AH, SWEET MYSTERY OF LIFE . . .
I enjoyed September’s “Great Mysteries of Human Evolution” by Carl Zimmer, but I take issue with the statement “Putting a stone ax on the end of a stick to make a spear would have allowed these hominids to become much better hunters, and yet this simple idea apparently never occurred to them.” According to Projectile Technology (Plenum Press, 1997), “a sharpened wooden spear can be used as a digging stick, a lever, a probe, and as a beater for dislodging fruit and nuts from trees. The brittle stone tip of a spear used in these tasks is not only likely to loosen and break but is also far more difficult to repair than a sharpened wooden spear.” Maybe they didn’t use stone-tipped spears because of a superior rather than an inferior ability to reason.
Zimmer’s excellent article provides thought-provoking answers to some of the most familiar questions about human evolution. The question most frequently asked of me as a professor of biology is, “Are humans still evolving?” I explain to my students that evolution is a process that follows many rules, foremost among them that certain random changes in heritable factors provide their possessors with advantages in coping with an ever-changing environment. This survival of the biologically fittest has been the driving force behind human evolution. However, our modern world and its unevenly shared advantages and disadvantages—based on politics, economics, and the availability of medical treatment—have removed the need for any biological advantage. Perhaps some new process will become established, one based on a new set of rules, but the one that has resulted in our present position has ended.
Springville, New York
Near the end of the article on human evolution, the author suggests that the primary limitation on human brain size is female hip structure. This may have stymied our brain expansion for 160,000 years, but I would submit that this evolutionary limitation has already been conquered. Human brain size was limited only until our brains developed the cesarean section, which becomes more common with every generation, allowing virtually limitless brain-growth parameters for the future. The real question is, will human evolution continue to be limited by the ponderous rate of nature or will we overcome even this limitation with our brains? Will genetic engineering and biotechnical or nanotechnological manipulations become the new drivers of human evolution?
In “Great Mysteries of Human Evolution” the question is posed, “Why do we walk upright?” I suggest that the evolutionary pressure for this behavior may be linked to our species’ propensity for using tools as weapons. The individuals who could make full use of their forelimbs would have had a distinct advantage over those whose hands were not free to wield a club or a spear, and within a few generations the trend toward bipedalism could have been well established. It makes as much sense as Kevin Hunt’s theory that we started standing in order to pull down branches.
Your September article on human evolution was clear and beautifully illustrated, but I am amazed that there was no mention of the aquatic ape theory, which has much better answers for some of the questions posed than the establishment theories Zimmer noted. The theory was first proposed in 1960 by Oxford biologist Sir Alister Hardy. He pointed out that none of the features that differentiate hominids from apes evolved in any other savanna primates, which makes it difficult to explain why humans developed them. Some of the these essentially human features include hairlessness, bipedalism, subcutaneous fat, voluntary control of breathing, and a descended larynx, which makes speech possible. Hardy suggested that instead of evolving in a savanna region, our transition from ape to human took place in a watery environment, such as the East African region where Lucy, the best-known example of Australopithecus afarensis, was found. This area became flooded about 7 million years ago and remained underwater for a few million years. If humans did much of their evolving in this region, in a food-rich sea and its wetlands, it would explain why we have a long list of physical features in common with aquatic mammals, such as whales, dolphins, seals, and walruses.
Cold Spring Harbor, New York
CAN YOU HEAR ME NOW?
Kudos to Eric Haseltine for his efforts at getting an answer to the question, “Can Anyone Make Wireless Work?” [September]. As I read I felt trapped in the purgatory of a voice-activated customer-support call. The panel’s responses were no different from what sadly passes for support as provided by the wireless industry. Cynthia Christy alone was on track with her observation: “Consumers don’t care about standards or infrastructure. They want reliable coverage, dependable devices, and value from the services they pay for every month.” Why would I invest time and effort in Wi-Fi when I need to walk 20 feet from my house just to get a signal? The majority of consumers who use wireless technology are not trying to transmit images to a screen or chugging down a triple latte at an 802.11 hot spot. We want a dependable, portable version of Alexander Graham Bell’s original concept.
The proper title for this article should have been: Can anyone make wireless experts answer why wireless doesn’t work? Eric Haseltine asked the most important question on the minds of U.S. cell phone users, only to get the runaround—twice! The industry is so fixated on high-tech gadgetry that it has abandoned customer service. How else can we explain Robert Lucky’s comment that “cellular phone stuff is a done deal” or Peter Shinyeda’s complete ignorance of the problem (“You can call anywhere from any place”). One day, they must be made to realize that cell phones are phones. Until then, discussions of wireless data transfer, video, and 3G are just plain silly.
A BUILT-IN AUDIENCE
Author Steven Johnson skirted the real issue in “Built-in Spam” [September]. Sure, we’re used to advertising in the malls, on TV and radio, and so on. But we don’t pay up front for the privilege of viewing these commercials! If a software developer wants me to view ads, then it should give me the software for free. On the other hand, if I pay hard cash for a program, don’t expect me to quietly accept built-in spam, particularly when it’s on a program that I and millions of others must have in order to use our computers.
David L. Brady