goods over long distances seems to be a behavior that was established very early in human prehistory. AMERICAN BIOWARFARE One biological-warfare tactic has deep roots in American soil [“Evaluating the Threat,” by Ed Regis; News Scan]. In 1763 Lord Jeffrey Amherst, the British commander in chief for America, maliciously distributed smallpox-infested blankets and handkerchiefs to Native Americans living near Fort Pitt, Pa., and the U.S. Army did the same in the 19th century. ALEXANDER S. WEGMANN Port Angeles, Wash. EDITORS’ NOTE: Regis’s reference to this fact in the original draft of the article was cut for space. ERRATA In the map of South Asia in “India, Pakistan and the Bomb,” by M. V. Ramana and A. H. Nayyar, the scale should have extended from 0 to roughly 500 kilometers, with each tick mark representing an increment of about 80 kilometers. In “Photonic Crystals: Semiconductors of Light,” by Eli Yablonovitch, the major credit for the theoretical discovery of a photonic band gap in face-centered cubic structures and in the scaffold structure should have gone to H. Sami Sözüer, now at Izmir Institute of Technology in Turkey. The creation of the smallest laser should have been credited jointly to Amnon Yariv’s group as well as Axel Scherer’s group, both at the California Institute of Technology. NOVOSTI Photo Researchers, Inc. 12 SCIENTIFIC AMERICAN APRIL 2002 COPYRIGHT 2002 SCIENTIFIC AMERICAN, INC.
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