/////////////NYT=....Your Old Man
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By LISA BELKIN
Published: April 1, 2009
Read between the lines of a recent study out of Australia and you can see hints of a coming shift in the gender conversation. Researchers at the University of Queensland found that children born to older fathers have, on average, lower scores on tests of intelligence than those born to younger dads. Data they analyzed from more than 33,000 American children showed that the older the man when a child is conceived, the lower a child’s score is likely to be on tests of concentration, memory, reasoning and reading skills, at least through age 7.
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Pablo Picasso, 66, with his son Claude.
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Lisa Belkin Discusses Mens' Biological Clocks on The Takeaway
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Letters: Your Old Man (April 19, 2009)
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It was a small difference — just a few I.Q. points separated a child born to a 20-year-old and a child born to a 50-year-old. But it adds weight to a new consensus-in-the-making: there is no fountain of youth for sperm, no “get out of aging free” card. The little swimmers, scientists are finding, one study at a time, get older and less dependable along with every other cell in the male body.
And men don’t have to be all that old to be “too old.” French researchers reported last year that the chance of a couple’s conceiving begins to fall when the man is older than 35 and falls sharply if he is older than 40. British and Swedish researchers, in turn, have calculated that the risk of schizophrenia begins to rise for those whose fathers were over 30 when their babies were born. And another Swedish study has found that the risk of bipolar disorder in children begins to increase when fathers are older than 29 and is highest if they are older than 55. British and American researchers found that babies born to men over the age of 40 have significantly greater risk of autism than do those born to men under 30. (The age of the mother, in most of these studies, showed little or no correlation.)
Lay this latest I.Q. news atop the pile, and you find yourself reaching the same conclusion as Dr. Dolores Malaspina, a professor of psychiatry at New York University Medical Center, who has done some of the schizophrenia research: “It turns out the optimal age for being a mother is the same as the optimal age for being a father.”
For decades men have been diligently discovering their feminine side, and couples have been announcing “we’re pregnant”; yet the hows and whens of having a baby are still juggled primarily by women. We are the ones who hold the time lines and calendars in our heads, who have to surrender space in our bodies and clear time in our lives. Too soon could derail a career. Too late could risk infertility. Becoming a mother means compromising with biology — “settling” for a mate or for single-parenthood or for an ill-timed career interruption — in order to beat that clock.
The clock determines not only the odds of having a baby but also the odds of having a healthy baby. It doesn’t help that after age 35, a first-time mom finds “elderly primigravida” scrawled on her chart in the OB’s office. With each year comes greater risks of Down syndrome and low birth weight and prematurity. The message to women: you are the direct cause of your baby’s health; the message to men: you, too, could be Tony Randall. Women: you’d better hurry up. Men: you have all the time in the world.
The push and pull between timetables and dreams, between our bodies and our babies, is at the core of many women’s worldview, which also means it is at the core of relationships between the sexes. This tension feeds the stereotype of woman as eager to settle down and men as reluctant, and it’s the crux of why we see women as “old” and men as “distinguished.”
If those underlying assumptions were to change, would all that follows from them change as well? A world in which each man heard his clock tick even a fraction as urgently as each woman could be a very different world indeed. All those silver-haired sex symbols, and balding sugar daddies, and average-Joe divorced guys who are on their second families because they can be while their exes are raising their first set of kids — what if all of them became, in women’s eyes, too darned old?
What if 30-year-old women started looking at 50-year-old men as damaged goods, what with their washed-up sperm, meaning those 50-year-olds might actually have to date (gasp!) women their own age? What if men, as the years passed, began to look with new eyes at Ms. Almost Right? Would men of all ages come to understand — firsthand, not just from the sidelines — the fear that the very passage of time will put your not-yet-conceived baby at risk?
It could happen. True, the results of these studies are incremental and preliminary — a few I.Q. points here, a few hundred schizophrenia cases there. Yet for better or worse, we humans have proved that we’ll upend our lives over a few bits of cautionary data. This seems particularly true when it comes to parenting, where our responses are often visceral, not intellectual. Suggest that something might keep a child safer, or ensure his happy future, or get her into college, and today’s parents will bite.
In that context, choosing a father for your child according to his “sell-by date” would be perversely consistent — seen by some women as long-overdue comeuppance (hear the chortling yet at girls’ night out?) and by others (old habits die hard) as yet another thing they have to worry about when getting pregnant.
It will not change everything; it might not even change most things. But it would be a satisfying start if men had to pause and see age as part of their biological equation, too.
//////////////////////Junk DNA in two paragraphs
"Most people do not realize that all our genes only comprise about 3% of the total human genome. The rest is basically one large black box," says Kevin Verstrepen, heading the research team. "Why do we have this DNA, what is it doing?"
Scientists once believed that most of the DNA outside of genes, the so-called non-coding DNA, was useless trash that either entered the genome and never left or was remnants from earlier life. One commonly known example of such 'junk DNA' are the so-called tandem repeats - short stretches of DNA that are repeated head-to-tail. "At first sight, it may seem unlikely that this stutter-DNA has any biological function," says Marcelo Vinces, one of the lead authors on the paper. "On the other hand, it seems hard to believe that nature would foster such a wasteful system."
Unstable repeats
The international team of scientists found that stretches of tandem repeats influence the activity of neighboring genes. The repeats determine how tightly the local DNA is wrapped around specific proteins called 'nucleosomes', and this packaging structure dictates to what extent genes can be activated. Interestingly, tandem repeats are very unstable - the number of repeats changes frequently when the DNA is copied.
These changes affect the local DNA packaging, which in turn alters gene activity. In this way, unstable junk DNA allows fast shifts in gene activity, which may allow organisms to tune the activity of genes to match changing environments -a vital principle for survival in the endless evolutionary race.
////////////////////////.......Highfalutin' readers will already know that dogs are basically just friendly wolves. Seriously. At least 12,000 years ago, a bunch of wolves turned into dogs.
No one really really knows how it happened, but some scientists believe that wolves hanging around human settlements to eat garbage became dogs by accident.
///////////////World Optimism: 60 Percent Of Us Have Only 6 Percent Of Wealth - But 85 Percent Think It Will Get Better
////////////////SCIENCE BROWSING
/////////////////FLOE-FIRST LIVING ORGANISM EVER
LUCA
//////////////////As always in the case of postmodernism, a perfectly reasonable and potentially interesting idea (the non-independence of facts and theories, which was not discovered by postmodernists) gets blown out of proportion to justify an insane conclusion (that science is the same as religion, or that reason and faith are on the same epistemological level), a conclusion that very likely the author himself does not believe. A famous quip by philosopher Bertrand Russell comes to mind: I wish that all philosophers who do not believe in the existence of walls would get into a car and drive straight into a wall (any would do) at a speed proportional to their skepticism concerning the existence of the wall itself. We would at least get rid of a lot of bad philosophers, or literary critics.
///////////////////NEAR BUSY ROADS INCR RISK OF RHMTD ARTHRITIS
/////////////////JUMPING BEFORE BEING PUSHED
//////////////////To Everything There is a Season"
////////////////////NYT=May 14, 2009
Chemist Shows How RNA Can Be the Starting Point for Life
By NICHOLAS WADE
An English chemist has found the hidden gateway to the RNA world, the chemical milieu from which the first forms of life are thought to have emerged on earth some 3.8 billion years ago.
He has solved a problem that for 20 years has thwarted researchers trying to understand the origin of life — how the building blocks of RNA, called nucleotides, could have spontaneously assembled themselves in the conditions of the primitive earth. The discovery, if correct, should set researchers on the right track to solving many other mysteries about the origin of life. It will also mean that for the first time a plausible explanation exists for how an information-carrying biological molecule could have emerged through natural processes from chemicals on the primitive earth.
The author, John D. Sutherland, a chemist at the University of Manchester, likened his work to a crossword puzzle in which doing the first clues makes the others easier. “Whether we’ve done one across is an open question,” he said. “Our worry is that it may not be right.”
Other researchers say they believe he has made a major advance in prebiotic chemistry, the study of the natural chemical reactions that preceded the first living cells. “It is precisely because this work opens up so many new directions for research that it will stand for years as one of the great advances in prebiotic chemistry,” Jack Szostak of the Massachusetts General Hospital wrote in a commentary in Nature, where the work is being published on Thursday.
Scientists have long suspected that the first forms of life carried their biological information not in DNA but in RNA, its close chemical cousin. Though DNA is better known because of its storage of genetic information, RNA performs many of the trickiest operations in living cells. RNA seems to have delegated the chore of data storage to the chemically more stable DNA eons ago. If the first forms of life were based on RNA, then the issue is to explain how the first RNA molecules were formed.
For more than 20 years researchers have been working on this problem. The building blocks of RNA, known as nucleotides, each consist of a chemical base, a sugar molecule called ribose and a phosphate group. Chemists quickly found plausible natural ways for each of these constituents to form from natural chemicals. But there was no natural way for them all to join together.
The spontaneous appearance of such nucleotides on the primitive earth “would have been a near miracle,” two leading researchers, Gerald Joyce and Leslie Orgel, wrote in 1999. Others were so despairing that they believed some other molecule must have preceded RNA and started looking for a pre-RNA world.
The miracle seems now to have been explained. In the article in Nature, Dr. Sutherland and his colleagues Matthew W. Powner and Béatrice Gerland report that they have taken the same starting chemicals used by others but have caused them to react in a different order and in different combinations than in previous experiments. they discovered their recipe, which is far from intuitive, after 10 years of working through every possible combination of starting chemicals.
Instead of making the starting chemicals form a sugar and a base, they mixed them in a different order, in which the chemicals naturally formed a compound that is half-sugar and half-base. When another half-sugar and half-base are added, the RNA nucleotide called ribocytidine phosphate emerges.
A second nucleotide is created if ultraviolet light is shined on the mixture. Dr. Sutherland said he had not yet found natural ways to generate the other two types of nucleotides found in RNA molecules, but synthesis of the first two was thought to be harder to achieve.
If all four nucleotides formed naturally, they would zip together easily to form an RNA molecule with a backbone of alternating sugar and phosphate groups. The bases attached to the sugar constitute a four-letter alphabet in which biological information can be represented.
“My assumption is that we are here on this planet as a fundamental consequence of organic chemistry,” Dr. Sutherland said. “So it must be chemistry that wants to work.”
The reactions he has described look convincing to most other chemists. “The chemistry is very robust — all the yields are good and the chemistry is simple,” said Dr. Joyce, an expert on the chemical origin of life at the Scripps Research Institute in La Jolla, Calif.
In Dr. Sutherland’s reconstruction, phosphate plays a critical role not only as an ingredient but also as a catalyst and in regulating acidity. Dr. Joyce said he was so impressed by the role of phosphate that “this makes me think of myself not as a carbon-based life form but as a phosphate-based life form.”
Dr. Sutherland’s proposal has not convinced everyone. Dr. Robert Shapiro, a chemist at New York University, said the recipe “definitely does not meet my criteria for a plausible pathway to the RNA world.” He said that cyano-acetylene, one of Dr. Sutherland’s assumed starting materials, is quickly destroyed by other chemicals and its appearance in pure form on the early earth “could be considered a fantasy.”
Dr. Sutherland replied that the chemical is consumed fastest in the reaction he proposes, and that since it has been detected on Titan there is no reason it should not have been present on the early earth.
If Dr. Sutherland’s proposal is correct it will set conditions that should help solve the many other problems in reconstructing the origin of life. Darwin, in a famous letter of 1871 to the botanist Joseph Hooker, surmised that life began “in some warm little pond, with all sorts of ammonia and phosphoric salts.” But the warm little pond has given way in recent years to the belief that life began in some exotic environment like the fissures of a volcano or in the deep sea vents that line the ocean floor.
Dr. Sutherland’s report supports Darwin. His proposed chemical reaction take place at moderate temperatures, though one goes best at 60 degrees Celsius. “It’s consistent with a warm pond evaporating as the sun comes out,” he said. His scenario would rule out deep sea vents as the place where life originated because it requires ultraviolet light.
A serious puzzle about the nature of life is that most of its molecules are right-handed or left-handed, whereas in nature mixtures of both forms exist. Dr. Joyce said he had hoped an explanation for the one-handedness of biological molecules would emerge from prebiotic chemistry, but Dr. Sutherland’s reactions do not supply any such explanation. One is certainly required because of what is known to chemists as “original syn,” referring to a chemical operation that can affect a molecule’s handedness.
Dr. Sutherland said he was working on this problem and on others, including how to enclose the primitive RNA molecules in some kind of membrane as the precursor to the first living cell.
/////////////////"The difference between an obstacle and an opportunity is our attitude towards it. Every opportunity has a difficulty, and every difficulty has an opportunity."-- J. Sidlo Baxter
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