DISCUSSION
GROUP
WHEN the Nobel prizewinning physicist Richard Feynman died in 1988, his blackboard carried the inscription, "What I cannot create, I do not understand." By that measure, biologists still have a lot to learn, because no one has yet succeeded in turning a chemical soup into a living, reproducing, evolving life form...... but - well read on
PICTURES OF A FEW ELEMENTS
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Washington Post
Washington Post Staff Writer
Thursday, December 2, 2010; 2:55 PM
All life on Earth - from microbes to elephants and us - is based on a single genetic model that requires the element phosphorus as one of its six essential components.
But now researchers have uncovered a bacterium that has five of those essential elements but has, in effect, replaced phosphorus with its look-alike but toxic cousin arsenic.
News of the discovery caused a scientific commotion, including calls to NASA from the White House and Congress asking whether a second line of earthly life has been found.
A NASA press conference Thursday and an accompanying article in the journal Science, gave the answer: No, the discovery does not prove the existence of a "second genesis" on Earth. But the discovery very much opens the door to that possibility and to the related existence of a theorized "shadow biosphere" on Earth - life evolved from a different common ancestor than all that we've known so far.
"Our findings are a reminder that life-as-we-know-it could be much more flexible than we generally assume or can imagine," said Felisa Wolfe-Simon, the young biochemist who led the effort after being selected as a NASA Astrobiology Research Fellow and as a member of the National Astrobiology Institute team at Arizona State University.
"If something here on Earth can do something so unexpected - that breaks the unity of biochemistry - what else can life do that we haven't seen yet?" she said.
The research, funded through NASA and conducted with samples from California's Mono Lake, found that some of the bacteria not only used arsenic to live, but had arsenic embedded into their DNA, RNA and other basic underpinnings.
"This is different from anything we've seen before," said Mary Voytek, senior scientist for NASA's program in astrobiology , the arm of the agency involved specifically in the search for life beyond Earth and for how life began here.
"These bugs haven't just replaced one useful element with another, they have the arsenic in the basic building blocks of their makeup," she said. "We don't know if the arsenic replaced phosphorus or if it was there from the very beginning - in which case it would strongly suggest the existence of a shadow biosphere."
Theoretical physicist and cosmologist Paul Davies, director of the Beyond Center at Arizona State and a prolific writer, is a co-author on the paper. He had been thinking about the idea for a decade and had written a paper in 2005. So had University of Colorado at Boulder philosopher and astrobiologist Carol Cleland. Both asked why nobody was looking for life with different origins on Earth, and Cleland coined the phrase "shadow biosphere."
At a Beyond Center conference four years ago, Wolfe-Simon, then in her late 20s, proposed a way to search for a possible shadow biosphere, and it involved Mono Lake and its arsenic.
"We were kicking vague ideas around, but she had a very specific proposal and then went out and executed it," Davies said. "It defies logic to think she found the only example of this kind of unusual life. Quite clearly, this is the tip of a huge iceberg."
All life as we know it contains six essential elements - carbon, oxygen, hydrogen, nitrogen, sulfur and phosphorus - that have qualities that make them seemingly ideal for their tasks. A form of phosphorus, for instance, is near perfect for building the framework for the DNA molecule, and another form is crucial to the transfer of energy within cells.
These forms of phosphorus are well suited for their job because they are especially stable in the presence of water. Arsenic is not, and that fact is one that raises concerns for some researchers familiar with the Mono Lake bugs.
Chemist Steven Benner of the Foundation for Applied Molecular Evolution in Florida has been involved in "shadow biosphere" research for several years, and will speak at the NASA unveiling of Wolfe-Simon's work. He says that the Mono Lake results are intriguing - "I do not see any simple explanation for the reported results that is broadly consistent with other information well known to chemistry" - but he says they are not yet proven. And a primary reason why is that arsenic compounds break down quickly in water while phosphorus compounds do not.
His conclusion: "It remains to be established that this bacterium uses arsenate as a replacement for phosphate in its DNA or in any other biomolecule."
Nonetheless, the paper and its results have created an excitement reminiscent of the 1995 announcement at NASA headquarters of the discovery of apparent signs of ancient life in a meteorite from Mars found in Antarctica. That finding was central to establishing the field of astrobiology, but was also broadly challenged and a scientific consensus evolved that the case for signs of life in the meteorite had not been proven.
The Mono Lake discovery highlights one of the central challenges of astrobiology - knowing what to look for in terms of extraterrestrial life. While it remains uncertain whether the lake's microbes represent another line of life, they show that organisms can have a chemical architecture different from what is currently understood to be possible.
"One of the guiding principles in the search for life on other planets, and of our astrobiology program, is that we should 'follow the elements,' " said Ariel Anbar, an ASU professor and biogeochemist. "Felisa's study teaches us that we ought to think harder about which elements to follow."
Mono Lake was selected as a work site by Wolfe-Simon because it is highly unusual and had been well studied by other scientists trying to answer different questions.
The lake receives run-off from the Sierra Nevada mountains, which have relatively high concentrations of arsenic. When the water arrives at Mono Lake, it has nowhere to go because there are no rivers carrying water further downstream. That means the arsenic, and other elements and compounds, can concentrate to unusally high levels. Arsenic is present in Mono Lake at a concentration 700 times greater than what the EPA considers safe.
Wolfe-Simon was invited to use the Menlo Park, Calif., lab of the U.S. Geological Survey and was aided in her work by senior research scientist Ron Oremland, who has studied arsenic in Mono Lake for decades. The initial work was quite simple: She took mud from the briny as well as toxic lake into the lab and began growing bacteria in Petri dishes. She gradually replaced phosphate salt with arsenic until the surviving bacteria could grow without needing the phosphates at all.
The bugs, an otherwise common bacteria in the halomonadaceae family, thrived without phosphates and with lots of arsenic. She then determined that the arsenic was embedded in the core genetic and energy transfer systems of the bacteria - that it appeared to have replaced (or preceeded) the phosphorus.
As she explained, replacing phosphorus with arsenic may seem suicidal, but the two are very similar in their makeup. Arsenic is considered toxic because most living things take it in and treat it like phosphorus, only to be destroyed by the small differences.
She said that while small amounts of the phosphorus remained in the arsenic-based bugs, she was able to determine that it was definitely not enough to supply the presumed phosphorus needs of the cell. That, she said, was being done with the arsenic.
"Sometimes I'm asked why something like this has never been found before, and the answer is that nobody has run the experiment before," Wolfe-Simon said. "There was nothing really complicated about it - I asked a simple question that was testable and got an answer."
Wolfe-Simon said she hopes to further test her findings in northern Argentina, where, she's been told, some microbes can not only tolerate arsenic, but absolutely need arsenic to survive.
Fri
13
Nov
2015
Are Languages Products of their Environment?
DISCOVER MAGAZINE published this very interesting article:
Languages Are Products of Their Environments
The characteristics that make each language unique may actually be adaptations to the acoustics of different
environments.
Tue
03
Jun
2014
The Case for Reparations
The Case for Reparations
Two hundred fifty years of slavery. Ninety years of Jim Crow. Sixty years of separate but equal. Thirty-five years of racist housing policy. Until we reckon with our compounding moral debts, America will never be whole.
By Ta-Nehisi Coates
May 21, 2014
Chapters
- I. “So That’s Just One Of My Losses”
- II. “A Difference of Kind, Not Degree”
- III. “We Inherit Our Ample Patrimony”
- IV. “The Ills That Slavery Frees Us From”
- V. The Quiet Plunder
- VI. Making The Second Ghetto
- VII. “A Lot Of People Fell By The Way”
- VIII. “Negro Poverty is not White Poverty”
- IX. Toward A New Country
- X. “There Will Be No ‘Reparations’ From Germany”
Mon
02
Jun
2014
A Look At 19th Century Children In The USA
PHILADELPHIA — DINNER with your children in 19th-century America often required some self-control. Berry stains in your daughter’s hair? Good for her. Raccoon bites running up your boy’s arms? Bet he had an interesting day.
As this year’s summer vacation begins, many parents contemplate how to rein in their kids. But there was a time when Americans pushed in the opposite direction, preserved in Mark Twain’s cat-swinging scamps. Parents back then encouraged kids to get some wildness out of their system, to express the republic’s revolutionary values.
The New York Times
Sunday Review
By JON GRINSPAN MAY 31, 2014
American children of the 19th century had a reputation. Returning British visitors reported on American kids who showed no respect, who swore and fought, who appeared — at age 10 — “calling for liquor at the bar, or puffing a cigar in the streets,” as one wrote. There were really no children in 19th-century America, travelers often claimed, only “small stuck-up caricatures of men and women.”
This was not a “carefree” nation, too rough-hewed to teach proper manners; adults deliberately chose to express new values by raising “go-ahead” boys and girls. The result mixed democracy and mob rule, assertiveness and cruelty, sudden freedom and strict boundaries. Visitors noted how American fathers would brag that their disobedient children were actually “young republicans,” liberated from old hierarchies. Children were still expected to be deferential to elders, but many were trained to embody their nation’s revolutionary virtues. “The theory of the equality” was present at the ballot box, according to one sympathetic Englishman, but “rampant in the nursery.”
Boys, in particular, spent their childhoods in a rowdy outdoor subculture. After age 5 or so they needed little attention from their mothers, but were not big enough to help their fathers work. So until age 10 or 12 they spent much of their time playing or fighting.
The writer William Dean Howells recalled his ordinary, violent Ohio childhood, immersed in his loose gang of pals, rarely catching a “glimpse of life much higher than the middle of a man.” Howells’s peers were “always stoning something,” whether friends, rivals or stray dogs. They left a trail of maimed animals behind them, often hurt in sloppy attempts to domesticate wild pets.
And though we envision innocents playing with a hoop and a stick, many preferred “mumbletypeg” — a game where two players competed to see who could throw a knife closer to his own foot. Stabbing yourself meant a win by default.
Left to their own devices, boys learned an assertive style that shaped their futures. The story of every 19th-century empire builder — Carnegie, Rockefeller, Vanderbilt — seems to begin with a striving 10-year-old. “Boy culture” offered training for the challenges of American manhood and a reprieve before a life of labor.
But these unsupervised boys also formed gangs that harassed the mentally ill, the handicapped and racial and ethnic minorities. Boys played an outsize role in the anti-Irish pogroms in 1840s Philadelphia, the brutal New York City draft riots targeting African-Americans during the Civil War and attacks on Chinese laborers in Gilded Age California. These children did not invent the bigotry rampant in white America, but their unrestrained upbringing let them enact what their parents mostly muttered.
Their sisters followed a different path. Girls were usually assigned more of their mothers’ tasks. An 8-year-old girl would be expected to help with the wash or other physically demanding tasks, while her brother might simply be too small, too slow or too annoying to drive the plow with his father. But despite their drudgery, 19th-century American girls still found time for tree climbing, bonfire building and waterfall-jumping antics. There were few pretty pink princesses in 19th-century America: Girls were too rowdy and too republican for that.
So how did we get from “democratic sucklings” to helicopter parents? Though many point to a rise of parental worrying after the 1970s, this was an incremental change in a movement that began a hundred years earlier.
In the last quarter of the 19th century, middle-class parents launched a self-conscious project to protect children. Urban professionals began to focus on children’s vulnerabilities. Well-to-do worriers no longer needed to raise tough dairymaids or cunning newsboys; the changing economy demanded careful managers of businesses or households, and restrained company men, capable of navigating big institutions.
Demographics played a role as well: By 1900 American women had half as many children as they did in 1800, and those children were twice as likely to live through infancy as they were in 1850. Ironically, as their children faced fewer dangers, parents worried more about their protection.
Instead of seeing boys and girls as capable, clever, knockabout scamps, many reconceived children as vulnerable, weak and naïve. Reformers introduced child labor laws, divided kids by age in school and monitored their play. Jane Addams particularly worked to fit children into the new industrial order, condemning “this stupid experiment of organizing work and failing to organize play.”
There was good reason to tame the boys and girls of the 19th century, if only for stray cats’ sake. But somewhere between Jane Addams and Nancy Grace, Americans lost track of their larger goal. Earlier parents raised their kids to express values their society trumpeted.
“Precocious” 19th-century troublemakers asserted their parents’ democratic beliefs and fit into an economy that had little use for 8-year-olds but idealized striving, self-made men. Reformers designed their Boy Scouts to meet the demands of the 20th century, teaching organization and rebalancing the relationship between play and work. Both movements agreed, in their didactic ways, that playtime shaped future citizens.
Does the overprotected child articulate values we are proud of in 2014? Nothing is easier than judging other peoples’ parenting, but there is a side of contemporary American culture — fearful, litigious, controlling — that we do not brag about but that we reveal in our child rearing, and that runs contrary to our self-image as an open, optimistic nation. Maybe this is why sheltering parents come in for so much easy criticism: A visit to the playground exposes traits we would rather not recognize.
There is, however, a saving grace that parents will notice this summer. Kids are harder to guide and shape, as William Dean Howells put it, “than grown people are apt to think.” It is as true today as it was two centuries ago: “Everywhere and always the world of boys is outside of the laws that govern grown-up communities.” Somehow, they’ll manage to go their own way.
________________________________
A National Endowment for the Humanities fellow at the Massachusetts Historical Society who is writing a book on the role of young people in 19th-century American democracy.
Mon
21
Apr
2014
Investigating Family's Wealth, China's Leader Signals a Change
From The New York Times
By CHRISTOPHER DREW and JAD MOUAWAD
APRIL 19, 2014
HONG KONG — His son landed contracts to sell equipment to state oil fields and thousands of filling stations across China. His son’s mother-in-law held stakes in pipelines and natural gas pumps from Sichuan Province in the west to the southern isle of Hainan. And his sister-in-law, working from one of Beijing’s most prestigious office buildings, invested in mines, property and energy projects.
In thousands of pages of corporate documents describing these ventures, the name that never appears is his own: Zhou Yongkang, the formidable Chinese Communist Party leader who served as China’s top security official and the de facto boss of its oil industry.
But President Xi Jinping has targeted Mr. Zhou in an extraordinary corruption inquiry, a first for a Chinese party leader of Mr. Zhou’s rank, and put his family’s extensive business interests in the cross hairs.
Even by the cutthroat standards of Chinese politics, it is a bold maneuver. The finances of the families of senior leaders are among the deepest and most politically delicate secrets in China. The party has for years followed a tacit rule that relatives of the elite could prosper from the country’s economic opening, which rewarded loyalty and helped avert rifts in the leadership.
Zhou Family Ties
Fri
13
Nov
2015
Are Languages Products of their Environment?
DISCOVER MAGAZINE published this very interesting article:
Languages Are Products of Their Environments
The characteristics that make each language unique may actually be adaptations to the acoustics of different
environments.
Tue
03
Jun
2014
The Case for Reparations
The Case for Reparations
Two hundred fifty years of slavery. Ninety years of Jim Crow. Sixty years of separate but equal. Thirty-five years of racist housing policy. Until we reckon with our compounding moral debts, America will never be whole.
By Ta-Nehisi Coates
May 21, 2014
Chapters
- I. “So That’s Just One Of My Losses”
- II. “A Difference of Kind, Not Degree”
- III. “We Inherit Our Ample Patrimony”
- IV. “The Ills That Slavery Frees Us From”
- V. The Quiet Plunder
- VI. Making The Second Ghetto
- VII. “A Lot Of People Fell By The Way”
- VIII. “Negro Poverty is not White Poverty”
- IX. Toward A New Country
- X. “There Will Be No ‘Reparations’ From Germany”
Mon
02
Jun
2014
A Look At 19th Century Children In The USA
PHILADELPHIA — DINNER with your children in 19th-century America often required some self-control. Berry stains in your daughter’s hair? Good for her. Raccoon bites running up your boy’s arms? Bet he had an interesting day.
As this year’s summer vacation begins, many parents contemplate how to rein in their kids. But there was a time when Americans pushed in the opposite direction, preserved in Mark Twain’s cat-swinging scamps. Parents back then encouraged kids to get some wildness out of their system, to express the republic’s revolutionary values.
The New York Times
Sunday Review
By JON GRINSPAN MAY 31, 2014
Mon
21
Apr
2014
Investigating Family's Wealth, China's Leader Signals a Change
From The New York Times
By CHRISTOPHER DREW and JAD MOUAWAD
APRIL 19, 2014
HONG KONG — His son landed contracts to sell equipment to state oil fields and thousands of filling stations across China. His son’s mother-in-law held stakes in pipelines and natural gas pumps from Sichuan Province in the west to the southern isle of Hainan. And his sister-in-law, working from one of Beijing’s most prestigious office buildings, invested in mines, property and energy projects.
In thousands of pages of corporate documents describing these ventures, the name that never appears is his own: Zhou Yongkang, the formidable Chinese Communist Party leader who served as China’s top security official and the de facto boss of its oil industry.
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