Some articles....
Apr. 17th, 2007 12:42 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
conuly
Almost Human, and Sometimes Smarter
By JOHN NOBLE WILFORD
CHICAGO — Observed in the wild and tested in captivity, chimpanzees invite comparison with humans, their close relatives. They bear a family resemblance that fascinates people, and scientists see increasing evidence of similarities in chimp behavior and skills, making some of them think on the vagaries of evolution.
For some time, paleontologists and evolutionary biologists have known that chimp ancestors were the last line of today’s apes to diverge from the branch that led to humans, probably six million, maybe four million years ago. More recent examination shows that despite profound differences in the two species, just a 1.23 percent difference in their genes separates Homo sapiens from chimpanzees, Pan troglodytes.
And certain similarities between the two species, scientists say, go beyond expressive faces and opposable thumbs.
Chimps display a remarkable range of behavior and talent. They make and use simple tools, hunt in groups and engage in aggressive, violent acts. They are social creatures that appear to be capable of empathy, altruism, self-awareness, cooperation in problem solving and learning through example and experience. Chimps even outperform humans in some memory tasks.
“Fifty years ago, we knew next to nothing about chimpanzees,” said Andrew Whiten, an evolutionary psychologist at the University of St. Andrews in Scotland. “You could not have predicted the richness and complexity of chimp culture that we know now.”
Jane Goodall, a young English woman working in Africa in the 1960s, began changing perceptions. At first, experts disputed her reports of chimps’ using tools and social behavior. The experts especially objected to her references to chimp culture. Just humans, they insisted, had “culture.”
“Jane suffered early rejection by the establishment,” Richard Wrangham, a Harvard anthropologist, said. “Now, the people who say chimpanzees don’t have emotions and culture are the ones rejected.”
The new consensus framed discussions in March at a symposium, “The Mind of the Chimpanzee,” at the Lincoln Park Zoo here. More than 300 primatologists and other scientists reviewed accumulating knowledge of chimps’ cognitive abilities.
After one session, Frans de Waal of Emory University said that as recently as a decade ago there was still no firm consensus on many of the social relationships of chimps. “You don’t hear any debate now,” he said.
In his own studies at the Yerkes Primate Research Center at Emory, Dr. de Waal found that chimps as social animals have had to constrain and alter their behavior in various ways, as have humans. It is a part of ape inheritance, he said, and in the case of humans, the basis for morality. The provocative interpretation was advanced in his recent book, “Primates and Philosophers.”
Other reports shortly before the symposium had elaborated on the abilities of chimps as toolmakers. Jill Pruetz, a primatologist at Iowa State University, described 22 examples of chimps in Senegal making stick spears to hunt smaller primates for their meat. Dr. Goodall was the first to call attention to chimps as hunting carnivores, not strictly vegetarians.
Dr. Pruetz observed several chimps jabbing the spears into hollow tree trunks where bush babies often dwell. Just one attempt was successful. Previously, chimps had been seen using sticks mainly to extract termites from their nests.
A team of archaeologists led by Julio Mercader of the University of Calgary reported finding stones in Ivory Coast that chimps used 4,300 years ago to crack nuts. Today’s chimps have often been videotaped using rocks as a hammer to open nuts. The old stones with starch residues from nuts, the researchers said, were the earliest strong evidence of chimp tool use, and the finding suggested that chimps had learned the skill on their own, rather than copying humans.
Other researchers combine field work showing chimp behavior in natural habitats with laboratory experiments that are created to disclose their underlying intelligence — what scientists call their “cognitive reserve.”
For example, chimps on their own would not sit at a computer responding with rapid touches on the screen as a test of their immediate memory. Videos of their doing just that at Kyoto University in Japan especially impressed the symposium scientists.
Tetsuro Matsuzawa, a Kyoto primatologist, described a young chimp watching as numbers 1 through 9 flashed on the computer screen at random positions. Then the numbers disappeared in no more than a second. White squares remained where the numbers had been. The chimp casually but swiftly pressed the squares, calling back the numbers in ascending order — 1, 2, 3, etc.
The test was repeated several times, with the numbers and squares in different places. The chimp, which had months of training accompanied by promised food rewards, almost never failed to remember where the numbers had been. The video included scenes of a human failing the test, seldom recalling more than one or two numbers, if any.
“Humans can’t do it,” Dr. Matsuzawa said. “Chimpanzees are superior to humans in this task.”
Dr. Matsuzawa suggested that early human species “lost the immediate memory and, in return, learned symbolization, the language skills.”
“I call this the trade-off theory,” he continued. “If you want a capability like better immediate memory, you have to lose some other capability.”
Other experiments at Kyoto’s primate center demonstrated the ability of chimps to recognize themselves and focus attention on others. Masaki Tomonaga, who conducted the tests, said that an infant made eye with its mother at about 2 months and that sometime after the first year was able to maintain a gaze as the mother moved about.
Dr. Tomonaga said such “gaze following” developed in humans about the same age, “though infant humans generally have more complex interactions.”
Misato Hayashi, also from Kyoto, described experiments with infant chimps’ manipulating nesting cups and square and cylindrical blocks. They were slower to learn than humans, but the manual dexterity was there. A human starts stacking blocks shortly after age 1, he said; chimps are almost 3 before getting the hang of it.
In experiments with mirrors, researchers showed that chimps had an awareness of themselves that is absent in monkeys but present in dolphins and all the great apes. Similar tests by Emory scientists showed some self-recognition among elephants.
These behaviors were reported by Dr. de Waal and his associate J. M. Plotnik, who said that they “may suggest convergent cognitive evolution probably related to complex sociality and cooperation well documented in both chimpanzees and elephants.”
Other researchers said that when confronted with problems obtaining food from the other side of a fence, chimps were not only clever on their own and often competitive with a fellow chimp, but they also showed a willingness to cooperate with one another to get the job done.
Brian Hare of Duke University and the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, said bonobos outperformed their chimp relatives in cooperative tasks and shared food more readily.
The emotions of caring and mourning have been observed, as in the case of the chimp mother that carried on her back the corpse of her 2-year-old daughter for days after she had died. After fights between two chimps, scientists said, others in the group were seen consoling the loser and acting as mediators to restore peace.
Devyn Carter of Emory described the sympathetic response to a chimp named Knuckles, who was afflicted with cerebral palsy. No fellow chimp was seen to take advantage of his disability. Even the alpha male gently groomed Knuckles.
Dr. Wrangham of Harvard said the challenge to primatologists working in the field was to learn how much of the behavior and “surplus cognitive capacity” observed in captivity applied in the wild.
The answer seems to vary from one isolated chimp community to another. Scientists said that indicated the role of social learning — picking up skills by emulation — and responses to different opportunities in separate cultures.
At Gombe, the site in Tanzania where Dr. Goodall made a name for herself, the chimps with stick tools are accomplished extractors of termites from their nests. But termite fishing is rare in Bossou, Guinea. At Bossou, and not Gombe, chimps have learned to make use of many other tools, including stones for cracking nuts.
Dora Biro of the University of Oxford in England has studied tool use by chimps at the Bossou site. They fold leaves in a mat to sponge water out of tree hollows and scoop algae off stream surfaces. They collect edible ants with sticks. They take stouter tree branches and pound the juicy palm fiber to a pulp, preparing another favorite food.
Videos of Bossou nutcrackers show adult chimps, often female, placing a nut on a flat stone anvil and slamming down on it with a smaller rock. Two or three youngsters sit around watching. The adults do not appear to be giving instructions, except by example.
“What we’ve learned is that manipulation of objects begins around 1 year of age,” Dr. Biro said. “If it involves two or three objects, as in cracking nuts, that happens at 3 ½ to 5 years. If it is not learned by 6 or 7, it will never be acquired.”
At a dense forest in the Congo Republic, Crickette M. Sanz of the Max Planck institute said the chimps seemed as curious about her as she was about them. Groups came forward, calling others to join them. Sometimes, they sat with her for hours, eating fruit, grooming and even mating.
For a more detached study, Dr. Sanz deployed 18 video cameras at remote locations and recorded 84 hours of chimp tool use. Leaf sponging was the simplest, she concluded, and collecting honey with a long stick required the most effort and risk, with termite fishing having “the highest element of success.”
Dr. Sanz, who has worked with her husband, David B. Morgan, on some of the research, described mother chimps’ carefully withdrawing from a hole sticks swarming with black termites while their infants looked on. These social interactions, she said, passed on essential techniques and behaviors to the next generation.
“Socially transmitted adjustable behavior,” Dr. de Waal said, is a hallmark of culture.
Chimp behavior sometimes turns violent, particularly in territorial clashes. In Uganda, John Mitani of the University of Michigan observed chimp patrols regularly policing the forest boundaries of their communities. One patrol was seen assaulting an adult male, killing and emasculating him.
Kristin Bonnie, another Emory primatologist, said the transmission of behavior could be benign and spontaneous, with the prospect of reward being secondary. “It is the desire to act like others, an identification with certain others,” she explained, citing as an example the way chimps usually clasp hands while grooming each other.
At the symposium, researchers said the interest in learning more about chimps was not just a case of knowledge for the sake of knowledge. Their behavior and intelligence, scientists say, may offer insights into the abilities of early human ancestors like Australopithecus afarensis, the apelike “Lucy” species that thrived more than three million years ago. A more urgent motivation for the research, primatologists say, is that these are sentient beings and the closest living relatives of humans, and their survival is threatened.
Elizabeth V. Lonsdorf, a primatologist at the Lincoln Park Zoo and a symposium organizer, said researchers needed “to keep their eyes out for ways to improve the care of chimpanzees.”
Diseases like ebola and anthrax are taking their toll. Hunting chimps for “bush meat” is increasing. Many of the forest habitats of chimps in central Africa are being cut by loggers and land developers. As a result, Dr. Lonsdorf said, “Groups of the animals are getting closer together, which increased the threat of chimp violence and territorial disputes.”
Dr. Goodall recalled that when she went to Africa nearly a half-century ago, at least a million chimps lived in the continent, and “now there are perhaps only 150,000.” In that time, they have impressed scientists with physical and emotional reminders of their kinship to humans and their occasional triumphs over them at a computer screen.
On the Spanish Flu, and how intervention saved lives
How (and How Not) to Battle Flu: A Tale of 23 Cities
By NICHOLAS BAKALAR
When the Spanish flu reached the United States in the summer of 1918, it seemed to confine itself to military camps. But when it arrived in Philadelphia in September, it struck with a vengeance.
By the time officials there grasped the threat of the virus, it was too late. The disease was rampaging through the population, partly because the city had allowed large public gatherings, including a citywide parade in support of a World War I loan drive, to go on as planned. In four months, more than 12,000 Philadelphians died, an excess death rate of 719 people for every 100,000 inhabitants.
The story was quite different in St. Louis. Two weeks before Philadelphia officials began to react, doctors in St. Louis persuaded the city to require that influenza cases be registered with the health department. And two days after the first civilian cases, police officers helped the department enforce a shutdown of schools, churches and other gathering places. Infected people were quarantined in their homes.
Excess deaths in St. Louis were 347 per 100,000 people, less than half the rate in Philadelphia. Early action appeared to have saved thousands of lives.
Scientists are still studying the 1918 pandemic, the deadliest of the 20th century, looking for lessons for future outbreaks — including the possibility that H5N1, the avian influenza virus, could mutate into a form spread easily from human to human. This month, researchers published two new studies in The Proceedings of the National Academy of Sciences comparing public-health responses in cities like St. Louis and Philadelphia.
Using mathematical models, they reported that such large differences in death rates could be explained by the ways the cities carried out prevention measures, especially in their timing. Cities that instituted quarantine, school closings, bans on public gatherings and other such procedures early in the epidemic had peak death rates 30 percent to 50 percent lower than those that did not.
“It had been received wisdom that these interventions didn’t work,” said Dr. Richard Hatchett, the lead author of one of the studies, “because they looked at the variability between cities and concluded that there was some other factor than the interventions that caused the differing outcomes.
“That we were able to go back and ask the right questions,” Dr. Hatchett said, “is a function of a lot of modeling work that we did previously.”
Dr. Hatchett, who is a researcher at the National Institutes of Health, said the findings might hold lessons for the 21st century. “When multiple interventions were introduced early, they were very effective in 1918,” he said, “and that certainly offers hope that they would be similarly useful in an epidemic today if we didn’t have an effective vaccine.”
A two-week difference in response times, according to the researchers, is long enough for the number of people infected in an influenza epidemic to double three to five times.
Dr. Martin Cetron, director for global migration and quarantine at the federal Centers for Disease Control and Prevention in Atlanta, found reason for optimism in the study results.
“The thing I find encouraging about the Hatchett paper,” he said, “is that when you look back to 1918, you find that those who used nonpharmaceutical measures effectively were able to mitigate the impact of the severe pandemics, and this is consistent with some of the 21st-century simulation models.”
The second study, in the same issue of The Proceedings, suggests that in one sense preventive measures can be too effective. In an influenza epidemic, a certain number of people survive the illness and are immune to reinfection. As these numbers increase, the epidemic fades.
But an effective prevention program without a vaccine can leave enough people uninfected and still susceptible to the virus to start the epidemic again as soon as the controls are lifted. This is what happened in St. Louis. On Nov. 14, 1918 — in high spirits three days after the armistice that ended the war, and with influenza cases declining — the city reopened schools and businesses. Two weeks later, the second wave of the epidemic struck, this time with children making up 30 percent to 40 percent of the infections. Controls were immediately reinstituted.
The study examined the course of the epidemic in 23 cities: San Francisco, St. Louis, Milwaukee and Kansas City, Mo., had the most effective prevention programs, and time was of the essence. If restrictions were introduced too late or lifted too early, success rates declined substantially.
Neil Ferguson, a co-author of the second study and a professor of epidemiology at Imperial College London, explained in a telephone interview that the most successful interventions were in communities where the political and health authorities broadly agreed on what needed to be done and got significant cooperation from the public.
The key, Dr. Ferguson said, is to tune an imperfect intervention perfectly so that a single peak of minimal size is the result. Although no cities succeeded in doing this, those that got closest, like St. Louis, carried out early interventions before the first peak, and then reinstituted them when transmission rates began to rise again.
What these results mean for a future epidemic is not clear. “If avian flu became a pandemic tomorrow,” Dr. Ferguson said, “we would start a crash program to make a vaccine.”
But he added that rigid preventive measures like quarantines, mandated mask wearing and widespread business closings would still need to be put in place.
“What our study shows,” he continued, “is that interventions even without a vaccine can be effective in blocking transmission. What’s much less certain is whether society is prepared to bear the costs of implementing such intrusive and costly measures for the months that would be required to manufacture a vaccine.”
For Some Hispanics, Coming to America Also Means Abandoning Religion
For Some Hispanics, Coming to America Also Means Abandoning Religion
By LAURIE GOODSTEIN
RICHMOND, Va. — On Sunday afternoons, when the local Roman Catholic church holds Mass for Spanish-speaking Catholics, Edgar Chilín is playing soccer in a league with hundreds of Hispanic players.
As a child in Guatemala, Mr. Chilín attended Mass every Sunday. But after immigrating to the United States 25 years ago, he and his family lost the churchgoing habit. “We pray to God when we feel the need to,” he said, “but when we come here to America we don’t feel the need.”
A wave of research shows that increasing percentages of Hispanics are abandoning church, suggesting to researchers that along with assimilation comes a measure of secularization.
Several studies show that Hispanics are just as likely as other Americans to identify themselves as having “no religion,” and to not affiliate with a church. Those who describe themselves as secular are, without question, a small minority among Hispanics — as they are among Americans at large. But, in contrast to many of the non-Hispanic Americans who identify themselves as secular, most of the Hispanics say they were once religious.
The Roman Catholic Church, the religious home for most Hispanics, is experiencing the greatest exodus. While many former Catholics join evangelical or Pentecostal churches, the recent research shows that many of them leave church altogether.
“Migrating to the U.S. means you have the freedom to create your own identity,” said Keo Cavalcanti, a sociologist at James Madison University in Harrisonburg, Va., and a co-author of a recent study that found a trend toward secularization among Hispanics in Richmond. “When people get here they realize that maintaining that pro forma display of religiosity is not essential to doing well.”
A separate study of 4,000 Hispanics to be released this month by the Pew Forum on Religion and Public Life and the Pew Hispanic Center found that 8 percent of them said they had “no religion” — similar to the 11 percent in the general public. Of the Hispanics who claimed no religion, two-thirds said they had once been religious. Thirty-nine percent of the Hispanics who said they had no religion were former Catholics.
Hispanics from Cuba were the most secular national group, at 14 percent, followed by Central Americans at 12 percent, Puerto Ricans and Dominicans at 9 percent, and South Americans at 8 percent, the Pew poll found. Mexicans in this country were the least likely to say they had no religion, at 7 percent.
A larger survey, called the American Religious Identification Survey, a study of 50,000 adults, including 3,000 Hispanics, found that the percentage of Hispanics who identified themselves as having no religion more than doubled from 1990 to 2001, to 13 percent from 6 percent.
This change is happening even though many Hispanics immigrated from countries steeped in religion, where saints’ days and festivals mark the passage of time, and grandmothers round up their progeny each Sunday to go to Mass.
“They come, they adopt the American way, and part of the American way is moving towards no religion,” said Ariela Keysar, associate director of the Institute for the Study of Secularism in Society and Culture at Trinity College in Hartford.
Each year, Diana Lemus — a real estate agent and owner of Happy Mart, a busy Latino market in Richmond — makes New Year’s resolutions that include working out more, getting out of debt, being a better mother and attending church once a week.
Ms. Lemus, a first-generation immigrant, said that this year she had kept all of them, except going to church — and spends Sunday mornings at the gym. She thinks her faith is important, but said that perhaps she has grown “too materialistic.”
“I need God in my life, but I told the pastor, I get sleepy,” she said. “You have to stay in church from 1:30 to 5. I think if services were shorter, more entertaining.”
Like Ms. Lemus, many Hispanics in Richmond said that even though they no longer attended church, their religion remained important to them. This confirms research findings that Hispanics who said they had no religion represent a small subset; many more Hispanics are living rather secular lives but still identify themselves as Catholics or Christians. The phenomenon is similar to that of “cultural Jews,” said Roberto Suro, director of the Pew Hispanic Center.
“You can feel very strongly about the Virgin of Guadalupe and believe your children ought to be baptized, and still not participate in the Catholic Church or make it a major factor in your life,” Mr. Suro said.
Richmond and adjacent Chesterfield County have a rapidly growing and diverse Hispanic population, with immigrants from the Caribbean, Central America, Colombia and Mexico. Some are new arrivals, but many have been in the United States for years and resettled here from Northeastern and Southern states, attracted by the area’s jobs, relatively affordable housing and receptive local governments.
The increase in the Hispanic population has meant a proliferation of churches. But even when their own churches are thriving, Hispanic ministers say that most Hispanics they approach are not interested.
“Church is not very popular,” said Francisco Hernandez, who is pastor with his wife, Connie, of the Iglesia de Dios Alfa y Omega, a Pentecostal church with 400 members. “The majority don’t go, and those who go, go one time.”
Asked why, he said that his church’s strict rules were a hard sell, adding, “People like a superficial religion.”
This may be true, and a few young Hispanic women said in interviews that they avoided strict evangelical churches because they frowned on women wearing pants or makeup. However, many more Hispanics said they were simply too busy to attend any church. They said Sunday is a work day, or it is their only day off to wash clothes, go to the market, do errands and relax.
Before Mirna E. Amaya and her husband bought their restaurant, Palacio Latino, three years ago — and when she lived in Maryland — she went to Mass every Sunday. Now she says she is working too hard to go, even though she says she misses it.
“In El Salvador, people went to the church because there’s nothing much else to do,” Mrs. Amaya said.
She said that some of her women friends had stopped going because they became disillusioned with the Catholic Church after the priest sexual abuse scandals. But she said the Roman Catholic Church was still her preference. The closest parish, St. Augustine Catholic Church, has bent over backward to minister to Hispanics. It offers Mass in Spanish, classes in English, a medical van, job assistance and an instant community for lonely new arrivals. The Sunday Spanish Mass is standing room only.
And yet, the pastor, Msgr. Michael Schmied, also the vicar for the diocese’s Hispanic Apostolate, said: “My fear is the strength of secularization, the influence of Americanized pop culture. Is the spiritual tradition of the church, Catholic and Protestant, strong enough to withstand the secularizing cultural influences?”
Jesus Cerritos, a 37-year-old construction worker who immigrated from Mexico 18 years ago, said he spent his weekends running errands, going to Wal-Mart and watching television. His children, ages 11 and 9, tell him that church is boring and that they have no desire to go, but Mr. Cerritos has mixed feelings.
“Here, the people get more materialistic,” Mr. Cerritos said. “The culture here is really barren. There’s no traditions.”
If he were still living in his hometown of Guanajuato, he said, “I would probably go to church.”
And, a bonus letter on gender and brains and whatnot:
Re “Pas de Deux of Sexuality is Written in the Genes” (April 10): Nicholas Wade concludes that sex differences in the brain are responsible for the differing ways that women and men express their sexuality. In assuming that brain structure “is written in the genes,” Mr. Wade completely overlooks environmental influences on brain development.
There is ample evidence from the field of neuroscience that patterns of neural connections, and therefore brain organization, change constantly with experience. Indeed, contrary to Mr. Wade’s claim that distinct patterns in female and male brains exist “despite the heavy influences of culture,” culture may in fact be the cause of many of these differences. Mr. Wade’s views notwithstanding, the nature/nurture controversy is far from being resolved.
Alison Nash
New Paltz, N.Y.
By JOHN NOBLE WILFORD
CHICAGO — Observed in the wild and tested in captivity, chimpanzees invite comparison with humans, their close relatives. They bear a family resemblance that fascinates people, and scientists see increasing evidence of similarities in chimp behavior and skills, making some of them think on the vagaries of evolution.
For some time, paleontologists and evolutionary biologists have known that chimp ancestors were the last line of today’s apes to diverge from the branch that led to humans, probably six million, maybe four million years ago. More recent examination shows that despite profound differences in the two species, just a 1.23 percent difference in their genes separates Homo sapiens from chimpanzees, Pan troglodytes.
And certain similarities between the two species, scientists say, go beyond expressive faces and opposable thumbs.
Chimps display a remarkable range of behavior and talent. They make and use simple tools, hunt in groups and engage in aggressive, violent acts. They are social creatures that appear to be capable of empathy, altruism, self-awareness, cooperation in problem solving and learning through example and experience. Chimps even outperform humans in some memory tasks.
“Fifty years ago, we knew next to nothing about chimpanzees,” said Andrew Whiten, an evolutionary psychologist at the University of St. Andrews in Scotland. “You could not have predicted the richness and complexity of chimp culture that we know now.”
Jane Goodall, a young English woman working in Africa in the 1960s, began changing perceptions. At first, experts disputed her reports of chimps’ using tools and social behavior. The experts especially objected to her references to chimp culture. Just humans, they insisted, had “culture.”
“Jane suffered early rejection by the establishment,” Richard Wrangham, a Harvard anthropologist, said. “Now, the people who say chimpanzees don’t have emotions and culture are the ones rejected.”
The new consensus framed discussions in March at a symposium, “The Mind of the Chimpanzee,” at the Lincoln Park Zoo here. More than 300 primatologists and other scientists reviewed accumulating knowledge of chimps’ cognitive abilities.
After one session, Frans de Waal of Emory University said that as recently as a decade ago there was still no firm consensus on many of the social relationships of chimps. “You don’t hear any debate now,” he said.
In his own studies at the Yerkes Primate Research Center at Emory, Dr. de Waal found that chimps as social animals have had to constrain and alter their behavior in various ways, as have humans. It is a part of ape inheritance, he said, and in the case of humans, the basis for morality. The provocative interpretation was advanced in his recent book, “Primates and Philosophers.”
Other reports shortly before the symposium had elaborated on the abilities of chimps as toolmakers. Jill Pruetz, a primatologist at Iowa State University, described 22 examples of chimps in Senegal making stick spears to hunt smaller primates for their meat. Dr. Goodall was the first to call attention to chimps as hunting carnivores, not strictly vegetarians.
Dr. Pruetz observed several chimps jabbing the spears into hollow tree trunks where bush babies often dwell. Just one attempt was successful. Previously, chimps had been seen using sticks mainly to extract termites from their nests.
A team of archaeologists led by Julio Mercader of the University of Calgary reported finding stones in Ivory Coast that chimps used 4,300 years ago to crack nuts. Today’s chimps have often been videotaped using rocks as a hammer to open nuts. The old stones with starch residues from nuts, the researchers said, were the earliest strong evidence of chimp tool use, and the finding suggested that chimps had learned the skill on their own, rather than copying humans.
Other researchers combine field work showing chimp behavior in natural habitats with laboratory experiments that are created to disclose their underlying intelligence — what scientists call their “cognitive reserve.”
For example, chimps on their own would not sit at a computer responding with rapid touches on the screen as a test of their immediate memory. Videos of their doing just that at Kyoto University in Japan especially impressed the symposium scientists.
Tetsuro Matsuzawa, a Kyoto primatologist, described a young chimp watching as numbers 1 through 9 flashed on the computer screen at random positions. Then the numbers disappeared in no more than a second. White squares remained where the numbers had been. The chimp casually but swiftly pressed the squares, calling back the numbers in ascending order — 1, 2, 3, etc.
The test was repeated several times, with the numbers and squares in different places. The chimp, which had months of training accompanied by promised food rewards, almost never failed to remember where the numbers had been. The video included scenes of a human failing the test, seldom recalling more than one or two numbers, if any.
“Humans can’t do it,” Dr. Matsuzawa said. “Chimpanzees are superior to humans in this task.”
Dr. Matsuzawa suggested that early human species “lost the immediate memory and, in return, learned symbolization, the language skills.”
“I call this the trade-off theory,” he continued. “If you want a capability like better immediate memory, you have to lose some other capability.”
Other experiments at Kyoto’s primate center demonstrated the ability of chimps to recognize themselves and focus attention on others. Masaki Tomonaga, who conducted the tests, said that an infant made eye with its mother at about 2 months and that sometime after the first year was able to maintain a gaze as the mother moved about.
Dr. Tomonaga said such “gaze following” developed in humans about the same age, “though infant humans generally have more complex interactions.”
Misato Hayashi, also from Kyoto, described experiments with infant chimps’ manipulating nesting cups and square and cylindrical blocks. They were slower to learn than humans, but the manual dexterity was there. A human starts stacking blocks shortly after age 1, he said; chimps are almost 3 before getting the hang of it.
In experiments with mirrors, researchers showed that chimps had an awareness of themselves that is absent in monkeys but present in dolphins and all the great apes. Similar tests by Emory scientists showed some self-recognition among elephants.
These behaviors were reported by Dr. de Waal and his associate J. M. Plotnik, who said that they “may suggest convergent cognitive evolution probably related to complex sociality and cooperation well documented in both chimpanzees and elephants.”
Other researchers said that when confronted with problems obtaining food from the other side of a fence, chimps were not only clever on their own and often competitive with a fellow chimp, but they also showed a willingness to cooperate with one another to get the job done.
Brian Hare of Duke University and the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, said bonobos outperformed their chimp relatives in cooperative tasks and shared food more readily.
The emotions of caring and mourning have been observed, as in the case of the chimp mother that carried on her back the corpse of her 2-year-old daughter for days after she had died. After fights between two chimps, scientists said, others in the group were seen consoling the loser and acting as mediators to restore peace.
Devyn Carter of Emory described the sympathetic response to a chimp named Knuckles, who was afflicted with cerebral palsy. No fellow chimp was seen to take advantage of his disability. Even the alpha male gently groomed Knuckles.
Dr. Wrangham of Harvard said the challenge to primatologists working in the field was to learn how much of the behavior and “surplus cognitive capacity” observed in captivity applied in the wild.
The answer seems to vary from one isolated chimp community to another. Scientists said that indicated the role of social learning — picking up skills by emulation — and responses to different opportunities in separate cultures.
At Gombe, the site in Tanzania where Dr. Goodall made a name for herself, the chimps with stick tools are accomplished extractors of termites from their nests. But termite fishing is rare in Bossou, Guinea. At Bossou, and not Gombe, chimps have learned to make use of many other tools, including stones for cracking nuts.
Dora Biro of the University of Oxford in England has studied tool use by chimps at the Bossou site. They fold leaves in a mat to sponge water out of tree hollows and scoop algae off stream surfaces. They collect edible ants with sticks. They take stouter tree branches and pound the juicy palm fiber to a pulp, preparing another favorite food.
Videos of Bossou nutcrackers show adult chimps, often female, placing a nut on a flat stone anvil and slamming down on it with a smaller rock. Two or three youngsters sit around watching. The adults do not appear to be giving instructions, except by example.
“What we’ve learned is that manipulation of objects begins around 1 year of age,” Dr. Biro said. “If it involves two or three objects, as in cracking nuts, that happens at 3 ½ to 5 years. If it is not learned by 6 or 7, it will never be acquired.”
At a dense forest in the Congo Republic, Crickette M. Sanz of the Max Planck institute said the chimps seemed as curious about her as she was about them. Groups came forward, calling others to join them. Sometimes, they sat with her for hours, eating fruit, grooming and even mating.
For a more detached study, Dr. Sanz deployed 18 video cameras at remote locations and recorded 84 hours of chimp tool use. Leaf sponging was the simplest, she concluded, and collecting honey with a long stick required the most effort and risk, with termite fishing having “the highest element of success.”
Dr. Sanz, who has worked with her husband, David B. Morgan, on some of the research, described mother chimps’ carefully withdrawing from a hole sticks swarming with black termites while their infants looked on. These social interactions, she said, passed on essential techniques and behaviors to the next generation.
“Socially transmitted adjustable behavior,” Dr. de Waal said, is a hallmark of culture.
Chimp behavior sometimes turns violent, particularly in territorial clashes. In Uganda, John Mitani of the University of Michigan observed chimp patrols regularly policing the forest boundaries of their communities. One patrol was seen assaulting an adult male, killing and emasculating him.
Kristin Bonnie, another Emory primatologist, said the transmission of behavior could be benign and spontaneous, with the prospect of reward being secondary. “It is the desire to act like others, an identification with certain others,” she explained, citing as an example the way chimps usually clasp hands while grooming each other.
At the symposium, researchers said the interest in learning more about chimps was not just a case of knowledge for the sake of knowledge. Their behavior and intelligence, scientists say, may offer insights into the abilities of early human ancestors like Australopithecus afarensis, the apelike “Lucy” species that thrived more than three million years ago. A more urgent motivation for the research, primatologists say, is that these are sentient beings and the closest living relatives of humans, and their survival is threatened.
Elizabeth V. Lonsdorf, a primatologist at the Lincoln Park Zoo and a symposium organizer, said researchers needed “to keep their eyes out for ways to improve the care of chimpanzees.”
Diseases like ebola and anthrax are taking their toll. Hunting chimps for “bush meat” is increasing. Many of the forest habitats of chimps in central Africa are being cut by loggers and land developers. As a result, Dr. Lonsdorf said, “Groups of the animals are getting closer together, which increased the threat of chimp violence and territorial disputes.”
Dr. Goodall recalled that when she went to Africa nearly a half-century ago, at least a million chimps lived in the continent, and “now there are perhaps only 150,000.” In that time, they have impressed scientists with physical and emotional reminders of their kinship to humans and their occasional triumphs over them at a computer screen.
On the Spanish Flu, and how intervention saved lives
How (and How Not) to Battle Flu: A Tale of 23 Cities
By NICHOLAS BAKALAR
When the Spanish flu reached the United States in the summer of 1918, it seemed to confine itself to military camps. But when it arrived in Philadelphia in September, it struck with a vengeance.
By the time officials there grasped the threat of the virus, it was too late. The disease was rampaging through the population, partly because the city had allowed large public gatherings, including a citywide parade in support of a World War I loan drive, to go on as planned. In four months, more than 12,000 Philadelphians died, an excess death rate of 719 people for every 100,000 inhabitants.
The story was quite different in St. Louis. Two weeks before Philadelphia officials began to react, doctors in St. Louis persuaded the city to require that influenza cases be registered with the health department. And two days after the first civilian cases, police officers helped the department enforce a shutdown of schools, churches and other gathering places. Infected people were quarantined in their homes.
Excess deaths in St. Louis were 347 per 100,000 people, less than half the rate in Philadelphia. Early action appeared to have saved thousands of lives.
Scientists are still studying the 1918 pandemic, the deadliest of the 20th century, looking for lessons for future outbreaks — including the possibility that H5N1, the avian influenza virus, could mutate into a form spread easily from human to human. This month, researchers published two new studies in The Proceedings of the National Academy of Sciences comparing public-health responses in cities like St. Louis and Philadelphia.
Using mathematical models, they reported that such large differences in death rates could be explained by the ways the cities carried out prevention measures, especially in their timing. Cities that instituted quarantine, school closings, bans on public gatherings and other such procedures early in the epidemic had peak death rates 30 percent to 50 percent lower than those that did not.
“It had been received wisdom that these interventions didn’t work,” said Dr. Richard Hatchett, the lead author of one of the studies, “because they looked at the variability between cities and concluded that there was some other factor than the interventions that caused the differing outcomes.
“That we were able to go back and ask the right questions,” Dr. Hatchett said, “is a function of a lot of modeling work that we did previously.”
Dr. Hatchett, who is a researcher at the National Institutes of Health, said the findings might hold lessons for the 21st century. “When multiple interventions were introduced early, they were very effective in 1918,” he said, “and that certainly offers hope that they would be similarly useful in an epidemic today if we didn’t have an effective vaccine.”
A two-week difference in response times, according to the researchers, is long enough for the number of people infected in an influenza epidemic to double three to five times.
Dr. Martin Cetron, director for global migration and quarantine at the federal Centers for Disease Control and Prevention in Atlanta, found reason for optimism in the study results.
“The thing I find encouraging about the Hatchett paper,” he said, “is that when you look back to 1918, you find that those who used nonpharmaceutical measures effectively were able to mitigate the impact of the severe pandemics, and this is consistent with some of the 21st-century simulation models.”
The second study, in the same issue of The Proceedings, suggests that in one sense preventive measures can be too effective. In an influenza epidemic, a certain number of people survive the illness and are immune to reinfection. As these numbers increase, the epidemic fades.
But an effective prevention program without a vaccine can leave enough people uninfected and still susceptible to the virus to start the epidemic again as soon as the controls are lifted. This is what happened in St. Louis. On Nov. 14, 1918 — in high spirits three days after the armistice that ended the war, and with influenza cases declining — the city reopened schools and businesses. Two weeks later, the second wave of the epidemic struck, this time with children making up 30 percent to 40 percent of the infections. Controls were immediately reinstituted.
The study examined the course of the epidemic in 23 cities: San Francisco, St. Louis, Milwaukee and Kansas City, Mo., had the most effective prevention programs, and time was of the essence. If restrictions were introduced too late or lifted too early, success rates declined substantially.
Neil Ferguson, a co-author of the second study and a professor of epidemiology at Imperial College London, explained in a telephone interview that the most successful interventions were in communities where the political and health authorities broadly agreed on what needed to be done and got significant cooperation from the public.
The key, Dr. Ferguson said, is to tune an imperfect intervention perfectly so that a single peak of minimal size is the result. Although no cities succeeded in doing this, those that got closest, like St. Louis, carried out early interventions before the first peak, and then reinstituted them when transmission rates began to rise again.
What these results mean for a future epidemic is not clear. “If avian flu became a pandemic tomorrow,” Dr. Ferguson said, “we would start a crash program to make a vaccine.”
But he added that rigid preventive measures like quarantines, mandated mask wearing and widespread business closings would still need to be put in place.
“What our study shows,” he continued, “is that interventions even without a vaccine can be effective in blocking transmission. What’s much less certain is whether society is prepared to bear the costs of implementing such intrusive and costly measures for the months that would be required to manufacture a vaccine.”
For Some Hispanics, Coming to America Also Means Abandoning Religion
For Some Hispanics, Coming to America Also Means Abandoning Religion
By LAURIE GOODSTEIN
RICHMOND, Va. — On Sunday afternoons, when the local Roman Catholic church holds Mass for Spanish-speaking Catholics, Edgar Chilín is playing soccer in a league with hundreds of Hispanic players.
As a child in Guatemala, Mr. Chilín attended Mass every Sunday. But after immigrating to the United States 25 years ago, he and his family lost the churchgoing habit. “We pray to God when we feel the need to,” he said, “but when we come here to America we don’t feel the need.”
A wave of research shows that increasing percentages of Hispanics are abandoning church, suggesting to researchers that along with assimilation comes a measure of secularization.
Several studies show that Hispanics are just as likely as other Americans to identify themselves as having “no religion,” and to not affiliate with a church. Those who describe themselves as secular are, without question, a small minority among Hispanics — as they are among Americans at large. But, in contrast to many of the non-Hispanic Americans who identify themselves as secular, most of the Hispanics say they were once religious.
The Roman Catholic Church, the religious home for most Hispanics, is experiencing the greatest exodus. While many former Catholics join evangelical or Pentecostal churches, the recent research shows that many of them leave church altogether.
“Migrating to the U.S. means you have the freedom to create your own identity,” said Keo Cavalcanti, a sociologist at James Madison University in Harrisonburg, Va., and a co-author of a recent study that found a trend toward secularization among Hispanics in Richmond. “When people get here they realize that maintaining that pro forma display of religiosity is not essential to doing well.”
A separate study of 4,000 Hispanics to be released this month by the Pew Forum on Religion and Public Life and the Pew Hispanic Center found that 8 percent of them said they had “no religion” — similar to the 11 percent in the general public. Of the Hispanics who claimed no religion, two-thirds said they had once been religious. Thirty-nine percent of the Hispanics who said they had no religion were former Catholics.
Hispanics from Cuba were the most secular national group, at 14 percent, followed by Central Americans at 12 percent, Puerto Ricans and Dominicans at 9 percent, and South Americans at 8 percent, the Pew poll found. Mexicans in this country were the least likely to say they had no religion, at 7 percent.
A larger survey, called the American Religious Identification Survey, a study of 50,000 adults, including 3,000 Hispanics, found that the percentage of Hispanics who identified themselves as having no religion more than doubled from 1990 to 2001, to 13 percent from 6 percent.
This change is happening even though many Hispanics immigrated from countries steeped in religion, where saints’ days and festivals mark the passage of time, and grandmothers round up their progeny each Sunday to go to Mass.
“They come, they adopt the American way, and part of the American way is moving towards no religion,” said Ariela Keysar, associate director of the Institute for the Study of Secularism in Society and Culture at Trinity College in Hartford.
Each year, Diana Lemus — a real estate agent and owner of Happy Mart, a busy Latino market in Richmond — makes New Year’s resolutions that include working out more, getting out of debt, being a better mother and attending church once a week.
Ms. Lemus, a first-generation immigrant, said that this year she had kept all of them, except going to church — and spends Sunday mornings at the gym. She thinks her faith is important, but said that perhaps she has grown “too materialistic.”
“I need God in my life, but I told the pastor, I get sleepy,” she said. “You have to stay in church from 1:30 to 5. I think if services were shorter, more entertaining.”
Like Ms. Lemus, many Hispanics in Richmond said that even though they no longer attended church, their religion remained important to them. This confirms research findings that Hispanics who said they had no religion represent a small subset; many more Hispanics are living rather secular lives but still identify themselves as Catholics or Christians. The phenomenon is similar to that of “cultural Jews,” said Roberto Suro, director of the Pew Hispanic Center.
“You can feel very strongly about the Virgin of Guadalupe and believe your children ought to be baptized, and still not participate in the Catholic Church or make it a major factor in your life,” Mr. Suro said.
Richmond and adjacent Chesterfield County have a rapidly growing and diverse Hispanic population, with immigrants from the Caribbean, Central America, Colombia and Mexico. Some are new arrivals, but many have been in the United States for years and resettled here from Northeastern and Southern states, attracted by the area’s jobs, relatively affordable housing and receptive local governments.
The increase in the Hispanic population has meant a proliferation of churches. But even when their own churches are thriving, Hispanic ministers say that most Hispanics they approach are not interested.
“Church is not very popular,” said Francisco Hernandez, who is pastor with his wife, Connie, of the Iglesia de Dios Alfa y Omega, a Pentecostal church with 400 members. “The majority don’t go, and those who go, go one time.”
Asked why, he said that his church’s strict rules were a hard sell, adding, “People like a superficial religion.”
This may be true, and a few young Hispanic women said in interviews that they avoided strict evangelical churches because they frowned on women wearing pants or makeup. However, many more Hispanics said they were simply too busy to attend any church. They said Sunday is a work day, or it is their only day off to wash clothes, go to the market, do errands and relax.
Before Mirna E. Amaya and her husband bought their restaurant, Palacio Latino, three years ago — and when she lived in Maryland — she went to Mass every Sunday. Now she says she is working too hard to go, even though she says she misses it.
“In El Salvador, people went to the church because there’s nothing much else to do,” Mrs. Amaya said.
She said that some of her women friends had stopped going because they became disillusioned with the Catholic Church after the priest sexual abuse scandals. But she said the Roman Catholic Church was still her preference. The closest parish, St. Augustine Catholic Church, has bent over backward to minister to Hispanics. It offers Mass in Spanish, classes in English, a medical van, job assistance and an instant community for lonely new arrivals. The Sunday Spanish Mass is standing room only.
And yet, the pastor, Msgr. Michael Schmied, also the vicar for the diocese’s Hispanic Apostolate, said: “My fear is the strength of secularization, the influence of Americanized pop culture. Is the spiritual tradition of the church, Catholic and Protestant, strong enough to withstand the secularizing cultural influences?”
Jesus Cerritos, a 37-year-old construction worker who immigrated from Mexico 18 years ago, said he spent his weekends running errands, going to Wal-Mart and watching television. His children, ages 11 and 9, tell him that church is boring and that they have no desire to go, but Mr. Cerritos has mixed feelings.
“Here, the people get more materialistic,” Mr. Cerritos said. “The culture here is really barren. There’s no traditions.”
If he were still living in his hometown of Guanajuato, he said, “I would probably go to church.”
And, a bonus letter on gender and brains and whatnot:
Re “Pas de Deux of Sexuality is Written in the Genes” (April 10): Nicholas Wade concludes that sex differences in the brain are responsible for the differing ways that women and men express their sexuality. In assuming that brain structure “is written in the genes,” Mr. Wade completely overlooks environmental influences on brain development.
There is ample evidence from the field of neuroscience that patterns of neural connections, and therefore brain organization, change constantly with experience. Indeed, contrary to Mr. Wade’s claim that distinct patterns in female and male brains exist “despite the heavy influences of culture,” culture may in fact be the cause of many of these differences. Mr. Wade’s views notwithstanding, the nature/nurture controversy is far from being resolved.
Alison Nash
New Paltz, N.Y.
