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Did Humans Once Live by Beer Alone? An Oktoberfest Tale

By Lina Zeldovich

In October of 1953, the farmers of the Western hemisphere were busy toiling over harvested grain, either milling it into flour or prepping it for brewing. Meanwhile, a group of historians and anthropologists gathered to debate which of these two common grain uses humans mastered first—bread or beer?

The original question posed by Professor J. D. Sauer, of the University of Wisconsin’s Botany Department, was even more provocative. He wanted to know whether “thirst, rather than hunger, may have been the stimulus [for] grain agriculture.” In more scientific terms, the participants were asking: “Could the discovery that a mash of fermented grain yielded a palatable and nutritious beverage have acted as a greater stimulant toward the experimental selection and breeding of the cereals than the discovery of flour and bread making?”

Interestingly, the available archaeological evidence didn’t produce a definitive answer. The cereals and the tools used for planting and reaping, as well as the milling stones and various receptacles, could be involved for making either the bread or the beer. Nonetheless, the symposium, which ran under the title of Did Man Once Live by Beer Alone?, featured plenty of discussion.

The proponents of the beer-before-bread idea noted that the earliest grains might have actually been more suitable for brewing than for baking. For example, some wild wheat and barley varieties had husks or chaff stuck to the grains. Without additional processing, such husk-enclosed grains were useless for making bread—but fit for brewing. Brewing fermented drinks may also have been easier than baking. Making bread is a fairly complex operation that necessitates milling grains and making dough, which in the case of leavened bread requires yeast. It also requires fire and ovens, or heated stones at the least.

On the other hand, as some attendees pointed out, brewing needs only a simple receptacle in which grain can ferment, a chemical reaction that can be easily started in three different ways. Sprouting grain produces its own fermentation enzyme—diastase. There are also various types of yeast naturally present in the environment. Lastly, human saliva also contains fermentation enzymes, which could have started a brewing process in a partially chewed up grain. South American tribes make corn beer called chicha, as well as other fermented beverages, by chewing the seeds, roots, or flour to initiate the brewing process.

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But those who believed in the “bread first, beer later” concept posed some important questions. If the ancient cereals weren’t used for food, what did their gatherers or growers actually eat? “Man cannot live on beer alone, and not too satisfactorily on beer and meat,” noted botanist and agronomist Paul Christoph Mangelsdorf. “And the addition of a few legumes, the wild peas and lentils of the Near East, would not have improved the situation appreciably. Additional carbohydrates were needed to balance the diet… Did these Neolithic farmers forego the extraordinary food values of the cereals in favor of alcohol, for which they had no physiological need?” He finished his statement with an even more provoking inquiry. “Are we to believe that the foundations of Western Civilization were laid by an ill-fed people living in a perpetual state of partial intoxication?” Another attendee said that proposing the idea of grain domestication for brewing was not unlike suggesting that cattle was “domesticated for making intoxicating beverages from the milk.”

In the end, the two camps met halfway. They agreed that our ancestors probably used cereal for food, but that food might have been in liquid rather than baked form. It’s likely that the earliest cereal dishes were prepared as gruel—a thinner, more liquidy version of porridge that had been a Western peasants’ dietary staple. But gruel could easily ferment. Anthropologist Ralph Linton, who chose to take “an intermediate position” in the beer vs. bread controversy, noted that beer “may have resulted from accidental souring of a thin gruel … which had been left standing in an open vessel.” So perhaps humankind indeed owes its effervescent bubbly beverage to some leftover mush gone bad thousands of years ago.

The post Did Humans Once Live by Beer Alone? An Oktoberfest Tale appeared first on JSTOR Daily.

The Controversial Core of the Clean Water Act

By James MacDonald

By all accounts the Clean Water Act (CWA), the preeminent federal law protecting water quality in the United States, has been highly successful. The 1972 law has been periodically amended, but the gist is that it limits pollution into surface waters of the U.S. through restrictions and permit requirements. The act does not directly regulate drinking water. Now the Trump administration wishes to significantly weaken the CWA by limiting its jurisdiction, a move cheered by some but bemoaned by many others. Nevertheless, according to April Collaku in Fordham Environmental Law Review, this question of exactly which waters are covered by the CWA is not new.

Upon enactment of the CWA, federal agencies charged with its enforcement saw the law as covering discharges in the “navigable waters of the United States,” which on the face of it sounds like any water that can hold a boat. The reality is more complicated. The CWA itself, in fact, defines navigable waters as “waters of the United States,” which sounds like all water everywhere under U.S. jurisdiction.

Given the ambiguity, this definition has repeatedly found itself under court review. The courts struggled to reconcile the “waters of the United States” language with “navigable waters,” roughly defined as waters used for commerce or travel. Courts have generally expanded that definition to include tributaries of those navigable bodies and wetlands that are adjacent or connected to those navigable bodies.

The rules the current administration is seeking to override stem from a 2006 Supreme Court Decision. The decision, known as Rapanos v. United States, left the exact scope of the CWA muddled, with some justices arguing for the expanded navigable waters definition above and others limiting jurisdiction only to permanent bodies of water.

To help end the confusion, during the Obama administration the EPA decided to spell out a clear definition of waters of the United States. The definition closely hews to the expanded definition of navigable waters, but specifies all tributaries and adjacent waters that have a “significant nexus” to navigable waters. This expanded definition included a lot more wetlands, as now wetlands adjacent to tributaries were also included. Certain seasonal streams and wetlands were included under this final definition as well.

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This expansion provided clarification but also controversy. The newly covered waters often came into conflict with private property. Some farmers and business interests found themselves occasionally limited in what crops they could plant, or what practices they could follow, next to what they saw as unimportant streams or wetlands.

Now the controversy rolls on, as under the Trump administration, most tributaries and adjacent wetlands will be stripped of CWA protection. Opponents fear that increased pollution will inevitably cause downstream harm. One side effect of the rule reversal is that the CWA is once again operating without a firm definition. More confusion and lawsuits are inevitable.

Editors’ Note: An earlier version of this article stated that the Supreme Court Decision Rapanos v. United States was decided in 2015; in fact it was decided in 2006.

The post The Controversial Core of the Clean Water Act appeared first on JSTOR Daily.

climate hope

By ayjay

At the end of this interview, the environmental historian Jason Moore says, “Capitalism … had its social legitimacy because in one way or another it could promise development. And I don’t think anyone takes that idea seriously anymore.” Which is a very strange thing to say indeed, because economic development is the one promise that capitalism has delivered on, and massively. (This is the chief burden of the books by Deirdre McCloskey that I wrote about here and here.) In fact, and quite obviously, economic development around the world is the chief reason we have a climate crisis, because that development has ravaged our environment — and the global nature of modern capitalism means that that ravaging has been dispersed over the entire globe.

Moore agrees with my friend Wen Stephenson that nothing serious can be done to avert the oncoming climate catastrophe except a world-wide political/economic revolution. Stephenson:

The sheer depth, scale, and speed of the changes required at this point are beyond anything a mere climate movement can possibly accomplish, because such a movement is inherently unsuited to the nature of the task we face: radically transforming the political-economic system that is driving us toward climate breakdown. Given the sclerotic system in which the Green New Deal — the only proposal ever put before Congress that confronts the true scale and urgency of the climate catastrophe — is dead on arrival, mocked even by the Democratic Speaker of the House, the pretense that anything less than revolutionary change is now required amounts to a form of denial.

I am skeptical about this proposal for two reasons:

  1. The revolution would have to be global, because if it happens only in Europe or North America, or both, then global capital will simply shift its attentions and energies to other parts of the world, East and South (which is already where most of the depredations of the environment are happening). But a single, ideologically unified, worldwide political revolution is simply unimaginable.
  2. I see absolutely no reason to believe that any socialist government, local or global, will implement the changes needed to slow climate change. Socialism has a uniformly terrible record in these matters, from the Soviet Union to Chavez’s Venezuela — totally dependent for its social stability on global petrocapitalism — to this little country you may have heard of called China. I strongly suspect that that pattern will continue: when socialist policies throw a spoke into the engine of commerce, and the economy starts to collapse so that there’s less and less wealth to distribute, then socialist governments, like all others, will not hesitate to exploit the environment to become more productive. (Or will become state-capitalists like the Chinese Communist Party.)

Where does that leave us? Well, you can offer a counsel of despair, as Jonathan Franzen does. Now, he says he doesn’t despair:

If your hope for the future depends on a wildly optimistic scenario, what will you do ten years from now, when the scenario becomes unworkable even in theory? Give up on the planet entirely? To borrow from the advice of financial planners, I might suggest a more balanced portfolio of hopes, some of them longer-term, most of them shorter. It’s fine to struggle against the constraints of human nature, hoping to mitigate the worst of what’s to come, but it’s just as important to fight smaller, more local battles that you have some realistic hope of winning. Keep doing the right thing for the planet, yes, but also keep trying to save what you love specifically — a community, an institution, a wild place, a species that’s in trouble — and take heart in your small successes. Any good thing you do now is arguably a hedge against the hotter future, but the really meaningful thing is that it’s good today. As long as you have something to love, you have something to hope for.

But this is frankly to admit that all the victories are short-term and small-scale. Franzen tries not to think about what’s happening in the longer term and on the global scale.

Does anything remain? Possibly: technological fixes. Any potential fixes are fraught with uncertainty and danger, but more and more scientists are quietly hinting that they just may be our last resort. But why are those scientists being so quiet in their hinting? Largely because almost every climate activist I know of is absolutely and unremittingly hostile to any such proposals. Like my suspicions about global socialist revolution, their suspicions about technological fixes come in two varieties. The first is straightforward and reasonable: Why would we trust the very technocracy that got us into this mess to get us out?

The second one, though, is a little more complicated. I think that many climate activists hate the very idea of technological fixes because if they should happen to work that would mean that the bastards got away with it. That is, if the global capitalist elite that has soo cheerfully and brazenly and heedlessly destroyed the natural world should, at the last moment, pull a technological rabbit out of their technocratic hat that stops the worst from occurring, that would feel like the biggest miscarriage of justice ever, because a group of people who have a very strong claim to the title of Greatest Criminals in History would walk away scot-free and indeed might even be thought of as heroes. It offends one’s sense of justice so profoundly that it’s hard to root for such technological fixes to work, even if they could indeed avert the worst consequences of capitalist exploitation of the planet.

But a planet saved is better than a planet ruined. Even if in the saving the Greatest Criminals walk free.

So I am thinking a lot about the various technological means of addressing climate change. I’m looking for actions less dangerous than the great big global fixes that some of the more imaginative technocrats propose, but that also would have, at least potentially, far greater effects than the strictly local actions that Franzen recommends. Ideas in this post seem to come in twos, so here are two very promising ideas:

The first involves making plants a little better at holding carbon dioxide:

Chory believes the key to fixing that imbalance is training plants to suck up just a little more CO2, and to keep it longer. She is working on engineering the world’s crop plants to have bigger, deeper roots made of a natural waxy substance called suberin — found in cork and cantaloupe rinds — which is an incredible carbon-capturer and is resistant to decomposition. By encouraging plants to have bigger, deeper, more suberin-rich roots, Chory can trick them into fighting climate change as they grow. The roots will store CO2, and when farmers harvest their crops in the fall, those deep-buried roots will stay in the soil and keep their carbon sequestered in the dirt, potentially for hundreds of years.

The second would turn air conditioners into carbon-capture machines:

A paper published Tuesday in the Nature Communications proposes a partial remedy: Heating, ventilation and air conditioning (or HVAC) systems move a lot of air. They can replace the entire air volume in an office building five or 10 times an hour. Machines that capture carbon dioxide from the atmosphere — a developing fix for climate change — also depend on moving large volumes of air. So why not save energy by tacking the carbon capture machine onto the air conditioner?

Let a thousand such flowers bloom — a thousand ways to address our changing environment that are technologically feasible and highly scalable but do not require the complete transformation of the whole human order. Keep those ideas coming, scientist friends. We desperately need them.

How Ken Liu Translates, and Why He Writes

Ken Liu is a celebrated author of American speculative fiction and a pathbreaking translator of Chinese science fiction into English. He has won the ...

The post How Ken Liu Translates, and Why He Writes appeared first on Public Books.

How Natural Gas Helped Make our Industrial World

By Eric Schewe

The natural gas industry is enjoying a renaissance, thanks to the widespread adoption of fracking around the country in the past fifteen years. In that time, domestic production of natural gas has increased around 50%. Natural gas now accounts for 1/3 of the energy produced in the United States, more than any other source. Until recently, natural gas was billed as the “green” fossil fuel. Compared to coal or petroleum products, burning methane gas (CH4) releases less carbon into the atmosphere to produce the same energy, but it does still release harmful emissions. 

Coal and gasoline have earned their reputation as fossil fuel boogeymen. Both have played extremely visible roles as the principal feedstocks for electricity generation and automobiles, respectively. But, scholar Leslie Tomory writes, methane gas was actually the first fuel to be delivered in an integrated network that provided hydrocarbon energy to the masses at the flip of a switch, back in Regency-era London. In the process, the Gas Light and Coke Company (GLCC) confronted and solved problems of industrial politics, time coordination, machine standardization, contractor management, and even customer relations that have often been attributed to the later railway or electricity industries.

Founded in 1812, the Gas Light and Coke Company (GLCC) produced coal gas. The company heated coal in large vessels (“retorts”) inside ovens that forced out its gases and other impurities (such as sulfur) to produce coke. The expanding steel industry needed the purified carbon in coke to make high-quality steel. GLCC was the first company to store the released methane gases and to offer it for lighting in homes, businesses, and for street lamps.

Aside from a few local water supply networks, nothing of the scale had ever been attempted. Even the company’s political position was new, straddling private and public concerns. In exchange for papers of incorporation, GLCC agreed to install and fuel street lamps at low prices. In practice, this encouraged localities to agree to let the company tear up the streets to lay pipe.

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GLCC intended only to provide gas from 4:00 pm to 10:00 pm, but the demand for the gas was high. Before the invention of gas meters, customers could pay a flat fee but then use the gas all night. Some widened their valves to make the gas brighter or even stored the gas illegally. The company responded by improving their generating capacity, but also by regularly inspecting homes and requiring the use of standardized pipes, valves, and burners.

Methane gas has recently overtaken coal as the most common source of energy for electrical generation worldwide. Migrating toward renewable energy today requires solving many of the same problems that the early gas industry faced: storage, transmission, and most of all, politics. Because—unlike in the 1810s—renewable energy is attempting to displace a pre-existing complex energy infrastructure, backed by powerful interests, that has structured the world we see around us.

 

The post How Natural Gas Helped Make our Industrial World appeared first on JSTOR Daily.

The Sky’s Creepiest Parasites

By James MacDonald

Brood parasitism is a truly diabolical life strategy employed by certain birds, most famously cowbirds and cuckoos. Brood parasites make no nest of their own. Instead, they lay their eggs in another bird’s nest while the host bird is away. The impostor egg hatches, then often tosses all or some of the host eggs or babies out of the nest, killing them. The unsuspecting host parents dedicate their energy to raising the impostor chick. Oddly, they usually don’t seem to notice, no matter how significant the difference—as discussed by Oliver Krüger in Philosophical Transactions, cuckoos may lay eggs in nests of hosts up to six times smaller than they are. Sometimes, the chick dwarfs the hosts but the hosts diligently raise it anyway.

This sneak attack allows brood parasites to lay more eggs in one season than non-parasites, as they do not need to put any energy into building a nest or caring for offspring. The cost to the host, however, is enormous. They either waste energy caring for a parasitic egg, or in worst case the impostor kills every single host egg.

Hosts are not defenseless; brood parasites do not choose their victims randomly. Hiding nests better, for example, seems to be a deterrent in some cases, as does placing the nest so that there is no nearby place for a parasite to bide its time. Experience can help, in that young host birds are often more vulnerable. Sometimes the best defense is a good offense, many potential host species simply attack nearby brood parasites during breeding season. The downside, of course, is that while aggression may deter a parasite, it also lets the parasite bird know that a nest is near.

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Once a brood parasite successfully infiltrates a nest, astute hosts will notice and damage or kill the parasite egg. In some cases hosts will even abandon the entire nest rather than raise a parasite chick. Some potential hosts lay homogeneous clutches of eggs to make parasite eggs stand out. Others are able to tell if one egg is much larger; they will kill the large egg. A related strategy is to stop feeding any chick when its needs become too great.

According to Krüger, this parasite-host struggle has the hallmarks of a co-evolutionary arms race. As host birds develop counter-measures, parasites develop new techniques for duping the hosts. When host defenses become too effective, the parasites might even switch hosts. Neither side is threatening the other with extinction, so the arms race stalemate drags on.

The post The Sky’s Creepiest Parasites appeared first on JSTOR Daily.

AI: Machines or Magic?

AI has always only partially been about the actual future of probable developments and base-rate outcomes; it has also been singularly productive of philosophical speculation, fantasy, and arguments about ourselves and the future ...

The post AI: Machines or Magic? appeared first on Public Books.

The Environmental Downside of Cannabis Cultivation

By Lina Zeldovich

Thanks to the legalization of recreational cannabis in 10 states and the District of Columbia, sparking up a joint in these areas is as easy as ordering a glass of wine.

Spending on legal cannabis, which includes 33 states and the District of Columbia that allow medical cannabis use for conditions such as glaucoma, chronic pain, and the side effects of cancer treatments, topped $12 billion worldwide in 2018, according to industry analysts, and is expected to increase to $31.3 billion by 2022.

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With all that potential profit on the line, it’s no surprise there is growing interest in legalizing cannabis cultivation. California has issued around 10,000 cultivation permits. Between 2012 and 2016, the number of cannabis farms in the Golden State increased 58 percent and the number of plants increased 183 percent.

While much of the research has focused on public health and criminalization, the environmental implications of commercial-scale cultivation have been largely ignored. Could the increases in cannabis cultivation send the environment up in smoke?

New research has linked production of the once-verboten plant to a host of issues ranging from water theft and degradation of public lands to wildlife deaths and potential ozone effects.“We have a culture and history of cannabis cultivation in remote areas that may be sensitive to environmental disruptions,” explains Van Butsic, co-director of the Cannabis Research Center at the University of California Berkeley.

Worries over Water

In California, the water-hungry crop is often grown in remote, forested watersheds and requires almost 22 liters of water per plant a day during the growing season, which adds up to three billion liters per square kilometer of greenhouse-grown plants between June and October, according to some research. During the low flow period, irrigation demands for cultivation can exceed the amount of water flowing in a river, leaving little water to sustain aquatic life.

Some of the biggest environmental offenders are cultivators operating unpermitted farms on public lands. These “trespass grows” are often in national forests or on tribal lands where water is diverted from streams to irrigate acres of plants. In 2018, there were an estimated 14,000 trespass grows on federal and private lands in Humboldt County, California, alone.

Satellite image of cannabis farms in the forest in Humboldt County. Courtesy of the UC Berkeley Cannabis Research Center

At the Shasta-Trinity National Forest in California, a team from the Integral Ecology Research Center, or IREC, a nonprofit organization dedicated to wildlife conservation, removed more than five miles of irrigation lines that diverted more than 500,000 gallons of water per day to irrigate cannabis plants.

IREC co-director Mourad Gabriel notes that trespass grows are often located near headwaters and have disastrous downstream effects. For example, streams in Mendocino, California, often run dry during the summer when growers are diverting water, decimating populations of Coho salmon and steelhead trout. “These are drug trafficking organizations looking to profit off of our natural resources,” says Gabriel.

War on Wildlife

Unpermitted growers wanting to avoid detection often choose public and tribal lands as prime places to hide their operations. These locations are also pristine wildlife habitats.

The cultivation sites also interfere with the restoration of distressed habitats. Local environmental groups complained that the grows overwhelmed their conservation efforts and, in some cases, disrupted ongoing restorations or made the work more dangerous, according to a 2018 study published in Humboldt Journal of Social Relations. The grows drained and polluted streams, degraded watersheds and killed wildlife.

Trespass grows, which use mass quantities of toxic rodenticides to keep rodents from chewing on irrigation lines, have been linked to the deaths of fish, birds, and mammals. One study found that 79 percent of dead fishers—small carnivorous mammals, collected in California between 2006 and 2011—had been exposed to pesticides at trespass grow sites. The rate continues to increase, according to Gabriel. Mule deer, gray foxes, coyotes, northern spotted owls and ravens have also been victims of poisoning, linked to cannabis cultivation.

Rodenticide wired to a snap-trap beneath marijuana plants. Image courtesy Mourad Gabriel at IERC.
Rodenticide wired to a snap-trap beneath marijuana plants. Image courtesy Mourad Gabriel at IERC.

“The amount of fertilizers and pesticides we find on one half-acre [of illegal] cultivation plot could be [used on] 1,000 acres of corn—and wildlife are paying the price,” Gabriel says.

Pollution Problems

It’s not just trespass grows causing environmental issues. Since Colorado stores started legally selling recreational cannabis in 2014, emissions from the 600-plus licensed cultivation facilities in Denver have sparked concerns over air pollution.

William Vizuete, associate professor at the University of North Carolina’s Gillings School of Public Health, is working on an air quality model to better understand how commercial cannabis cultivation could affect the atmosphere. His research showed that cannabis plants produce volatile organic compounds or VOCs that can produce harmful pollutants.

“If plants produce VOCs, there is a high possibility that under certain conditions, cannabis cultivation could impact the ozone,” Vizuete explains.

Cannabis emits potent VOCs called terpenes that, when mixed with nitrogen oxide and sunlight, form ozone-degrading aerosols. In a high desert zone like Denver, where normally there are few sources of VOCs, any new source of such pollutants will likely lead to ground-level ozone production, Vizuete notes. He worries that the significant numbers of cannabis plants being grown will become the regular source of VOCs, exacerbating the issue by combining with the manmade nitrogen oxide spewed from the many cars in that urban environment. Vizuete worries that the significant numbers of cannabis plants being grown in an urban area could exacerbate the issue. (High concentrations of VOCs have been linked to a range of human health issues, from nausea and fatigue to liver damage and cancer).

To test the potential effects, Vizuete grew four strains of cannabis (from among the 600-plus strains available in Colorado): Critical Mass, Lemon Wheel, Elephant Purple, and Rockstar Kush—for 90 days and measured the terpenes at each stage of growth. The results showed that in Denver, assuming a concentration of 10,000 plants per cultivation facility, cannabis could more than double the existing rate of annual VOC emissions to 520 metric tons and produce 2,100 metric tons of ozone.

Vizuete believes his estimates might be conservative, explaining, “We picked four [cannabis] strains based on their popularity, and their VOC emissions might not be representative all of the strains. Additionally, in commercial facilities, where conditions are optimized for growth, emissions may be even higher.”

Legalization Could Close Environmental Loopholes

Regulating the production of cannabis can address many of the environmental issues associated with its cultivation, argues Jennifer Carah, senior scientist in the water program at The Nature Conservancy of California.

In California, where up to 70 percent of legal cannabis is grown, the California Department of Food and Agriculture regulates the licensure process but many counties and municipalities also have the authority to grant cultivation licenses and, Carah says, the regulations are highly variable. Plus, the black market for cannabis still exists. It’s more expensive to purchase legal cannabis than to buy it on the black market, plus not all growers are willing to go through the due process to become legal.

“The black market is not going away,” Carah admits, “but to the degree that we can entice growers into the legal market, their agricultural practices can be regulated like other agricultural crops, which will go a long way to addressing potential environmental impacts.”

Recently, legalization has put a dent in the number of trespass grows. Illicit cultivation in Oregon forests decreased following legalization.

Some states have established environmental regulations for cannabis growers. California Water Boards require permitted growers to register water rights and follow strict guidelines that include prohibitions on diverting surface water from April to October and irrigating with stored water during the dry season—regulations not imposed on other California-grown crops. In Washington State, the Puget Sound Clean Air Agency requires growers to submit information about their plans for monitoring and controlling air pollution.

Butsic of UC Berkeley argues that federal legalization would also provide new funding opportunities through organizations such as the National Science Foundation and Environmental Protection Agency to allow researchers to assess environmental risks and develop solutions.

From a pollution perspective, federal legalization could set emissions standards.

“There are lots of technologies that capture VOCs before they enter the atmosphere that are required in other industries like gas stations,” Butsic explains. “Before [emissions] standards can be set for cannabis, we need recognition of the issue and long-term data to develop regulatory statutes—and we’re a long way from that because federal prohibition has hindered research and we don’t have the science yet.”

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Machine Learning Is a Co-opting Machine

We are using human activity as an example from which to learn, and that becomes the basis upon which we then develop automated solutions to all sorts of ...

The post Machine Learning Is a Co-opting Machine appeared first on Public Books.

How Families with Two Dads Raise Their Kids

By Benjamin Winterhalter

Some states, including Texas, South Dakota and Alabama, have tried to defy the 2015 Supreme Court ruling that made marriage equality the law of the land. Their “religious freedom” bills allow taxpayer-funded agencies to deny qualified LGBTQ adults to foster and adopt children.

LGBTQ protection in education appears limited as well. When pressed on the question, Education Secretary Betsy DeVos is refusing to tell lawmakers whether she believes the federal government should include “sexual orientation” and “gender identity” in anti-discrimination policies.

That reminds me of how former Kentucky family court judge W. Mitchell Nance refused to hold hearings on same-sex couples’ adoptions in 2017 “as a matter of conscience.” He resigned after his state’s Judicial Conduct Commission found him guilty of misconduct.

Maybe any officials, judges and lawmakers who are alarmed by dual-dad or dual-mom households should check out the research on how gay parents differ from straight parents. So far, most of this scholarship has focused on the social, emotional and cognitive outcomes of children they raise. (Spoiler alert: These kids turn out fine.)

As a former teacher who now researches gay dads and their families, I’m studying how the growing number of men married to other men are raising their children. So far, I’m finding few differences between them and their straight peers of similar socioeconomic status – especially regarding their children’s schooling.

A Growing Population

Since the Census Bureau estimates – but does not count – the number of households headed by two fathers, it’s hard to track them.

Plans are taking shape for the Census Bureau to begin counting same-sex couples who share a household in 2020, although the agency won’t be counting all LGBTQ individuals.

Nevertheless, the American Community Survey, the Census Bureau’s ongoing demographic survey of approximately 3 million households, already follows same-sex parenting. It estimates that in 2017, almost 40,000 two-dad households were raising children, up from about 30,000 in 2010.

Parenting Roles

How do parents in these families settle into specific roles? In short, just like heterosexual parents do.

Research suggests that affluent, white, two-father households adhere to traditional parenting roles. One is the primary breadwinner, while the other earns either less income or none at all and handles most of the caregiving and chores.

However, two-dad households can challenge the 1940s Norman Rockwell image of gendered parenting – just like heterosexual couples can.

Households with two fathers working full-time rely on day care facilities, babysitters, housekeepers and nearby relatives for support. Some of these men even take on responsibilities based on skills and strengths, rather than who fits the socially and culturally constructed mold of being more “motherly” or “fatherly.”

Community and School Engagement

And that’s where the parenting of gay dads may differ from a traditional heterosexual household, as my research and the work of other scholars suggests.

While interviewing and spending time with 22 gay-fathered families living in the Northeast, I have learned that they’re apt to step up. But it depends on where dads live. Many living in more gay-friendly areas become involved as classroom parents, voluntarily assisting teachers, reading books or leading singalongs. Some take leadership roles by becoming active PTA members or organizing events that go beyond their children’s classes. In some cases, gay fathers become PTA presidents or serve on school boards.

Like all civically engaged parents, gay fathers support their local museums and libraries and enroll their kids in camps and extracurricular activities. They sometimes do additional volunteer work for social justice groups.

Dads living in less gay-friendly areas want to have more school-based presence, but concerns about their children’s and family’s safety have made it challenging.

The largest-scale survey to date was conducted in 2008 by the Gay Lesbian Straight Education Network, an organization focused on the safety of LGBTQ students in schools. That study, which included 588 LGBTQ parents, suggested that gay fathers could be more likely to be involved in school-based activities than heterosexual dads.

Aside from the simple fact that they love their children just like all parents do, Abbie Goldberg, a Clark University researcher, and her colleagues have shown that increased presence may be due, in part, to fathers’ initiatives to counter bias and assert more same-sex visibility and inclusion in schools. My current study indicates the same. Many of the men taking part have told me that being actively involved helps them preemptively counteract potential negative encounters with school personnel and other families.

Gay dads prefer schools and communities that are safe and inclusive. As my research suggests, living in a inclusive community makes them more likely to engage. Beyond that, they want lawmakers bent on barring them from fatherhood to see that two-dad families are for the most part just like any other family.


This article is republished from The Conversation under a Creative Commons license. Read the original article.

The Conversation

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Workplace Burnout is Nothing New

By Farah Mohammed

“Neurasthenia” was once the diagnosis used to refer to a spectrum of symptoms, from fatigue to depression to anxiety. Also called nervous exhaustion, nerve deficiency, or nerve weakness, it was a burgeoning problem when the term was popularized by neurologist George Miller Beard in 1869. He didn’t characterize it as a curable disease, but as a distress signal from a brain assailed with and overcome by the hefty demands of a fast-paced, urban life. (The condition was also called “Americanitis.”) Now we call that special melange of exhaustion and hopelessness resulting from chronic stress “burnout,” and it’s the scourge of workplaces everywhere.

In 1909, the British Medical Journal ran a commentary on the multiple manifestations of neurasthenia across the population, writing, “Doctors have daily opportunities of observing the steady spread of neurasthenia.”

They describe students who become “victims of intellectual overwork,” and list their complaints (familiar to anyone under the pressure of today’s demanding curriculums): headaches, sleeplessness, an inability to concentrate. The write, “they are haunted by fear of the examinations which loom before them like spectres.”

In other cases, they describe what sounds like what we might label generalized anxiety: “Other neurasthenics are shy to the extent of becoming paralysed before the simplest demands of social life.”

In the workplace, neurasthenia would show itself in an unstable and unhappy work pattern, which today might be viewed as passion, eccentricity, or merely just a particular working style. But in 1909, “hustling” was viewed as the warning sign of a short-circuiting coping system:

In professional life neurasthenia shows itself in over-eagerness to succeed by short and often questionable cuts, in alternating paroxysms of exaltation and depression ; in oversensitiveness to criticism, which reveals itself in a tendency to rush into controversy about things that do not matter; and in premature breakdown. In business it shows itself in “hustling”; every one is in a hurry either to make money or fame, or both.

The writer gives other examples we’d recognize today, including a growing cultural focus on themes of “adultery, suicide and neurosis,” and increasing prevalence of people acting in ways that are “violent, passionate, impulsive, with little or no power of self-restraint; this is the class by which the crime passionel is looked upon as not only justified but as a virtuous deed.”

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Today, we may lament about how stressed we are and how hard our students work. Perhaps as a culture we are beginning to see the profound danger in pushing ourselves constantly to the limits. After all, the World Health Organization recently added “burnout” to its official handbook of diseases. Still, on an individual level we tend to secretly revel in our busyness and anxiety.

The British Medical Journal article, on the other hand, expresses a genuine terror as to where this madness may lead. “Ancient Rome was brought to ruin by neurasthenia, which sapped the tough old stock and left it an easy prey to barbarians,” writes the author. “Social observers have noted in us today most of the signs of decay that were visible when Imperial Rome was tottering to its fall.”

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Why Tornadoes Are So Difficult to Predict

By James MacDonald

The central United States is now recovering from a string of deadly tornadoes: at least 225 over twelve days. The good news is that the long streak of frequent tornadoes is over for now. The bad news is that in much of North America’s most tornado-prone areas, tornado season still has a few months to go. Crucial to saving lives are the warnings and drills familiar to school children in risky areas. But despite more than a century of trying to predict tornadoes and understand their behavior, the average advanced warning is still only fourteen minutes— just enough time to take immediate cover. How do tornadoes form? Why are they so difficult to predict?

Tornadoes are not complete mysteries, according to atmospheric scientist Robert Davies-Jones. For example, it’s known that tornadoes almost invariably form inside “supercell” thunderstorms, rather than fronts or chains of storms.

Supercell storms are characterized by drastic differences in temperature and windspeed at different elevations. Enough heat near the ground will cause a rotating mass of warm, wet air to move up across an invisible boundary into a layer of cooler, drier air. The warm air eventually rises high enough to cool, where it sinks and spreads out, forming what looks like an anvil shape when viewed from the side. The drop in temperature releases rain, which increases the density of the clouds as the rotating updraft sinks back through the cooler, drier air.

The rotation moves rain and sinking air around to different parts of the storm, forming low level clouds and forcing air downward in some parts of the storm and up in others, intensifying the rotation. Where regular thunderstorms are more chaotic, with multiple updrafts and downdrafts acting constantly on one another, supercell storms only have a few major updrafts and downdrafts that can remain quite stable. Under these stable conditions, the rotation of the wind can continue to gain strength at low elevation and a tornado has the opportunity to form.

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Even with this understanding of how tornadoes form, however, predicting remains difficult. Just because conditions are favorable for tornadoes doesn’t mean they necessarily will, and even if one does form it’s hard to know if it will be weak or dangerously strong. Most supercell storms, while powerful phenomena in and of themselves, never spawn a tornado. Friction against the ground seems to provide the final ingredient for tornado formation, but it is still unclear exactly how and when all these pieces come together.

Even if all these pieces were known, a long-range prediction would still be a tall order. Conditions conducive to tornado formation are extremely specific. Once a dangerous storm has formed, radar can detect the vortex formation, giving the short-term warning present today. Regular weather prediction more than a few days in advance remains iffy. For now the best anyone can do is to pinpoint potentially dangerous storms.

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Losing the Night Sky

By James MacDonald

Gaze upwards on a clear night, and you might see a tiny bright spot moving in a slow, straight arc across the sky. One satellite is a minor addition to the starscape, but what happens as their numbers grow? Elon Musk and SpaceX have launched the first set of sixty satellites in Starlink, a web of what will eventually be thousands of satellites designed to provide internet to every corner of the globe. Astronomers fear that this constellation of satellites will soon obscure our view of the stars, disrupting research. It’s the latest salvo in a long war against light pollution.

As Jacob Hoerger writes in the New Atlantis, ever since the spread of electric lighting, light pollution has been a problem for astronomers and dreamers alike. Disruptions to nocturnal wildlife and possibly human health from artificial light have been examined, but the damage from light pollution is more fundamental. Hoerger provides frightening statistics. Even without the new satellites, most urban residents of industrialized countries cannot see major constellations; two-thirds of all Americans will never see the Milky Way. Some changes are physical: according to data from the late 1990s, 40% Americans will never experience darkness deep enough for their eyes to fully adjust. Lights from distant cities cast a glow in some of our remotest areas.

This especially affects astronomers. As early as the nineteenth century, astronomers began warning that astronomical phenomena were becoming more difficult to see. The spread of urban and suburban areas have affected storied observatories such as California’s Mount Wilson Observatory and Palomar Observatory. Not even a mountain range was enough to preserve the darkness for the Kitt Peak National Observatory near Tucson, Arizona. Light pollution effectively put an end to building new observatories in North America. Most new large telescopes are located in remote mountainous areas like Hawaii or Chile, to take advantage of altitude and darkness.

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As Hoerger notes, the problems of light pollution go beyond ruining the view. According to a 2010 estimate, the cost of wasted outdoor lighting adds up $7 billion a year in the United States. Light requires energy—and emissions— to produce. Therefore, light that is generated pointlessly is a significant contributor to climate change.

Nevertheless, progress is possible. In many areas, regulations protect wildlife such as sea turtles from disruptive lights, reducing excess light at for least part of the year. Astronomical research is a potent economic engine, so cities like Tucson have passed ordinances to reduce light pollution and protect this key industry. Increasing LED use reduces both energy costs. Dark sky preserves are becoming more common. Satellite developers have pledged to try to make satellites darker. But still, Hoerger suggests that the only thing that will truly spur regulators to act is humankind’s inherent sense of wonder.

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The Seal That Flew 1000 Miles To Get Home

By Lina Zeldovich

On March 19, 2019, several Bermuda locals found an unusual animal on Tobacco Bay Beach—a gray seal. Resting on the rocks, the seal appeared exhausted, with several lacerations on its flippers. The marine mammal was completely out of place in this subtropical island, so the locals sought help from the Bermuda Aquarium, Museum and Zoo (BAMZ), which rehabilitates sea turtles, birds, and other marine and terrestrial creatures.

Seals, however, are rare guests at the BAMZ, says Ian Walker, the organization’s principal curator and veterinarian. “There had been six recorded seals here since 1873,” he says. “They aren’t common in Bermuda at all.”

Gray seals are northern creatures found on both sides of the Atlantic Ocean. In North America, they live around Rhode Island and Connecticut, and farther up north in Nova Scotia. They are solitary creatures that usually swim alone, except during breeding seasons when they form groups.

The seal turned out to be a young female, later named Lou-Seal. How Lou-Seal ended up in Bermuda is a mystery. Walker says that as the climate changes, food sources fluctuate and seals may be following them. Currents change too, so as she was foraging, Lou-Seal may have been pulled into the wrong stream. “The Gulf Stream is constantly shifting in terms of eddies and currents, so it’s possible she got wrapped up in an eddy and ended up in the Gulf Stream,” he explains. “And then she managed to get across it, swam to the next landmass and ended up here. She was lucky to get here because there’s not a lot of land at this latitude, just Bermuda.”

During that long journey, Lou-Seal lost a lot of weight because there was little food she could eat. Gray seals feed on herring, cod, squid, and sand eels as well as other northern marine species, which don’t live in the subtropical waters. She was anemic, had a respiratory tract infection, and was so emaciated that for a while things didn’t look promising. Luckily, she was young and strong, Walker says. Thanks to antibiotics, abundant food, and good care from the BAMZ team, she got better.

At first, Lou-Seal was at ease with humans and followed them for food. As she got stronger she became more aggressive, which was a good thing, according to Walker. “We don’t want the seals to associate humans with food, because they get in trouble taking fish from the fishermen’s nets or swimming around boats in a harbor,” he explains. Seals have been known to infuriate fishermen by breaking their nets and stealing their catch. Years ago, a fisherman in Cape Elizabeth, Maine, was quoted as saying, “I believe seals should be dealt with as you would deal with rats.” Lou-Seal is better off not perceiving humans as friends, which is why Walker was happy to see her acting feisty. “It was a huge relief to me when she lunged for me!” he recalls. “At first I wasn’t sure she was going to make it in the wild—but that was a good sign.”

Now the BAMZ team had a new challenge: How could they get Lou-Seal home? Her native waters were 1,000 miles away and the Gulf Stream represented the natural barrier between Bermuda and her home shores.

Lou-Seal

Walker had previous experience with sending a stranded seal home on a FedEx plane. This time, he contacted Canadian company, Cargojet, which agreed to fly Lou-Seal to the United States for free. “They they were terrific to work with and agreed to fly at lower altitudes to compensate for Lou-Seal’s anaemia,” Walker says. He also contacted Mystic Aquarium in Connecticut, which has an animal clinic facility. Mystic offered to finish her rehabilitation until she was ready to return to sea. In the meantime, BAMZ built her a travel crate and Bermudian children decorated it with colorful marine artwork. “I accompanied the seal on the journey to Newark and she was transported by an all-female flight crew which seemed very fitting.” Walker says. “We also sent up a crate of Gosling’s Black Seal Rum,” he adds—so that the Mystic crew could toast to her release.

When Lou-Seal landed, Mystic’s stranding animal rescue vehicle was already waiting, and she was quickly taken to the rehabilitation clinic. She did well there, says Sarah Callan, assistant manager of Mystic’s animal rescue program. “She was eating about twenty pounds of fish a day and you could clearly see the difference in her appearance,” Callan says. “She was only 211 pounds when she came in, and she was 362 pounds at the end.” Like the BAMZ personnel, Mystic’s crew took precautions to avoid habituating her to humans, throwing Lou-Seal fish in such a way that she did not see them.

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On May 30, 2019, a crew of Mystic staff and volunteers released Lou-Seal into the ocean. When the crate was opened, she took some time to examine her surroundings, looking back and forth. “The last time she saw ocean water was on Bermuda,” Callan says, “so she took a couple of minutes to take it all in.” And then she hopped straight into the waves and swam away.

The Mystic team toasted to Lou-Seal’s release with the Gosling’s rum. Thanks to a satellite tracking device, they hope to follow her journey for about a year. “She is a unique case,” Callan says, “so we wanted to monitor her location and depth post-release.”

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How to Cure Groupthink

By Farah Mohammed

Social groups aim for harmony. It’s one of the primary objectives of every community—but there can always be too much of a good thing. When the social pressure to maintain harmony becomes greater than the individual’s dedication to the task the group is pursuing, that can ultimately cost the group dearly. It’s a not uncommon phenomenon sometimes referred to as “groupthink.”

In the Journal of Business Ethics, author Ronald Sims examines the extent of damage that groupthink can create, and more importantly, how to identify it and stem it in our own circles.

Political and Corporate Groupthink

Sims cites famous historical blunders attributed to the toxic effects of pressured group decision making, including Neville Chamberlain’s policy of appeasement of Hitler; President Truman’s advisors’ support of escalating war in North Korea, despite warnings from China about their inevitable strong reaction; President Kennedy’s inner circle’s support of the infamous Bay of Pigs invasion, despite its slim chance of success; and President Johnson’s advisors’ advocating the decision to head into Vietnam, despite intelligence reports advising that it was unlikely to defeat the Vietcong.

Sims quotes Irving Janis, who developed the theory of groupthink:

All these groupthink dominated groups were characterized by strong pressures toward uniformity, which inclined their members to avoid raising controversial issues, questioning weak arguments, or calling a halt to soft-headed thinking.

More mundane, but no less important, is the effect groupthink has on businesses and corporations every day. Especially in today’s world, where a few private businesses hold an inordinate amount of power, the ability of a few select groups of people to maintain a clear ethical direction has never been more important.

The Telltale Signs

We’d all like to believe that our groups and our communities are impervious to the effects of groupthink. What leads to a dangerous level of groupthink, however, isn’t an inherent weakness, or a collection of morally-lacking agents ready and waiting to conspire.

Rather, it’s the result of a tight-knit, insulated group with a strong leader, potentially in a stressful situation with little hope for finding a satisfactory solution other than the one presented to them, or the one favored by the group.

Symptoms of a group at risk of groupthink, according to Sims, are:

  • Illusion of invulnerability
  • Collective efforts to rationalize the group’s course of action
  • Unwillingness to reconsider assumptions
  • Unquestioned belief in the group’s inherent morality
  • Stereotyped view of those outside of the group
  • Suppression of dissent within the group

The Cure?

Sims offers steps for leaders, organizations, and individuals to combat letting groupthink settle into the psyches of their organizations.

Leaders can give everyone a role of critically evaluating a decision, and abstain from stating their own preferences, as well as bringing in outside experts to challenge the group. They can make “playing devil’s advocate” a standard part of decision-making procedure.

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Organizations can encourage healthy debate and discussion, and not shy away from dissent or view it as a negative part of company culture. They can encourage training in and engagement with ethics as much as with other practical skills. Periodically rotating new members in and old members out of groups may ease insulation or discourage the formation or overly rigid group dynamics.

Individually we can all contribute: critical thinking and following an internal moral compass on an individual level are the best starting points to maintaining a group’s integrity.

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The Amazing Eyes of the Archerfish

By James MacDonald

The archerfish inhabits shallow water across much of tropical Asia and Northern Australia. Unlike most fish, archerfish have a unique hunting method. Feeding on insects, these fish choose a target perched above the water, take aim, and then spit a jet of water at the hapless bug. If the shot strikes home, the insect falls into the water where the fish can easily capture it. These piscine water guns make it look easy, but it isn’t.

Scholar K. H. Lüling explains how such a feat is possible. After all, most fish cannot generate a spout of water. From the outside the archerfish’s mouth looks the same as any other fish’s mouth, but it has some subtle modifications. In particular, the tongue is flatter at the front and thicker towards the back of the mouth, and fits into a depression in the top of the mouth. With the tight fit, only a small funnel exists between the tongue and the top of the mouth. When it is time to shoot, the fish rapidly closes its gill covers, and water is forced through the narrow passage at high pressure. Some species can shoot seven to ten feet.

A bigger challenge for the fish, however, is accurate aim. As biologist Lawrence M. Dill explains, the archerfish keeps its eyes under the water’s surface when it stalks prey. When light hits water, it is refracted, distorting the appearance of an object above the surface to the fish observing below. That means the fish must hunt and aim without being able to see exactly where its prey is; the fish must compensate for refraction every time in order to hit its target. Below the surface, additional senses such as smell cannot help, so the process is entirely visual.

To avoid detection, the fish cannot approach from directly below the prey where refraction is minimized. The fish must instead approach from different angles, and the angle of refraction changes depending on the position of the fish relative to its prey. Refraction also distorts the apparent distance and elevation of the prey, creating further difficulties. Nor is the archerfish water jet immune to physics; the water droplet trajectory curves with distance travels, and the fish must compensate for that with its aim. Accuracy declines with the increasing shot distance, but despite the difficulties the archerfish frequently aims accurately.

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It is now known that the structure of the archerfish’s eye helps compensate for the distortion at the air/water interface. Still, their ability to compensate for all of the factors at once is one of the most impressive feats of marksmanship anywhere.

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Camouflage Gets Weird

By James MacDonald

Camouflage is one of the most incredible phenomena in the animal world. Animals can change color or even texture, blend into the background, and virtually disappear. Such camouflage is intended to fool predators who hunt their prey using vision. But what if a predator relies on other senses besides vision? There’s camouflage for that too.

Zoologist Graeme D. Ruxton writes about one quite common way of avoiding non-visual detection: staying silent. Keeping quiet is an easy way to avoid notice when predators are near. Ruxton, however, considers that technique to be hiding rather than camouflage. Of course, some organisms might not be able to stay silent. Some frogs, hiding from bats during mating season when silence is not an option, sometimes make simpler calls that attract less attention. They only ramp up complexity when many other frogs are around. This both offers safety in numbers and increases the potential payoff for the risk.

A much rarer technique is chemical crypsis, or altering scent to match background odors and avoid olfactory predators. Take the Biston robustum, the caterpillar of the giant geometer moth. These insects resemble twigs, but they also seem to match the chemical signature of their home twigs. Ants hunt through scent, and they will walk right over the caterpillars on their home twigs. Move one of these caterpillars to a different plant, however, and the ants quickly attack. Luckily, as soon as the caterpillars molt and feed on the new plant, they regain their chemical camouflage. Since the protection comes from their diet, they are safe as long as they stay on one type of plant.

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There are other unusual ways to use camouflage, and in fact some predators can use camouflage as well. Certain predatory fish will follow directly behind prey fish, hiding in the wake generated by their caudal fins. Hiding in the disturbed water of the wake can foil the sensitivity to water movements that most fishes have. In this manner the predator can remain undetected until it is too late for the prey.

Even more esoteric senses such as vibration detection and electrosensing have countermeasures. Of course there are no known examples of camouflage against heat sensors, such as the pits of pit vipers. But for the most part, if a means to detect prey or danger exists, defenses have probably evolved to foil it.

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Artificial Photosynthesis

By James MacDonald

When it comes to removing carbon dioxide from the atmosphere, nothing beats good old plants and their knack for photosynthesis. Photosynthesis is the process of converting sunlight, carbon dioxide, and water into oxygen and the sugars that feed all life on Earth. Ever since photosynthesis was discovered, scientists have been trying to artificially duplicate it. Now a French team thinks they have succeeded, at least on a small scale.

In a discussion of the potential avenues for artificial photosynthesis, science writer Katherine Bourzac notes that at its most basic, photosynthesis aims to convert energy and carbon into fuel. It’s really a form of solar power, sometimes called “wet solar,” for those situations when direct production of electricity is impractical. As Bourzac points out, at current levels of technology most of humanity uses liquid or gas fuel as energy. Until this changes, there need to be ways to produce carbon neutral, or near-neutral, fuels.

In both natural and artificial photosynthesis, water molecules are split into hydrogen and water. Plants absorb sunlight into pigments (e.g. chlorophyll), which energizes electrons; these juiced-up electrons are passed through a chain of molecules in a complicated process called electron transport. At the end of the process, the electrons split water.

Without electron transport, which nobody has yet been able to duplicate, splitting water can be a difficult and expensive process. (Unsurprisingly, interest in artificial photosynthesis research tends to rise and fall with oil prices.) The earliest attempts to simulate electron transport involved using sunlight to activate a circuit between platinum catalysts, or materials that facilitate a chemical reaction. Newer methods increase efficiency by running an electric current through the catalysts, developing better solar cells to directly feed energy into the system, and using cheaper metals as catalysts.

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If the goal is to produce hydrogen, which can be used as fuel, the process can stop there. However, there are cheaper ways to produce hydrogen, so the end goal is usually to keep going and create hydrocarbon fuels such as methane or butane, ideally using waste carbon from emissions. Plants make fuel for living things, so the desired result is conceptually similar. The trouble is that plants use complicated enzymes to create sugars from carbon, and the enzymes are damaged by the process. Plants easily repair their enzymes, but constructed materials are harder to fix. Several ongoing efforts have been trying to work around the problems by using solar electricity to split water and various bacteria to create the hydrocarbons. This approach is sometimes called a “living catalyst.”

The French researchers claim to have a fully artificial system, creating ethylene and ethane, both potent fuels, from the common mineral perovskite. The French system, as all the others, is still a prototype in a lab and a long way from being a functional way to produce sustainable fuel at scale—but it’s a promising start.

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Is Plastic Pollution Depriving Us of Oxygen?

By Lina Zeldovich

The plastic debris floating in the world’s oceans entangles wildlife, kills birds that swallow it mistaking it for food, and seeps into the food chain, showing up in fish that humans eat. A major threat to the ocean, this plastic pollution is estimated to cause more than $13 billion in economic damage to marine ecosystems each year. Turns out, it also disturbs important ocean bacteria, and the effects are far more profound than one may think.

Dispersed throughout the upper 200 meters of ocean, abundant and important bacteria known as Prochlorococcus govern many processes that happen not only inside that water, but also on land. These tiny green species have been called the ocean’s invisible forests because they perform similar functions to what plants do on earth. Prochlorococcus are photosynthetic organisms—they use sunlight to convert carbon dioxide into oxygen, adding it to the atmosphere like miniature plants. They are a type of Cyanobacteria, which were the planet’s first oxygen-producing creatures—so they are essentially the ancestors of today’s plants.

Prochlorococcus may be the most plentiful microorganisms on the planet. They produce nearly ten percent of the all the oxygen we breathe. A single drop of ocean water can contain 20,000 of them. But despite their abundance, they managed to evade modern science until fifteen years ago, when Sallie W. Chisholm from the Massachusetts Institute of Technology and Robert J. Olson from the Woods Hole Oceanographic Institution first discovered the species. Passing the ocean water through a flow cytometer—a device that detects and measures physical and chemical characteristics of particles suspended in fluids—the scientists noticed the cells, which were later named Prochlorococcus.

Prochlorococcus Dividing. Courtesy of Chisholm Lab.

Because there is less sunlight in the deep-sea water column, Prochlorococcus evolved to harvest light very efficiently. It is also a major player of the global carbon cycle. But scientists at the Macquarie University in Australia have found that these bacteria are susceptible to plastic pollution, which interferes with their growth, functioning, and oxygen production.

Working in lab settings, the team exposed two strains of Prochlorococcus, which live at different depths in the ocean, to chemicals leached from two common plastic products: polyvinyl chloride (PVC), and plastic grocery bags, which are made from high-density polyethylene.

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The scientists found that exposure to these chemicals impaired Prochlorococcus’s growth and function, including the amount of oxygen they produce. It also altered the bacteria’s expression in many of their genes. “We found that exposure to chemicals leaching from plastic pollution interfered with the growth, photosynthesis, and oxygen production of Prochlorococcus,” says Macquarie University researcher Sasha Tetu, lead author of the study published in Communications Biology. Moreover, the higher the concentration of the plastic pollution, the thinner the density of the bacterial population. The team’s next step would be to take their experiments out to sea and see how Prochlorococcus fare in nature. “Now we’d like to explore if plastic pollution is having the same impact on these microbes in the ocean,” Tetu says.

Is oxygen deprivation looming ahead? The diminished oxygen production will have a ripple effect through the earth’s ecosystems. “Plastic leachate exposure could influence marine Prochlorococcus community composition and potentially the broader composition and productivity of ocean phytoplankton communities,” the authors note in the study. We won’t start suffocating any time soon, but the magnitude of these changes isn’t yet understood.

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