The Population Bomb, in which he predicted that hundreds of millions of people would die of starvation in the 1970s and 1980s.Planet Earth, now home to about 6.5 billion human beings, has thus far disproved the doomsayers. In 1798, Rev. Thomas Robert Malthus predicted that population would outrun food supply on the assumption that human numbers would increase at a geometric rate while food would be limited to arithmetic increases. Then, in 1968, Stanford University professor Paul R. Ehrlich issued a similar warning in his book Both men underestimated humanity’s resourcefulness—as well as its scientific and technological acumen—in figuring out how to provide for its growing numbers. Still, there’s little doubt that the Earth’s human carrying capacity has a limit. And growth can’t continue indefinitely without more of the significant environmental health impacts we are already seeing. In addition to documenting exactly how much growth is occurring, scientists are now interested in trends reflecting where such growth is occurring and the effect of factors such as consumption rates and migration on sustainability of the Earth’s resources.The Population Bomb—Ehrlich placed the limit at 500 million.Nobody really knows what the planet’s human carrying capacity is. Some, like Cornell University ecology and agriculture professor David Pimentel, contend that the Earth has already passed that point. Citing high malnutrition rates in the world, Pimentel estimates that the Earth’s carrying capacity—providing a quality life for all inhabitants—would appear to be about 2 billion. Other estimates go to both extremes. In a 1995 Cato Institute essay titled “The State of Humanity: Steadily Improving,” Julian L. Simon, the late University of Maryland economist, wrote, “We have in our hands now—actually in our libraries—the technology to feed, clothe and supply energy to an ever-growing population. . . . Even if no new knowledge were ever gained . . . we would be able to go on increasing our population forever.” On the other end of the spectrum, in 1971—three years after writing Others suggest that humans are already finding a way to take care of the population problem as evidenced by declining birth rates everywhere in the world. Declining birth rates don’t necessarily translate into declining populations, however. The United Nations (UN) Population Division projects that by 2050, global population could reach 9.1 billion.This greater global population will differ from the current one in several ways. The population growth of the developed world has slowed to a crawl; fertility rates are on the decline and in some countries, such as Italy and Japan, population itself is projected to peak in five years. But poor countries will experience large increases for decades to come. Meanwhile, the UN points out that in 2007, for the first time in history, the global population will cross over from being predominantly rural to mostly urban, and that that trend will continue indefinitely.“Most of the growth that’s going to happen in the next twenty, thirty years is going to be happening in the poor countries—it’s going to happen mostly in the cities, and mostly in the slums of the cities,” says John Bongaarts, vice president of policy research at the nonprofit Population Council. “Most of the next two or three billion people will end up in the slums of the poorest countries.”Like many demographers, Bongaarts sees the decline in fertility rates, mostly in the industrial world, as the emerging worldwide norm. This means, he says, that at some point the poorer countries will reach the same stabilization point that the developed world has achieved and that global population will one day decline. He projects that peak will be reached at about 9.5 billion people.Perhaps surprisingly, population’s relationship to health and environmental impacts is often ignored or glossed over by policy makers. In part, says Robert Engelman, vice president for research at the policy action group Population Action International, there’s a belief that “population will take care of itself.” But there’s also a reticence to talk about population because it gets tied up in politics, including the abortion debate.Julie Starr, a population and environment specialist with the National Wildlife Federation, says she was surprised to see that the eight UN Millennium Development Goals that were set in 2000 failed to make any mention of population growth and family planning. These goals summarize all the development goals agreed to at international conferences and summits during the 1990s, with a target achievement date of 2015. “Each of the goals has specific targets, and population is mentioned nowhere—not even in goals that deal with maternal health and poverty,” she says. “Our message is that you can’t do anything about environmental sustainability if we don’t address population.”“There’s been a lack of attention to the fact that population continues to grow in the world at a rate that is certainly unsustainable,” Engelman says. “And population is connected to environmental conditions everywhere. There really isn’t any environmental area that you can look at and say that it’s completely irrelevant to the number of people living in a particular ecosystem or watershed.”An international group of scientists who took part in a major new international study, however, apparently wants to see greater attention paid to population in future discussions about environmental sustainability. The Millennium Ecosystem Assessment, launched by UN secretary-general Kofi Annan in 2000 to assess the impact that environmental changes would have on achieving the Millennium Development Goals, involved the work of 1,360 scientific experts who aspired to measure the environmental impact that people are having on the Earth.Ecosystems and Human Well-Being: Synthesis, released in March 2005, which is one of several periodic reports scheduled for release through the end of 2005. This report examined the “services” that ecosystems provide  and concluded that 15 of the 24 services are being degraded or used unsustainably. It suggested that the various environmental declines comprise a roadblock to achieving many of the Millennium Development Goals, including those calling for ensurance of global environmental stability, poverty alleviation, and food security.One document to emerge from the assessment process is Ecosystems and Human Well-Being: Synthesis and explicit in a section in which it is identified as one of five “indirect drivers” that are altering ecosystems. Walter V. Reid, director of the assessment project, says ecosystem health is affected by two kinds of pressures that humans exert: changes in demand for (and consumption of ) an ecosystem’s specific services, and changes in emissions that might harm the ecosystem. “Obviously, both change in demand and change in emissions are closely tied to the combination of population change and economic growth,” he says.The role of population in causing these declines is implicit throughout To Reid, the most troubling development regarding population trends and their environmental impact is the fact that the greatest population growth is now occurring in environmentally fragile areas, like drylands and mountainous regions, where water is scarce and the soil is generally poor. In those areas, he says, “if you have high population growth that is overtaxing the capacity of the soils to provide food, you have high rates of soil erosion and depletion, and there’s just no buffer. And if you need more water, there’s just no buffer of water even to begin with.”Demographers and social scientists use the term “poverty trap” to describe such areas, which are characterized by classic vicious cycles. “The pressure to degrade resources is insurmountable,” Reid says. “People don’t have other options. And when they degrade resources, that leads in the long run to higher levels of poverty and infant mortality and lower income, which leads to greater pressure to degrade resources.”Another population trend emphasized in the March report is the movement of people to coastal areas around the world. Coastal ecosystems—marshes, mangroves, reefs—are extremely important contributors to human well-being, serving as breeding and nursery grounds for many species and as erosion prevention buffers between land and sea. Yet these benefactors are rapidly being destroyed. According to Reid, 35% of the world’s mangroves and 20% of its coral reefs have disappeared in the last two to three decades due to human pressure.The assessment makes a variety of recommendations for policy makers—remove environmentally harmful subsidies to agriculture and fisheries, improve management of ecosystem services in regional planning decisions, provide public education about the importance of ecosystems, promote greener technologies, and more. But Reid believes that if the report is to have an impact, there must be some kind of repeating assessment process. He thinks that a mechanism should be created so that the subject is revisited in similar fashion every 10 years.Roger-Mark De Souza, technical director of the Population, Health, and Environment program at the Population Reference Bureau, points out that another important trend in the developing world is its high and growing proportion of young people. In sub-Saharan Africa, for example, the proportion of people under 15 to people over 65 is 44% to 3%, according to the bureau. In Latin America, the numbers are 32% younger people compared to 6% older people. “That means that we will have continued population growth for some period of time because those young people of today are tomorrow’s parents,” he says. “We call that ‘population momentum.’”In addition to their raw numbers, De Souza says, ever-increasing globalization means the growing ranks of young people in the developing world may be driven to consume more than their parents do. “They access images about life in other parts of the world on television and the Internet, and they desire to live that way,” he explains.Population Bulletin, published by the Population Reference Bureau, in 1999 the average North American consumed more than 15 times the energy of the average African .“Most people accept the notion that major, long-term environmental problems will stem more from consumption than from population growth,” Kates says. “Population growth is one of the forces that drives consumption. But there are a whole host of other forces as well—growing income, changing diets, the creation of transnational markets.”Geographer Robert Kates, a visiting scholar at the Harvard Center for International Development, contends that consumption rates are actually more important than population. Currently, a huge per-capita consumption disparity exists between rich and poor nations. According to the September 2003 Kates argues that potential growth rates for consumption around the world are much greater than the better-known predicted rates for population growth. Therefore, he suggests, the number of people isn’t as important as what those people do. “The increase in the number of people is clearly slowing down everywhere in the world,” he says. “But the increase in consumption by those people is going up everywhere, except in Africa, and there’s no sign of diminution in the future. So there will be a shift from long-term historic concern about population to a growing concern about how, what, and where we consume.”Others, however, say while paying attention to consumption is indeed a critical force, its importance should not sideline the question of where and at what level population growth will end. “If our [global] population had stabilized where it was in antiquity, at about two hundred fifty to three hundred million, our consumption probably wouldn’t make too much difference,” says Engelman. “But it’s precisely because human population has gone where it is that consumption has the global impacts that it has. How much ‘environmental space’ each of us has to consume sustainably has everything to do with how many of us there are.”Whether one chooses to attribute impacts to human numbers or human behavior, the fact remains that the world’s population—its numbers, its movement, its actions—is having a profound impact on human and environmental health. A variety of organizations and individuals, including the UN and other international agencies, nongovernmental organizations, scientists, and demographers, have identified many of the ways in which this is happening.AAAS Atlas of Population and Environment, predicted that the situation is “likely to be worsened by the deteriorating quality of water, polluted by industrial wastes and sewer discharges.”Engelman points out that the amount of fresh water on Earth is roughly the same today as it was 3,000 years ago, while population has increased 40-fold. Declining water tables are a growing problem in much of the world. According to the Population Reference Bureau, 12 of the world’s 15 water-scarce countries are in the Middle East and North Africa, comprising an area that experienced more than a doubling of population—from 173 million to 386 million people—between 1970 and 2001. Growing additional food to nourish growing populations will rely heavily on irrigation, placing greater strain on water tables. The Millennium Ecosystem Assessment reports that usage levels of fresh water for drinking, industry, and irrigation are “unsustainable.” The American Association for the Advancement of Science (AAAS), in its 2000 According to the Population Reference Bureau, human activities during the 1990s resulted in the deforestation of 563,709 square miles of land, roughly the equivalent of Colombia and Ecuador combined. Most of the deforestation occurred in Africa and South America, where forests have been cleared for cropland, fuel use, and commercial sale of wood products. The environmental and human health impacts of deforestation are varied, including increased propensity for flooding, loss of medicinal species and fuel wood, soil erosion, and exacerbation of climate change as carbon is released back into the atmosphere. Related to deforestation is the issue of biodiversity loss. The World Conservation Union estimates that nearly one-fourth of the mammals and one-eighth of the birds on Earth are now threatened with extinction.“The fishery story is a sad case of overuse by humans,” says Bongaarts. “Fish populations have collapsed in many parts of many oceans, and lower-quality fish are replacing them.” According to the AAAS atlas, the world’s marine catch increased fivefold between 1950 and 1990, but has remained stagnant ever since. The Millennium Ecosystem Assessment took an even bleaker view, finding that harvests have been declining since the late 1980s .The link between population growth and climate change is less clear. Engelman points out that the vast majority of climate change is driven by emissions from industrialized countries, the populations of which will soon peak or have already done so. But poor countries are rapidly expanding their industrial capacity in response to out-sourcing by industrialized countries, and their share of climate change–related emissions will increase rapidly in coming years, raising the need for international agreements on emissions reductions, Engelman says.Air Quality Guidelines, said that outdoor air pollution in Western Europe and North America has improved since 1970, but in less developed countries air pollution in the large cities—including Delhi, Jakarta, Mexico City, and many Chinese cities—is severe. So is its impact on public health. The World Resources Institute studied the health effects of air pollution in cities in poor nations and said in the 1999 report Urban Air Pollution Risks to Children: A Global Environmental Health Indicator that it was responsible for 50 million cases per year of chronic cough among children under age 14.The World Health Organization (WHO), in its 1999 Population Bulletin. Encroachment into wildlife habitats also exposes humans to new diseases. “Increased contact with wildlife and associated diseases, combined with international trade in livestock, has led to outbreaks of diseases such as rinderpest [a viral disease affecting ungulates] in Africa and foot-and-mouth disease in Europe,” stated the report.Human population growth and migration has also fostered the emergence of many infectious diseases by increasing population density. This is especially true in urban areas, where illnesses such as dengue and cholera are becoming more common, the Population Reference Bureau reported in the September 2003 AAAS Atlas of Population and Environment, says one of the reasons for the study is that the United States, in a departure from other industrialized nations, is experiencing significant population growth and will continue to do so.The Center for Environment and Population (CEP), a nonprofit research and public policy organization, will be releasing a national report this fall that will explore the relationship between U.S. population trends and their impact on health and the environment. Victoria Markham, director of the CEP and executive editor of the Where the AAAS atlas was one of the first large efforts to tie known data about environmental change to population, the upcoming CEP report will do the same sorts of comparisons within American borders. Markham says the latter report will focus on several human population variables that relate to environmental impact—population growth, distribution, movement, and makeup, as well as household demographic trends and consumption rates—and apply them to the nation’s four census regions.2004 World Population Data Sheet call for the United States to remain third behind China and India for decades to come, while two other current industrialized countries, Russia and Japan, will be dropping out of the top 10 and leaving the United States as the only currently industrialized country on that list by 2050.With a population of 298 million, the United States is the third most populous country in the world, behind China (population 1.3 billion) and India (population 1.1 billion). Projections in the Population Reference Bureau’s “Couple our growing population with our disproportionately high rate of resource consumption, and you have a volatile combination,” Markham says. “The United States turns out to be a world leader in terms of per-capita global environmental impact.”Population Change and Distribution, 1990 to 2000. But while more Americans than ever are living in metro areas, most of the growth is occurring outside center cities, in outlying suburban areas.Like the rest of the world, the United States is becoming ever more urbanized, but at a more advanced level, as 80% of Americans now live in metropolitan areas, according to the 2001 U.S. Census Bureau report Markham says this outcome—sprawl—can be illustrated by the fact that while the American population has grown by 17% in the last two decades, the land area converted to metropolitan use grew by 50%. “Air pollution is very closely tied to population,” she says. “Transportation is the fastest growing energy-use sector in the United States, and it’s particularly tied to this sprawled development because people have to drive more and drive farther. The result is increased carbon dioxide emissions.”Another trend is a continuing higher rate of population increase in the South and West, compared with the Midwest and Northeast. This trend largely reflects the movement of the industrial infrastructure from the North to the South and West starting in the 1960s for various economic reasons, such as lower taxes and lower labor costs. In terms of environmental impact, the population growth in the West is especially worthy of concern because of the region’s fragile water supply. “Population growth couldn’t be happening in a more environmentally vulnerable place in the United States,” Markham says. The Ogallala aquifer, which lies under eight western states and is the largest groundwater system in North America, accounting for 20% of all irrigated land in the United States, is down one-third of its capacity and is shrinking at the rate of a foot per year, according to Markham.Meanwhile, Americans are living in ever larger per-capita household space, which exacerbates energy consumption. The CEP report will describe the continuing decline in number of persons per household, which translates into more households. At the same time, the physical size of American homes is growing ever larger. According to Markham, the proportion of houses of at least 3,000 square feet more than doubled between 1988 and 2003; during that same time, the number of new houses smaller than 1,200 square feet declined. And lot sizes of new one-family houses outside the country’s metropolitan areas rose by 6% in the past 10 years, according to the Census Bureau. The increase in the number of houses overall combined with larger lot sizes means more land is being used for residential development than ever before.Discussions about burgeoning human populations and their impact on health and the environment abound in gloomy data and prospects of doom. But experts also suggest there are reasons to be somewhat optimistic. First, they say, humanity has proven itself to be more resourceful than Malthus and Ehrlich gave it credit for being. “Basically, forty or fifty years ago, the whole world was growing rapidly,” Bongaarts says. “There was a huge concern about potential food shortages and environmental problems. But birth rates have declined, so growth is not as rapid as people thought it would be.”Even though the rates are declining in poor countries, they’re still higher than the acknowledged replacement figure of 2.1 children per woman. Still, Asian, Latin American, and Caribbean women are bearing children at a rate of 2.6 children per woman in 2004 compared to about 5 per woman in 1970, according to the UN Population Division. African women still have 5 children on average, but that’s down from 6.7 in 1970. Europe has dropped from 2.2 children per woman to a population-slashing 1.4. In the major world regions, only North America has not seen declining birth rates. North American women averaged 2.0 children in 1970 and the figure was the same in 2004.To many observers, the decline in global birth rates is clear proof of the effectiveness of family planning programs. “I think the greatest proportion of demographic research points to the worldwide effort to make contraception available, which was clearly desired and was in fact picked up and used,” Engelman says.Bangladesh Demographic and Health Survey 2004, published by the U.S. Agency for International Development, birth rates in that country have declined from 6.3 children per woman in the early 1970s to 3.0 children in 2004.Lars Bromley, a senior program associate in the AAAS Office of International Initiatives, has come to the same conclusion. “If a country works to reduce its birth rate, it’s not a foregone conclusion that they’re destined to have twelve children per woman,” he says. “Places like Bangladesh and elsewhere have really performed miracles over the last generation.” According to Another improvement, Kates points out, is that although the total amount of energy consumed continues to rise, the world is reducing its “energy intensity”—that is, the amount of energy it uses per unit of production—at a rate of about 1% per year. This is mostly due to improved energy-saving technology.But as the scientists who conducted the Millennium Ecosystem Assessment conclude, a broad international response is necessary to deal with the environmental declines caused by increasing human pressure. They didn’t make predictions about what may happen, but they did offer four possible future scenarios. The first, “Global Orchestration,” depicts a world that makes economic development a priority and emphasizes solving environmental problems rather than preventing them in the first place. The second, “Order from Strength,” represents a fragmented world concerned primarily with security and protection, where the approach to the environment again is reactive. The third, “Adapting Mosaic,” would deemphasize economic development and put priority on the health of ecosystems, largely through the strengthening of local management strategies. The fourth scenario, “TechnoGarden,” describes a future in which a unified world relies on environmentally sound technology and highly managed, often engineered, ecosystems to deliver ecosystem services, and that achieves both strong economic growth and a healthier world.Reid believes that the work on which direction the world should go must start soon. And he believes the debate must focus more on population than it has to date. “Population is one of those issues that’s so central and so politicized,” he says. “Sometimes you worry that people are ignoring it because of the political side of it, but it’s critical that people keep thinking about it and about steps that can be taken to address population problems.”Over the past century and especially over the past 40 years, people have effected vast changes in the global environment. Those people most directly affected by environmental challenges, from water pollution to climate change, are also the poorest and least able to change livelihoods or lifestyles to cope with or combat ecological decline. Some signs of ecological change include:Source: UNFPA. 2004. State of World Population 2004: The Cairo Consensus at Ten—Population, Reproductive Health and the Global Effort to End Poverty. New York, NY: United Nations Population Fund.


The tiny hominid bones, which a joint Australian-Indonesian team unearthed in 2003 on the Indonesian island of Flores, have quickly become as celebrated (and derided) as any find in the tempestuous history of human paleontology. Homo floresiensis? The tiny hominid bones, which a joint Australian-Indonesian team unearthed in 2003 on the Indonesian island of Flores, have quickly become as celebrated (and derided) as any find in the tempestuous history of human paleontology. The mystery that shrouds these ancient skeletons, nicknamed hobbits after the diminutive characters in J. R. R. Tolkien's novels, seems to deepen with every study published. Two main camps have emerged, each certain they can settle the question. But many other paleoanthropologists confess they still have no idea.Who—or what—is H. floresiensis, based primarily on a single near-complete skeleton of one very small individual with a very small brain, known as LB1. Compared to H. sapiens, LB1, whose age was estimated from tooth wear at about 30 years, was only one meter tall—about the size of a 4-year-old H. sapiens child—with a brain the size of a newborn's. Although there are also fragments of eight other small individuals, they provide no information about brain size, nor is much skeleton preserved. Nonetheless, they possess a combination of features never before seen in human fossils, which makes it credible that a previously unknown population of people smaller than today's pygmies lived on Flores between 90,000 and 12,000 years ago.The discovery team declared their find a new human species, H. floresiensis…could be the first human example of island dwarfing.H. floresiensis, the discovery team claimed, could be the first human example of island dwarfing. This phenomenon, thought to be evolution's response to limited resources, is known for other mammals, including dwarf elephants from Flores itself. But this is not the only possible conclusion. A long-awaited paper, which appeared online in Proceedings of the National Academies of Sciences of the United States of America (PNAS) on August 23, 2006, offers a radically different interpretation of these skeletal remains.Stone tools found at the site raise the possibility that hobbits had culture, even though LB1's brain size would make a chimpanzee sneer. The lead author of the PNAS paper is Teuku Jacob, the “Grand Old Man” of Indonesian paleoanthropology. Jacob was not a member of the discovery team, but his lab at Gadjah Mada University in Yogyakarta on Java is home to many hominid fossils discovered in the region. For reasons still unclear, soon after the journal Nature published the discovery papers in October 2004, the hobbit bones were conveyed to Jacob's lab from the Center for Archaeology in Jakarta, about 450 kilometers away.The result was an international uproar played out in the media. Australian members of the discovery team were irate because their finds were moved without their permission and were no longer available for study. Other paleontologists expressed alarm at what seemed like one group of scientists making off with finds of another. Jacob said he had been invited to take them.H. sapiens after all. How to account, then, for the diminutive size of LB1? Jacob concluded that LB1 suffered from microcephaly, a disorder resulting in abnormal development of the brain and, often, body. His diagnosis was backed by Indonesian colleagues and also a few Australian and American researchers whom he permitted to study the bones.Moreover, Jacob pronounced that the bones did not belong to a new hominid species, but were those of After complex negotiations, most of the bones were returned to Jakarta in February 2005. But the uproar revived when discovery team member Michael Morwood of the University of New England  protested that LB1's pelvis was smashed and another hobbit's jaw was broken and repaired clumsily. Jacob responded that the bones were fine when they left his lab.When the criticisms of Jacob and his collaborators were finally published in August 2006, they reiterated previous claims that the LB1 skull was unnaturally asymmetrical, showing signs of deformity. The paper also reported that many LB1 traits resemble those of Austromelanesians, and some are similar to Rampasasa pygmies living near the dig site at Liang Bua cave. Hobbits are probably related to them, the authors said, and therefore not a new species. Moreover, LB1 was microcephalic. The authors proffered specific anatomic details to establish their case. However, even when researchers agree on details of hobbit anatomy, it seems they can't agree on their meaning.sapiens; no other hominids have them. Everyone agrees that the two hobbit mandibles lack chins. But the PNAS paper asserts that appearing chinless does not necessarily mean that the hobbits were not H. sapiens. The paper included a photo of a live Rampasasa pygmy with what the authors termed a negative chin.Take the chin. Chins mark a skeleton as But paleoanthropologist Jeffrey Schwartz from the University of Pittsburgh  points out that although having a chin signifies our own species, there are individual exceptions, so chinlessness doesn't say much. “Having a chin provides information. Not having a chin doesn't.”…it's pretty much the usual fossil furor…sapiens teeth. Not only are they small, according to paleoanthropologist John Hawks of the University of Wisconsin , hobbit teeth are small in the sapiens pattern: first molars are biggest and third molars smallest. H. erectus and Australopiths have different patterns.If chinlessness can't illuminate the discussion, what about teeth? Hobbit teeth are a strong reason to think they may not be a new species. Everyone agrees that compared with other hominids, which have big teeth, hobbit teeth are small, like Robert Eckhardt of Pennsylvania State University , an author of the PNAS paper, argues that chance convergence of traits in different hominid lineages is unlikely to explain these similarities. Coauthor Etty Indriati, colleague of Jacob's at Gadjah Mada, notes that hobbit teeth also share features with Rampasasa pygmy teeth, such as rotation of the premolar, that imply genes in common.Ralph Holloway, paleoanthropologist at Columbia University , who shares the critics' belief that LB1's brain was pathological, nevertheless was dissatisfied with the PNAS paper. “It's the kind of paper that should be published, but they could have done a better job on it.” Hobbits, he says, should have been compared to several populations. Indriati responds that it is sounder scientifically to compare LB1 with Flores pygmies, its closest neighbors in both space and time.Holloway agrees that LB1's cranium is asymmetrical. But he and others also agree with University of New England co-discoverer Peter Brown that asymmetry could result from being under several meters of deposits for several thousand years, plus the difficulties of recovering and reconstructing bones described originally as like wet blotting paper. Hobbit bones were never fossilized. “To use that asymmetry to make a case for pathology, you know, I don't think that's a very strong argument,” Holloway says.The PNAS authors reinforced the case for asymmetry with striking composite photographs of LB1's face see the . They disapiens or erectus, but still may have had human-like thinking abilities because the prefrontal cortex and temporal lobes seemed expanded. The region, known as Brodmann area 10, is thought to be the seat of higher cognitive processes like memory, communication, and planning.A March 2005 paper in the journal Science, whose authors include a subset of the discovery team, reported that a virtual endocast of LB1's cranium, which has brain features imprinted on it, suggested that hobbits were not simply miniature versions of By contrast, Holloway, who has also studied an LB1 endocast, says the brain's small size and some other features hint at pathology. Parts of area 10 called the gyri recti seem too thin, he reports, and he has never seen a human endocast so flattened out before, which also suggests abnormality. Like several other researchers, Holloway has tried (and failed) to find direct correspondences between LB1's cranium and those of people with microcephaly. Microcephaly, meaning simply small head, is an umbrella term for a miscellany of conditions with scores of different genetic and environmental causes and myriad manifestations. The most recent study, published online in Anatomical Record on October 9, 2006, concludes that “it is not possible to match any of these syndromes exactly with the LB1 fossil,” although the authors argue that some microcephalic syndromes share features with LB1, including stature, head size, and anomalies of jaw and teeth. As all the studies point out, nothing so far unearthed in the clinical literature or the fossil record matches LB1's peculiar head. Those negatives, of course, don't rule out deformity, especially deformity unique to the hobbits; isolated populations routinely develop distinctive abnormalities.Homo) fossils known only from Africa—the Australopithcines.Debbie Argue of Australian National University  and co-authors of an October 2006 paper in the Journal of Human Evolution say LB1 is probably not microcephalic, and they endorse the designation of a new species. They also say the hobbits are not pygmy-like. They suggest instead (as have others) that, whereas LB1's cranium is not like anything else in the hominid fossil record, some other hobbit bones resemble much older early human  have analyzed hobbit postcranial material at recent paleoanthropology meetings. They have found limb proportion convergences with Lucy, the most famous member of Australopithecus afarensis. Still, they say, shoulder characteristics more closely match early H. erectus.The original Nature paper had speculated that hobbits might have been a dwarfed descendant of H. erectus is not geographically outrageous. H. erectus had been in the region for nearly 2 million years; in fact, the type specimen was found more than a century ago on the Indonesian island of Java.What is a hobbit?At least a genetic link to erectus, whose brain was 75% of the size of ours, there is no evidence whatever that small-brained Australopiths (35% the size of ours) ever ventured out of Africa—let alone invented boats and sailed off to Indonesia more than 3 million years ago. The Argue et al. paper speculates on ways very early hominids might have migrated to the region. Something like this astounding seagoing scenario—a really, really ancient mariner—seems to be required if H. floresiensis had Australopith ancestry.But, unlike big-brained Hawks speculates that this quandary might go away if we knew more about the environmental and developmental factors that determine human body size. “We have no idea what explains body size, and the hypotheses about this are not compelling.”Maybe LB1's pelvis looks Australopithecine, Hawks suggests, not because the hobbits descend from a seafaring Lucy, but because that's what the pelvis of a very small human biped looks like. “It has the virtue of not depending on external events to explain it,” Hawks says. “It's just a consequence of being small. You still have to explain why they're small.” If we knew why growing big or small was advantageous, we might learn whether island dwarfing applies to people as well as elephants.erectus was subjected to island dwarfing? Would ancestral Australopithecine features emerge, perhaps as a result of changes in fetal development? “We'd like to know that, but you know, we just don't.”Richard Potts of the Smithsonian Institution  suggests something similar. What would happen, he wonders, if an early, smaller-brained The debate over the hobbit brain has been fueled by stone tools found at the site. A commentary accompanying the original two papers suggested that some were like tools associated elsewhere with modern humans. This suggested to others that hobbits had a complex culture.Stone tool experts, however, say the tools are not particularly sophisticated. They are simple, made using techniques that hominids have used for millions of years and humans are still using today.erectus remains have been found on Flores so far, but paleoanthropologists assume they made and used the tools. The paper compared the very old tools with those found at Liang Bua and noted specific similarities.A team led by Adam Brumm of Australian National University has tried to show that hobbits were part of a line of Flores tool makers who had been chipping sharp flakes from stone for upwards of 700,000 years. The researchers based their analysis on more than 500 stone artifacts excavated at another Flores site 50 kilometers from Liang Bua and dated between 800,000 and 740,000 years ago. No The Flores tools are unique but also simple, according to Potts. “The tools we see on Flores, the older as well as the younger, cannot be exactly matched with anything that's known anywhere else” he says, “but the overall strategy of the technology and the overall size of the materials is consistent with what we find in mainland China.”Harold Dibble of the University of Pennsylvania Museum agrees. They would fit perfectly at a million-year-old site, he says, but also are a type made by native Australians today. “These are simple tools,” says Dibble, “Could they have been made by a small brain? Sure.”H. floresiensis debates have been marked by a degree of acrimony that may seem excessive and even a bit scandalous to outsiders. But a number of paleoanthropologists opine that it's pretty much the usual fossil furor—even though it's been punctuated by public name-calling, a high level of rancor, and exceptionally gaudy episodes like the hobbit bones' unanticipated travels.“I don't think there's anything special about this dispute except that it's taking place in a particular cultural context of Indonesian politics, which science gets drawn into, just as it does in every other country, at least certain fields of science,” says Potts. “There are aspects of etiquette and the way of treating other people that may represent a bit of a clash between the Australian principal investigators and the Indonesian science community, which tends to be a little bit less, well, freelance about such things. I think that there may be a bit of a culture clash there.”H. sapiens, “sent out to fetch the wood or the occasional dead rat, bring it back, whatever!”There are also other theories about LB1 and compatriots. Holloway, for example, says he hasn't given up on his notion that hobbits may have been taken care of and kept as pets by other Flores The most extreme proposition comes from Schwartz: “It's an interesting assemblage of bits and pieces that probably represent different kinds of hominids and maybe even some non-hominids,” he argues. “It's more interesting to me that there might be these different morphologies represented, and the implications of that, than to do a Rube Goldberg hominid and say, ‘Look how weird this is.’”H. erectus. Instead, the most likely ancestor of H. floresiensis was small-bodied and small-brained. “This is not the same as saying the ancestor was an Australopithecine.”“To be very blunt, this is just stupid,” says co-discoverer Peter Brown. For example, he explains, LB1's arm articulates with the skeleton, meaning they are from the same individual and not different taxa. But Brown thinks LB1's skeletal proportions and brain size are unlikely to be due to dwarfing of DNA analysis might help, but prospects are gloomy. The site is hot and wet, perfect for destroying genetic material. There's been at least one effort to find DNA in hobbit bone, carried out in the lab of ancient DNA specialist Svante Pääbo of the Max Planck Institute . It failed.So on present evidence, the debate about whether hobbits were a different kind of human or simply deformed can't be settled. It is even possible that both sides are partly right. Hobbits are so different from anything else in the hominid record that calling them a new human species is by no means crazy. But even some scientists who buy the new species argument think there may have been something wrong with LB1 and that the much-disputed brain is indeed abnormal.What is the hobbit? “I don't know,” Holloway admits, and he has plenty of company. But, he observes, the puzzling hobbits don't change the major outlines of human evolution. “I think it's sort of a side issue.”


Even though traffic-related death rates in the United States and other high-income countries have been declining steadily for several decades, death tolls on the roadways of the world’s poorer countries have been skyrocketing. The number of motorized vehicles has been escalating in developing countries, where roads (often poorly built to begin with) are shared by pedestrians, animal-driven carts, rickshaws, and bicycles, and traffic safety laws are weak or inadequately enforced. The result—an alarming increase in death and injury on the roadways of the world’s poorer nations—is now attracting the attention of international organizations as a major public health problem.World Report on Road Traffic Injury Prevention, an exhaustive examination of the global problem and potential solutions, culminating in a call for action at both the national and international levels. A week later, the United Nations (UN) General Assembly devoted a plenary session to the global crisis in road safety for the first time in its history, discussing, among other things, how to implement the report. Then, in May 2004, at the WHO 57th World Health Assembly meeting in Geneva, delegates accepted resolution EB113.R3, “Road Safety and Health,” calling for the WHO to act as a coordinator on road safety issues within the UN system, working in close collaboration with UN regional commissions.In recognition of this global problem, the World Health Organization (WHO) designated “road safety” as the theme of World Health Day 2004, held April 7. The same day, the WHO and the World Bank released the As the WHO/World Bank report makes clear, the increase in traffic deaths and injuries in the world’s poorer nations has been evident for years: global traffic deaths have risen from approximately 990,000 per year in 1990 to nearly 1.2 million per year in 2002, with 85–90% of these deaths occurring in low- and middle-income countries. Citing a study that examined changes in traffic fatality rates in various countries between 1975 and 1998, the report noted that during that time span Canada’s road fatality rates declined by 63.4%, Sweden’s by 58.3%, and those in the United States by 27.2%; the reasons for these declines have been multifold. At the same time, traffic fatalities increased by 237.1% in Colombia, by 243.0% in China, and by 383.8% in Botswana.Furthermore, the report predicts that if nothing is done to stop the trend, it will rapidly escalate. By 2020, predict the WHO and the World Bank, if appropriate actions are not taken, overall global traffic deaths will increase by 67%; an 83% increase in poorer countries will offset a projected 30% decrease in high-income countries. In 1990, road traffic injuries were the ninth leading contributor to the global burden of disease, according to the report. Without appropriate action, by 2020 road injuries are predicted to be the third leading contributor.Many physicians and public health professionals have been sounding the alarm for years and voicing frustration over the lack of international response. Samuel N. Forjuoh, a Ghanaian-born physician and professor of family and community health at Texas A&M University College of Medicine, believes that part of the problem has been that road crashes are simply not seen in the same way as diseases. “For a long time, injuries were considered haphazard events, acts of God,” he says. “There was a belief that there was nothing you could do about them.”Another reason is that car crashes occur one at a time, says Mark L. Rosenberg, executive director of the U.S.-based nonprofit Task Force for Child Survival and Development and former director of the Centers for Disease Control and Prevention’s (CDC) National Center for Injury Prevention and Control. “You have three thousand people a day dying in car crashes,” he explains. “If you had three thousand people a day dying in one building that collapses or in a few big airplane crashes, it would get much bigger headlines.”Still another reason is a sense of fatalism on the part of some observers. Rosenberg explains, “People say, ‘Oh, motor vehicle deaths are just what happens when you start development in a country. You build roads, you bring in cars, and this is inevitable.’ But nothing could be further from the truth. It’s not inevitable; [these deaths] are completely predictable and preventable.”The Perfect Storm, which told how a rare combination of meteorological forces resulted in a monstrously destructive force, to describe the escalation in traffic deaths and injuries in poorer countries. “More and more motorized vehicles are being added to roadways that are inadequate,” he says. “You have these mixes of vulnerable pedestrians and motorized traffic on main roads with no center barriers. The roads are poorly marked, and they go right through villages. You have situations where people don’t know how to drive, they don’t obey laws, and even if you have laws, they’re not enforced. So you have this lethal mix, and into this we are adding more and more cars, accelerating the rate of injury and death as these cars are added. You have the ‘perfect plague.’” Rosenberg says this plague is also perfectly predictable because “we know how quickly the motor vehicle manufacturers are planning to increase their production in these ripest of markets.”Rosenberg borrows from the popular book and movie World Report, a large portion of the motor vehicle increase in poorer countries has been in the number of motorcycles, minibuses, and trucks. And their increased presence on the roadways of those countries has been overwhelming in many instances. Since 1990, the number of motor vehicles in China, for instance, has quadrupled to more than 55 million. In Thailand, the number of motor vehicles nearly quadrupled between 1987 and 1997.According to the The new and growing mix of two-wheeled motor vehicles, larger multi-passenger vehicles, traditional wheeled vehicles, and pedestrians all often using the same roadways has created patterns of traffic death and injury that are much different from those in high-income countries. The WHO/World Bank report points out that while most of the people who die as the result of traffic crashes in the developed world are passengers in vehicles, traffic crashes in poorer countries are more likely to involve pedestrians and motorcyclists. The report states that between 1977 and 1994 in the city of Nairobi, for instance, 64% of traffic fatalities were pedestrians.Another characteristic of poorer countries is that crashes are far more likely to result in deaths than crashes in high-income countries. Rosenberg explains, “The victims [in developing nations] are much, much more vulnerable: they are pedestrians or bike riders with nothing to protect them.” Further, says Michael R. Reich, a professor of international health policy at the Harvard School of Public Health, the typical U.S. car crash involves the driver running into a tree or into another vehicle. In contrast, crashes in poor countries typically involve pedestrians or people in poorly maintained multi-passenger vehicles, such as mini-buses crammed with 20–30 people and no seat-belts. According to “Road Traffic Injuries in Developing Countries: Strategies for Prevention and Control,” a resource paper by Reich and Harvard colleague Vinand Nantulya, 10,000 U.S. crashes result in 66 deaths; but in Kenya, the death rate per 10,000 crashes has been as high as 1,786, and in Vietnam it’s reached 3,181.A variety of other factors lend to the troubling numbers in poor countries. Forjuoh believes that low literacy rates play a role because many drivers can’t understand road signs. David Sleet, associate director for science at the CDC National Center for Injury Prevention and Control and a coeditor of the WHO/World Bank report, contends that many pedestrians in developing countries have never driven a car and don’t understand the basic “rules of the road” governing motorists. They also are inexperienced in judging oncoming vehicle speeds and stopping distances.Yet another factor exacerbating the traffic fatality trend in poor countries is the shortage—and often the absence altogether—of emergency medical response. Charles N. Mock, a surgeon and epidemiologist at the University of Washington’s Harborview Injury Prevention and Research Center in Seattle, has spent time in Ghana and has worked with groups in Mexico, Vietnam, and India to improve systems of emergency medical care in those nations. He points out that while organizations such as Doctors Without Borders and the International Committee of the Red Cross can provide physicians on episodic bases, such as in response to earthquakes and wars, there really isn’t an available pool of doctors that poor countries can call upon to provide sustained improvement of emergency medical response.Mock admits that the situation may sound dismal, at least at the moment. “But to sit back and say nothing can be done because of the economic problems isn’t fruitful,” he says. “A tremendous amount can be accomplished. Mortality rates can be decreased, medically preventable death can be prevented, disabilities can be prevented, and part of the discrepancies in outcome between rich and poor countries can be eliminated by improving organization and planning for trauma care services without necessarily spending very much more.”Mock has been intimately involved in a project, cosponsored by the WHO and the International Society of Surgery, to formulate a low-cost model that nearly every country can implement to greatly improve emergency trauma care. The model identifies specific essential elements that are necessary for trauma care—human resources, equipment, supplies—for purposes of aiding countries in performing needs assessments. Mock has spent this year at WHO headquarters in Geneva working on the plan’s implementation.Other organizations are embarking on other programs. In 1999, the World Bank created an organization called the Global Road Safety Partnership (GRSP), an international collaboration between business, civil society, and government organizations to improve road safety conditions around the world. GRSP is currently involved in a variety of projects in 10 countries. For example, in Bangalore, India, GRSP has created partnerships to launch an anti–drunk driving campaign and to improve roadways in high-traffic areas to enhance safety. In addition, the CDC has been working with the ministries of health and other groups in Mexico, Colombia, and El Salvador to devise creative new ways to reduce injuries to pedestrians, bicyclists, and motor vehicle occupants. And the World Bank is providing $25 million for the Vietnam Road Safety Project with a goal of achieving continuous, long-term reduction of traffic crashes in that country.Sleet also points to other local strategies in place that reduce the likelihood of crashes. Some cities are pursuing better land use management for optimized traffic flow, and promoting alternative transportation modes such as mass transit. Other strategies target drunk driving and speeding behaviors, and promote the use of cycle helmets, seat belts, and other protective devices. Still others seek to separate non-motorized traffic (such as pedestrians and cyclists) from motorized traffic.World Report. In the United States, for instance, the will to do something about the nation’s ever-growing highway death tolls began in the 1960s. Ralph Nader’s 1965 book Unsafe at Any Speed detailed the minimal attention being paid to safety in the auto industry, and the next year President Lyndon Johnson signed two bills to create stricter safety standards in cars and roadways. The combination of safer cars and roadways coupled with successful efforts to promote safer behaviors (such as use of seat belts and “designated drivers”) has been credited with bringing about ever-diminishing rates of traffic death and injury on U.S. roadways.While these efforts are noteworthy, reducing the epidemic of traffic deaths and injuries around the globe will be impossible unless countries adopt the political will to do so on their own, states the While the United States and other developed nations possess the resources to invest in safer cars, better roadways, and improved emergency medical response, an obvious question is, how can poorer countries achieve improvements as well? According to Sleet and others who are knowledgeable about traffic safety, the answer is by adopting and adapting effective strategies, and by developing local evidence-based solutions.Injury Control and Safety Promotion by a team led by Deysi Yasmin Rodríguez, an engineer with the Research Program on Traffic and Transport at the National University of Colombia. By 2002, the nation’s traffic deaths had dropped to 6,063.In Colombia, for instance, a concerted effort to reduce traffic deaths in Bogotá and other cities has proven to be extremely successful. In 1995, Colombia first required that all vehicle owners must be insured and then instituted a 3% levy on all vehicle insurance policies, earmarking that money for a “road accident prevention fund.” Colombia had recorded its all-time record high for traffic fatalities—7,874—in 1995, according to a report in the March–June 2003 issue of In Bogotá, the nation’s capital and biggest city with 7 million inhabitants, a series of mayors have instituted several programs to reduce traffic deaths and injury, such as closing bars at 1 a.m. instead of 3 a.m. and urging people to drink in moderation if they’re driving, reducing the number of cars during rush hour by encouraging workers to find alternative means of transportation (such as carpooling), and reclaiming sidewalks for pedestrians by prohibiting the old practice of allowing drivers to park their cars there. The outcome has been striking: the number of traffic fatalities in Bogotá declined from 1,387 in 1995 to 697 in 2002.According to Rodríguez, the national Ministry of Transport is now finishing plans to broaden the Bogotá approach to the entire nation. “Among the main strategies we have is the generation of a new culture about road safety in the country,” says Rodríguez, who is a consultant on the project.Still, even though Colombia has made great progress, Rodríguez sees distinct obstacles ahead. There are “few economic and human resources capable of supporting the programs in a continuous way,” she says.The WHO/World Bank report includes a series of recommendations to reduce global traffic deaths and injuries. It strongly advocates the identification of a lead agency in every nation to be in charge of traffic safety. It then recommends the routine collection of traffic crash and injury data to document the magnitude of the problem and the key risk factors. It goes on to recommend the formulation of a national plan of action in every country, together with implementation of the plan using science-based interventions.But as Rosenberg emphasizes, there are serious impediments to the creation of good traffic safety plans in poor countries. “We say, ‘Form a coordinating agency in your country,’ but we’ve got to get them the resources to do it,” he says. “Each step takes money, and right now they don’t have the resources.”To Rosenberg, the problem is akin to where AIDS/HIV stood 20 years ago. “We tended to the problem just within our own borders and completely ignored what was happening in sub-Saharan Africa until it was too late. We need to learn from that epidemic and apply it to this one, because with this one we have a chance to prevent it,” he says. “When AIDS came twenty years ago there were no good means to prevent it or treat it, and not even a good test to diagnose it. But with traffic safety there are many very clear and effective things we can do. If we let this one get out of control, we will have no excuse. We will have failed in our responsibility to become good ancestors.”


Endocrinology now present an intricate picture of how estradiol, the body’s primary endogenous estrogen, acts in the cerebellum, with one study building on the other and including another layer of complexity: the addition of the xenoestrogen bisphenol A to the system.Estrogens are known to trigger rapid cellular responses, including hormone secretion and cell permeability changes, in tissues as diverse as the pancreas, the pituitary gland, and the brain. Two studies published in the December 2005 issue of in vitro, identified the individual steps in a cascade of cellular responses triggered by estradiol. The second study focused on this response following injection of estradiol and bisphenol A, alone and in combination, into rat cerebella. Effects were seen at very low doses of 10−12 to 10−10 moles per liter (M) and at higher doses of 10−7 to 10−6 M, but not at intermediate doses of 10−9 to 10−8 M. Paradoxically, when bisphenol A was injected alone, it mimicked estradiol; when injected with estradiol, however, it blocked estradiol action.The studies, conducted by researchers led by Scott Belcher at the University of Cincinnati College of Medicine, investigated an estrogen-mediated extracellular signal–regulated kinase system in developing rat cerebella neurons. The first study, conducted Endocrinology papers, bisphenol A exerts an effect through a complex system at a concentration range that has not been evaluated in traditional risk assessment.Bisphenol A is a known endocrine-active chemical. Low-level human exposure is widespread due to the chemical’s presence in polycarbonate plastic and epoxy resins, but understanding long-term consequences of exposure will be challenging. As illustrated in the “It is a fundamental part of endocrinology, and it is beautifully demonstrated [in these papers], that stimulation at [the cerebellar] cell surface receptor is able to cause effects at doses below a part per trillion,” says Frederick vom Saal, a professor of biology at the University of Missouri–Columbia. Not only are the doses many magnitudes lower than those considered in classic high-dose toxicity studies, but at extremely low doses both estradiol and bisphenol A demonstrate a response that disappears as the dose increases. “This absolutely challenges the fundamental assumption of risk assessment that once you start increasing dose you always see an increase in response,” says vom Saal.According to Belcher, an assistant professor of pharmacology and cell biophysics, labeling the effects observed in his group’s studies as harmful or negative is not possible. “With the way it’s been looked at, you can’t say whether the observed actions are safe or harmful, but it is clear that the issue needs to be looked at more carefully and seriously,” he says.Endocrinology papers to the sphere of risk assessment won’t be easy. “It’s not so straightforward to figure out what the results mean for human health, even if you take the results that are published at face value,” says Steve Hentges, executive director of the American Plastics Council polycarbonate business unit. “Even to develop a testable hypothesis is not very simple at all. It’s very complex systems that they’re looking at. The mechanism is a long way from any kind of an adverse effect.”Although the plastics manufacturing industry, represented by the American Plastics Council in Arlington, Virginia, generally questions several aspects of bisphenol A research, they do agree that translating findings such as those in the Belcher, too, believes that extending his work into risk assessment is premature. “You can’t make a conclusion whether bisphenol A is going to be safe or harmful with current risk assessment models at these low doses,” he says. Further, as shown by the paradoxical reaction to bisphenol A, responses to an estrogenic compound can depend on what else is in the system.


A study is published reporting that a new drug works better in black people than in whites. Is this an informative study or is it based on archaic, incorrect, even harmful notions of human difference?Homo sapiens has been called the species that names. An extensive literature reflects millennia of concern over what we humans call ourselves and others. All life sciences are now grappling further with how to categorize and study the nearly infinite polymorphisms within and among “species” as awareness grows that the species concept itself is inadequate. Human medicine, however, is in a unique position in that not only must it confront these problems of categorization that plague all life sciences, but this effort occurs in a complex sociopolitical context. As Smart and colleagues recently said, “One reason that race and ethnicity are difficult concepts to operationalize or examine in scientific research is that they have meaning and usage that exists beyond the domain of scientific control” [control” .PLoS Medicine, Braun et al. [Nature Genetics editorial that argued for inclusion of multiple types of information  so that the data can be “grouped flexibly to serve the needs of medical geneticists, epidemiologists, and biological anthropologists” [In this issue of n et al.  discuss n et al.  agree thlogists” . To complogists” ,6.With this range of opinions, lack of unity and authority, and constraining rule from the largest granting agency in the US, the debate on whether and how to use race and ethnicity in biomedical research and its reporting seems almost intractable.In journal publishing particularly, the need for clarity and guidance on how to define and use race and ethnicity is increasing, especially over the last decade or so as the numbers of studies in two specific areas increase: genetic associations and studies of health inequities . HoweverNature Genetics devoted an entire special issue (“Genetics for the Human Race”) to a discussion of how to conceptualize, define, and study human racial and genetic differences . As noted above, a few journals have added instructions or guidance to their author guidelines .What can journals do? Should designations of race and ethnicity be left to an author's discretion, since, after all, authors know the most about their own studies? Some editors have adopted such an approach, arguing that the author and referees are best equipped to offer expert guidance on the matter ,9. Otherhttp://www.icmje.org/). Over 600 journals (PLoS Medicine among them) have agreed to follow their Uniform Requirements for Manuscripts Submitted to Biomedical Journals [However helpful and forward-thinking these individual journal responses are, community consensus would be more useful and authoritative. General scientific or medical editorial style guides have added useful detail and explanations to their chapters on terminology with each new edition ,14. A weJournals . RegardiJournals ). Some aJournals ,11.http://www.ama-assn.org/), and CSE , other organizations that might help develop such international consensus include WAME  and EASE .A more detailed community consensus would provide the benefits of uniformity and legitimacy for both authors and editors. In addition to ICMJE, AMA  and theon 11.10 ) offer aWhose responsibility should it be to ensure that race, ethnicity, and other human variables are described appropriately? Authors and referees, who know their research and fields better than most journal editors do? Or editors, whose mandate it is to uphold the scientific and ethical quality of their journals? The answer is both, working collaboratively.Ideally, authors would design their studies, including the reporting of studies, to the highest standards available at the time. Because those standards keep changing, however, editors can't make authors go back in time and redesign a decades-long prospective study to meet contemporary editorial standards. Editors should insist, however, that authors of studies based on different human categories should make their methods of categorizing human populations transparent, justify their study design, and control for confounding variables. And copyeditors can help by being well informed about current trends in usage, and should query authors about what, exactly, is meant by “black” or “homosexual” or “poor” or “elderly” when these designations are not clear, and recommend changing potentially offensive labels to more acceptable terminology .The biomedical landscape is becoming rapidly more complex. Burgeoning human genome and epidemiologic data, racially defined pharmaceutical treatments, and increased public concern over scientific research ethics combine to force everyone involved to confront the problems of defining and studying the causes and consequences of human differences. It is clear that although much can be done to improve clarity of reporting, race, ethnicity, religion, sex, sexual orientation, age, disease, disability, weight, and any of the multitude of other ways of categorizing humans are here to stay.


Competitions and community exchanges are spurring scientific progress. Drosophila Genome Center at the University of California at Berkeley when, as a young PhD student, he encouraged colleagues to approach their work in an entirely new way. The goal was to develop efficient computational tools to predict individual genes from the masses of genetic code being sequenced. “The problem was people published papers on their algorithms…on different data sets,” recalls Reese, “so it was very hard to get a really good assessment on actually whose is the best and what are really the right methods and the right underlying signs to be used to do this job right.” Borrowing an idea from protein biologists, Reese brought together 12 teams under the umbrella of the Genome Annotation Assessment Project (GASP), provided them with the same Drosophila sequence to hone their prediction programs, and invited them to defend their results at a workshop in Heidelberg, Germany, a few months later, in July 1999. What the participants lacked in funding, they made up for, in abundance, with bonhomie and commitment, says Reese. And the timing could not have been better. The newly available Drosophila genome allowed Reese to test the workshop's top two programs on the front line: “We learned some tricks through this experiment [and] the Drosophila was one of the best annotated genomes as a result” , and a Rejuvenation Prize for the best late-onset intervention . Awards come from a fund, currently valued at around $1.3 million, to which anyone may contribute. A leading sponsor is “The 300”—modelled on the 300 Spartans who crucially delayed the invasion of Greece by hordes of Persians in 480 B.C.—whose members pledge regular contributions to the fund and whose names will be etched in history (as those of the Spartans were engraved on a stone tablet in Sparta).An ongoing challenge that consists of two awards: a Longevity Prize for the oldest British mathematician Alan Turing postulated, in 1950, that a “thinking” computer could produce responses to fool an interrogator that it was human; the prize, created by New Jersey industrialist Hugh Loebner in 1990, keeps the Turing Test a live challenge. Loebner has pledged $100,000  for the first computer whose responses are indistinguishable from a human's. In the meantime, an annual prize of $3,000  goes to the most human computer that year. In 2005, according to Loebner, the award of $25,000  looks likely to be won for the first time.This prize was established in 1714 by the British government to determine longitude at sea. Instead of relying on astronomical sightings, watchmaker John Harrison built a precision clock to keep the time of a home port (of known longitude). Denied the £20,000 prize by assessors (wary that astronomy had been bypassed), Harrison petitioned King George III to circumvent them and to persuade Parliament to award him directly. Harrison was finally rewarded in 1773, 12 years late and 45 years after he began work on his “marine chronometer”. He died on his birthday in 1776, at the age of 83.Just this year, NASA announced a deadline stretching into 2008 for its third Centennial Challenge competition, the Moon Regolith Oxygen Challenge, to extract breathable oxygen from simulated lunar soil, and is dangling a purse of $250,000 in front of likely duellists.Such prizes can bask in ambitious publicity campaigns and cash incentives, running into millions of dollars, in an effort to tap the broadest seam of ingenuity, yet money and marketing, even military muscle, are no guarantee of success. The Defense Advanced Research Projects Agency is having to rerun the Grand Challenge it staged late last year to find the fastest “autonomous ground vehicle” that can cover around 175 miles of treacherous desert track in under ten hours. Unperturbed, the Defense Advanced Research Projects Agency has doubled the prize money to $2 million. London Underground, which runs the capital's subterranean train service, has just abandoned its Cooling the Tube contest, after spending nearly two years appraising 3,500 entries from 60 countries and failing to find any feasible innovation to cope with summer heat waves that leave Tube travellers sweltering. And London Mayor Ken Livingstone, who promised £100,000 to the winner in 2003, has kept his hands in his pockets.Against this background, the astonishing success of GASP and of a flourishing brand of similar low-key and often low-budget exchanges among scientific researchers, each vying to devise the perfect algorithm for some knotty problem, in fields that range from protein biochemistry to information retrieval to statistical genetics, seems all the more remarkable. And yet more remarkable still about these research exchanges is the avowed disdain among participants for the term “competition” to describe what they prefer to call a “community experiment”, and their claimed satisfaction (on coming first) with fame and glory among peers rather than with any cash award.As someone who could be in the running for ageing research's M Prize, Jim Carey, a population biologist and Professor of Entomology at the University of California at Davis, explains the problem with many such contests: “It is not so much that legitimate ageing researchers do not want to be seen as actively seeking a prize, as it is that a research strategy built on the goal of winning the prize would be way too high a risk.” Carey has considered his chances though. “When I heard about [the M Prize] we were in the midst of our ovary transplant mouse studies and it crossed my mind momentarily that maybe we'd be in the running. But it had no influence on our thinking about the type of research we do; this is not what drives us. If we were to ever win this prize , it would be by default rather than by inspiration; that is, we would claim the prize (since why not?) but that would not have been the driving force.”At the community-experiment level, however, goals can be much more clearly tied to practical research agendas . Among tResearch teams make blind predictions about the structures of the same set of proteins from given sequences of amino acids. Started in 1994 and staged every two years, the experiments are coordinated by Lawrence Livermore National Laboratory in Livermore, California. For CASP6 last year, more than 200 teams from 24 countries provided over 30,000 predictions on 90 protein domains. John Moult founded CASP in response to the “clear inadequacy of the peer reviewed publication system in this area of biology [and to] new ways of doing things made possible by cheap universal electronic communication”. An associated Web-based community discussion arena, FORCASP (Forum for CASP), provides an online meeting place and an intense discussion venue for the CASP community.Research teams make blind predictions about the structures of protein–protein complexes from given structures of the individual proteins. CAPRI aims to do for macromolecular interaction, a central theme in functional genomics, what CASP has done for protein structure. Started in 2001 and staged whenever an experimentalist offers an adequate target, according to cofounder Joël Janin, CAPRI is coordinated by the European Bioinformatics Institute at Hinxton, United Kingdom. Round seven began in May. Over four years, X-ray crystallographers have provided 21 targets, including two that were cancelled.Evaluates the performances of automatic prediction servers to determine how accurately they predict protein structures without the intervention of experts , such that nonexperts could use them with confidence.Research teams analyse the same standard datasets and compare notes on the different techniques to mine microarray data. Modelled on CASP, CAMDA was founded in 2000 at Duke University Bioinformatics Shared Resource in Durham, North Carolina, and has staged conferences every year since then.Founded in 1992 by the National Institute of Standards and Technology and the US Department of Defense, TREC is a series of workshops (TREC 2005 reports in November) to encourage research in information retrieval from large text collections, notably for the benefit of the intelligence community. A more recent initiative, supported by the US National Science Foundation, focuses on the study of the retrieval of genomic data, which is broadly interpreted to mean not just gene sequences but also supporting documentation such as research papers and laboratory reports.BioCreAtIvE—Critical Assessment of Information Extraction Systems in BiologyEstablished in 2003 at the National Center of Biotechnology  in Madrid, Spain, BioCreAtIvE claims to be the “first very biologically motivated evaluation of text mining systems”  inside my research group…I'd have been convinced that we must have cheated somehow,” he recalls. “Several predictions were much more accurate than any predictions of anything in structural biology have ever been” .Like Reese with respect to genetics, Baker sees the evolution of community experiments, in the form of CASP and CAPRI, as rescuing structural biologists from primary research papers that cannot be trusted. Too many published models rely on known results: “It's like trying to predict yesterday's weather from conditions that you knew the day before,” he says. “It's not conscious cheating, it's just that if you're trying to reproduce some set of [known] results with a computational model, if you try hard enough and you're smart enough then you'll figure out a way to do it.” The issue, he adds, is “whether you actually have captured some essential truth about how things work or whether you've just managed to twiddle all the numbers so that you reproduce a certain set of results.”He's now convinced that the days of depending on experimentation alone to determine protein biochemistry are numbered, as the benefits of CASP and CAPRI kick in: “And a good measure of when we are there is these types of experiments.” In a manuscript in review, Baker reports that “for about a third of the small proteins we looked at—very small proteins, less than 85 amino acids—we could predict their structures quite accurately. You'd like it to be 100%…but it's a lot better than it was a few years ago when it'd have been zero.” For the moment, he says, lack of sufficient computational power is the problem.John Moult, who founded CASP, agrees that reliable prediction is not far off. “I always say five years. Been saying that for about 20 years now,” he notes. “Seriously—if we can get effective refinement methods, then homology models based on high sequence identity  could quickly become competitive with experiment. However, we are only just beginning to progress on that problem, so it is hard to call.”CASP is succeeding where similar collaborations to resolve other biological questions could easily struggle, notes Moult, Professor of Computational Biology at the Center for Advanced Research in Biotechnology at the University of Maryland Biotechnology Institute in Rockville. “The CASP model requires new experimental data to become available on an appropriate time scale [and] that's fairly uncommon,” he says. “On the other hand, it is my strong conviction that new communication methods will allow a whole range of new ways of collaborating on a community scale.”But the collaboration is not always an easygoing affair. “Overall it works well, but there can of course be tensions in various forms,” says Moult. Participants who feel that the evaluation criteria are unfair to their predictions present the most common complaint: “Though this has happened, it is the exception,” he stresses. And growing sensitivity at funding agencies about the value of community experiments increases the tension. Involvement in CASP improves a researcher's chances of securing a grant, “or rather, not being involved in CASP may damage prospects,” says Moult. “This is not a good thing. It puts pressure on people to participate whether they think it's a good idea or not. I also suspect the significance of the results is sometimes overestimated by review committees.”Such friction may be more of an issue in the US than in Europe, according to Joël Janin, Professor of Biophysics at the Centre National de la Recherche Scientifique Laboratory of Structural Enzymology and Biochemistry near Paris, France, and CAPRI's cofounder. “CAPRI wasn't planned to be a competition, and I do my best to keep the 'community-wide experiment' spirit in it,” he notes. “This seems to work in Europe and Asia for the moment, but American participants tell me they feel pressure from grant agencies.” The National Institutes of Health funds CASP, while CAPRI runs on a shoestring. “When Shoshana Wodak [from the Free University of Brussels] and I launched CAPRI, there was skepticism from our colleagues in the US that it could be run from Europe,” recalls Janin. “That skepticism was partly justified—we failed to get EU funding, and in the end Shoshana is moving from Brussels to Toronto.”On the edge of these life sciences communities, looking in, is Ellen Voorhees, a computer scientist, who runs the Text Retrieval Conference (TREC) at the National Institute of Standards and Technology in Gaithersburg, Maryland, US. Since 2003, a decade after it was established, TREC has expanded its annual research workshops on improving the effectiveness of information retrieval systems, notably for the benefit of the intelligence community, to include assessments of methods for recovering genomics data.Voorhees appreciates the tensions with community experiments. While TREC assessors do evaluate different retrieval systems and publish scores, she says, “TREC offers no award, and names no winners.” But some people still call TREC a competition, and there is an undeniable competitive element to it, she admits. “I used to try to correct people who called TREC a competition, but have given that up as a hopeless task.”Voorhees appreciates the rewards of community experiments. “TREC has created a series of retrieval test collections that define benchmark tasks that drive the research. These collections simply could not have been built without a collaborative effort because the collections depend on the pooled results of many different retrieval systems. A single organisation trying to build a collection of similar size could not obtain a collection of equivalent quality because of the bias introduced by a single system.“Retrieval effectiveness doubled on the basic ‘ad hoc’ task over the first six years of TREC,” notes Voorhees. “TREC introduced the first large-scale evaluations of cross-language retrieval, and retrieval of recordings of speech. More than 250 groups from more than 20 countries have participated in at least one TREC. Many groups have participated multiple times. These groups must see some value in participating.”http://www.doe-mbi.ucla.edu/TB/], where he manages target and results lists, and in principle, anyone can do the needed experimental work.” But for Reese, who now runs Omicia, a prognostic genetics start-up he founded in 2002 in Emeryville, California, community experiments have a finite life. “Once we have all the genes found, then [GASP] will become redundant.”With community experiments proving to be such a valuable tool across computational research, could they also help to solve questions other than algorithmic ones? Baker is far from convinced: “Prediction experiments are special for prediction problems, which will generally be computational.” Janin agrees: “I cannot imagine how to organize a wet bench experiment in the same way, but who knows?” Moult is more accommodating: “Things like CASP have so far focussed on testing how well computational methods succeed at reproducing experimental reality. In that mode, [it is] hard to see how experiment might fit in,” he says, adding wryly, “experiment reproducing experiment?” But the next generation of community experiments could see more of an overlap with experiment, he concedes: “For example, asking the small molecule docking community to contribute suggestions as to what might be the ligand binding specificity of proteins of unknown function. These suggestions would then help guide experimental binding studies. This sort of community-wide computational experiment does have more similarity with some community-based experimental projects, for example, Tom Terwilliger's TB structure consortium [


Getting back to work is important for most patients but doctors are often unsure how best to help. The article reviews evidence for the effectiveness of the interventions now available. However, patients with chronic diseases often encounter difficulties upon returning to work after an episode of illness . Helpingissues” . I wouldThere is a wide range of disability among patients, even when they have had the same disease with equal severity. For example, among patients who have survived breast cancer after surgery and chemotherapy, sick leave is on average about a year, but it nevertheless varies from a couple of days to a couple of years. Among patients with testicular cancer who have undergone surgery, there is a variation of several weeks in the duration of sick leave . For patThe model offers three opportunities for intervention. The first opportunity is better treatment. In the 1970s and 1980s, a change in the treatment of heart disease greatly influenced its related disability . SecondlThe WHO International Classification of Functioning model is supported by many studies that have investigated the prognosis for return to work among patients suffering from a variety of diseases. From these studies, it can be concluded that the severity of the disease resulting in impairment of body function or structure usually has the biggest influence on the time needed to return to work, but environmental factors and person-related factors play an additional role . LookingSeveral theories explain the mechanisms of how the person-related factors mentioned in the WHO International Classification of Functioning model are important in predicting return to work. First, there is the well-known “theory of illness behaviour”, elaborated by David Mechanic, which states that people interpret bodily symptoms differently and as a consequence will behave differently . It explHow our ideas about illness influence our way of coping with disease has been elaborated by E. A. Leventhal in the “model of illness representations”. The model, or theory, states that if the patient considers the disease as a narrowly defined medical disorder, the duration as long and the consequences as serious, the functional outcome will be worse, irrespective of the objective medical seriousness of the illness . These iTo find evaluations of return-to-work interventions, I searched Medline through PubMed with the search strategy recommended by Haafkens et al., i.e., combining the following text words with “or”: “return to work”, “returned to work”, “sick leave”, “sickness absence”, “work capacity”, “work disability”, “vocational rehabilitation”, absenteeism, retirement, “employment status”, and “work status”. I restricted the search to randomised controlled trials (RCTs), and to find psychological treatment, I added “psychol*” or “cognitive”. This yielded 225 studies. Of these, I found the following studies relevant.For four major disease categories— heart disease, rheumatoid arthritis, back pain, and common mental health disorders—studies have been conducted to determine if these prognostic factors are amenable to change .In an RCT among hospital patients with myocardial infarction, perception of the illness was changed by a brief psychological intervention leading to a twice-as-fast rate of return to work . The intFor nonspecific lower back pain, Gordon Waddell was one of the first to recognise the importance of a patient's beliefs about the disease and the social interactions between patients and the environment . AccordiLastly, patients with common mental health problems such as adjustment disorder, depression, anxiety, or somatisation problems are especially prone to long-term disability. Two cluster-randomised trials showed that sick leave can be reduced substantially among patients with common mental disorders. In one, a cognitive-behavioural approach of workers with adjustment disorder improved the rate of return to work in comparison with standard care . The othA recent Cochrane review of psychological interventions carried out by general practitioners concluded that individual clinicians are able to incorporate such interventions into their treatment . For exaThe implication of these studies for clinical practice is firstly that all doctors should ask patients if they work and if they have reported sick. Possible hindrances for return to work such as a failure to make special arrangements in the workplace or misconceptions of disability should be explored. These issues can subsequently be addressed by referring patients to an occupational health professional or by using the cognitive-behavioural techniques mentioned above. To facilitate the implementation of these measures in practice, clinical guidelines should include guidance on return-to-work interventions.


Lung cancer kills more Americans each year than all leukemias and cancers of the breast, prostate, and ovary combined. But a new diagnostic that may allow early detection of the dominant form of the disease could change that grim picture. A team of researchers at the University of Kentucky Chandler Medical Center in Lexington led by Li Zhong, an assistant professor in the Division of Pulmonary, Critical Care, and Sleep Medicine, has developed a blood test for detecting non–small cell lung cancer (NSCLC), the disease associated with 80% of diagnosed lung cancers.An estimated 175,000 new cases of lung cancer will be diagnosed in 2006, according to the American Cancer Society, and about 162,000 people will die of the disease. Fewer people are dying of NSCLC than in the past, which may reflect fewer people smoking. Still, those diagnosed tend to be diagnosed late, and those diagnosed late tend to die of the disease.Spiral computed tomography (CT) imaging is today’s gold standard for lung cancer detection, able to identify tumors less than 1 cm in diameter. But at more than $400 a test, spiral CT imaging is far too costly for population-level screening. Further, there is growing concern that spiral CT imaging is overdetecting lung cancers that, left alone, would not progress, and might even regress. A better test would be one specific for cancers that are actively progressing.Journal of Thoracic Oncology, uses a panel of five cancer-associated protein markers identified by their reactivity to antibodies in cancer patients’ blood. The markers were identified by generating a panel of proteins corresponding to genes expressed in NSCLC cells, then probing them with antibodies from NSCLC patients’ blood. The five proteins that were the most discriminating—reacting to antibodies from patients much more than they reacted to antibodies found in the blood of nonpatients—were tested together for their ability to discern between blood samples drawn from diagnosed NSCLC patients and those from nonpatient controls.Zhong’s test, described in the July 2006 issue of the Used together, the five markers form a “fingerprint” for cancerous samples, with a readout that is highly specific, able to separate cancer and noncancer samples in 87.5% of cases tested. By comparison, the widely hailed prostate-specific antigen test for diagnosing prostate cancer is just 36% accurate, and the CA125 test for ovarian cancer is 57% accurate. The new test can also recognize cancerous samples in earlier stages.The cost of the new test will depend on the diagnostic platform ultimately developed, but is expected to be significantly less than the current standard. “We can lower the risk of people [progressing] to advanced-stage lung cancer,” Zhong says. “If you can screen less expensively first, then you can suggest some people for follow-up—come back in six months and redo the test, or for some, go ahead and take the CT test now.”Jonathan Cohen, whose Rockville, Maryland, company 20/20 GeneSystems is developing the new test toward clinical application, is confident that the test could change outcomes. “A lot of diagnostic products stumble because they won’t make a clear clinical impact,” he says. “This is one where there’s a significant unmet need and a clear and very compelling clinical utility.”Ruth Etzioni, a cancer statistician at the Fred Hutchinson Cancer Research Center in Seattle, recommends caution, though. Of this and the other new fingerprint diagnostics coming into use, she says, “The sensitivity and the ability to identify tumors is only the first step. Then whether it actually carries with it a significant benefit and a low harm profile is the key.”