bringing in the sheaves

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Fist tap Dale.

modern cargo ships slow to the speed of clippers

Guardian | The world's largest cargo ships are travelling at lower speeds today than sailing clippers such as the Cutty Sark did more than 130 years ago.

A combination of the recession and growing awareness in the shipping industry about climate change emissions encouraged many ship owners to adopt "slow steaming" to save fuel two years ago. This lowered speeds from the standard 25 knots to 20 knots, but many major companies have now taken this a stage further by adopting "super-slow steaming" at speeds of 12 knots (about 14mph).

Travel times between the US and China, or between Australia and Europe, are now comparable to those of the great age of sail in the 19th century. American clippers reached 14 to 17 knots in the 1850s, with the fastest recording speeds of 22 knots or more.

Maersk, the world's largest shipping line, with more than 600 ships, has adapted its giant marine diesel engines to travel at super-slow speeds without suffering damage. This reduces fuel consumption and greenhouse gas emissions by 30%. It is believed that the company has saved more than £65m on fuel since it began its go-slow.

julian assange on the afghanistan war logs

Video - Julian Assange on the Wikileaks Afghanistan War Logs.

wikileaks afghanistan war logs

Guardian | It must be one of the biggest leaks in intelligence history. An archive of almost 90,000 files has come to light thanks to Wikileaks, logging the history of the war in Afghanistan, practically blow-by-blow. We've trawled through these incidents to help you make sense of the key events.

We have reproduced full military logs behind more than 200 of the key events from the database – you can navigate around them. But if you want to download this data to play with it yourself, this is the place to come.

These detailed reports show coalition forces' attacks on civilians, friendly fire incidents and Afghan forces attacking each other – so-called green on green.

wikileaks takes a new approach

WaPo | Wikileaks founder Julian Assange called the release of nearly 92,000 individual reports portraying a sputtering Afghan war effort "the nearest analogue to the Pentagon Papers." He was referring to the secret military documents that helped shift public opinion about the Vietnam War after they became public in 1971.

"It provides a whole map, if you like, through time, of what has happened during this war," said Assange, a native of Australia, in a television interview broadcast Sunday on Britain's public-service Channel 4.

He acknowledged that some will judge harshly the Web site's airing of classified documents, but he insisted that Wikileaks was not breaking the law or putting troops at risk. For the first time, Wikileaks decided unilaterally to delay the release of some documents because of the possibility that putting them out immediately could cause harm, he said.

"We believe that the way to justice is transparency, and we are clear that the end goal is to expose injustices in the world and try to rectify them," Assange said.

The publication of the documents also feeds an appetite for greater disclosure about the war, now in its ninth year.

"People want more details," said Steven Aftergood, director of the Federation for American Scientists' Project on Government Secrecy. "They want greater clarity and greater candor than they have gotten up to this point. Wikileaks, in this case, has filled a void left by the Pentagon."

The White House responded critically to the documents' release. "The United States strongly condemns the disclosure of classified information by individuals and organizations which could put the lives of Americans and our partners at risk, and threaten our national security," national security adviser James Jones said in a statement.
Jones called the leaks "irresponsible" and said the White House only learned from news organizations that the documents would be posted online. A senior administration official said officials are reviewing the documents to decide whether to take legal action against the site.

raw food raid - fight over what people put in their mouths

Video - LA Times reporter discussing raw food raid. (click story link to see guns drawn absurdity of one-time conducting the raid)

LATimes | With no warning one weekday morning, investigators entered an organic grocery with a search warrant and ordered the hemp-clad workers to put down their buckets of mashed coconut cream and to step away from the nuts.

Then, guns drawn, four officers fanned out across Rawesome Foods in Venice. Skirting past the arugula and peering under crates of zucchini, they found the raid's target inside a walk-in refrigerator: unmarked jugs of raw milk.

"I still can't believe they took our yogurt," said Rawesome volunteer Sea J. Jones, a few days after the raid. "There's a medical marijuana shop a couple miles away, and they're raiding us because we're selling raw dairy products?"

Cartons of raw goat and cow milk and blocks of unpasteurized goat cheese were among the groceries seized in the June 30 raid by federal, state and local authorities — the latest salvo in the heated food fight over what people can put in their mouths.

systemic fear, modern finance and the future of capitalism

B&N | Existing theories of political economy, liberal as well as Marxist, see capital as a dual entity. According to these theories, the "real" essence of capital consists of material/productive commodities, while the "financial" appearance of capital either accurately mirrors or fictitiously distorts this underlying reality. We reject this duality. Capital, we argue, is finance, and only finance. In its modern incarnation, capital exists as forward-looking capitalization, a universal financial ritual that discounts expected future earnings to a singular present value.

The universality of this reduction makes capitalization the most supple power instrument ever known to humanity. Previously, distributive power was associated with clear socio-ecological distinctions -- differences between king and subject, owner and slave, tiller and landlord, field and citadel, village and town. Capitalization flattens these qualitative features to the point of irrelevance. In principle, anyone can be a capitalist, and what distinguishes one capitalist from another is the quantity of their capitalization: the most powerful are those with the greatest capitalization (dominant capital), and those that hold that power achieve and augment it by increasing their capitalization faster than others (differential accumulation). In this way, capitalization crystallizes the power of capitalists to shape their world, as well as the resistance of those that oppose this power. It gauges the capitalists' success in directing production and consumption, in shaping ideology and culture, in affecting the law, public policy, conflict, war and even the environment. It is the all-encompassing algorithm that creorders -- or creates the order -- of the capitalist mode of power.

The purpose of our paper is to examine the breakdown of this algorithm. To be sure, this type of inquiry is hardly novel. Marxists have long searched for objective signs of capitalist collapse, preliminary omens that would foretell the system’s imminent disintegration. However, because of their dual conception of capital, they've tended to look for such signs in the so-called real sphere of production and consumption, while paying far less attention to finance, which, in their view, is merely a distorted mirror of that reality. But finance isn’t a mirror of real capital; it is real capital – and indeed the only real capital. So if we want to look for signs of systemic crisis and possible disintegration, our search should begin here, in the very ritual of capitalization.

The specific focus of the article is two historical ruptures of modern finance – the periods of 1929-1939 and 2000-2010. During both periods, capitalists abandoned the conventional forward-looking ritual of capitalization, resorting instead to the backward-looking posture of pre-modern finance. In our view, these rare episodes are of great importance for understanding the nature of capitalist confidence and the capitalists’ ability to rule – as well as the possibility that this system of rule will collapse. Our inquiry seeks, first, to characterize key features of these episodes; second, to speculate on their causes; and third, to assess, however speculatively, what they might imply for the future of capitalism.

the new science of morality

Video - BloggingHeads Paul Bloom breaks it down for Michael Murray.

Edge | Something radically new is in the air: new ways of understanding physical systems, new ways of thinking about thinking that call into question many of our basic assumptions. A realistic biology of the mind, advances in evolutionary biology, physics, information technology, genetics, neurobiology, psychology, engineering, the chemistry of materials: all are questions of critical importance with respect to what it means to be human. For the first time, we have the tools and the will to undertake the scientific study of human nature.

This began in the early seventies, when, as a graduate student at Harvard, evolutionary biologist Robert Trivers wrote five papers that set forth an agenda for a new field: the scientific study of human nature. In the past thirty-five years this work has spawned thousands of scientific experiments, new and important evidence, and exciting new ideas about who and what we are presented in books by scientists such as Richard Dawkins, Daniel C. Dennett, Steven Pinker, and Edward O. Wilson among many others.

In 1975, Wilson, a colleague of Trivers at Harvard, predicted that ethics would someday be taken out of the hands of philosophers and incorporated into the "new synthesis" of evolutionary and biological thinking. He was right.

Scientists engaged in the scientific study of human nature are gaining sway over the scientists and others in disciplines that rely on studying social actions and human cultures independent from their biological foundation.

No where is this more apparent than in the field of moral psychology. Using babies, psychopaths, chimpanzees, fMRI scanners, web surveys, agent-based modeling, and ultimatum games, moral psychology has become a major convergence zone for research in the behavioral sciences.

So what do we have to say? Are we moving toward consensus on some points? What are the most pressing questions for the next five years? And what do we have to offer a world in which so many global and national crises are caused or exacerbated by moral failures and moral conflicts? It seems like everyone is studying morality these days, reaching findings that complement each other more often than they clash.

status as a valued resource?

HPLabs | While the striving for status has long been recognized in animals and in humans, the role of status in their utility calculations has not been clarified. Specifically, the debate has not been settled whether people pursue status as a means to achieve power and resources or as an (emotional) goal in itself. We present results of a rent seeking experiment with human subjects from four different national cultures. Our results show that people regard status as a valued resource in itself, rather than a means to an end. Participants in the experiment played a two-stage game in which they tried to win a risky all-or-none rent. An analysis of the data established that the subjects valued status independently of any monetary consequence and were willing to trade-off some material gain in order to obtain it. This result was stable across the four cultures from Hong Kong, Turkey, the US, and Germany. Moreover, the amount of money that participants were willing to trade off against status corresponded to the Hofstede's power distance index of the respective culture. The power distance index of a culture has been shown to be correlated with the importance and acceptance of status symbols in that culture. Finally, the amount of status seeking observed was different among men and women, an intriguing observation that deserves further work.

kurzweil-vingesque?

Fist tap Dale.

now anything is possible....,

Video - rape by deception.

Guardian | Israel's liberal left has been warning about this for decades – and now those cautionary words seem like prophesies. Lines of Israeli authors, academics and campaigners have long said that the ugly occupation of the Palestinian people would corrode Israel and derail its democracy. Human rights advocates repeatedly warned that a nation capable of meting out such punishing discrimination to another people would eventually turn on itself. And so it has.

The country is in thrall to such anti-democratic sentiment and mob rule racism, manifesting at such breakneck speed that it is hard to keep up. In the last few months alone two Arab citizens of Israel were "disappeared" by the state's secret police; an Arab member of the Knesset was stripped of her parliamentary privileges for being on the Gaza aid flotilla; and now a Palestinian man from Jerusalem has just been convicted of rape after pretending to be Jewish and having consensual sex. This verdict, in effect turning the obfuscation of race into a criminal offence, also reveals the extent to which Israelis consider Palestinians to be abhorrent. Meanwhile, the Israeli children of migrant workers are threatened with expulsion, as a government campaign warns against hiring foreign workers.

Zero tolerance for the "other" in Israel has widened to include anyone questioning a twisted concept of loyalty to the state. The Association for Civil Rights in Israel (Acri) lists 14 antidemocratic laws currently working their way through parliament, from the demand that Arab citizens pledge allegiance to a "Jewish democracy" to attempts to gag Israeli rights groups. Acri representatives are denounced as "Arab-lovers" and "traitors" when they attend parliamentary hearings. All this has widespread support – in fact, one of the few causes to bring thousands of Israelis on to the streets was a recent ultra-orthodox protest for the right to segregate Ashkenazi children, of European origin, from their Middle Eastern Jewish classmates.

insect gut has mind of its own

Video - Visceral locomotory pistoning in crawling caterpillars.

The Scientist | In at least one species of caterpillar, the gut appears to slide freely back and forth, untethered to the surrounding tissue - an unusual mechanism that might help the insect digest food while it crawls up stems in search of its leafy meals.

"What they're describing here, as far as I know, has never been described in any other animal," said zoologist Michael LaBarbera, who studies invertebrate biomechanics at the University of Chicago and was not involved in the study, published this week in Current Biology.

For Manduca sexta caterpillars, crawling begins in the back of their approximately five centimeter long bodies. They lift up their rear legs, initiating a wave of contractions and elongations that eventually reaches the head. It seemed reasonable for first author of the paper, Michael Simon at Tufts University, to imagine that the internal organs would follow the same sort of motion.

But when he and his colleagues showered the caterpillars with high-energy X-rays from a particle accelerator - essentially getting their first look of their insides - they saw a frenetic and unexpected back and forth swooshing that did not look anything like what they could observe from the outside.

The swooshing revealed by the X-ray imaging came from air tubes, called trachea, that were attached to the intestine. "They looked like seaweed blowing in the ocean," Simon said. As soon as the caterpillars lifted their hind legs to begin crawling, the researchers could see the tracheas moving, as if the gut moved way before the rest of the body caught up.

the olm lives over 100 years!!!

Video - the long-lived olm.

The Scientist | A blind, cave-dwelling amphibian appears to live for more than 100 years, an inexplicable feat that may eventually (when explained) provide insights into aging in other species.

But first, scientists have to unravel the mystery of how the species -- known as "human fish" -- achieves such longevity. "We cannot, at this time, say how this animal manages to survive such a long time," said eco-physiologist Yann Voituron, from the Université Claude Bernard - Lyon, first author of the study published online today (July 21) in Biology Letters. He was able to calculate the animal's extreme longevity by studying over 50 years of birth and death records of a 400-animal captive breeding colony at the Station D'Ecologie Expérimental du CNRS in Moulis, France.

The human fish, also called an olm, is a small, pale salamander, weighing between 15 and 20 grams, that has evolved extreme longevity living blindly in the caves of Europe. It can also live for a year without eating and can survive in hypoxic conditions for years.

Voituron's calculations from the weekly records of the colony predicted the olm's maximum lifespan to be over 100 years, with an average lifespan of 68.5 years. The olm's longevity exceeds that of other amphibians of its size by several times, much the way humans live about four times longer than other animals their size.

Indeed, the runner-up for longest living amphibian, the giant Japanese salamander, weighs in around 25kg, 1000 times more massive than the olm. "It is rather strange to discover that [so small an] animal, weighing about 15-20 grams, is able to survive more than a century," said Voituron. "It's the first time we found this kind of profile for a vertebrate [other than humans]."

In one respect, the amphibian's longevity is not surprising, since it has a natural lack of predators, enabling it to evolve to favor long-term survival and less frequent reproduction.

In other respects, however, the human fish's ability to live 100 years makes no sense, biologically.

Several physiological traits are normally associated with long-lived animals: larger size, low metabolic rates, and high protection against oxidative stress. Examples include giant tortoises and elephants - animals that have large body masses and low basal metabolic rates.

The olm, however, doesn't show any of these traits. So why does it live so long?

exemplar

NYTimes | The White House and Agriculture Secretary Tom Vilsack apologized profusely and repeatedly on Wednesday to a black midlevel official for the way she had been humiliated and forced to resign her Agriculture Department job after a conservative blogger put out a misleading video clip that seemed to show her admitting antipathy toward a white farmer.

By the end of the day, the official, Shirley Sherrod, had gained instant fame and emerged as the heroine of a compelling story about race and redemption.

Pretty much everyone else had egg on his face — from the conservative bloggers and pundits who first pushed the inaccurate story to Mr. Vilsack, who looked stricken as he told reporters he had offered Ms. Sherrod, until Monday the Agriculture Department’s rural development director in Georgia, a new job that would give her a “unique opportunity” to help the agency move past its checkered civil rights history. She told him she would think about it.

“This is a good woman, she’s been put through hell and I could have and should have done a better job,” Mr. Vilsack said, as he conceded that he had ordered Ms. Sherrod’s firing in haste, without knowing that the video clip, from a speech she gave to the N.A.A.C.P., had been taken out of context. He said that he had acted on his own, and that there was “no pressure from the White House.”

Mr. Vilsack’s late-afternoon appearance capped a humiliating and fast-paced few days not only for the White House, but also for the N.A.A.C.P. and the national news media, especially the Fox News Channel and its hosts Bill O’Reilly and Sean Hannity, all of whom played a role in promoting the story about Ms. Sherrod.

The controversy illustrates the influence of right-wing Web sites like the one run by Andrew Breitbart, the blogger who initially posted the misleading and highly edited video, which he later said had been sent to him already edited. (Similarly, Mr. Breitbart used edited videos to go after Acorn, the community organizing group.) Politically charged stories often take root online before being shared with a much wider audience on Fox. The television coverage, in turn, puts pressure on other news media outlets to follow up.

The full video of Ms. Sherrod’s March speech to an N.A.A.C.P. gathering in Douglas, Ga., shows that it was a consciousness-raising story. Ms. Sherrod’s father was murdered in 1965 by white men who were never indicted; she spoke about how in response, she vowed to stay in the South and work for change. She married the Rev. Charles Sherrod, a civil rights leader and cofounder of the Student Nonviolent Coordinating Committee.

camouflage or character?

NYTimes | So, are the optimistic Darwinians wrong, and impartial morality beyond the reach of those monkeys we call humans? Does thoroughly logical evolutionary thinking force us to the conclusion that our love, loyalty, commitment, empathy, and concern for justice and fairness are always at bottom a mixture of selfish opportunism and us-ish clannishness? Indeed, is it only a sign of the effectiveness of the moral camouflage that we ourselves are so often taken in by it?

Speaking of what “thoroughly logical evolutionary thinking” might “force” us to conclude provides a clue to the answer. Think for a moment about science and logic themselves. Natural selection operates on a need-to-know basis. Between two individuals — one disposed to use scarce resources and finite capacities to seek out the most urgent and useful information and the other, heedless of immediate and personal concerns and disposed instead toward pure, disinterested inquiry, following logic wherever it might lead — it is clear which natural selection would tend to favor.

And yet, Darwinian skeptics about morality believe, humans somehow have managed to redeploy and leverage their limited, partial, human-scale psychologies to develop shared inquiry, experimental procedures, technologies and norms of logic and evidence that have resulted in genuine scientific knowledge and responsiveness to the force of logic. This distinctively human “cultural evolution” was centuries in the making, and overcoming partiality and bias remains a constant struggle, but the point is that these possibilities were not foreclosed by the imperfections and partiality of the faculties we inherited. As Wittgenstein observed, crude tools can be used to make refined tools. Monkeys, it turns out, can come surprisingly near to objective science.

We can see a similar cultural evolution in human law and morality — a centuries-long process of overcoming arbitrary distinctions, developing wider communities, and seeking more inclusive shared standards, such as the Geneva Conventions and the Universal Declaration of Humans Rights. Empathy might induce sympathy more readily when it is directed toward kith and kin, but we rely upon it to understand the thoughts and feelings of enemies and outsiders as well. And the human capacity for learning and following rules might have evolved to enable us to speak a native language or find our place in the social hierarchy, but it can be put into service understanding different languages and cultures, and developing more cosmopolitan or egalitarian norms that can be shared across our differences.

Within my own lifetime, I have seen dramatic changes in civil rights, women’s rights and gay rights. That’s just one generation in evolutionary terms. Or consider the way that empathy and the pressure of consistency have led to widespread recognition that our fellow animals should receive humane treatment. Human culture, not natural selection, accomplished these changes, and yet it was natural selection that gave us the capacities that helped make them possible. We still must struggle continuously to see to it that our widened empathy is not lost, our sympathies engaged, our understandings enlarged, and our moral principles followed. But the point is that we have done this with our imperfect, partial, us-ish native endowment. Kant was right to be impressed. In our best moments, we can come surprisingly close to being moral monkeys. Fist tap Dale.

women's role in holocaust significant

NYTimes | The Nazi killing machine was undoubtedly a male-dominated affair. But according to new research, the participation of German women in the genocide, as perpetrators, accomplices or passive witnesses, was far greater than previously thought.

The researcher, Wendy Lower, an American historian now living in Munich, has drawn attention to the number of seemingly ordinary German women who willingly went out to the Nazi-occupied eastern territories as part of the war effort, to areas where genocide was openly occurring.

“Thousands would be a conservative estimate,” Ms. Lower said in an interview in Jerusalem last week.

While most did not bloody their own hands, the acts of those who did seemed all the more perverse because they operated outside the concentration camp system, on their own initiative.

Ms. Lower’s findings shed new light on the Holocaust from a gender perspective, according to experts, and have further underlined the importance of the role of the lower echelons in the Nazi killing apparatus.

“In the dominant literature on perpetrators, you won’t find women mentioned,” said Dan Michman, the chief historian at Yad Vashem, the Holocaust Martyrs’ and Heroes’ Remembrance Authority in Jerusalem.

Ms. Lower, 45, presented her work for the first time at this summer’s workshop at Yad Vashem’s International Institute for Holocaust Research. She has been trying to decipher what motivated these women to commit such crimes.

“They challenge so deeply our notion” of what constitutes normal female behavior, she said. But the Nazi system, she added, “turned everything on its head.”

conservative drivers

Video - Shoot the gap!!!

a universe of us

NYTimes | We think of ourselves as individuals — perhaps, in philosophical moments, as the merger of body and soul. Most of us are barely aware of the estimated 10 trillion individual cells that make up the human body or of the 100 trillion or more bacteria that live collaboratively and benignly within and upon us. Whatever else we are, we are also a complex ecosystem, a habitat.

Scientists now have discovered another realm within our habitat — the virome, a large community of viruses. These are not the viruses that make us sick. These are an integral part of the microbiotic universe that makes us healthy.

In a recent paper in Nature, a team led by Jeffrey Gordon, a microbiologist at Washington University, reports that each of us has, so to speak, a viral identity — a pattern of viral DNA that is highly stable and highly distinct, even among closely related humans. This is unlike bacterial communities, which tend to evolve over time and to be similar among family members.

This discovery is part of a rapidly growing interest in the microbiome — an effort to understand the diversity and complexity of the trillions of organisms living within each of us. The basic exploratory technique is broad-scale DNA sequencing of the genetic contents of the human gut. The result is a significantly different view of who we are.

We are not just the expression of an individual human genome. We are, as Dr. Gordon writes, “a genetic landscape,” a collective of genomes of hundreds of different species all working together — in ways that leave our minds mysteriously free to focus on getting our bodies to the office and wondering what’s for lunch.

drug barons threaten rain forest

NYTimes | A recent State Department report said that “entire regions of Guatemala are now essentially under the control” of drug trafficking organizations, mainly the Mexico-based Zetas. Those groups enjoy a “prevailing environment of impunity” in “the northern and eastern rural areas” of Guatemala, the report said.

The drug organizations have bought vast cattle ranches in the Petén to launder drug profits, as well as to conceal a trafficking hub, including remote, jungle-shrouded landing strips. Cattle ranching in the Petén has quadrupled since 1995, with herds totaling 2.5 million cattle, according to Rudel Álvarez, the region’s governor.

“Organized crime and drug traffickers have usurped large swaths of protected land amid a vacuum left by the state, and are creating de facto ranching areas,” Mr. Álvarez said. “We must get rid of them to really have conservation.”

Deforestation has led to soil erosion at Yaxchilán, a Mayan city across the border in Mexico, which in turn has swollen rivers that erode limestone temples, said Norma Barbacci, regional director for the World Monument Fund. Ash from the squatters’ burns to clear fields for planting cause acid rain that wears at temples.

Fires, tree poaching and ranchers are encroaching in parts of the Laguna del Tigre national park in the western part of the reserve, threatening a sanctuary for 250 endangered scarlet macaws, the country’s last, said Roan McNab, country director for the Wildlife Conservation Society. Jaguars, crocodiles, river turtles and monkeys are also losing their habitat, he said.

The road to El Mirador, a five-day mule trek from the town of Carmelita that involves occasional bushwhacking with a machete, passes countless ditches where looters have ripped out Mayan graves. A wild toucan rockets down and then disappears off into the canopy. The remote dirt road that leads to the reserve is lined with newly razed cattle ranches, and the persistent buzz from a logging company drowns out the rain forest’s more subtle cacophony.

A local trail guide, galumphing along ancient limestone freeways buried beneath the forest, chain-smokes marijuana cigarettes rolled in notebook paper.

This rapidly deforesting mini-narco-state is a far cry from President Colom’s vision of a lush Mayan-themed vacationland.

preachers ALWAYS trying to set folk back....,

NYTimes | How black voters in California decide on Proposition 19, which would allow anyone 21 and over to possess up to an ounce of marijuana, could be critical to its success or failure. (At the moment, possession of more than 28.5 grams of marijuana, about an ounce, is punishable in most cases by up to six months in prison and a $500 fine.)

Blacks make up less than 10 percent of the population in California, but unlike two larger minority groups in the state where opinions on the measure are also split — Asians and Latinos — their “participation in elections is on par with their populations,” according to the California Voter Foundation, a nonprofit group here.

In the case of Proposition 19 — which is trailing narrowly in a recent Field Poll — appeals to that potential swing bloc have already begun, and the measure’s backers have been seeking out the support of prominent black leaders. Last week, proponents secured what they view as a major endorsement, that of Dr. Joycelyn Elders, the former United States surgeon general and the first black to hold that position.

In a statement to be published in a voter guide, Dr. Elders said the legalization bill would help divert law enforcement resources to more serious threats. “We can let police prevent violent crime, or we can accept the status quo, and keep wasting resources sending tens of thousands of nonviolent marijuana consumers — a disproportionate number who are minorities — to jail,” Dr. Elders wrote.

Kamala D. Harris, the San Francisco district attorney, who is black, joined the opposition last week. Ms. Harris, who is running for state attorney general, issued a statement saying that the proposition would encourage “driving while high” and drugs in the workplace.

Enforcement of marijuana possession laws is a touchy topic among many blacks here and nationwide.

This month, the Drug Policy Alliance — a New York group that is supporting Proposition 19 — released a study showing that blacks were arrested for possession at far higher rates than whites in California’s 25 largest counties, often two or three times higher. In those 25 counties, blacks make up 7 percent of the population but accounted for 20 percent of the marijuana possession arrests; in Los Angeles County, which accounts for about a quarter of the state’s population, blacks were arrested for marijuana possession at three times the rate of whites.

At the moment, 1,515 people are in California prisons on marijuana charges, 750 of them black, state corrections officials say.

The study’s author, Harry G. Levine, a professor of sociology at Queens College who has discovered similar trends in marijuana arrests in New York City, said that the impact of those arrests could be profound.

“A criminal record lasts a lifetime,” Mr. Levine wrote. “The explosive growth of criminal record databases, and the ease with which those databases can be accessed on the Internet, creates barriers to employment, housing and education for anyone simply arrested for drug possession.”

Rob MacCoun, a professor of law and public policy at the University of California, Berkeley, who has studied marijuana use in America, said there was little doubt that blacks — particularly black men — bore the brunt of arrests for marijuana.

“The arrest statistics are disproportionate with respect to African-Americans and disproportionate with respect to use,” said Mr. MacCoun. “And that’s very hard to justify in any way.”