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The Most Popular Online Course Teaches You to Learn

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And the course is free if you don’t care about the certificate. (If you do want a certificate, it’s $49.) John Markoff describes the course in this NY Times column from last December:

The world’s most popular online course is a general introduction to the art of learning, taught jointly by an educator and a neuroscientist.

“Learning How To Learn,” which was created by Barbara Oakley, an electrical engineer, and Terry Sejnowski, a neuroscientist, has been ranked as the leading class by enrollment in a survey of the 50 largest online courses released earlier this month by the Online Course Report website.

The course is “aimed at a broad audience of learners who wanted to improve their learning performance based on what we know about how brains learn,” said Dr. Sejnowski, the director of the Computational Neurobiology Laboratory at the Salk Institute for Biological Studies in La Jolla, Calif.

With 1,192,697 students enrolled since the course was created last year, “Learning How to Learn,” which is offered by the University of California through Coursera, an online learning company which has partnered with a number of universities, has narrowly edged out the more tightly focused course, “Machine Learning,” taught by Stanford University professor Andrew Ng, which currently has 1,122,031 students enrolled.

The similar enrollment figures are striking in part because the field of machine learning has become one of the hottest university areas of study in recent years. High technology companies are competing intensely in Silicon Valley and elsewhere for newly minted data scientists.

The enrollment figures indicate that massively open online courses, or MOOCs, which in 2012 emerged as a potentially disruptive force that some believed might threaten the modern educational system, are continuing to evolve and gaining broad acceptance as part of an increasingly diverse marketplace for online education.

The Achilles heel of the MOOC phenomena has been that while enrollments have been huge, the number of students who actually complete courses for credit has remained low. That has led traditional educators to argue that the new technology would fail because students are generally less motivated to complete coursework online.

The completion rate — or “stickiness” — of the “Learning How to Learn” course has been above 20 percent, said Dr. Sejnowski, roughly twice the average for most MOOCs. He said the course is now attracting about 2,000 new students a day from 200 countries. The course was created after the two researchers met at the National Science Foundation-financed Science of Learning Center at the University of California at San Diego, which Dr. Sejnowski directs.

Dr. Oakley, a professor of engineering at Oakland University in Michigan, acknowledged that although only roughly 50,000 of the more than one million enrollees in her course had actually received a certificate for the course, certification was the wrong metric to understand the impact of the new form of online education. . .

Continue reading.

Written by LeisureGuy

25 September 2016 at 8:35 am

A headline that made me laugh: “Monsanto Agrees to Use Gene-Editing Tool CRISPR Responsibly”

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Here’s the article.

From the article:

. . . CRISPR/Cas9 has been taking the world by storm since it was first developed in 2013by researchers at the Broad Institute. The gene-editing technology works by taking advantage of a property of DNA called clustered regularly interspaced short palindromic repeats, or small repetitions of DNA base sequences. These sequences produce an enzyme called Cas9, which essentially functions as a pair of genetic scissors which can cut the DNA sequences at certain points to add or remove small DNA segments.

Yet the ease with which researchers and companies like Monsanto could use gene-editing technology to irreversibly fuck with living things like people and plants has also raised concern that the technology might become widely deployed without understanding the consequences. This is why the “responsible use” of CRISPR/Cas9 cited by Rozen is a key stipulation in Monsanto’s latest move to corner the GMO industry (as the most recent acquisition of the chemical company Bayer, Monsanto and its affiliates now control a full 25 percent of the world’s seeds and pesticides).

Monsanto has never been a company that has been particularly lauded for doingresponsible things, and its forays into genetically modified plants have had a number of unintended consequences, such as encouraging pesticide resistant “super bugs” and weeds. In order to ensure more responsible use of this powerful gene-editing tool, the agreement prohibits Monsanto from using CRISPR/Cas9 to promote gene drives (where a genetically modified trait, such as pesticide resistance, is intentionally spread through an entire plant population), the production of sterile “terminator” seeds, or the production of tobacco to be used for smoking.

Gene drives were recently cited as a concern in a National Academy of Sciences reporton the topic since genetically modified plant traits could ravage ecosystems in ways that aren’t yet fully understood. . .

This will not end well.

Written by LeisureGuy

24 September 2016 at 1:54 pm

The long fight, humans v. rats, may be drawing to a close

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Very interesting article by Jordan Kisner in the Guardian:

First, the myths. There are no “super rats”. Apart from a specific subtropical breed, they do not get much bigger than 20 inches long, including the tail. They are not blind, nor are they afraid of cats. They do not carry rabies. They do not, as was reported in 1969 regarding an island in Indonesia, fall from the sky. Their communities are not led by elusive, giant “king rats”. Rat skeletons cannot liquefy and reconstitute at will. (For some otherwise rational people, this is a genuine concern.) They are not indestructible, and there are not as many of them as we think. The one-rat-per-human in New York City estimate is pure fiction. Consider this the good news.

In most other respects, “the rat problem”, as it has come to be known, is a perfect nightmare. Wherever humans go, rats follow, forming shadow cities under our metropolises and hollows beneath our farmlands. They thrive in our squalor, making homes of our sewers, abandoned alleys, and neglected parks. They poison food, bite babies, undermine buildings, spread disease, decimate crop yields, andvery occasionally eat people alive. A male and female left to their own devices for one year – the average lifespan of a city rat – can beget 15,000 descendants.

There may be no “king rat”, but there are “rat kings”, groups of up to 30 rats whose tails have knotted together to form one giant, swirling mass. Rats may be unable to liquefy their bones to slide under doors, but they don’t need to: their skeletons are so flexible that they can squeeze their way through any hole or crack wider than half an inch. They are cannibals, and they sometimes laugh (sort of) – especially when tickled. They can appear en masse, as if from nowhere, moving as fast as seven feet per second. They do not carry rabies, but a 2014 study from Columbia University found that the average New York City subway rat carried 18 viruses previously unknown to science, along with dozens of familiar, dangerous pathogens, such as C difficile and hepatitis C. As recently as 1994 there was a major recurrence of bubonic plague in India, an unpleasant flashback to the 14th century, when that rat-borne illness killed 25 million people in five years. Collectively, rats are responsible for more human death than any other mammal on earth.

Humans have a peculiar talent for exterminating other species. In the case of rats, we have been pursuing their total demise for centuries. We have invented elaborate, gruesome traps. We have trained dogs, ferrets, and cats to kill them. We have invented ultrasonic machines to drive them away with high-pitched noise. (Those machines, still popular, do not work.) We have poisoned them in their millions. In 1930, faced with a rat infestation on Rikers Island, New York City officials flushed the area with mustard gas. In the late 1940s, scientists developed anticoagulants to treat thrombosis in humans, and some years later supertoxic versions of the drugs were developed in order to kill rats by making them bleed to death from the inside after a single dose. Cityscapes and farmlands were drenched with thousands of tons of these chemicals. During the 1970s, we used DDT. These days, rat poison is not just sown in the earth by the truckload, it is rained from helicopters that track the rats with radar – in 2011 80 metric tonnes of poison-laced bait were dumped on to Henderson Island, home to one of the last untouched coral reefs in the South Pacific. In 2010, Chicago officials went “natural”: figuring a natural predator might track and kill rats, they released 60 coyotes wearing radio collars on to the city streets.

Still, here they are. According to Bobby Corrigan, the world’s leading expert on rodent control, many of the world’s great cities remain totally overcome. “In New York – we’re losing that war in a big way,” he told me. Combat metaphors have become a central feature of rat conversation among pest control professionals. In Robert Sullivan’s 2014 book Rats, he described humanity’s relationship with the species as an “unending and brutish war”, a battle we seem always, always to lose.

Why? How is it that we can send robots to Mars, build the internet, keep alive infants born so early that their skin isn’t even fully made – and yet remain unable to keep rats from threatening our food supplies, biting our babies, and appearing in our toilet bowls?

rankly, rodents are the most successful species,” Loretta Mayer told me recently. “After the next holocaust, rats and Twinkies will be the only things left.” Mayer is a biologist, and she contends that the rat problem is actually a human problem, a result of our foolish choices and failures of imagination. In 2007, she co-founded SenesTech, a biotech startup that offers the promise of an armistice in a conflict that has lasted thousands of years. The concept is simple: rat birth control

The rat’s primary survival skill, as a species, is its unnerving rate of reproduction. Female rats ovulate every four days, copulate dozens of times a day and remain fertile until they die. (Like humans, they have sex for pleasure as well as for procreation.) This is how you go from two to 15,000 in a single year. When poison or traps thin out a population, they mate faster until their numbers regenerate. Conversely, if you can keep them from mating, colonies collapse in weeks and do not rebound.

Solving the rat problem by putting them on the pill sounds ridiculous. Until recently no pharmaceutical product existed that could make rats infertile, and even if it had, there was still the question of how it could be administered. But if such a thing were to work, the impact could be historic. Rats would die off without the need for poison, radar or coyotes.

SenesTech, which is based in Flagstaff, Arizona, claims to have created a liquid that will do exactly that. In tests conducted in Indonesian rice fields, South Carolina pig farms, the suburbs of Boston and the New York City subway, the product, called ContraPest, caused a drop in rat populations of roughly 40% in 12 weeks. This autumn, for the first time, the company is making ContraPest available to commercial markets in the US and Europe. The team at SenesTech believes it could be the first meaningful advance in the fight against rats in a hundred years, and the first viable alternative to poison. Mayer was blunt about the implications: “This will change the world.”

Mayer is a tall, vigorous woman in her mid-60s with bright eyes, spiky grey hair and a toothy grin. Her ideologies of choice are Buddhism and the Girl Scouts. “It’s kind of my core,” she said of the latter, “to do for others.” In conversation, her manner is so upbeat that she seems to be holding forth radiantly before an audience or on the verge of bursting into song. When asked how she is doing, she frequently responds in a near-rapture: “If I was any better, I’d be a twin!” – she also appears to enjoy watching people wonder whether this is an expression they should know.

When I took a seat in her office earlier this year, she clapped her hands triumphantly and said “Ooh! You’re sitting in history and strength!” There was a pause. “I had a feng shui person come and do my office,” she explained. . .

Continue reading.

There’s a lot more, and it’s interesting, informative, and intertaining (the three I’s). Later in the article:

It sounds crazy: a band of animal lovers and firemen in the mountains of Arizona, led by a Buddhist girl scout, making a pink milkshake for rats that may eventually improve the lives of millions of people. They are unruffled by scepticism: In the middle of one interview, Mayer forgot a detail and yelled towards the door, “Cheryl, who said to you, ‘That’s just not how we do it?’” Dyer hollered back from the other room. “Which time?” In response, they point to hard science, solicitations from governments and companies around the world, and an endorsement from Stephen Hawking, who featured them on his documentary mini-series Brave New World.

Written by LeisureGuy

24 September 2016 at 11:08 am

FBI and DOJ Vow to Continue Using Junk Science Rejected by White House Report

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Apparently the FBI and DOJ operate independently of the White House, which may in fact be true: it’s not a good idea for the President to be deciding what the DoJ and FBI should do, since they should follow the law. (It’s probably also not a good idea for the President to decide on his own authority to have American citizens killed with no due process and certainly no trial.)

Jordan Smith reports in The Intercept:

Although a report released this week by the President’s Council of Advisors on Science and Technology concludes that there is scant scientific underpinning to a number of forensic practices that have been used, for years, to convict thousands of individuals in criminal cases, the U.S. Department of Justice has indicated that it will ignore the report’s recommendations while the FBI has blasted the report as “erroneous” and “overbroad.”

The report, titled “Forensic Science in Criminal Courts: Ensuring Scientific Validity of Feature-Comparison Methods,” concludes that a number of common, pattern-matching forensic disciplines – bite mark analysis, fingerprint and firearm comparison, shoe tread analysis, and complex DNA mixture analysis – need additional support to be deemed scientifically valid and reliable – a conclusion in line with that reached in the groundbreaking 2009 report on forensics issued by the National Academy of Sciences National Research Council.

In a statement reported by the Wall Street Journal, Attorney General Loretta Lynch said that the agency remains “confident that, when used properly, forensic science evidence helps juries identify the guilty and clear the innocent, and the department believes that the current legal standards regarding the admissibility of forensic evidence are based on sound science and sound legal reasoning.” As such, she said, while “we appreciate their contribution to the field of scientific inquiry, the department will not be adopting the recommendations related to the admissibility of forensic science evidence.”

The DOJ did not respond to The Intercept’s request for additional information, but based on her statement, it appears Lynch is saying there’s simply nothing to see here and that the criminal justice system is working just fine.

The Intercept first reported on the report’s conclusions earlier this month, after obtaining a draft copy. The text of the final report, released Sept. 20, appears to be nearly identical to the leaked draft.

Foundational validity and reliability are essential to shore up forensic practices, the report concludes – attributes that are largely absent in the disciplines it reviewed, which rely heavily on the subjective determinations of practitioners. Pattern-matching forensics involve an examiner determining whether a piece of crime scene evidence can be visually matched to a suspect – whether an alleged bite mark on a victim’s hand matches a suspect’s dentition, for example, or whether a partial, or smudged, fingerprint found at the scene of a crime matches a clean print obtained from a suspect – determinations currently based primarily on a subjective eyeballing of the objects at issue.

“Foundational validity requires that a method has been subjected to empiricaltesting by multiple groups under conditions appropriate to its intended use,” reads the report. Such studies must demonstrate that a practice is “repeatable and reproducible” and must provide “valid estimates of the method’s accuracy” – in other words, a meaningful error rate. “The frequency with which a particular pattern or set of features will be observed in different samples, which is an essential element in drawing conclusions, is not a matter of ‘judgment.’ It is an empirical matter for which only empirical evidence is relevant,” the report continues. “For forensic feature-comparison methods, establishing foundational validity based on empirical evidence is thus a sine qua non. Nothing can substitute for it.”

For years forensic practitioners in many of the disciplines included in the White House report (as well as in the National Academy of Sciences report) have overstated in court the validity and reliability of their results. Consider the case of Bill Richards, for example, who spent nearly 23 years in prison for murdering his wife Pamela before the California Supreme Court last May overturned his conviction, concluding that Richards had been a victim of junk science and false testimony. In his case, a renowned forensic dentist testified that a mark found on Pamela’s hand was a clear match to Richards’s supposedly unique dentition. Notable, the dentist testified, was that Richards had an under-erupted canine tooth that would account for a void in the alleged bite-mark injury to Pamela’s hand; only “one or two or less” people out of 100 would have such a feature, he testified. The dentist, Dr. Norman “Skip” Sperber, ultimately recanted that testimony, saying that it had no scientific basis. The new White House report notes that it is unlikely that bite-mark evidence will ever be scientifically supported.

In all, the report makes eight overarching recommendations for improvement— to the National Institute of Standards and Technology, to the FBI, to the attorney general, and to the judiciary — and called for “a vigorous research program” to improve forensic sciences building off “recent important” research conducted into fingerprint analysis, that the judiciary take into account actual scientific criteria when assessing whether forensic evidence and testimony should be allowed into court, and that the attorney general should “direct attorneys appearing [in court] on behalf of the [DOJ] to ensure expert testimony in court about forensic feature-comparison methods meets the scientific standards for scientific validity.”

“Where there are not adequate empirical studies and/or statistical models to provide meaningful information about the accuracy of a forensic feature-comparison method,” the report concludes, “DOJ attorneys and examiners should not offer testimony based on the method.” And in the event that testimony is necessary, the report says, the expert should “clearly acknowledge to courts” the lack of scientific evidence to support the underlying forensic practice.

Under “current legal standards,” and under the U.S. Supreme Court ruling in the 1993 case Daubert v. Merrell Dow Pharmaceuticals, federal judges are tasked with acting as gatekeepers over what expert testimony will be allowed into evidence. Where scientific – or supposedly scientific – evidence is concerned, the Supreme Court concluded that before allowing expert testimony in a case the trial judge must ensure that “any and all scientific testimony or evidence admitted is not only relevant, but reliable” which necessitates, in part, an assessment of “whether the reasoning or methodology underlying the [expert’s] testimony is scientifically valid.”

This, the new report correctly notes, is where science and the law intersect. But in practice, legal scholars note, the Daubert standard has not kept pseudoscience out of the courtroom. And when courts rely on precedent to allow certain questionable forensic practices into evidence the result is something like a feedback loop. “Bite-mark analysis has passed every Daubertchallenge that it has ever faced and [yet] there isn’t a scientist on the planet that would argue that bite-mark analysis is a valid and reliable science, aside from the few practitioners who still cling to that belief,” said Chris Fabricant, director of strategic litigation for the Innocence Project and a vocal critic of the use of junk science.

Fabricant said the DOJ’s rejection out-of-hand of the White House report is disheartening. “You would think that they would want to get it right. The idea is not that we’re going to spring open the jailhouse doors and let everybody free. The idea is that scientific evidence ought to be scientific,” he said. “To simply reject the call for more research and to say that Daubert is sufficient is ludicrous, because Daubert is obviously not sufficient,” he continued. “So, the idea that you would point to the courts and to precedent for the idea that forensic evidence is good enough for government work is a joke.”

Attorney General Lynch was not alone in her rejection of the science council’s report. The FBI also . . .

Continue reading.

It’s important and it shows clearly how out of whack a good part of the government is.

Written by LeisureGuy

23 September 2016 at 8:56 pm

The play gap

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A very interesting article by Todd Oppenheimer in Craftsmanship magazine:

Several years ago, Janice O’Donnell, the director of the Providence Children’s Museum, conducted a survey of public school superintendents in her community to see how much recess time was available to students. Virtually everyone who responded said they considered recess important, but only a tiny percentage of the schools actually offered it anymore. When O’Donnell started looking into why this was happening, not only in Rhode Island but elsewhere in the country, she was stunned by what she learned.

Over the last 10 to 15 years, many teachers felt their students no longer had time for recess. With the increased emphasis put on standardized testing, their primary job now was to make sure students got high scores. Playtime could be handled after school. At other schools, especially those in crowded inner city neighborhoods, there was no longer any space for playgrounds, or even a basketball hoop. Among those who could and did offer recess, many teachers used it for leverage with difficult students. If they misbehaved, or didn’t finish their work, they had to stay in class during recess. And the pattern in poor urban communities was the worst.

In many inner city neighborhoods, after-school playtime has become a fiction. “Half these kids end up in after-school programs for homework help,” O’Donnell told me. The supervisors assigned to these programs, she added, are typically unskilled; students therefore tend to make little progress, which means they continually get assigned to more of it. Those who aren’t in after-school study often go to schools with few other after-school programs, such as organized sports. In the most troubled communities, once these youngsters get home, the options are even bleeker. The adults in the family are either working, or absent entirely. “They can’t roam their neighborhoods,” O’Donnell says, “so they’re on their screens.”

In the meantime, other opportunities for growth in school were shrinking as well. To allow more time for serious study, subjects such as music and art were being dropped. In some cases, even science classes were getting cut, because the new federal education law only monitored math and reading.

Schools with formal Physical Education programs don’t necessarily fill these gaps, either. In 2007, in a survey of 1,005 schools, the Robert Wood Johnson Foundation found that physical activity during PE isn’t a robust as we think. When opportunities for activity were compared between PE, recess, and after-school programs, recess won. It commanded 42 percent of a youngster’s chances to be active, as compared with PE, which came in at 32 percent. (After-school activities were lower still, at 26 percent.)

As time went on, O’Donnell noticed the growing mound of literature supporting the importance of recess, along with other opportunities for free play. The studies showed that active, open-ended play not only makes for happier, calmer kids, it also is critical to our full development—intellectually, physically, and emotionally.

The irony in that finding was certainly not lost on O’Donnell, or on the large number of experts in child development who study American education. Here we have a system intent on improving student’s abilities in subjects like math and reading by spending more time on those subjects in younger years; in the process, we sideline the very exercises that might build up our capacities to use math and reading in the richest way.

Adding to that irony is yet another one: . . .

Continue reading.

Written by LeisureGuy

23 September 2016 at 2:04 pm

More on the contemptible response of the FBI, Department of Justice, and prosecutors to unwelcome facts

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Those who dedicate their lives and careers to winning convictions are not interested in anything, valid or not, that makes winning a conviction the least bit more difficult. It seems that the majority of the FBI, prosecutors, and DoJ do not really care whether the evidence they use is accurate or not: their sole focus is on winning convictions, and to hell with evidence.

Our criminal justice system has just put on public display the degree of its corruption, and it’s an ugly sight. Daniel Denvir writes in Salon:

Under fire yet again, law enforcement is fighting back. Facing heavy criticism for misconduct and abuse, prosecutors are protesting a new report from President Obama’s top scientific advisors that documents what has long been clear: much of the forensic evidence used to win convictions, including complex DNA samples and bite mark analysis, is not backed up by credible scientific research.

Although the evidence of this is clear, many in law enforcement seem terrified that keeping pseudoscience out of prosecutions will make them unwinnable. Attorney General Loretta Lynch declined to accept the report’s recommendations on the admissibility of evidence and the FBI accused the advisors of making “broad, unsupported assertions.” But the National District Attorneys Association, which represents roughly 2,5000 top prosecutors nationwide, went the furthest, taking it upon itself to, in its own words, “slam” the report.

Prosecutors’ actual problem with the report, produced by some of the nation’s leading scientists on the President’s Council of Advisors on Science and Technology, seems to be unrelated to science. Reached by phone NDAA president-elect Michael O. Freeman could not point to any specific problem with the research and accused the scientists of having an agenda against law enforcement.

“I’m a prosecutor and not a scientist,” Freeman, the County Attorney in Hennepin County, Minnesota, which encompasses Minneapolis, told Salon. “We think that there’s particular bias that exists in the folks who worked on this, and they were being highly critical of the forensic disciplines that we use in investigating and prosecuting cases.”

That response, devoid of any reference to hard science, has prompted some mockery, including from Robert Smith, Senior Research Fellow and Director of the Fair Punishment Project at Harvard Law School, who accused the NDAA of “fighting to turn America’s prosecutors into the Anti-Vaxxers, the Phrenologists, the Earth-Is-Flat Evangelists of the criminal justice world.”

It has also, however, also lent credence to a longstanding criticism that American prosecutors are more concerned with winning than in establishing a defendant’s guilt beyond a reasonable doubt.

“Prosecutors should not be concerned principally with convictions; they should be concerned with justice,” said Daniel S. Medwed, author of “Prosecution Complex: America’s Race to Convict and Its Impact on the Innocent” and a professor at Northern University School of Law, told Salon. “Using dodgy science to obtain convictions does not advance justice.”

In its press release, the NDAA charged that the scientists, led by Human Genome Project leader Eric Lander, lack necessary “qualifications” and relied “on unreliable and discredited research.” Freeman, asked whether it the NDAA was attempting to discredit scientific research without having scientists evaluate that research, demurred.

“I appreciate your question and I can’t respond to that,” he said.

Similarly, Freedman was unable to specify any particular reason that a member of the council might be biased against prosecutors.

“We think that this group of so-called experts had an agenda,” he said, “which was to discredit a lot of the science…used by prosecutors.”

The report, “Science in Criminal Courts: Ensuring Scientific Validity of Feature-Comparison Methods,” was the result of a comprehensive review or more than 2,000 papers and produced in consultation with a bevvy of boldfaced names from the legal community. It found that there is no solid scientific basis to support the analyses of bite marks, firearms, biological samples containing the DNA of multiple individuals and footwear. The report also found that the certainty of latent fingerprint analysis is often overstated, and it criticized proposed Justice Department guidelines defending the validity of hair analysis as being grounded in “studies that do not establish [its] foundational validity and reliability.”

The new report is comprehensive but hardly the first time that scientific research has cast doubt on the reliability of evidence used in trials — everything from eyewitness identification to arson investigations. The report cites a 2002 FBI reexamination of their own scientists’ microscopic hair comparisons and found that DNA testing showed 11 percent of the samples that had been found to match in reality came from different people. A 2004 National Research Council report cited found there was an insufficient basis upon which to draw “a definitive connection between two bullets based on compositional similarity of the lead they contain.”

One of the most important developments in recent decades has been DNA science, which has not only proven that defendants have been wrongfully convicted but also raised questions about the forensic evidence used to win those convictions.

In the Washington Post, University of Virginia law professor Brandon L. Garrettdescribes the case of Keith Harward, who was exonerated on April 8 for a Newport News, Virginia rape and murder that DNA evidence later showed someone else committed. His conviction, for which he spent 33 years behind bars, hinged on the false testimony of two purported experts who stated that his teeth matched bite marks on the victim’s body.

“Of the first 330 people exonerated by DNA testing, 71 percent, or 235 cases, involved forensic analysis or testimony,” Garrett writes. “DNA set these people free, but at the time of their convictions, the bulk of the forensics was flawed.”

In an interview, Garrett called the NDAA response “juvenile.”

“The response seems to be you say that certain forensic sciences are unscientific, well you’re unscientific,” said Garrett. “To call a group of the leading scientists in the world unscientific, it’s just embarrassing….I really doubt that they speak for most prosecutors.”

Many cases, the report found, have “relied in part on faulty expert testimony from forensic scientists who had told juries incorrectly that similar features in a pair of samples taken from a suspect and from a crime scene (hair, bullets, bitemarks, tire or shoe treads, or other items) implicated defendants in a crime with a high degree of certainty.”

Expert witnesses have often overstated the certainty of their findings, declaring that they were 100-percent certain when in fact 100-percent certainty is scientifically impossible.

Forensic science has largely been developed within law enforcement and not by independent scientists, said Medwed. In the case of bite mark analysis, the report concludes that the method is basically worthless. But by and large, the report calls not for the science to be thrown out forever but to be improved so that it is in fact reliable.

“The NDAA response strikes me as a bit defensive to say the least and puzzling because my hope is that in looking at this report the reaction of prosecutors would be, how do we improve the system,” said Medwed. “Even if they believe that some of these disciplines are legitimate, how do we further test them, and refine them so they can be better?”

The NDAA, however, not only dismisses the scientific research in question but asserts that scientific expertise has no role to play in determining what kind of evidence judges decide to admit into court. . .

Continue reading.

Ignorance is bad, stupidity is worse, and combination is deadly. It’s a bad sign that so many in law enforcement and among prosecutors seem to embrace ignorance with enthusiasm.

Written by LeisureGuy

23 September 2016 at 1:57 pm

Observing evolution as it happens

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Emily Singer writes in Quanta:

When Rosemary and Peter Grant first set foot on Daphne Major, a tiny island in the Galápagos archipelago, in 1973, they had no idea it would become a second home. The husband and wife team, now emeritus biology professors at Princeton University, were looking for a pristine environment in which to study evolution. They hoped that the various species of finches on the island would provide the perfect means for uncovering the factors that drive the formation of new species.

The diminutive island wasn’t a particularly hospitable place for the Grants daphneisland-615x399to spend their winters. At less than one-hundredth the size of Manhattan, Daphne resembles the tip of a volcano rising from the sea. Visitors must leap off the boat onto the edge of a steep ring of land that surrounds a central crater. The island’s vegetation is sparse. Herbs, cactus bushes and low trees provide food for finches — small, medium and large ground finches, as well as cactus finches — and other birds. The Grants brought with them all the food and water they would need and cooked meals in a shallow cave sheltered by a tarp from the baking sun. They camped on Daphne’s one tiny flat spot, barely larger than a picnic table.

Though lacking in creature comforts, Daphne proved to be a fruitful choice. The Galápagos’ extreme climate — swinging between periods of severe drought and bountiful rain — furnished ample natural selection. Rainfall varied from a meter of rain in 1983 to none in 1985. A severe drought in 1977 killed off many of Daphne’s finches, setting the stage for the Grants’ first major discovery. During the dry spell, large seeds became more plentiful than small ones. Birds with bigger beaks were more successful at cracking the large seeds. As a result, large finches and their offspring triumphed during the drought, triggering a lasting increase in the birds’ average size. The Grants had observed evolution in action.

That striking finding launched a prolific career for the pair. They visited Daphne for several months each year from 1973 to 2012, sometimes bringing their daughters. Over the course of their four-decade tenure, the couple tagged roughly 20,000 birds spanning at least eight generations. (The longest-lived bird on the Grants’ watch survived a whopping 17 years.) They tracked almost every mating and its offspring, creating large, multigenerational pedigrees for different finch species. They took blood samples and recorded the finches’ songs, which allowed them to track genetics and other factors long after the birds themselves died. They have confirmed some of Darwin’s most basic predictions and have earned a variety of prestigious science awards, including the Kyoto Prize in 2009.

Now nearly 80, the couple have slowed their visits to the Galápagos. These days, they are most excited about applying genomic tools to the data they collected. They are collaborating with other scientists to find the genetic variants that drove the changes in beak size and shape that they tracked over the past 40 years.Quanta Magazine spoke with the Grants about their time on Daphne; an edited and condensed version of the conversation follows.

QUANTA MAGAZINE: Why did you decide to go to the Galápagos? What drew you to study finches specifically?

ROSEMARY GRANT: I had more of a genetics background and Peter more of an ecological background. But we were both interested in the same process — how and why species form. We both wanted to choose a population that was variable in a natural environment.

The Galápagos had several things that were very important. The islands are young, and there are lots of populations of finches that occur together and separately on the different islands. The islands were in close to pristine condition, having never been inhabited by humans. We knew that any changes would be natural changes and not the result of human interference.

The climate is extremely dynamic. The archipelago lies astride the equator and is subject to the El Niño–Southern Oscillation phenomenon. There are years with a terrific amount of rainfall, which is very good for finches. But it can also get years of drought, when many birds die. We now know that up to 80 to 90 percent of birds on the small islands die in times of drought. Those extremes would give us the opportunity to measure the climate variations that occurred and the evolutionary responses to those changes.

PETER GRANT: We had three main questions in mind. First, how are new species formed? That’s the Darwinian question of the origin of species. Second, do species compete for food? If they do, what effect does that have on the structure of animal communities? That was a hot topic in the early 1980s. There was very little experimental evidence at the time, so there was plenty of scope for taking a position one way or another. Third, why do some populations exhibit large variation in morphological traits like body size and beak size?

What was it like stepping on the island for the first time? . . .

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Written by LeisureGuy

22 September 2016 at 6:22 pm

Posted in Evolution, Science

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