When Young Men Are Scarce, They're More Likely To Play The Field Than To Propose
ScienceDaily (June 10, 2009) — In places where young women outnumber young men, research shows the hemlines rise but the marriage rates don't because the young men feel less pressure to settle down as more women compete for their affections.
But when those men reach their 30s, the reverse is true and proportionately more older men are married in areas where women outnumber men.
Daniel Kruger, a University of Michigan researcher who studies evolution and how it relates to contemporary behavior, looked at the 50 largest metropolitan areas in the United States to test his hypothesis on how the balance between women and men affects marital patterns. Results showed that men aged 20-24 are more likely to cruise than to commit if they live in an area with more women than men.
One would think that rationally, fewer young men than women would naturally lead to proportionately more young men getting married, but that's not the case.
"Marriage patterns aren't rational because men and women have somewhat different reproductive strategies," Kruger said. "Men have a greater reproductive benefit than women from having a greater quantity of relationships. If they can leverage their scarcity into attracting multiple short-term partners, they will not have as much of an incentive to settle down."
There are about nine unmarried men for every 10 unmarried women in Birmingham, Memphis, New Orleans, and Richmond-Petersburg, Virginia, Kruger says. Philadelphia, Washington, DC, Baltimore, and New York metropolitan areas are tied for the next region where women are relatively most plentiful. In these areas, about 84 percent of the men aged 20-24 are unmarried. In Las Vegas, San Diego, Salt Lake City, Austin, and Phoenix, there are about nine unmarried women for every 10 unmarried men. In these areas, about 77 percent of the men aged 20-24 are unmarried.
Once those young men hit their 30s, they tend to shift from seeking short-term relationships to entering into committed relationships. That's because when women evaluate partners for short-term relationships they value physical features signaling the kind of genes that would be passed on to potential offspring, which may be the only legacy of men who don't stick around for child rearing. These physical features decline as men age, making it more difficult to lure women into uncommitted relationships.
"You see a complete reversal in the pattern," Kruger said, and thus, proportionately more older men are married when women outnumber men.
So, does this mean that middle aged women in these cities get a break? Not really, Kruger says. The higher marital rates for older men likely benefit women who are substantially younger than their husbands, because older men still prefer partners with higher reproductive potential.
The ratio of men to women has other aspects, as well. For instance, studies have shown that when women outnumber men, hemlines actually rise, overall, as women to do more to physically attract men. Also, the rates of divorce and out-of-wedlock births are higher, and interests in women's rights increases. Surpluses of men tend to be associated with more conservative social norms and restricted roles for women.
Showing posts with label social. Show all posts
Showing posts with label social. Show all posts
Wednesday, July 8, 2009
Friday, June 19, 2009
NO-FATHERS DAY: Remote Group Has No Dads, And Never Did
http://news.nationalgeographic.com/news/2009/06/090619-fathers-day-2009-no-fathers.html
NO-FATHERS DAY: Remote Group Has No Dads, And Never Did
Brian Handwerkfor National Geographic News
June 18, 2009
What would Father's Day—and every other day—be like without fathers? Maybe not so bad, according to experts on the Mosuo culture of the Chinese Himalaya.
The women of this matrilineal society shun marriage and raise their kids in homes with their entire extended families—but no dads.
By most accounts, children seem to do just fine under the arrangement.
"They are a society that we know hasn't had marriage for a thousand years, and they've been able to raise kids successfully," said Stephanie Coontz, family studies professor at the Evergreen State College in Olympia, Washington.
No Fathers: It Makes Genetic Sense?
Men of the Mosuo, who live around Lugu Lake on the border between Yunnan and Sichuan Provinces, do help to raise kids—just not their own, with whom the men typically have only limited relationships.
Instead the men help look after all the children born to their own sisters, aunts, and other women of the family.
Rather than "one father with a kid, it will be four or five uncles. That [father] role is shared among a number of people, and these are very large extended families," explained John Lombard, director of the Lugu Lake Mosuo Cultural Development Association.
The unusual parenting arrangement makes genetic sense, in terms of extending the family line—and many Mosuo men actually think of it that way, Lombard said.
"If you [father] a child with another woman, you can never be absolutely sure that the child really shares your genes," he said. "But if your sister has a child, you can be 100 percent sure that the kid shares some of your genes."
The women of the Mosuo's agricultural villages head the households, make business decisions, and own property, which they pass on to their matrilineal heirs.
In the unique Mosuo tradition called the walking marriage, women invite men to visit their rooms at night—and to leave in the morning.
Women may also change partners as often as they like, and promiscuity carries no social stigma. The practice has made the Mosuo famous, particularly to male Chinese tourists, many of whom see the walking marriages as evidence of sexual liberation and wanton lust, experts say. Though there are tourist-oriented brothels in Mosuo villages, most are staffed with non-Mosuo women and are considered shameful by the Mosuo, according to the the Lugu Lake Mosuo Cultural Development Association Web site.
"I think sometimes the media gets carried away with the possibility that the women can have all these husbands," said filmmaker Xiaoli Zhou, who produced and reported the 2006 documentary on the Mosuo, The Women's Kingdom.
In fact, most Mosuo women don't change walking-marriage partners very frequently. And they rarely carry on more than one romantic relationship at a time.
"Many of the women I interviewed had only had one or two relationships in their lives," Zhou said.
Family First
The lack of live-in fathers shouldn't be taken as evidence that the Mosuo don't value family life, said Lombard, of the Lugu Lake Mosuo Cultural Development Association.
In fact, they value it above all other relationships—particularly those founded on the sometimes fickle feelings of male-female amour, he said.
Extended families of siblings, uncles, aunts, and others are said to be extremely stable, Lombard added.
For example, there are no divorces to destablize the families. And even the death of a child's biological father has little effect on the family, given the father's distance from the family and the extensive support network in the household.
Brent Huffman, co-producer of The Women's Kingdom, said, "The society does kind of create this question: Are fathers really necessary?
"It's hard to think of in Western society, but there, it works."
NO-FATHERS DAY: Remote Group Has No Dads, And Never Did
Brian Handwerkfor National Geographic News
June 18, 2009
What would Father's Day—and every other day—be like without fathers? Maybe not so bad, according to experts on the Mosuo culture of the Chinese Himalaya.
The women of this matrilineal society shun marriage and raise their kids in homes with their entire extended families—but no dads.
By most accounts, children seem to do just fine under the arrangement.
"They are a society that we know hasn't had marriage for a thousand years, and they've been able to raise kids successfully," said Stephanie Coontz, family studies professor at the Evergreen State College in Olympia, Washington.
No Fathers: It Makes Genetic Sense?
Men of the Mosuo, who live around Lugu Lake on the border between Yunnan and Sichuan Provinces, do help to raise kids—just not their own, with whom the men typically have only limited relationships.
Instead the men help look after all the children born to their own sisters, aunts, and other women of the family.
Rather than "one father with a kid, it will be four or five uncles. That [father] role is shared among a number of people, and these are very large extended families," explained John Lombard, director of the Lugu Lake Mosuo Cultural Development Association.
The unusual parenting arrangement makes genetic sense, in terms of extending the family line—and many Mosuo men actually think of it that way, Lombard said.
"If you [father] a child with another woman, you can never be absolutely sure that the child really shares your genes," he said. "But if your sister has a child, you can be 100 percent sure that the kid shares some of your genes."
The women of the Mosuo's agricultural villages head the households, make business decisions, and own property, which they pass on to their matrilineal heirs.
In the unique Mosuo tradition called the walking marriage, women invite men to visit their rooms at night—and to leave in the morning.
Women may also change partners as often as they like, and promiscuity carries no social stigma. The practice has made the Mosuo famous, particularly to male Chinese tourists, many of whom see the walking marriages as evidence of sexual liberation and wanton lust, experts say. Though there are tourist-oriented brothels in Mosuo villages, most are staffed with non-Mosuo women and are considered shameful by the Mosuo, according to the the Lugu Lake Mosuo Cultural Development Association Web site.
"I think sometimes the media gets carried away with the possibility that the women can have all these husbands," said filmmaker Xiaoli Zhou, who produced and reported the 2006 documentary on the Mosuo, The Women's Kingdom.
In fact, most Mosuo women don't change walking-marriage partners very frequently. And they rarely carry on more than one romantic relationship at a time.
"Many of the women I interviewed had only had one or two relationships in their lives," Zhou said.
Family First
The lack of live-in fathers shouldn't be taken as evidence that the Mosuo don't value family life, said Lombard, of the Lugu Lake Mosuo Cultural Development Association.
In fact, they value it above all other relationships—particularly those founded on the sometimes fickle feelings of male-female amour, he said.
Extended families of siblings, uncles, aunts, and others are said to be extremely stable, Lombard added.
For example, there are no divorces to destablize the families. And even the death of a child's biological father has little effect on the family, given the father's distance from the family and the extensive support network in the household.
Brent Huffman, co-producer of The Women's Kingdom, said, "The society does kind of create this question: Are fathers really necessary?
"It's hard to think of in Western society, but there, it works."
Wednesday, June 17, 2009
Apes Laugh, Tickle Study Finds
http://news.nationalgeographic.com/news/2009/06/090604-apes-laugh-tickle-chimps-gorillas.html
Apes Laugh, Tickle Study Finds
Brian Handwerk for National Geographic News
June 4, 2009
What happens if you tickle a gorilla? According to a new study, the ape laughs—which would mean we're not the only animals born with funny bones.
By tickling young gorillas, chimpanzees, bonobos, and orangutans, researchers say they learned that all great apes laugh.
Their findings suggest we inherited our own ability to laugh from the last common ancestor from which humans and great apes evolved, which lived 10 to 16 million years ago.
Primatologist and psychologist Marina Davila Ross of the U.K.'s University of Portsmouth led a team that tickled the necks, feet, palms, and armpits of infant and juvenile apes as well as human babies. The team recorded more than 800 of the resulting giggles and guffaws.
(go to the link to hear laughter recordings)
Mapping the audible similarities and differences in laughs across the five species, the researchers created an acoustic family tree of human and great ape laughter.
The tree, they found, closely matched the standard genetics-based evolutionary tree of primates.
"So we concluded that these vocalizations all share the same common ancestry," Davila Ross explained.
But even the most casual listener can tell a human laugh from an ape laugh. Davila Ross points out that human laughter has distinct differences from ape laughter, most likely because humans have evolved much more rapidly than apes during the past five million years.
And at least one great mystery remains: What purpose does ape laughter serve?
"I'm very keen," Davila Ross said, "on learning how laughter is being used among great apes as compared to humans."
Is It Really Laughter?
It's previously been argued that chimps chuckle, but their method—"laughing" on both the exhale and inhale—had been deemed too different from the human, exhale-only laugh.
The tickle study, however, found evidence that most ape laughter, especially among gorillas and bonobos, shares key traits with human laughter.
Like humans, for example, gorillas and bonobos laughed only while exhaling—leading University of Wisconsin zoologist and psychologist Charles Snowdon, who was not involved in the study, to conclude that, "contrary to current views, the exhalation-only laughter is not uniquely human but is found in our ape ancestors."
Furthermore, gorillas' and bonobos' exhaling breaths during laughter lasted three to four times longer than during normal breathing.
This type of breath control, considered important in speech evolution, had also been thought to be unique to humans.
"Play Faces" to Chimp Chuckles?
Convinced by what he calls an "admirable" study, primatologist Frans de Waal said from now on he'd use "laughter" to describe what scientists have traditionally called a chimp's play face.
The combination of common facial expressions, breathing patterns, and sounds has led de Waal to the conclusion that our laughter has prehistoric, ape-based origins.
What's more, "the primate laugh is given in playful contexts, and as such has a strong similarity to the human laugh," added de Waal, who was not involved in the tickle study.
"Tickling and wrestling are the situations in which primates laugh—and I use the term 'laugh' now advisedly, because the evidence from this study is very strong that their display is evolutionarily related to the human laugh."
Next Up: Rat Laughter?
Primates have apparently packed a lot of laughter into the last 10 to 16 million years, but there's a chance the chuckle originated even earlier: Tickle-induced "laughter" has also been reported in rats.
The idea remains controversial, but it could suggest that our funny bone evolved much closer to the trunk of mammals' evolutionary tree.
SOURCES AND RELATED WEB SITES
University of Portsmouth: Marina Davila Ross
Emory University: Frans B.M. de Waal
University of Wisconsin: Charles Snowdon
Apes Laugh, Tickle Study Finds
Brian Handwerk for National Geographic News
June 4, 2009
What happens if you tickle a gorilla? According to a new study, the ape laughs—which would mean we're not the only animals born with funny bones.
By tickling young gorillas, chimpanzees, bonobos, and orangutans, researchers say they learned that all great apes laugh.
Their findings suggest we inherited our own ability to laugh from the last common ancestor from which humans and great apes evolved, which lived 10 to 16 million years ago.
Primatologist and psychologist Marina Davila Ross of the U.K.'s University of Portsmouth led a team that tickled the necks, feet, palms, and armpits of infant and juvenile apes as well as human babies. The team recorded more than 800 of the resulting giggles and guffaws.
(go to the link to hear laughter recordings)
Mapping the audible similarities and differences in laughs across the five species, the researchers created an acoustic family tree of human and great ape laughter.
The tree, they found, closely matched the standard genetics-based evolutionary tree of primates.
"So we concluded that these vocalizations all share the same common ancestry," Davila Ross explained.
But even the most casual listener can tell a human laugh from an ape laugh. Davila Ross points out that human laughter has distinct differences from ape laughter, most likely because humans have evolved much more rapidly than apes during the past five million years.
And at least one great mystery remains: What purpose does ape laughter serve?
"I'm very keen," Davila Ross said, "on learning how laughter is being used among great apes as compared to humans."
Is It Really Laughter?
It's previously been argued that chimps chuckle, but their method—"laughing" on both the exhale and inhale—had been deemed too different from the human, exhale-only laugh.
The tickle study, however, found evidence that most ape laughter, especially among gorillas and bonobos, shares key traits with human laughter.
Like humans, for example, gorillas and bonobos laughed only while exhaling—leading University of Wisconsin zoologist and psychologist Charles Snowdon, who was not involved in the study, to conclude that, "contrary to current views, the exhalation-only laughter is not uniquely human but is found in our ape ancestors."
Furthermore, gorillas' and bonobos' exhaling breaths during laughter lasted three to four times longer than during normal breathing.
This type of breath control, considered important in speech evolution, had also been thought to be unique to humans.
"Play Faces" to Chimp Chuckles?
Convinced by what he calls an "admirable" study, primatologist Frans de Waal said from now on he'd use "laughter" to describe what scientists have traditionally called a chimp's play face.
The combination of common facial expressions, breathing patterns, and sounds has led de Waal to the conclusion that our laughter has prehistoric, ape-based origins.
What's more, "the primate laugh is given in playful contexts, and as such has a strong similarity to the human laugh," added de Waal, who was not involved in the tickle study.
"Tickling and wrestling are the situations in which primates laugh—and I use the term 'laugh' now advisedly, because the evidence from this study is very strong that their display is evolutionarily related to the human laugh."
Next Up: Rat Laughter?
Primates have apparently packed a lot of laughter into the last 10 to 16 million years, but there's a chance the chuckle originated even earlier: Tickle-induced "laughter" has also been reported in rats.
The idea remains controversial, but it could suggest that our funny bone evolved much closer to the trunk of mammals' evolutionary tree.
SOURCES AND RELATED WEB SITES
University of Portsmouth: Marina Davila Ross
Emory University: Frans B.M. de Waal
University of Wisconsin: Charles Snowdon
The Dark Side Of Gifts: Feeling Indebted May Drive People To The Marketplace
http://www.sciencedaily.com/releases/2009/06/090615171632.htm
ScienceDaily (June 17, 2009) — You need to move out of your apartment. Do you call in your friends and family to haul boxes and furniture or contact a moving company? A new study in the Journal of Consumer Research shows that sometimes the emotions connected with asking for favors can actually drive people to the market.
According to the study's author, Jean-Sébastien Marcoux (HEC Montréal), many researchers romanticize gift-giving. "They praise it for humanizing market relationships, for making the market meaningful, and for providing an escape from the commodifying logic of capitalist exchanges," Marcoux writes. Other researchers have examined the dark side of gift giving: the troublesome feelings that arise from social indebtedness. But Marcoux's research examines how feelings of perpetual obligation affect people's attitudes toward the market.
Marcoux conducted a ten-year (1997-2007) ethnographic study in Montréal on moving. His methods involved interviews, observations, photography, and even moving furniture. He chose to study moving because it's an act that can involve the market, the "gift economy," or both. "Moving is a social event particularly favorable to the emergence of reciprocal relations," writes Marcoux. "Moreover, many people who move use both the gift economy and the market to do so."
By studying moving, Marcoux got an in-depth look at people who were often in the midst of traumatic life events, such as divorce, job loss, separation, or death of a loved one. Marcoux found that the guilt and obligation connected with asking for help from family and friends often drove people to seek the simpler transactions of the marketplace.
"It is important to recognize that withholding requests for gifts, services, and favors from significant others can be a driving force for using the market," writes Marcoux. "People use the market to free themselves from the straitjacket of social expectations—from the sense of indebtedness and emotional oppression—which constrains them in their reciprocity relations inside the gift economy," Marcoux concludes.
Journal reference:
Jean-Sébastien Marcoux. Escaping the Gift Economy. Journal of Consumer Research, 2009; 090603081616048 DOI: 10.1086/600485
ScienceDaily (June 17, 2009) — You need to move out of your apartment. Do you call in your friends and family to haul boxes and furniture or contact a moving company? A new study in the Journal of Consumer Research shows that sometimes the emotions connected with asking for favors can actually drive people to the market.
According to the study's author, Jean-Sébastien Marcoux (HEC Montréal), many researchers romanticize gift-giving. "They praise it for humanizing market relationships, for making the market meaningful, and for providing an escape from the commodifying logic of capitalist exchanges," Marcoux writes. Other researchers have examined the dark side of gift giving: the troublesome feelings that arise from social indebtedness. But Marcoux's research examines how feelings of perpetual obligation affect people's attitudes toward the market.
Marcoux conducted a ten-year (1997-2007) ethnographic study in Montréal on moving. His methods involved interviews, observations, photography, and even moving furniture. He chose to study moving because it's an act that can involve the market, the "gift economy," or both. "Moving is a social event particularly favorable to the emergence of reciprocal relations," writes Marcoux. "Moreover, many people who move use both the gift economy and the market to do so."
By studying moving, Marcoux got an in-depth look at people who were often in the midst of traumatic life events, such as divorce, job loss, separation, or death of a loved one. Marcoux found that the guilt and obligation connected with asking for help from family and friends often drove people to seek the simpler transactions of the marketplace.
"It is important to recognize that withholding requests for gifts, services, and favors from significant others can be a driving force for using the market," writes Marcoux. "People use the market to free themselves from the straitjacket of social expectations—from the sense of indebtedness and emotional oppression—which constrains them in their reciprocity relations inside the gift economy," Marcoux concludes.
Journal reference:
Jean-Sébastien Marcoux. Escaping the Gift Economy. Journal of Consumer Research, 2009; 090603081616048 DOI: 10.1086/600485
Thursday, June 11, 2009
Close Social Ties Make Baboons Better Mothers, Study Finds
http://www.sciencedaily.com/releases/2009/06/090610091429.htm
ScienceDaily (June 11, 2009) — Baboons whose mothers have strong relationships with other females are much more likely to survive to adulthood than baboons reared by less social mothers, according to a new study by researchers at UCLA, the University of Pennsylvania and other institutions.
"If you're a baboon, the strength of your mother's relationship with other females is the best predictor of whether you'll live to have children yourself," said Joan Silk, the study's lead author and a UCLA professor of anthropology. "The study adds to mounting evidence of the biological benefits of close relationships among females."
The findings are significant because "survivorship to reproduction is the gold standard in evolutionary biology," said co-author Dorothy Cheney, a professor of biology at the University of Pennsylvania. "Females who raise offspring to a reproductive age are more likely see their genes pass along, so these findings demonstrate an evolutionary advantage to strong relationships with other females. In evolutionary terms, social moms are the fittest moms — at least when it comes to baboons."
The study appears online in the Proceedings of the Royal Society B, a peer-reviewed journal published by the national academy of science of the United Kingdom and the Commonwealth.
Silk, Cheney and seven other researchers from the University of Pennsylvania, the University of Michigan and the University of St. Andrews in Kenya analyzed 17 years worth of records on more than 66 adult female baboons in the Moremi Game Reserve, a 2,000-square-mile national park in Botswana that teems with wildlife.
Collected on the ground by primatologists who tracked the baboons six days a week, 12 months a year, the records reflected the sex and survival rates of baboon offspring, as well as telling details of the mothers' social lives, including their ranking within the group, as measured by the direction of approach/retreat interactions, and the amount of social interactions they had with each of the group's other females.
In addition to showing how often one animal approached another, the records of social interactions included details of grooming, which is known to be the primary form of social interaction in Old World monkeys. The researchers noted how much time — frequency and duration — the females spent grooming each other and how often they solicited grooming from other females.
Of all the factors studied, the strength of a mother's social bonds with another female had the most significant effect on the survival rates of offspring. A mother's dominance rank proved to have no affect on the survival rate of her offspring.
"We really expected dominance status to be more influential than it proved to be," Silk said.
Offspring from the most social mothers turned out to be about one-and-a-half times more likely to survive to adulthood than offspring from the least social mothers.
The strongest social bonds were measured between mothers and adult daughters, followed by sisters and all other potential relationships, including aunts, nieces, cousins and baboons with no familial ties. Bonds between mothers and adult daughters proved to be three times stronger than those between sisters and 10 times stronger than relationships with other females.
"What really matter to these girls are mother-daughter bonds," Silk said. "They're really strong, and they last forever. If your mom is alive, she's one of your top partners, always. But more importantly, it's the strength of these bonds, because females whose bonds with their mothers and daughters were strong had higher offspring survival than females whose bonds with these relatives were weak."
Silk's past research with Jeanne Altmann, the Eugene Higgins Professor of Ecology and Evolutionary Biology at Princeton University, and Susan C. Alberts, a professor of biology at Duke University, on baboons in the Amboseli Basin of Kenya had found a higher survival rate for baboons with social mothers, but the research only tracked offspring through the first year of life.
For the new study, researchers followed offspring from 1 year of age through sexual maturity — roughly 5 years of age. The new study also differs from past baboon research by focusing on the strength and duration of relationships between pairs of females rather than on the amount of social interactions in general.
"The benefit comes not from being wildly social — it's about having close social bonds," said Cheney, who runs the Moremi baboon-tracking project with University of Pennsylvania psychology professor Robert M. Seyfarth.
"These females form strong relationships with particular partners," Silk said. "They don't treat everyone the same. They spend a lot more time with — and a lot more time grooming — some females than others, and these relationships tend to be very long-lasting."
Additional research is needed to determine how the female bonds improve infant survival, but it may have to do with such stress hormones as cortisol, Silk said. Research has shown that prolonged elevations of stress hormones in primates can lead to cardiovascular disease and other serious health problems. Research has also shown that grooming tends to lower these stress hormones in baboons.
"Our research suggests that somehow there is a link between the kind of social relationships you form and the natural, normal stresses that occur in everyday life, and that seems to have — at least in baboons — a long-term effect on reproductive success," Silk said.
Said to share 92 percent of their DNA with humans, baboons are close relatives of humans. Baboons and humans last shared a common ancestor about 18 million years ago. The new findings on social interactions among mothers parallel recent research that has shown health benefits for humans who enjoy particularly close social networks.
"Our findings suggest benefits from forming close relationships are built into us from a long way back," Silk said.
The research received funding from the National Geographic Foundation, the Research Foundation of the University of Pennsylvania, the Institute for Research in Cognitive Science at the University of Pennsylvania, the National Institute of Health and the National Science Foundation.
ScienceDaily (June 11, 2009) — Baboons whose mothers have strong relationships with other females are much more likely to survive to adulthood than baboons reared by less social mothers, according to a new study by researchers at UCLA, the University of Pennsylvania and other institutions.
"If you're a baboon, the strength of your mother's relationship with other females is the best predictor of whether you'll live to have children yourself," said Joan Silk, the study's lead author and a UCLA professor of anthropology. "The study adds to mounting evidence of the biological benefits of close relationships among females."
The findings are significant because "survivorship to reproduction is the gold standard in evolutionary biology," said co-author Dorothy Cheney, a professor of biology at the University of Pennsylvania. "Females who raise offspring to a reproductive age are more likely see their genes pass along, so these findings demonstrate an evolutionary advantage to strong relationships with other females. In evolutionary terms, social moms are the fittest moms — at least when it comes to baboons."
The study appears online in the Proceedings of the Royal Society B, a peer-reviewed journal published by the national academy of science of the United Kingdom and the Commonwealth.
Silk, Cheney and seven other researchers from the University of Pennsylvania, the University of Michigan and the University of St. Andrews in Kenya analyzed 17 years worth of records on more than 66 adult female baboons in the Moremi Game Reserve, a 2,000-square-mile national park in Botswana that teems with wildlife.
Collected on the ground by primatologists who tracked the baboons six days a week, 12 months a year, the records reflected the sex and survival rates of baboon offspring, as well as telling details of the mothers' social lives, including their ranking within the group, as measured by the direction of approach/retreat interactions, and the amount of social interactions they had with each of the group's other females.
In addition to showing how often one animal approached another, the records of social interactions included details of grooming, which is known to be the primary form of social interaction in Old World monkeys. The researchers noted how much time — frequency and duration — the females spent grooming each other and how often they solicited grooming from other females.
Of all the factors studied, the strength of a mother's social bonds with another female had the most significant effect on the survival rates of offspring. A mother's dominance rank proved to have no affect on the survival rate of her offspring.
"We really expected dominance status to be more influential than it proved to be," Silk said.
Offspring from the most social mothers turned out to be about one-and-a-half times more likely to survive to adulthood than offspring from the least social mothers.
The strongest social bonds were measured between mothers and adult daughters, followed by sisters and all other potential relationships, including aunts, nieces, cousins and baboons with no familial ties. Bonds between mothers and adult daughters proved to be three times stronger than those between sisters and 10 times stronger than relationships with other females.
"What really matter to these girls are mother-daughter bonds," Silk said. "They're really strong, and they last forever. If your mom is alive, she's one of your top partners, always. But more importantly, it's the strength of these bonds, because females whose bonds with their mothers and daughters were strong had higher offspring survival than females whose bonds with these relatives were weak."
Silk's past research with Jeanne Altmann, the Eugene Higgins Professor of Ecology and Evolutionary Biology at Princeton University, and Susan C. Alberts, a professor of biology at Duke University, on baboons in the Amboseli Basin of Kenya had found a higher survival rate for baboons with social mothers, but the research only tracked offspring through the first year of life.
For the new study, researchers followed offspring from 1 year of age through sexual maturity — roughly 5 years of age. The new study also differs from past baboon research by focusing on the strength and duration of relationships between pairs of females rather than on the amount of social interactions in general.
"The benefit comes not from being wildly social — it's about having close social bonds," said Cheney, who runs the Moremi baboon-tracking project with University of Pennsylvania psychology professor Robert M. Seyfarth.
"These females form strong relationships with particular partners," Silk said. "They don't treat everyone the same. They spend a lot more time with — and a lot more time grooming — some females than others, and these relationships tend to be very long-lasting."
Additional research is needed to determine how the female bonds improve infant survival, but it may have to do with such stress hormones as cortisol, Silk said. Research has shown that prolonged elevations of stress hormones in primates can lead to cardiovascular disease and other serious health problems. Research has also shown that grooming tends to lower these stress hormones in baboons.
"Our research suggests that somehow there is a link between the kind of social relationships you form and the natural, normal stresses that occur in everyday life, and that seems to have — at least in baboons — a long-term effect on reproductive success," Silk said.
Said to share 92 percent of their DNA with humans, baboons are close relatives of humans. Baboons and humans last shared a common ancestor about 18 million years ago. The new findings on social interactions among mothers parallel recent research that has shown health benefits for humans who enjoy particularly close social networks.
"Our findings suggest benefits from forming close relationships are built into us from a long way back," Silk said.
The research received funding from the National Geographic Foundation, the Research Foundation of the University of Pennsylvania, the Institute for Research in Cognitive Science at the University of Pennsylvania, the National Institute of Health and the National Science Foundation.
Wednesday, June 3, 2009
Feeling Close To A Friend Increases Progesterone, Boosts Well-being And Reduces Anxiety And Stress
http://www.sciencedaily.com/releases/2009/06/090602171941.htm
ScienceDaily (June 3, 2009) — Why does dishing with a girlfriend do wonders for a woman's mood?
A University of Michigan study has identified a likely reason: feeling emotionally close to a friend increases levels of the hormone progesterone, helping to boost well-being and reduce anxiety and stress.
"This study establishes progesterone as a likely part of the neuroendocrine basis of social bonding in humans," said U-M researcher Stephanie Brown, lead author of an article reporting the study findings, published in the current (June 2009) issue of the peer-reviewed journal Hormones and Behavior.
A sex hormone that fluctuates with the menstrual cycle, progesterone is also present in low levels in post-menopausal women and in men. Earlier research has shown that higher levels of progesterone increase the desire to bond with others, but the current study is the first to show that bonding with others increases levels of progesterone. The study also links these increases to a greater willingness to help other people, even at our own expense.
"It's important to find the links between biological mechanisms and human social behavior," said Brown, is a faculty associate at the U-M Institute for Social Research (ISR) and an assistant professor of internal medicine at the U-M Medical School. She is also affiliated with the Ann Arbor Veterans Affairs Hospital. "These links may help us understand why people in close relationships are happier, healthier, and live longer than those who are socially isolated."
Progesterone is much easier to measure than oxytocin, a hormone linked to trust, pair-bonding and maternal responsiveness in humans and other mammals. Oxytocin can only be measured through an invasive spinal tap or through expensive and complex brain imaging methods, such as positron emission tomography scans. Progesterone can be measured through simple saliva samples and may be related to oxytocin.
In the current study, Brown and colleagues examined the link between interpersonal closeness and salivary progesterone in 160 female college students.
At the start of the study, the researchers measured the levels of progesterone and of the stress hormone cortisol in the women's saliva, and obtained information about their menstrual cycles and whether they were using hormonal contraceptives or other hormonally active medications.
To control for daily variations in hormone levels, all the sessions were held between noon and 7 p.m.
The women were randomly assigned to partners and asked to perform either a task designed to elicit feelings of emotional closeness or a task that was emotionally neutral.
In the emotionally neutral task, the women proofread a botany manuscript together.
After completing the 20-minute tasks, the women played a computerized cooperative card game with their partners, and then had their progesterone and cortisol sampled again.
The progesterone levels of women who had engaged in the emotionally neutral tasks tended to decline, while the progesterone levels of women who engaged in the task designed to elicit closeness either remained the same or increased. The participants' cortisol levels did not change in a similar way.
Participants returned a week later, and played the computerized card game with their original partners again. Then researchers measured their progesterone and cortisol. Researchers also examined links between progesterone levels and how likely participants said they would be to risk their life for their partner.
"During the first phase of the study, we found no evidence of a relationship between progesterone and willingness to sacrifice," Brown said. "But a week later, increased progesterone predicted an increased willingness to say you would risk your life to help your partner."
According to Brown, the findings are consistent with a new evolutionary theory of altruism which argues that the hormonal basis of social bonds enables people to suppress self-interest when necessary in order to promote the well-being of another person, as when taking care of children or helping ailing family members or friends.
The results also help explain why social contact has well-documented health benefits---a relationship first identified nearly 20 years ago by U-M sociologist James House.
"Many of the hormones involved in bonding and helping behavior lead to reductions in stress and anxiety in both humans and other animals. Now we see that higher levels of progesterone may be part of the underlying physiological basis for these effects," Brown said.
ScienceDaily (June 3, 2009) — Why does dishing with a girlfriend do wonders for a woman's mood?
A University of Michigan study has identified a likely reason: feeling emotionally close to a friend increases levels of the hormone progesterone, helping to boost well-being and reduce anxiety and stress.
"This study establishes progesterone as a likely part of the neuroendocrine basis of social bonding in humans," said U-M researcher Stephanie Brown, lead author of an article reporting the study findings, published in the current (June 2009) issue of the peer-reviewed journal Hormones and Behavior.
A sex hormone that fluctuates with the menstrual cycle, progesterone is also present in low levels in post-menopausal women and in men. Earlier research has shown that higher levels of progesterone increase the desire to bond with others, but the current study is the first to show that bonding with others increases levels of progesterone. The study also links these increases to a greater willingness to help other people, even at our own expense.
"It's important to find the links between biological mechanisms and human social behavior," said Brown, is a faculty associate at the U-M Institute for Social Research (ISR) and an assistant professor of internal medicine at the U-M Medical School. She is also affiliated with the Ann Arbor Veterans Affairs Hospital. "These links may help us understand why people in close relationships are happier, healthier, and live longer than those who are socially isolated."
Progesterone is much easier to measure than oxytocin, a hormone linked to trust, pair-bonding and maternal responsiveness in humans and other mammals. Oxytocin can only be measured through an invasive spinal tap or through expensive and complex brain imaging methods, such as positron emission tomography scans. Progesterone can be measured through simple saliva samples and may be related to oxytocin.
In the current study, Brown and colleagues examined the link between interpersonal closeness and salivary progesterone in 160 female college students.
At the start of the study, the researchers measured the levels of progesterone and of the stress hormone cortisol in the women's saliva, and obtained information about their menstrual cycles and whether they were using hormonal contraceptives or other hormonally active medications.
To control for daily variations in hormone levels, all the sessions were held between noon and 7 p.m.
The women were randomly assigned to partners and asked to perform either a task designed to elicit feelings of emotional closeness or a task that was emotionally neutral.
In the emotionally neutral task, the women proofread a botany manuscript together.
After completing the 20-minute tasks, the women played a computerized cooperative card game with their partners, and then had their progesterone and cortisol sampled again.
The progesterone levels of women who had engaged in the emotionally neutral tasks tended to decline, while the progesterone levels of women who engaged in the task designed to elicit closeness either remained the same or increased. The participants' cortisol levels did not change in a similar way.
Participants returned a week later, and played the computerized card game with their original partners again. Then researchers measured their progesterone and cortisol. Researchers also examined links between progesterone levels and how likely participants said they would be to risk their life for their partner.
"During the first phase of the study, we found no evidence of a relationship between progesterone and willingness to sacrifice," Brown said. "But a week later, increased progesterone predicted an increased willingness to say you would risk your life to help your partner."
According to Brown, the findings are consistent with a new evolutionary theory of altruism which argues that the hormonal basis of social bonds enables people to suppress self-interest when necessary in order to promote the well-being of another person, as when taking care of children or helping ailing family members or friends.
The results also help explain why social contact has well-documented health benefits---a relationship first identified nearly 20 years ago by U-M sociologist James House.
"Many of the hormones involved in bonding and helping behavior lead to reductions in stress and anxiety in both humans and other animals. Now we see that higher levels of progesterone may be part of the underlying physiological basis for these effects," Brown said.
Sexual Partner Status Affects A Woman's, But Not A Man's, Interest In The Opposite Sex
http://www.sciencedaily.com/releases/2009/05/090528120657.htm ScienceDaily (June 3, 2009) — A study by Indiana University neuroscientist Heather Rupp found that a woman's partner status influenced her interest in the opposite sex. In the study, women both with and without sexual partners showed little difference in their subjective ratings of photos of men when considering such measures as masculinity and attractiveness. However, the women who did not have sexual partners spent more time evaluating photos of men, demonstrating a greater interest in the photos.
No such difference was found between men who had sexual partners and those who did not. "These findings may reflect sex differences in reproductive strategies that may act early in the cognitive processing of potential partners and contribute to sex differences in sexual attraction and behavior," said Rupp, assistant scientist at The Kinsey Institute for Research in Sex, Gender and Reproduction.
For the study, 59 men and 56 women rated 510 photos of opposite-sex faces for realism, masculinity/femininity, attractiveness, or affect. Participants were instructed to give their "gut" reaction and to rate the pictures as quickly as possible. The men and women ranged in age from 17 to 26, were heterosexual, from a variety of ethnic backgrounds and were not using hormonal contraception. Of the women, 21 reported they had a current sexual partner; 25 of the men reported having a sexual partner. This is the first study to report whether having a current sexual partner influences interest in the opposite sex. Other studies have demonstrated that hormones, relationship goals and social context influence such interest.
"That there were no detectable effects of sexual partner status on women's subjective ratings of male faces, but there were on response times, which emphasizes the subtlety of this effect and introduces the possibility that sexual partner status impacts women's cognitive processing of novel male faces but not necessarily their conscious subjective appraisal," the authors wrote in the journal article. The researchers also note that influence of partner status in women could reflect that women, on average, are relatively committed in their romantic relationships, "which possibly suppresses their attention to and appraisal of alternative partners."
No such difference was found between men who had sexual partners and those who did not. "These findings may reflect sex differences in reproductive strategies that may act early in the cognitive processing of potential partners and contribute to sex differences in sexual attraction and behavior," said Rupp, assistant scientist at The Kinsey Institute for Research in Sex, Gender and Reproduction.
For the study, 59 men and 56 women rated 510 photos of opposite-sex faces for realism, masculinity/femininity, attractiveness, or affect. Participants were instructed to give their "gut" reaction and to rate the pictures as quickly as possible. The men and women ranged in age from 17 to 26, were heterosexual, from a variety of ethnic backgrounds and were not using hormonal contraception. Of the women, 21 reported they had a current sexual partner; 25 of the men reported having a sexual partner. This is the first study to report whether having a current sexual partner influences interest in the opposite sex. Other studies have demonstrated that hormones, relationship goals and social context influence such interest.
"That there were no detectable effects of sexual partner status on women's subjective ratings of male faces, but there were on response times, which emphasizes the subtlety of this effect and introduces the possibility that sexual partner status impacts women's cognitive processing of novel male faces but not necessarily their conscious subjective appraisal," the authors wrote in the journal article. The researchers also note that influence of partner status in women could reflect that women, on average, are relatively committed in their romantic relationships, "which possibly suppresses their attention to and appraisal of alternative partners."
Orangutans Communicate As If They Were Playing Charades
http://www.sciencedaily.com/releases/2007/08/070802091437.htm
ScienceDaily (Aug. 2, 2007) — When using gestures to get their points across, orangutans rely on the same basic strategy that humans follow when playing the popular game and intentionally modify or repeat hand (or other) signals based on the success or failure of their first attempt.
Professor Richard Byrne of the School of Psychology said, "We were surprised that the orangutans' responses so clearly signaled their assessment of the audience's comprehension. Looking at the tapes of the animal's responses, you can easily work out whether the orangutan thinks it has been fully, partially, or not understood, without seeing what went before."
"This means that, in effect, they are passing information back to the audience about how well they are doing in understanding them, hence our 'charades' analogy. In playing the game, you want primarily to convey your meaning non-verbally - as does the orangutan - but secondarily to help the team get your meaning by giving them hints as to how well they are doing."
To find out whether orangutans intentionally communicate with people through gestures - a skill earlier attributed to chimpanzees - PhD student Erica Cartmill and Professor Byrne presented six orangutans in Jersey and Twycross Zoos with situations in which one tempting and one not-so-tempting food item had to be reached with human help.
But to test the orangutans' strategy, there was a catch. Rather than play along all the time, the experimenter sometimes purposefully misunderstood the orangutan's requests, providing them with only half of the delicious treat in some cases and, in others, handing over the less pleasant alternative instead.
When the person they were trying to communicate with did not meet orangutans' aims, they persisted with further attempts, the researchers reported. When partially understood, the animals narrowed down their range of signals, focusing on gestures already used and repeating them frequently. In contrast, when completely misunderstood, orangutans elaborated their range of gestures, avoiding repetition of 'failed' signals.
"The response showed that the orangutan had intended a particular result, anticipated getting it, and kept trying until it got the result," Cartmill said. "The orangutans made a clear distinction between total misunderstanding, when they tended to give up on the signals they'd used already, and use new, but equivalent, ones to get the idea across, and partial misunderstanding, when they tended to repeat the signals that had already partially worked, keeping at it with vigor. The result was that understanding could be achieved more quickly."
The orangutans' charades-like strategy is one way to construct shared meaning from learned or ritualised signals in the absence of language, the researchers concluded. Further investigation of communication among apes may therefore provide insight into the pre-linguistic devices that helped construct the very earliest forms of hominid language.
The findings are published in Current Biology (2 August 2007).
ScienceDaily (Aug. 2, 2007) — When using gestures to get their points across, orangutans rely on the same basic strategy that humans follow when playing the popular game and intentionally modify or repeat hand (or other) signals based on the success or failure of their first attempt.
Professor Richard Byrne of the School of Psychology said, "We were surprised that the orangutans' responses so clearly signaled their assessment of the audience's comprehension. Looking at the tapes of the animal's responses, you can easily work out whether the orangutan thinks it has been fully, partially, or not understood, without seeing what went before."
"This means that, in effect, they are passing information back to the audience about how well they are doing in understanding them, hence our 'charades' analogy. In playing the game, you want primarily to convey your meaning non-verbally - as does the orangutan - but secondarily to help the team get your meaning by giving them hints as to how well they are doing."
To find out whether orangutans intentionally communicate with people through gestures - a skill earlier attributed to chimpanzees - PhD student Erica Cartmill and Professor Byrne presented six orangutans in Jersey and Twycross Zoos with situations in which one tempting and one not-so-tempting food item had to be reached with human help.
But to test the orangutans' strategy, there was a catch. Rather than play along all the time, the experimenter sometimes purposefully misunderstood the orangutan's requests, providing them with only half of the delicious treat in some cases and, in others, handing over the less pleasant alternative instead.
When the person they were trying to communicate with did not meet orangutans' aims, they persisted with further attempts, the researchers reported. When partially understood, the animals narrowed down their range of signals, focusing on gestures already used and repeating them frequently. In contrast, when completely misunderstood, orangutans elaborated their range of gestures, avoiding repetition of 'failed' signals.
"The response showed that the orangutan had intended a particular result, anticipated getting it, and kept trying until it got the result," Cartmill said. "The orangutans made a clear distinction between total misunderstanding, when they tended to give up on the signals they'd used already, and use new, but equivalent, ones to get the idea across, and partial misunderstanding, when they tended to repeat the signals that had already partially worked, keeping at it with vigor. The result was that understanding could be achieved more quickly."
The orangutans' charades-like strategy is one way to construct shared meaning from learned or ritualised signals in the absence of language, the researchers concluded. Further investigation of communication among apes may therefore provide insight into the pre-linguistic devices that helped construct the very earliest forms of hominid language.
The findings are published in Current Biology (2 August 2007).
Friday, May 29, 2009
Male Or Female? Coloring Provides Gender Cues
http://www.sciencedaily.com/releases/2009/05/090527121049.htm
ScienceDaily (May 28, 2009) — Our brain is wired to identify gender based on facial cues and coloring, according to a new study published in the Journal of Vision. Psychology Professor Frédéric Gosselin and his Université de Montréal team found the luminescence of the eyebrow and mouth region is vital in rapid gender discrimination.
"As teenagers, dimorphism (systematic difference between sexes) increases in the nose, chin, mouth, jaw, eyes and general shape of faces," says Nicolas Dupuis-Roy, lead author of the study. "Yet we aren't conscious of how our brain recognizes those differences."
To discover those reference points, Dupuis-Roy and colleagues showed photos of 300 Caucasian faces to some 30 participants. Subjects were asked to identify gender based on images where parts of faces were concealed using a technology called Bubbles.
The investigation found that eyes and mouths, specifically their subtle shading or luminance, are paramount in identifying gender. Unlike previous studies, which found the gap between the eyelid and eyebrow as essential in gender ID, this investigation found the shades of reds and greens around mouths and eyes led to faster gender discrimination.
"Studies have shown that an androgynous face is considered male if the skin complexion is redder, and considered female if the complexion is greener," says Dupuis-Roy. "However, it is the opposite for the mouth. A woman's mouth is usually redder. Our brain interprets this characteristic as female."
"A man's face usually reflects less light around the eyebrows. This is because they are usually thicker. The same applies to the upper lip and chin, which are hairier areas," he adds, noting people clearly use colour to rapidly identify gender.
This research was supported by the Fonds québécois de la recherche sur la nature et les technologies and Natural Sciences and Engineering Research Council of Canada. PhD student Isabelle Fortin and Professor Daniel Fiset also participated in the study.
ScienceDaily (May 28, 2009) — Our brain is wired to identify gender based on facial cues and coloring, according to a new study published in the Journal of Vision. Psychology Professor Frédéric Gosselin and his Université de Montréal team found the luminescence of the eyebrow and mouth region is vital in rapid gender discrimination.
"As teenagers, dimorphism (systematic difference between sexes) increases in the nose, chin, mouth, jaw, eyes and general shape of faces," says Nicolas Dupuis-Roy, lead author of the study. "Yet we aren't conscious of how our brain recognizes those differences."
To discover those reference points, Dupuis-Roy and colleagues showed photos of 300 Caucasian faces to some 30 participants. Subjects were asked to identify gender based on images where parts of faces were concealed using a technology called Bubbles.
The investigation found that eyes and mouths, specifically their subtle shading or luminance, are paramount in identifying gender. Unlike previous studies, which found the gap between the eyelid and eyebrow as essential in gender ID, this investigation found the shades of reds and greens around mouths and eyes led to faster gender discrimination.
"Studies have shown that an androgynous face is considered male if the skin complexion is redder, and considered female if the complexion is greener," says Dupuis-Roy. "However, it is the opposite for the mouth. A woman's mouth is usually redder. Our brain interprets this characteristic as female."
"A man's face usually reflects less light around the eyebrows. This is because they are usually thicker. The same applies to the upper lip and chin, which are hairier areas," he adds, noting people clearly use colour to rapidly identify gender.
This research was supported by the Fonds québécois de la recherche sur la nature et les technologies and Natural Sciences and Engineering Research Council of Canada. PhD student Isabelle Fortin and Professor Daniel Fiset also participated in the study.
Wednesday, May 27, 2009
Some People Really 'Never Forget A Face:' Understanding Extraordinary Face Recognition Ability
http://www.sciencedaily.com/releases/2009/05/090519172204.htm
ScienceDaily (May 20, 2009) — Some people say they never forget a face, a claim now bolstered by psychologists at Harvard University who've discovered a group they call "super-recognizers": those who can easily recognize someone they met in passing, even many years later.
The new study suggests that skill in facial recognition might vary widely among humans. Previous research has identified as much as 2 percent of the population as having "face-blindness," or prosopagnosia, a condition characterized by great difficulty in recognizing faces. For the first time, this new research shows that others excel in face recognition, indicating that the trait could be on a spectrum, with prosopagnosics on the low end and super-recognizers at the high end.
The research is published in Psychonomic Bulletin & Review, and was led by Richard Russell, a postdoctoral researcher in the Department of Psychology at Harvard, with co-authors Ken Nakayama, Edgar Pierce Professor of Psychology at Harvard, and Brad Duchaine of the University College London.
The research involved administering standardized face recognition tests. The super-recognizers scored far above average on these tests—higher than any of the normal control subjects.
"There has been a default assumption that there is either normal face recognition, or there is disordered face recognition," says Russell. "This suggests that's not the case, that there is actually a very wide range of ability. It suggests a different model—a different way of thinking about face recognition ability, and possibly even other aspects of perception, in terms of a spectrum of abilities, rather than there being normal and disordered ability."
Super-recognizers report that they recognize other people far more often than they are recognized. For this reason, says Russell, they often compensate by pretending not to recognize someone they met in passing, so as to avoid appearing to attribute undue importance to a fleeting encounter.
"Super-recognizers have these extreme stories of recognizing people," says Russell. "They recognize a person who was shopping in the same store with them two months ago, for example, even if they didn't speak to the person. It doesn't have to be a significant interaction; they really stand out in terms of their ability to remember the people who were actually less significant."
One woman in the study said she had identified another woman on the street who served as her as a waitress five years earlier in a different city. Critically, she was able to confirm that the other woman had in fact been a waitress in the different city. Often, super-recognizers are able to recognize another person despite significant changes in appearance, such as aging or a different hair color.
If face recognition abilities do vary, testing for this may be important for assessing eyewitness testimony, or for interviewing for some jobs, such as security or those checking identification.
Russell theorizes that super-recognizers and those with face-blindness may only be distinguishable today because our communities differ from how they existed thousands of years ago.
"Until recently, most humans lived in much smaller communities, with many fewer people interacting on a regular basis within a group," says Russell. "It may be a fairly new phenomenon that there's even a need to recognize large numbers of people."
The research was funded by the U.S. National Eye Institute and the U.K. Economic and Social Research Council
Interesting, a new ability based on our current living situations and not our past ones. I can see how this wouldn't be beneficial in the past with exposure to such few people, and why it would be favored in our current situation.
ScienceDaily (May 20, 2009) — Some people say they never forget a face, a claim now bolstered by psychologists at Harvard University who've discovered a group they call "super-recognizers": those who can easily recognize someone they met in passing, even many years later.
The new study suggests that skill in facial recognition might vary widely among humans. Previous research has identified as much as 2 percent of the population as having "face-blindness," or prosopagnosia, a condition characterized by great difficulty in recognizing faces. For the first time, this new research shows that others excel in face recognition, indicating that the trait could be on a spectrum, with prosopagnosics on the low end and super-recognizers at the high end.
The research is published in Psychonomic Bulletin & Review, and was led by Richard Russell, a postdoctoral researcher in the Department of Psychology at Harvard, with co-authors Ken Nakayama, Edgar Pierce Professor of Psychology at Harvard, and Brad Duchaine of the University College London.
The research involved administering standardized face recognition tests. The super-recognizers scored far above average on these tests—higher than any of the normal control subjects.
"There has been a default assumption that there is either normal face recognition, or there is disordered face recognition," says Russell. "This suggests that's not the case, that there is actually a very wide range of ability. It suggests a different model—a different way of thinking about face recognition ability, and possibly even other aspects of perception, in terms of a spectrum of abilities, rather than there being normal and disordered ability."
Super-recognizers report that they recognize other people far more often than they are recognized. For this reason, says Russell, they often compensate by pretending not to recognize someone they met in passing, so as to avoid appearing to attribute undue importance to a fleeting encounter.
"Super-recognizers have these extreme stories of recognizing people," says Russell. "They recognize a person who was shopping in the same store with them two months ago, for example, even if they didn't speak to the person. It doesn't have to be a significant interaction; they really stand out in terms of their ability to remember the people who were actually less significant."
One woman in the study said she had identified another woman on the street who served as her as a waitress five years earlier in a different city. Critically, she was able to confirm that the other woman had in fact been a waitress in the different city. Often, super-recognizers are able to recognize another person despite significant changes in appearance, such as aging or a different hair color.
If face recognition abilities do vary, testing for this may be important for assessing eyewitness testimony, or for interviewing for some jobs, such as security or those checking identification.
Russell theorizes that super-recognizers and those with face-blindness may only be distinguishable today because our communities differ from how they existed thousands of years ago.
"Until recently, most humans lived in much smaller communities, with many fewer people interacting on a regular basis within a group," says Russell. "It may be a fairly new phenomenon that there's even a need to recognize large numbers of people."
The research was funded by the U.S. National Eye Institute and the U.K. Economic and Social Research Council
Interesting, a new ability based on our current living situations and not our past ones. I can see how this wouldn't be beneficial in the past with exposure to such few people, and why it would be favored in our current situation.
Rich Man, Poor Man: Body Language Can Indicate Socioeconomic Status, Study Shows
http://www.sciencedaily.com/releases/2009/02/090204121515.htm
ScienceDaily (Feb. 5, 2009) — Socioeconomic status (SES) is determined by a number of factors such as wealth, occupation and schools attended. SES influences the food we eat, hobbies we participate in and can even have an impact on our health.
People with an upper SES background can often be accused of flaunting their status, such as by the types of cars they drive or how many pairs of Manolo Blahniks they have in their closet. It is easy to guess someone's SES based on their clothing and the size of their home, but what about more subtle clues? Psychologists Michael W. Kraus and Dacher Keltner of the University of California, Berkeley wanted to see if non-verbal cues (that is, body language) can indicate our SES.
To test this idea, the researchers videotaped participants as they got to know one another in one-on-one interview sessions. During these taped sessions, the researchers looked for two types of behaviors: disengagement behaviors (including fidgeting with personal objects and doodling) and engagement behaviors (including head nodding, laughing and eye contact).
The results, reported in Psychological Science, reveal that nonverbal cues can give away a person's SES. Volunteers whose parents were from upper SES backgrounds displayed more disengagement-related behaviors compared to participants from lower SES backgrounds. In addition, when a separate group of observers were shown 60 second clips of the videos, they were able to correctly guess the participants' SES background, based on their body language.
The researchers note that this is the first study to show a relation between SES and social engagement behavior. They surmise that people from upper SES backgrounds who are wealthy and have access to prestigious institutions tend to be less dependent on others. "This lack of dependence among upper SES people is displayed in their nonverbal behaviors during social interactions," the psychologists conclude.
Journal reference:
Kraus et al. Signs of Socioeconomic Status: A Thin-Slicing Approach. Psychological Science, 2009; 20 (1): 99 DOI: 10.1111/j.1467-9280.2008.02251.x
I think it's not only interesting that we unconsciously (maybe even consciously) portray our SES by body language, but that the participants were able to correctly identify their standing with 100 percent accuracy. I can see how it would be beneficial to show a wealthy status but to also evolve to pick up on those cues. Also their conclusion makes a lot of sense as well, why would you need to keep broadening your social circle if you don't need more support? It's actually probably a hindrance to keep attracting more people who may need your resources. I can see the good side and bad side of advertising your SES, and this study helps support the idea that it's more beneficial to display it.
ScienceDaily (Feb. 5, 2009) — Socioeconomic status (SES) is determined by a number of factors such as wealth, occupation and schools attended. SES influences the food we eat, hobbies we participate in and can even have an impact on our health.
People with an upper SES background can often be accused of flaunting their status, such as by the types of cars they drive or how many pairs of Manolo Blahniks they have in their closet. It is easy to guess someone's SES based on their clothing and the size of their home, but what about more subtle clues? Psychologists Michael W. Kraus and Dacher Keltner of the University of California, Berkeley wanted to see if non-verbal cues (that is, body language) can indicate our SES.
To test this idea, the researchers videotaped participants as they got to know one another in one-on-one interview sessions. During these taped sessions, the researchers looked for two types of behaviors: disengagement behaviors (including fidgeting with personal objects and doodling) and engagement behaviors (including head nodding, laughing and eye contact).
The results, reported in Psychological Science, reveal that nonverbal cues can give away a person's SES. Volunteers whose parents were from upper SES backgrounds displayed more disengagement-related behaviors compared to participants from lower SES backgrounds. In addition, when a separate group of observers were shown 60 second clips of the videos, they were able to correctly guess the participants' SES background, based on their body language.
The researchers note that this is the first study to show a relation between SES and social engagement behavior. They surmise that people from upper SES backgrounds who are wealthy and have access to prestigious institutions tend to be less dependent on others. "This lack of dependence among upper SES people is displayed in their nonverbal behaviors during social interactions," the psychologists conclude.
Journal reference:
Kraus et al. Signs of Socioeconomic Status: A Thin-Slicing Approach. Psychological Science, 2009; 20 (1): 99 DOI: 10.1111/j.1467-9280.2008.02251.x
I think it's not only interesting that we unconsciously (maybe even consciously) portray our SES by body language, but that the participants were able to correctly identify their standing with 100 percent accuracy. I can see how it would be beneficial to show a wealthy status but to also evolve to pick up on those cues. Also their conclusion makes a lot of sense as well, why would you need to keep broadening your social circle if you don't need more support? It's actually probably a hindrance to keep attracting more people who may need your resources. I can see the good side and bad side of advertising your SES, and this study helps support the idea that it's more beneficial to display it.
Psychologists Find That Head Movement Is More Important Than Gender In Nonverbal Communication
http://www.sciencedaily.com/releases/2009/05/090525105459.htm
ScienceDaily (May 26, 2009) — It is well known that people use head motion during conversation to convey a range of meanings and emotions, and that women use more active head motion when conversing with each other than men use when they talk with each other.
When men and women converse together, the men use a little more head motion and the women use a little less. But the men and women might be adapting because of their gender-based expectations or because of the movements they perceive from each other.
What would happen if you could change the apparent gender of a conversant while keeping all of the motion dynamics of head movement and facial expression?
Using new videoconferencing technology, a team of psychologists and computer scientists – led by Steven Boker, a professor of psychology at the University of Virginia – were able to switch the apparent gender of study participants during conversation and found that head motion was more important than gender in determining how people coordinate with each other while engaging in conversation.
The scientists found that gender-based social expectations are unlikely to be the source of reported gender differences in the way people coordinate their head movements during two-way conversation.
The researchers used synthesized faces – known as avatars – in video-conferences with naïve participants, who believed they were conversing onscreen with an actual person rather than a synthetic version of a person.
In some conversations, the researchers changed the gender of the avatars and the vocal pitch of the avatar's voice – while still maintaining their actual head movements and facial expressions – convincing naïve participants that they were speaking with, for example, a male when they were in fact speaking with a female, or vice versa.
"We found that people simply adapt to each other's head movements and facial expressions, regardless of the apparent sex of the person they are talking to," Boker said. "This is important because it indicates that how you appear is less important than how you move when it comes to what other people feel when they speak with you."
He presented the findings May 24 at the annual convention of the Association for Psychological Science in San Francisco. A paper detailing the results is scheduled for publication in the Journal of Experimental Psychology: Human Perception and Performance.
The study, funded by the National Science Foundation, used a low-bandwidth, high-frame-rate videoconferencing technology to record and recreate facial expressions to see how people alter their behavior based on the slightest changes in expression of another person. The U.Va.-based team also includes researchers at the University of Pittsburgh, University of East Anglia, Carnegie Mellon University and Disney Research.
A video demonstration is available online at: http://faculty.virginia.edu/humandynamicslab/.
The technology uses statistical representations of a person's face to track and reconstruct that face. This allows the principal components of facial expression – only dozens in number – to be transmitted as a close rendition of the actual face. It's a sort of connect-the-dots fabrication that can be transmitted frame by frame in near-real time.
Boker and his team are trying to understand how people interact during conversation, and how factors such as gender or race may alter the dynamics of a conversation. To do so, they needed a way to capture facial expressions people use when conversing.
"From a psychological standpoint, our interest is in how people interact and how they coordinate their facial expressions as they talk with one another, such as when one person nods while speaking, or listening, the other person likewise nods," Boker said.
It is this "mirroring process" of coordination that helps people to feel a connection with each other.
"When I coordinate my facial expressions or head movements with yours, I activate a system that helps me empathize with your feelings," Boker said.
The technology the team developed further allows them to map the facial expressions of one person onto the face of another in a real time videoconference. In this way they can change the apparent gender or race of a participant and closely track how a naïve participant reacts when speaking to a woman, say, as opposed to a man.
"In this way we can distinguish between how people coordinate their facial expressions and what their social expectation is," Boker said.
This is absolutely amazing to me that we are so intuned to head motion that we can be tricked into perceiving another gender. I guess this exists because the more intuned you are the better your social relations are and therfore are more likely to survive.
ScienceDaily (May 26, 2009) — It is well known that people use head motion during conversation to convey a range of meanings and emotions, and that women use more active head motion when conversing with each other than men use when they talk with each other.
When men and women converse together, the men use a little more head motion and the women use a little less. But the men and women might be adapting because of their gender-based expectations or because of the movements they perceive from each other.
What would happen if you could change the apparent gender of a conversant while keeping all of the motion dynamics of head movement and facial expression?
Using new videoconferencing technology, a team of psychologists and computer scientists – led by Steven Boker, a professor of psychology at the University of Virginia – were able to switch the apparent gender of study participants during conversation and found that head motion was more important than gender in determining how people coordinate with each other while engaging in conversation.
The scientists found that gender-based social expectations are unlikely to be the source of reported gender differences in the way people coordinate their head movements during two-way conversation.
The researchers used synthesized faces – known as avatars – in video-conferences with naïve participants, who believed they were conversing onscreen with an actual person rather than a synthetic version of a person.
In some conversations, the researchers changed the gender of the avatars and the vocal pitch of the avatar's voice – while still maintaining their actual head movements and facial expressions – convincing naïve participants that they were speaking with, for example, a male when they were in fact speaking with a female, or vice versa.
"We found that people simply adapt to each other's head movements and facial expressions, regardless of the apparent sex of the person they are talking to," Boker said. "This is important because it indicates that how you appear is less important than how you move when it comes to what other people feel when they speak with you."
He presented the findings May 24 at the annual convention of the Association for Psychological Science in San Francisco. A paper detailing the results is scheduled for publication in the Journal of Experimental Psychology: Human Perception and Performance.
The study, funded by the National Science Foundation, used a low-bandwidth, high-frame-rate videoconferencing technology to record and recreate facial expressions to see how people alter their behavior based on the slightest changes in expression of another person. The U.Va.-based team also includes researchers at the University of Pittsburgh, University of East Anglia, Carnegie Mellon University and Disney Research.
A video demonstration is available online at: http://faculty.virginia.edu/humandynamicslab/.
The technology uses statistical representations of a person's face to track and reconstruct that face. This allows the principal components of facial expression – only dozens in number – to be transmitted as a close rendition of the actual face. It's a sort of connect-the-dots fabrication that can be transmitted frame by frame in near-real time.
Boker and his team are trying to understand how people interact during conversation, and how factors such as gender or race may alter the dynamics of a conversation. To do so, they needed a way to capture facial expressions people use when conversing.
"From a psychological standpoint, our interest is in how people interact and how they coordinate their facial expressions as they talk with one another, such as when one person nods while speaking, or listening, the other person likewise nods," Boker said.
It is this "mirroring process" of coordination that helps people to feel a connection with each other.
"When I coordinate my facial expressions or head movements with yours, I activate a system that helps me empathize with your feelings," Boker said.
The technology the team developed further allows them to map the facial expressions of one person onto the face of another in a real time videoconference. In this way they can change the apparent gender or race of a participant and closely track how a naïve participant reacts when speaking to a woman, say, as opposed to a man.
"In this way we can distinguish between how people coordinate their facial expressions and what their social expectation is," Boker said.
This is absolutely amazing to me that we are so intuned to head motion that we can be tricked into perceiving another gender. I guess this exists because the more intuned you are the better your social relations are and therfore are more likely to survive.
Want to Live Longer? Stop Worrying
http://news.nationalgeographic.com/news/2009/04/090410-live-longer-neurotic.html
Christine Dell'AmoreNational Geographic News
April 10, 2009
If you want to live to a hundred, you'd better lighten up.
Children of centenarians—who usually inherit both longevity and personality traits from their parents—are on average more outgoing, agreeable, and less neurotic, according to a new study.
That's because being affable and more social confers health benefits, according to lead study author Thomas Perls, director of the New England Centenarian Study at Boston University Medical Center.
It may be that less neurotic people are better able to manage or regulate stressful situations than the highly neurotic, Perls said.
"We've seen centenarians go through huge amounts of stress, and time and time again they've shown us how … it doesn't get to them."
Likable People
The Boston University team gave 246 unrelated children of centenarians a questionnaire that measures neuroticism, extraversion, openness, agreeableness, and conscientiousness.
Rather than directly testing the elderly, the team looked at both male and female offspring who had an average age of 75.
"They're at the stage of their lives when they're cooking along at 110 percent," Perls said. "There's a number of things we can study in them that we can't" in centenarians.
Both males and females scored in the low range for being neurotic and the high range for being extroverted.
Women scored high in agreeableness, while men scored normal. Both sexes tested normal for conscientiousness and openness, according to the study, published in the April issue of the Journal of the American Geriatrics Society.
Buettner has not studied the children of centenarians, though that methodology is "absolutely" valid, he said.
(Buettner has also received funding from the National Geographic Society, which owns National Geographic News.)
In the blue zone of Okinawa, Japan, Buettner asked expert Nobuyoshi Hirose what he thought explains Okinawans' longevity.
"He thought for a moment, and said, They're likable people," Buettner said.
That likeability translates to a robust social circle, one of the common threads among the long-lived, Buettner added.
Improvements
Though many aspects of our personalities are already set by our genes, Buettner said, we can all make lifestyle improvements to help us live longer.
For one, becoming more extroverted—and by extension widening our social networks—can be cultivated and trained, Buettner said.
Also high on his list is eating a plant-based diet—"the more meat you eat, the quicker you die," he said.
And having a clear sense of purpose in your life, he added, is worth seven years of life expectancy.
Study leader Perls added that numerous strategies exist to deal with stress, such as exercising, meditation, or just taking a "nice deep breath."
"It's a matter of setting aside the time and effort to effectively manage your stress well," he said. "One of the keys is to realize how important it is to do that."
While this study does support the theory we were meant to eat a plant based diet, the advice to stop worrying seemed opposite of what I would think to expect. Caution usually equals you spread your genes, but I think this is suggeting that the worrying gets in the way of broadening social networds.
What is it about a large social network that evolution psychology would say extends someone's life? My guesses are resources, support during rough times, a feeling of belonging, or protection from enemies.
Christine Dell'AmoreNational Geographic News
April 10, 2009
If you want to live to a hundred, you'd better lighten up.
Children of centenarians—who usually inherit both longevity and personality traits from their parents—are on average more outgoing, agreeable, and less neurotic, according to a new study.
That's because being affable and more social confers health benefits, according to lead study author Thomas Perls, director of the New England Centenarian Study at Boston University Medical Center.
It may be that less neurotic people are better able to manage or regulate stressful situations than the highly neurotic, Perls said.
"We've seen centenarians go through huge amounts of stress, and time and time again they've shown us how … it doesn't get to them."
Likable People
The Boston University team gave 246 unrelated children of centenarians a questionnaire that measures neuroticism, extraversion, openness, agreeableness, and conscientiousness.
Rather than directly testing the elderly, the team looked at both male and female offspring who had an average age of 75.
"They're at the stage of their lives when they're cooking along at 110 percent," Perls said. "There's a number of things we can study in them that we can't" in centenarians.
Both males and females scored in the low range for being neurotic and the high range for being extroverted.
Women scored high in agreeableness, while men scored normal. Both sexes tested normal for conscientiousness and openness, according to the study, published in the April issue of the Journal of the American Geriatrics Society.
Buettner has not studied the children of centenarians, though that methodology is "absolutely" valid, he said.
(Buettner has also received funding from the National Geographic Society, which owns National Geographic News.)
In the blue zone of Okinawa, Japan, Buettner asked expert Nobuyoshi Hirose what he thought explains Okinawans' longevity.
"He thought for a moment, and said, They're likable people," Buettner said.
That likeability translates to a robust social circle, one of the common threads among the long-lived, Buettner added.
Improvements
Though many aspects of our personalities are already set by our genes, Buettner said, we can all make lifestyle improvements to help us live longer.
For one, becoming more extroverted—and by extension widening our social networks—can be cultivated and trained, Buettner said.
Also high on his list is eating a plant-based diet—"the more meat you eat, the quicker you die," he said.
And having a clear sense of purpose in your life, he added, is worth seven years of life expectancy.
Study leader Perls added that numerous strategies exist to deal with stress, such as exercising, meditation, or just taking a "nice deep breath."
"It's a matter of setting aside the time and effort to effectively manage your stress well," he said. "One of the keys is to realize how important it is to do that."
While this study does support the theory we were meant to eat a plant based diet, the advice to stop worrying seemed opposite of what I would think to expect. Caution usually equals you spread your genes, but I think this is suggeting that the worrying gets in the way of broadening social networds.
What is it about a large social network that evolution psychology would say extends someone's life? My guesses are resources, support during rough times, a feeling of belonging, or protection from enemies.
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