Water, Water Everywhere
Thank you for Peter Rogers’s timely article on the increasing threat to freshwater resources, “Facing the Freshwater Crisis.” I was, however, disappointed in the headline “Running Out of Water” and accompanying graphic on the cover. I speak frequently to the public about water and attempt to explain the hydrologic cycle. There are several bits of information that people have consistently told me were new to them, including that the cycle works on a global scale, that so little of the planet’s water is readily available for human use and that the total amount of water has been relatively stable for eons. Unfortunately, because many people do not well understand the global, cyclical nature of our water system, they believe that water is literally disappearing. We need to consistently emphasize that water availability is decreasing not because the amount of water has changed but because we are placing greater demands on the resource.
Appalachian State University
In addressing responses to hunger in “developing nations,” particularly in Africa, in “We Can Do More” [Perspectives], the editors advocate more effective aid programs (with policies to better ensure that aid reaches the poor, results in improved roads and farmer education, and affords better seeds, soil conditioning, irrigation, and so on), along with the eventual introduction of genetically modified organisms (GMOs). But these steps taken alone will only exacerbate the long-term conditions of poverty, deprivation and ecological catastrophe. The editors leave out an essential part of improving human welfare in a sustainable manner: control of population growth. To create effective long-term assistance for the poor worldwide, you must first target aid to support government policies that promote family planning and responsible procreation.
GMOs are not the solution to Africa’s hunger. The editors’ support of their use is based on the faulty premise that there is not enough food to feed the world and if only we could increase crop yields, people would not starve. Hunger is primarily a political and economic problem. The original green revolution was an overall failure for the poor throughout the world, and I have little hope for a new GMO-based green revolution. Patented seeds and the chemical pesticides and fertilizers they require benefit the large agribusinesses and not the hungry of developing countries.
Long Beach, Calif.
Aura of Mystery
“Why Migraines Strike,” by David W. Dodick and J. Jay Gargus, claims that 30 percent of migraine sufferers experience an aura (illusions of sparks and lights, often followed by blind or dark spots in the same configuration), whereas 100 percent experience headache. For the past 30 years I have experienced the aura once or twice a year. But I never get a headache.
David E. Ross
Oak Park, Calif.
THE AUTHORS REPLY: As many readers have suggested, aura symptoms may occur without headache. With increasing age, it is not uncommon to retain the aura but lose the headache or to develop aura symptoms without a prior history of headache. This phenomenon has been referred to as “late-life migraine accompaniments” or “migraine equivalents.” The International Headache Society recognizes it as “typical aura without headache” and notes that some individuals, primarily men, only ever experience the aura.