Arquivo da tag: Controvérsias científicas

When Did the Anthropocene Start? Scientists Closer to Saying When. (N.Y. Times)

Uncategorized, , ,

nytimes.com

Image credits: Alamy; David Guttenfelder for The New York Times; Getty Images; Ashley Gilbertson for The New York Times; Michael Probst/Associated Press; Getty Images; NASA

A panel of experts has spent more than a decade deliberating on how, and whether, to mark a momentous new epoch in geologic time: our own.

Raymond Zhong

Dec. 17, 2022

The official timeline of Earth’s history — from the oldest rocks to the‌ dinosaurs to the rise of primates, from the Paleozoic to the Jurassic and all points before and since — could soon include the age of nuclear weapons, human-caused climate change and the proliferation of plastics, garbage and concrete across the planet.

In short, the present.

Ten thousand years after our species began forming primitive agrarian societies, a panel of scientists on Saturday took a big step toward declaring a new interval of geologic time: the Anthropocene, the age of humans.

Our current geologic epoch, the Holocene, began 11,700 years ago with the end of the last big ice age. The panel’s roughly three dozen scholars appear close to recommending that, actually, we have spent the past few decades in a brand-new time unit, one characterized by human-induced, planetary-scale changes that are unfinished but very much underway.

“If you were around in 1920, your attitude would have been, ‘Nature’s too big for humans to influence,’” said Colin N. Waters, a geologist and chair of the Anthropocene Working Group, the panel that has been deliberating on the issue since 2009. The past century has upended that thinking, Dr. Waters said. “It’s been a shock event, a bit like an asteroid hitting the planet.”

The working group’s members on Saturday completed the first in a series of internal votes on details including when exactly they believe the Anthropocene began. Once these votes are finished, which could be by spring, the panel will submit its final proposal to three other committees of geologists whose votes will either make the Anthropocene official or reject it.

Sixty percent of each committee will need to approve the group’s proposal for it to advance to the next. If it fails in any of them, the Anthropocene might not have another chance to be ratified for years.

If it makes it all the way, though, geology’s amended timeline would officially recognize that humankind’s effects on the planet had been so consequential as to bring the previous chapter of Earth’s history to a close. It would acknowledge that these effects will be discernible in the rocks for millenniums.

Source: Syvitski, et al. (2020)
By Mira Rojanasakul/The New York Times

“I teach the history of science — you know, Copernicus, Kepler, Galileo,” said Francine McCarthy, an earth scientist at Brock University in Canada and member of the working group. “We’re actually doing it,” she said. “We’re living the history of science.”

Still, the knives are out for the Anthropocene, even though, or maybe because, we all have such firsthand familiarity with it.

Stanley C. Finney, the secretary general of the International Union of Geological Sciences, fears the Anthropocene has become a way for geologists to make a “political statement.”

Within the vast expanse of geologic time, he notes, the Anthropocene would be a blip of a blip of a blip. Other geologic time units are useful because they orient scientists in stretches of deep time that left no written records and sparse scientific observations. The Anthropocene, by contrast, would be a time in Earth’s history that humans have already been documenting extensively.

“For the human transformation, we don’t need those terminologies — we have exact years,” said Dr. Finney, whose committee would be the last to vote on the working group’s proposal if it gets that far.

Martin J. Head, a working group member and earth scientist at Brock University, argues declining to recognize the Anthropocene would have political reverberations, too.

“People would say, ‘Well, does that then mean the geological community is denying that we have changed the planet drastically?’” he said. “We would have to justify our decision either way.”

Philip L. Gibbard, a geologist at the University of Cambridge, is secretary general of another of the committees that will vote on the working group’s proposal. He has serious concerns about how the proposal is shaping up, concerns he believes the wider geological community shares.

“It won’t get an easy ride,” he said.

A 19th century black-and-white print of five men in what appears to be a cave. One stands about knee-deep in a hole. The other four are examining a dinosaur skull.
Nineteenth-century fossil hunters. The rock record is full of gaps, “a jigsaw puzzle with many of the parts missing,” one geologist said. Credit: Oxford Science Archive/Print Collector, via Getty Images

Like the zoologists who regulate the names of animal species or the astronomers who decide what counts as a planet, geology’s timekeepers work conservatively, by design. They set classifications that will be reflected in academic studies, museums and textbooks for generations to come.

“Everybody picks on the Anthropocene Working Group because they’ve taken so long,” said Lucy E. Edwards, a retired scientist with the United States Geological Survey. “In geologic time, this isn’t long.”

The geologic time scale divides Earth’s 4.6 billion-year story into grandly named chapters. Like nesting dolls, the chapters contain sub-chapters, which themselves contain sub-sub-chapters. From largest to smallest, the chapters are called eons, eras, periods, epochs and ages.

Right now, according to the current timeline, we are in — deep breath — the Meghalayan Age of the Holocene Epoch of the Quaternary Period of the Cenozoic Era of the Phanerozoic Eon, and have been for 4,200 years.

Drawing lines in Earth time has never been easy. The rock record is full of gaps, “a jigsaw puzzle with many of the parts missing,” as Dr. Gibbard puts it. And most global-scale changes happen gradually, making it tricky to pinpoint when one chapter ended and the next one began. There haven’t been many moments when the entire planet changed at once.

“If a meteor hits the Yucatán Peninsula, that’s a pretty good marker,” Dr. Edwards said. “But other than that, there’s practically nothing out there in the geologic world that’s the best line.”

The early Cambrian Period, around 540 million years ago, saw Earth explode with an astonishing diversity of animal life, but its precise starting point has been contested for decades. A long controversy led to the redrawing of our current geologic period, the Quaternary, in 2009.

“It’s a messy and disputatious business,” said Jan A. Zalasiewicz, a geologist at the University of Leicester. “And of course, the Anthropocene brings a whole new range of dimensions to the messiness and disputatiousness.”

A nuclear test near the Marshall Islands in 1958. A working group proposed the mid-20th century as the beginning of the Anthropocene, in part because of the plutonium isotopes left by bombs. Credit: Corbis, via Getty Images

It took a decade of debate — in emails, academic articles and meetings in London, Berlin, Oslo and beyond — for the Anthropocene Working Group to nail down a key aspect of its proposal.

In a 29-to-4 vote in 2019, the group agreed to recommend that the Anthropocene began in the mid-20th century. That’s when human populations, economic activity and greenhouse gas emissions began skyrocketing worldwide, leaving indelible traces: plutonium isotopes from nuclear explosions, nitrogen from fertilizers, ash from power plants.

The Anthropocene, like nearly all other geologic time intervals, needs to be defined by a specific physical site, known as a “golden spike,” where the rock record clearly sets it off from the interval before it.

After a yearslong hunt, the working group on Saturday finished voting on nine candidate sites for the Anthropocene. They represent the range of environments into which human effects are etched: a peat bog in Poland, the ice of the Antarctic Peninsula, a bay in Japan, a coral reef off the Louisiana coast.

One site — Crawford Lake in Ontario, Canada — is small enough to walk around in 10 minutes. But it is so deep that the bottom layer of water rarely mixes with the upper layers. Whatever sinks to the floor remains undisturbed, gradually accumulating into a tree-ring-like record of geochemical change.

The working group’s members also voted this month on what rank the Anthropocene should have in the timeline: an epoch, an age of the Holocene, or something else.

The group isn’t disclosing the results of these or the other votes to be held in the coming months until they are all complete and it has finalized its proposal for the next level of timekeepers to ponder. It is then that a far more contentious debate about the Anthropocene could begin.

Many scholars still aren’t sure the mid-20th century cutoff makes sense. It is awkwardly recent, especially for archaeologists and anthropologists who would have to start referring to World War II artifacts as “pre-Anthropocene.”

Crawford Lake, near Milton, Ontario. Its depth makes it a prime site for scientific research. Credit: Conservation Halton

And using nuclear bombs to mark a geologic interval strikes some scientists as abhorrent, or at least beside the point. Radionuclides are a convenient global marker, but they say nothing about climate change or other human effects, said Erle C. Ellis, an ecologist at the University of Maryland, Baltimore County.

Using the Industrial Revolution might help. But that definition would still leave out millenniums of planet-warping changes from farming and deforestation.

Canonizing the Anthropocene is a call to attention, said Naomi Oreskes, a member of the working group. For geology, but also the wider world.

“I was raised in a generation where we were taught that geology ended when people showed up,” said Dr. Oreskes, a historian of science at Harvard. The Anthropocene announces that “actually, the human impact is part of geology as a science,” she said. It demands we recognize that our influence on the planet is more than surface level.

But Dr. Gibbard of Cambridge fears that, by trying to add the Anthropocene to the geologic time scale, the working group might actually be diminishing the concept’s significance. The timeline’s strict rules force the group to impose a single starting point on a sprawling story, one that has unspooled over different times in different places.

He and others argue the Anthropocene deserves a looser geologic label: an event. Events don’t appear on the timeline; no bureaucracy of scientists regulates them. But they have been transformative for the planet.

Late-Holocene human footprints, at least 2,000 years old, in volcanic ash and mud in Nicaragua. The Anthropocene could mark an official end to the 11,700-year-old Holocene Epoch. Credit: Carl Frank/Science Source

The filling of Earth’s skies with oxygen, roughly 2.1 to 2.4 billion years ago — geologists call that the Great Oxidation Event. Mass extinctions are events, as is the burst of diversity in marine life 460 to 485 million years ago.

The term Anthropocene is already in such wide use by researchers across scientific disciplines that geologists shouldn’t force it into too narrow a definition, said Emlyn Koster, a geologist and former director of the North Carolina Museum of Natural Sciences.

“I always saw it not as an internal geological undertaking,” he said of the Anthropocene panel’s work, “but rather one that could be greatly beneficial to the world at large.”

Raymond Zhong is a climate reporter. He joined The Times in 2017 and was part of the team that won the 2021 Pulitzer Prize in public service for coverage of the coronavirus pandemic. @zhonggg

A version of this article appears in print on Dec. 18, 2022, Section A, Page 1 of the New York edition with the headline: The Next Epoch Of Planet Earth Might Be Today. Order Reprints | Today’s Paper | Subscribe

Are we in the Anthropocene? Geologists could define new epoch for Earth (Nature)

Uncategorized, , , ,

Original article

Researchers have zeroed in on nine sites that could describe a new geological time, marked by pollution and other signs of human activity.

McKenzie Prillaman

13 December 2022

Geologists could soon decide which spot on Earth marks the first clear evidence of the Anthropocene — which many of them think is a new geological epoch that began when humans started altering the planet with various forms of industrial and radioactive materials in the 1950s. They have so far whittled their choices down to nine candidate sites worldwide (see ‘Defining the Anthropocene’), each being considered for how reliably its layers of mud, ice or other matter tell the story of people’s influence on a timeline that extends billions of years into the past.

If the nearly two dozen voting members of the Anthropocene Working Group (AWG), a committee of scientists formed by the International Commission on Stratigraphy (ICS), agree on a site, the decision could usher in the end of the roughly 12,000-year-old Holocene epoch. And it would officially acknowledge that humans have had a profound influence on Earth.

Geologists could soon decide which spot on Earth marks the first clear evidence of the Anthropocene — which many of them think is a new geological epoch that began when humans started altering the planet with various forms of industrial and radioactive materials in the 1950s. They have so far whittled their choices down to nine candidate sites worldwide (see ‘Defining the Anthropocene’), each being considered for how reliably its layers of mud, ice or other matter tell the story of people’s influence on a timeline that extends billions of years into the past.Humans versus Earth: the quest to define the Anthropocene

“We’re pointing to something in the rock record that shows we’ve changed the planet,” says Kristine DeLong, a palaeoclimatologist at Louisiana State University in Baton Rouge who studies the West Flower Garden Bank, a candidate site in the Gulf of Mexico.

The Anthropocene site will join 79 others that physically define stages of Earth’s geological timescale — that is, if it’s approved. Even if the AWG agrees on a final candidate, several other committees of geologists must vote on the selection before it is made official. And not all scientists agree that it should be.

Here, Nature examines what it will take to formally define the Anthropocene epoch.

Why do some geologists want an Anthropocene marker?

Scientists coined the term Anthropocene in 2000, and researchers from several fields now use it informally to refer to the current geological time interval, in which human activity is driving Earth’s conditions and processes. Formalizing the Anthropocene would unite efforts to study people’s influence on Earth’s systems, in fields including climatology and geology, researchers say. Transitioning to a new epoch might also coax policymakers to take into account the impact of humans on the environment during decision-making.

Coral growing on oil rig, Flower Garden Banks National Marine Sanctuary, Texas
Coral grows on an oil rig in Flower Garden Banks National Marine Sanctuary, in the Gulf of Mexico.Credit: Flip Nicklin/Minden Pictures/Alamy

“It’s a label,” says Colin Waters, who chairs the AWG and is a geologist at the University of Leicester, UK. “It’s a great way of summarizing a lot of concepts into one word.”

Mentioning the Jurassic period, for instance, helps scientists to picture plants and animals that were alive during that time, he says. “The Anthropocene represents an umbrella for all of these different changes that humans have made to the planet,” he adds.

How do scientists usually choose sites that define the geological timeline?

Typically, researchers will agree that a specific change in Earth’s geology must be captured in the official timeline. The ICS will then determine which set of rock layers, called strata, best illustrates that change, and it will choose which layer marks its lower boundary. This is called the Global Stratotype Section and Point (GSSP), and it is defined by a signal, such as the first appearance of a fossil species, trapped in the rock, mud or other material. One location is chosen to represent the boundary, and researchers mark this site physically with a golden spike, to commemorate it.

But the Anthropocene has posed problems. Geologists want to capture it in the timeline, but its beginning isn’t obvious in Earth’s strata, and signs of human activity have never before been part of the defining process. The AWG was established in 2009 to explore whether the Anthropocene should enter the geological timescale and, if so, how to define its start.

“We were starting from scratch,” says Jan Zalasiewicz, a geologist at the University of Leicester who formerly chaired the AWG and remains a voting member. “We had a vague idea about what it might be, [but] we didn’t know what kind of hard evidence would go into it.”

Years of debate among the group’s multidisciplinary members led them to identify a host of signals — radioactive isotopes from nuclear-bomb tests, ash from fossil-fuel combustion, microplastics, pesticides — that would be trapped in the strata of an Anthropocene-defining site. These began to appear in the early 1950s, when a booming human population started consuming materials and creating new ones faster than ever.

Cryogenian-Ediacaran geological boundary in rock strata marked by a brass plate, Flinders Ranges, South Australia
This golden spike in the Flinders Ranges of South Australia was approved by geologists in 2004, to mark strata exemplifying the Ediacaran period.Credit: James St. John (CC BY 2.0)

During a review that took place a few months ago, the AWG narrowed its list from 12 to 9 candidate sites, tossing out certain locations because their layers weren’t ideal. Among the sites remaining is Crawford Lake in Ontario, Canada, which is described as a sinkhole by Francine McCarthy, a geologist at Brock University in St Catharines, Canada, who studies the location. “The lake itself isn’t very big in area, but it’s very, very deep,” she says. Particles that fall into the lake settle at the bottom and accumulate into undisturbed layers.

Another site on the shortlist is West Flower Garden Bank. Corals here could become a living golden spike because they constantly build new exoskeletons that capture chemicals and particles from the water, DeLong says. “The skeleton has layers in it, kind of like tree rings,” she adds.

Why do some geologists oppose the Anthropocene as a new epoch?

“It misrepresents what we do” in the ICS, says Stanley Finney, a stratigrapher at California State University, Long Beach, and secretary-general for the International Union of Geological Sciences (IUGS). The AWG is working backwards, Finney says: normally, geologists identify strata that should enter the geological timescale before considering a golden spike; in this case, they’re seeking out the lower boundary of an undefined set of geological layers.Involve social scientists in defining the Anthropocene

Lucy Edwards, a palaeontologist who retired in 2008 from the Florence Bascom Geoscience Center in Reston, Virginia, agrees. For her, the strata that might define the Anthropocene do not yet exist because the proposed epoch is so young. “There is no geologic record of tomorrow,” she says.

Edwards, Finney and other researchers have instead proposed calling the Anthropocene a geological ‘event’, a flexible term that can stretch in time, depending on human impact. “It’s all-encompassing,” Edwards says.

Zalasiewicz disagrees. “The word ‘event’ has been used and stretched to mean all kinds of things,” he says. “So simply calling something an event doesn’t give it any wider meaning.”

What happens next?

In a recent Perspective article in Science, Waters and AWG secretary Simon Turner at University College London wrote that the committee would vote to choose a single site by the end of this year1. But 60% of the group’s voting members must agree on a final candidate — and, with several sites under consideration, Waters isn’t sure that a consensus can be reached anytime soon. If no clear winner emerges this month, more voting will be needed to narrow the candidate list, delaying a decision possibly until May 2023.Anthropocene now: influential panel votes to recognize Earth’s new epoch

And that’s not the end of the process. After selecting a finalist, the AWG will present its findings to the ICS’s Subcommission on Quaternary Stratigraphy. Favourable votes from this group would move the proposal to another ICS committee, and subsequent approval would push it to the final stage: ratification by the IUGS.

But the motion could fail at any of those points. And if it does, the AWG will have to revamp its proposal before it can try again — and possibly nominate a new golden-spike site.

Regardless of the outcome, Zalasiewicz thinks that the AWG’s work to define the Anthropocene has been useful. What everybody wants to know is how humans are changing the planet’s geology, he says. “That is the underlying reality that we’re trying to describe.”

The controversy about the relationship between GM mosquitoes and the Zika virus outbreak in Brazil

Uncategorized, , , , , ,

 

Pandora’s box: how GM mosquitos could have caused Brazil’s microcephaly disaster (The Ecologist)

Oliver Tickell

1st February 2016

Aedes Aegypti mosquito feeding on human blood. Photo: James Gathany via jentavery on Flickr (CC BY).

Aedes Aegypti mosquito feeding on human blood. This is the species that transmits Zika, and that was genetically engineered by Oxitec using the piggyBac transposon. Photo: James Gathany via jentavery on Flickr (CC BY).

In Brazil’s microcephaly epidemic, one vital question remains unanswered: how did the Zika virus suddenly learn how to disrupt the development of human embryos? The answer may lie in a sequence of ‘jumping DNA’ used to engineer the virus’s mosquito vector – and released into the wild four years ago in the precise area of Brazil where the microcephaly crisis is most acute.

These ‘promiscuous’ transposons have found special favour with genetic engineers, whose goal is to create ‘universal’ systems for transferring genes into any and every species on earth. Almost none of the geneticists has considered the hazards involved.

Since August 2015, a large number of babies in Northeast Brazil have been born with very small heads, a condition known as microcephaly, and with other serious malformations. 4,180 suspected cases have been reported.

Epidemiologists have found a convincing correlation between the incidence of the natal deformities and maternal infections with the Zika virus, first discovered in Uganda’s Zika Valley in 1947, which normally produces non-serious illness.

The correlation has been evidenced through the geographical distrubution of Zika infections and the wave of deformities. Zika virus has also been detected in the amniotic fluids and other tissues of the affected babies and their mothers.

This latter finding was recently reported by AS Oliveira Melo et al in a scientific paperpublished in the journal Ultrasound in Obstetrics & Gynecology, which noted evidence of intra-uterine infection. They also warn:

“As with other intrauterine infections, it is possible that the reported cases of microcephaly represent only the more severely affected children and that newborns with less severe disease, affecting not only the brain but also other organs, have not yet been diagnosed.”

The Brazilian Health Minister, Marcelo Castro, says he has “100% certainty” that there is a link between Zika and microcephaly. His view is supported by the medical community worldwide, including by the US Center for Disease Control.

Oliveira Melo et al draw attention to a mystery that lies at the heart of the affair: “It is difficult to explain why there have been no fetal cases of Zika virus infection reported until now but this may be due to the underreporting of cases, possible early acquisition of immunity in endemic areas or due to the rarity of the disease until now.

“As genomic changes in the virus have been reported, the possibility of a new, more virulent, strain needs to be considered. Until more cases are diagnosed and histopathological proof is obtained, the possibility of other etiologies cannot be ruled out.”

And this is the key question: how – if indeed Zika really is the problem, as appears likely – did this relatively innocuous virus acquire the ability to produce these terrible malformations in unborn human babies?

Oxitec’s GM mosquitoes

An excellent article by Claire Bernish published last week on AntiMedia draws attention to an interesting aspect of the matter which has escaped mainstream media attention: the correlation between the incidence of Zika and the area of release of genetically modified Aedes aegypti mosquitos engineered for male insterility (see maps, above right).

The purpose of the release was to see if it controlled population of the mosquitos, which are the vector of Dengue fever, a potentially lethal disease. The same species also transmits the Zika virus.

The releases took in 2011 and 2012 in the Itaberaba suburb of the city of Juazeiro, Bahia, Northeast Brazil, about 500 km west of ther coastal city of Recife. The experiment was written up in July 2015 in the journal PLOS Neglected Tropical Diseases in a paper titled ‘Suppression of a Field Population of Aedes aegypti in Brazil by Sustained Release of Transgenic Male Mosquitoes’ by Danilo O. Carvalho et al.

An initial ‘rangefinder of 30,000 GM mosquitos per week took place between 19th May and 29th June 2011, followed by a much larger release of 540,000 per week in early 2012, ending on 11th February.

At the end of it the scientists claimed “effective control of a wild population of Ae. aegypti by sustained releases of OX513A male Ae. aegypti. We diminished Ae. aegypti population by 95% (95% CI: 92.2%-97.5%) based on adult trap data and 78% (95% CI: 70.5%-84.8%) based on ovitrap indices compared to the adjacent no-release control area.”

So what’s to worry about?

    The idea of the Oxitec mosquitoes is simple enough: the males produce non-viable offspring which all die. So the GM mosqitoes are ‘self-extinguishing’ and the altered genes cannot survive in the wild population. All very clever, and nothing to worry about!

    But in fact, it’s not so simple. In 2010 geneticist Ricarda Steinbrecher wrote to the biosafety regulator in Malaysia – also considering a release of the Oxitec mosquitoes – with a number of safety concerns, pointing out the 2007 finding by Phuc et al that 3-4% of the first generation mosquitos actually survive.

    The genetic engineerig method employed by Oxitec allows the popular antibiotic tetracycline to be used to repress the lethality during breeding. But as a side-effect, the lethality is also reduced by the presence of tetracycline in the environment; and as Bernish points out, Brazil is among the world’s biggest users of anti-microbials including tetracycline in its commercial farming sector:

    “As a study by the American Society of Agronomy, et. al., explained, ‘It is estimated that approximately 75% of antibiotics are not absorbed by animals and are excreted in waste.’ One of the antibiotics (or antimicrobials) specifically named in that report for its environmental persistence is tetracycline.

    In fact, as a confidential internal Oxitec document divulged in 2012, that survival rate could be as high as 15% – even with low levels of tetracycline present. ‘Even small amounts of tetracycline can repress’ the engineered lethality. Indeed, that 15% survival rate was described by Oxitec.”

    She then quotes the leaked Oxitec paper: “After a lot of testing and comparing experimental design, it was found that [researchers] had used a cat food to feed the [OX513A] larvae and this cat food contained chicken. It is known that tetracycline is routinely used to prevent infections in chickens, especially in the cheap, mass produced, chicken used for animal food. The chicken is heat-treated before being used, but this does not remove all the tetracycline. This meant that a small amount of tetracycline was being added from the food to the larvae and repressing the [designed] lethal system.”

    So in other words, there is every possibility for Oxitec’s modified genes to persist in wild populations of Aedes aegypti mosquitos, especially in the environmental presence of tetracycline which is widely present in sewage, septic tanks, contaminated water sources and farm runoff.

    ‘Promiscuous’ jumping genes

    On the face of it, there is no obvious way in which the spread of Oxitec’s GM mosquitos into the wild could have anything to do with Brazil’s wave of micrcophaly. Is there?

    Actually, yes. The problem may arise from the use of the ‘transposon’ (‘jumping’ sequence of DNA used in the genetic engineering process to introduce the new genes into the target organism). There are several such DNA sequences in use, and one of the most popular is known as known as piggyBac.

    As a 2001 review article by Dr Mae Wan Ho shows, piggyBac is notoriously active, inserting itself into genes way beyond its intended target: “These ‘promiscuous’ transposons have found special favour with genetic engineers, whose goal is to create ‘universal’ systems for transferring genes into any and every species on earth. Almost none of the geneticists has considered the hazards involved …

    “It would seem obvious that integrated transposon vectors may easily jump out again, to another site in the same genome, or to the genome of unrelated species. There are already signs of that in the transposon, piggyBac, used in the GM bollworms to be released by the USDA this summer.

    The piggyBac transposon was discovered in cell cultures of the moth Trichopulsia, the cabbage looper, where it caused high rates of mutations in the baculovirus infecting the cells by jumping into its genes … This transposon was later found to be active in a wide range of species, including the fruitfly Drosophila, the mosquito transmitting yellow fever, Aedes aegypti, the medfly, Ceratitis capitata, and the original host, the cabbage looper.

    “The piggyBac vector gave high frequencies of transpositions, 37 times higher than mariner and nearly four times higher than Hirmar.”

    In a later 2014 report Dr Mae Wan Ho returned to the theme with additional detail and fresh scientific evidence (please refer to her original article for references): “The piggyBac transposon was discovered in cell cultures of the moth Trichopulsia, the cabbage looper, where it caused high rates of mutations in the baculovirus infecting the cells by jumping into its genes …

    “There is also evidence that the disabled piggyBac vector carrying the transgene, even when stripped down to the bare minimum of the border repeats, was nevertheless able to replicate and spread, because the transposase enzyme enabling the piggyBac inserts to move can be provided by transposons present in all genomes.

    “The main reason initially for using transposons as vectors in insect control was precisely because they can spread the transgenes rapidly by ‘non-Mendelian’ means within a population, i.e., by replicating copies and jumping into genomes, thereby ‘driving’ the trait through the insect population. However, the scientists involved neglected the fact that the transposons could also jump into the genomes of the mammalian hosts including human beings …

    “In spite of instability and resulting genotoxicity, the piggyBac transposon has been used extensively also in human gene therapy. Several human cell lines have been transformed, even primary human T cells using piggyBac. These findings leave us little doubt that the transposon-borne transgenes in the transgenic mosquito can transfer horizontally to human cells. The piggyBac transposon was found to induce genome wide insertionmutations disrupting many gene functions.” 

    Has the GM nightmare finally come true?

    So down to the key question: was the Oxitec’s GM Aedes aegypti male-sterile mosquito released in Juazeiro engineered with the piggyBac transposon? Yes, it was. And that creates a highly significant possibility: that Oxitec’s release of its GM mosquitos led directly to the development of Brazil’s microcephaly epidemic through the following mechanism:

    1. Many of the millions of Oxitec GM mosquitos released in Juazeiro in 2011/2012 survive, assisted, but not dependent on, the presence of tetracycline in the environment.

    2. These mosquitos interbreed with with the wild population and their novel genes become widespread.

    3. The promiscuous piggyBac transposon now present in the local Aedes aegyptipopulation takes the opportunity to jump into the Zika virus, probably on numerous occasions.

    4. In the process certain mutated strains of Zika acquire a selective advantage, making them more virulent and giving them an enhanced ability to enter and disrupt human DNA.

    5. One way in which this manifests is by disrupting a key stage in the development of human embryos in the womb, causing microcephaly and the other reported deformations. Note that as Melo Oliveira et al warn, there are almost certainly other manifestations that have not yet been detected.

    6. It may be that the piggyBac transposon has itself entered the DNA of babies exposed in utero to the modified Zika virus. Indeed, this may form part of the mechanism by which embryonic development is disrupted.

    In the latter case, one implication is that the action of the gene could be blocked by giving pregnant women tetracycline in order to block its activity. The chances of success are probably low, but it has to be worth trying.

    No further releases of GM insects!

    While I am certainly not claiming that this is what actually took place, it is at least a credible hypothesis, and moreover a highly testable one. Nothing would be easier for genetic engineers than to test amniotic fluids, babies’ blood, wild Aedes mosquitos and the Zika virus itself for the presence of the piggyBac transposon, using well established and highly sensitive PCR (polymerase chain reaction) techniques.

    If this proves to be the case, those urging caution on the release of GMOs generally, and transgenic insects bearing promiscuous transposons in particular, will have been proved right on all counts.

    But most important, such experiments, and any deployment of similar GM insects, must be immediately halted until the possibilities outlined above can be safely ruled out. There are plans, for example, to release similarly modified Anopheles mosquitos as an anti-malarial measure.

    There are also calls for even more of the Oxitec Aedes aegypti mosquitos to be released in order to halt the transmission of the Zika virus. If that were to take place, it could give rise to numerous new mutations of the virus with the potential to cause even more damage to the human genome, that we can, at this stage, only guess at.

    Oliver Tickell edits The Ecologist.

     

    No, GM Mosquitoes Didn’t Start The Zika Outbreak (Discovery)

    By Christie Wilcox | January 31, 2016 9:56 pm

    ZIka_conspiracy_theory_cat

    A new ridiculous rumor is spreading around the internets. According to conspiracy theorists, the recent outbreak of Zika can be blamed on the British biotech company Oxitec, which some are saying even intentionally caused the disease as a form of ethnic cleansing or population control. The articles all cite a lone Redditor who proposed the connection on January 25th to the Conspiracy subreddit. “There are no biological free lunches,” says one commenter on the idea. “Releasing genetically altered species into the environment could have disastrous consequences” another added. “Maybe that’s what some entities want to happen…?”

    For some reason, it’s been one of those months where random nonsense suddenly hits mainstream. Here are the facts: there’s no evidence whatsoever to support this conspiracy theory, or any of the other bizarre, anti-science claims that have popped up in the past few weeks. So let’s stop all of this right here, right now: The Earth is round, not flat (and it’s definitely not hollow). Last year was the hottest year on record, and climate change is really happening (so please just stop, Mr. Cruz). And FFS, genetically modified mosquitoes didn’t start the Zika outbreak. 

    Background on Zika

    The Zika virus is a flavivirus closely related to notorious pathogens including dengue, yellow fever, Japanese encephalitis, and West Nile virus. The virus is transmitted by mosquitoes in the genus Aedes, especially A. aegypti, which is a known vector for many of Zika’s relatives. Symptoms of the infection appear three to twelve days post bite. Most people are asymptomatic, which means they show no signs of infection. The vast majority of those who do show signs of infection report fever, rash, joint pain, and conjunctivitis (red eyes), according to the U.S. Centers for Disease Control. After a week or less, the symptoms tend to go away on their own. Serious complications have occurred, but they have been extremely rare.

    The Zika virus isn’t new. It was first isolated in 1947 from a Rhesus monkey in the Zika Forest in Uganda, hence the pathogen’s name. The first human cases were confirmed in Uganda and Tanzania in 1952, and by 1968, the virus had spread to Nigeria. But since then, the virus has found its way out of Africa. The first major outbreak occurred on the island of Yap in Micronesia for 13 weeks 2007, during which 185 Zika cases were suspected (49 of those were confirmed, with another 59 considered probable). Then, in October 2013, an outbreak began in French Polynesia; around 10,000 cases were reported, less than 100 of which presented with severe neurological or autoimmune complications. One confirmed case of autochthonous transmission occurred in Chile in 2014, which means a person was infected while they were in Chile rather than somewhere else. Cases were also reported that year from several Pacific Islands. The virus was detected in Chile until June 2014, but then it seemed to disappear.

    Fast forward to May 2015, when the Pan American Health Organization (PAHO) issued an alert regarding the first confirmed Zika virus infection in Brazil. Since then, several thousand suspected cases of the disease and a previously unknown complication—a kind of birth defect known as microcephaly where the baby’s brain is abnormally small—have been reported from Brazil. (It’s important to note that while the connection between the virus and microcephaly is strongly suspected, the link has yet to be conclusively demonstrated.)

    Currently, there is no vaccine for Zika, though the recent rise in cases has spurred research efforts. Thus, preventing mosquito bites is the only prophylactic measure available.

    The recent spread of the virus has been described as “explosive”; Zika has now been detected in 25 countries and territories. The rising concern over both the number of cases and reports of serious complications has led the most affected areas in Brazil to declare a state of emergency, and on Monday, The World Health Organization’s Director-General will convene an International Health Regulations Emergency Committee on Zika virus and the observed increase in neurological disorders and neonatal malformations. At this emergency meeting, the committee will discuss mitigation strategies and decide whether the organization will officially declare the virus a “Public Health Emergency of International Concern.”

    GM to the Rescue

    aedes_aegypti

    The mosquito to blame for the outbreak—Aedes aegypti—doesn’t belong in the Americas. It’s native to Africa, and was only introduced in the new world when Europeans began to explore the globe. In the 20th century, mosquito control programs nearly eradicated the unwelcome menace from the Americas (largely thanks to the use of the controversial pesticide DDT); as late as the mid 1970s, Brazil and 15 other nations were Aedes aegypti-free. But despite the successes, eradication efforts were halted, allowing the mosquito to regain its lost territory.

    The distribution of Aedes aegypti in the Americas in 1970 and 2002.

    Effective control measures are expensive and difficult to maintain, so at the tail end of the 20th century and into the 21st, scientists began to explore creative means of controlling mosquito populations, including the use of genetic modification. Oxitec’s mosquitoes are one of the most exciting technologies to have emerged from this period. Here’s how they work, as I described in a post almost exactly a year ago:

    While these mosquitoes are genetically modified, they aren’t “cross-bred with the herpes simplex virus and E. colibacteria” (that would be an interkingdom ménage à trois!)—and no, they cannot be “used to bite people and essentially make them immune to dengue fever and chikungunya” (they aren’t carrying a vaccine!). The mosquitoes that Oxitec have designed are what scientists call “autocidal” or possess a “dominant lethal genetic system,” which is mostly fancy wording for “they die all by themselves”. The males carry inserted DNA which causes the mosquitoes to depend upon a dietary supplement that is easy to provide in the lab, but not available in nature. When the so-called mutants breed with normal females, all of the offspring require the missing dietary supplement because the suicide genes passed on from the males are genetically dominant. Thus, the offspring die before they can become adults. The idea is, if you release enough such males in an area, then the females won’t have a choice but to mate with them. That will mean there will be few to no successful offspring in the next generation, and the population is effectively controlled.

    Male mosquitoes don’t bite people, so they cannot serve as transmission vectors for Zika or any other disease. As for fears that GM females will take over: less than 5% of all offspring survive in the laboratory, and as Glen Slade, director of Oxitec’s Brazilian branch notes, those are the best possible conditions for survival. “It is considered unlikely that the survival rate is anywhere near that high in the harsher field conditions since offspring reaching adulthood will have been weakened by the self-limiting gene,” he told me. And contrary to what the conspiracy theorists claim, scientists have shown that tetracycline in the environment doesn’t increase that survival rate.

    Brazil, a hotspot for dengue and other such diseases, is one of the countries where Oxitec is testing their mozzies—so far, everywhere that Oxitec’s mosquitoes have been released, the local populations have been suppressed by about 90%.

    Wrong Place, Wrong Time

    Now that we’ve covered the background on the situation, let’s dig into the conspiracy theory. We’ll start with the main argument laid out as evidence: that the Zika outbreak began in the same location at the same time as the first Oxitec release:

    Though it’s often said, it’s worth repeating: correlation doesn’t equal causation. If it did, then Nicholas Cage is to blame for people drowning (Why, Nick? WHY?). But even beyond that, there are bigger problems with this supposed correlation: even by those maps, the site of release is on the fringe of the Zika hotspot, not the center of it. Just look at the two overlaid:

    The epicenter of the outbreak and the release clearly don’t line up—the epicenter is on the coast rather than inland where the map points. Furthermore, the first confirmed cases weren’t reported in that area, but in the town of Camaçari, Bahia, which is—unsurprisingly—on the coast and several hundred kilometers from the release site indicated.

    But perhaps more importantly, the location on the map isn’t where the mosquitoes were released. That map points to Juazeiro de Norte, Ceará, which is a solid 300 km away from Juazeiro, Bahia—the actual site of the mosquito trial. That location is even more on the edge of the Zika-affected area:

    1: Juaziero de Norte, the identified location in by conspiracy theorists. 2: Juaziero, the actual location of Oxitec's release trial, about 300 km away.

    The mistake was made initially by the Redditor who proposed the conspiracy theory and has been propagated through lazy journalistic practices by every proponent since. Here’s a quick tip: if you’re basing your conspiracy theory on location coincidence, it’s probably a good idea to actually get the location right.

    They’re also wrong about the date. According to the D.C. Clothesline:

    By July 2015, shortly after the GM mosquitoes were first released into the wild in Juazeiro, Brazil, Oxitec proudly announced they had “successfully controlled the Aedes aegypti mosquito that spreads dengue fever, chikungunya and zika virus, by reducing the target population by more than 90%.”

    However, GM mosquitoes weren’t first released in Juazeiro, Bahia (let alone Juazeiro de Norte, Ceará) in 2015. Instead, the announcement by Oxitec was of the published results of a trial that occurred in Juaziero between May 2011 and Sept 2012—a fact which is clearly stated in the methods and results of the paper that Oxitec was so excited to share.

    A new control effort employing Oxitec mosquitoes did begin in April 2015, but not in Juaziero, or any of the northeastern states of Brazil where the disease outbreak is occurring. As another press release from Oxitec states, the 2015 releases of their GM mosquitoes were in Piracicaba, São Paulo, Brazil:

    Following approval by Brazil’s National Biosafety Committee (CTNBio) for releases throughout the country, Piracicaba’s CECAP/Eldorado district became the world’s first municipality to partner directly with Oxitec and in April 2015 started releasing its self-limiting mosquitoes whose offspring do not survive. By the end of the calendar year, results had already indicated a reduction in wild mosquito larvae by 82%. Oxitec’s efficacy trials across Brazil, Panama and the Cayman Islands all resulted in a greater than 90% suppression of the wild Ae. aegypti mosquito population–an unprecedented level of control.

    Based on the positive results achieved to date, the ‘Friendly Aedes aegypti Project’ in CECAP/Eldorado district covering 5,000 people has been extended for another year. Additionally, Oxitec and Piracicaba have signed a letter of intent to expand the project to an area of 35,000-60,000 residents. This geographic region includes the city’s center and was chosen due to the large flow of people commuting between it and surrounding neighborhoods which may contribute to the spread of infestations and infections.

    Piracicaba mosquito control results

     

    Piracicaba, for the record, is more than 1300 miles away from the Zika epicenter:

    TKTK

    So not only did the conspiracy theorists get the location of the first Brazil release wrong, they either got the date wrong, too, or got the location of the 2015 releases really, really off. Either way, the central argument that the release of GM mosquitoes by Oxitec coincides with the first cases of Zika virus simply doesn’t hold up.

    Scientists Speak Out

    As this ludicrous conspiracy theory has spread, so, too, has the scientific opposition to it. “Frankly, I’m a little sick of this kind of anti-science platform,” said vector ecologist Tanjim Hossain from the University of Miami, when I asked him what he thought. “This kind of fear mongering is not only irresponsible, but may very well be downright harmful to vulnerable populations from a global health perspective.”

    Despite the specious allusions made by proponents of the conspiracy, this is still not Jurassic Park, says Hossain.

    “We have a problem where ZIKV is spreading rapidly and is widely suspected of causing serious health issues,” he continued. “How do we solve this problem? An Integrated Vector Management (IVM) approach is key. We need to use all available tools, old and new, to combat the problem. GM mosquitoes are a fairly new tool in our arsenal. The way I see it, they have the potential to quickly reduce a local population of vector mosquitoes to near zero, and thereby can also reduce the risk of disease transmission. This kind of strategy could be particularly useful in a disease outbreak ‘hotspot’ because you could hypothetically stop the disease in its tracks so to speak.”

    Other scientists have shared similar sentiments. Alex Perkins, a biological science professor at Notre Dame, told Business Insider that rather than causing the outbreak, GM mosquitoes might be our best chance to fight it. “It could very well be the case that genetically modified mosquitos could end up being one of the most important tools that we have to combat Zika,” Perkins said. “If anything, we should potentially be looking into using these more.”

    Brazilian authorities couldn’t be happier with the results so far, and are eager to continue to fight these deadly mosquitoes by any means they can. “The initial project in CECAP/Eldorado district clearly showed that the ‘friendly Aedes aegypti solution’ made a big difference for the inhabitants of the area, helping to protect them from the mosquito that transmits dengue, Zika and chikungunya,” said Pedro Mello, secretary of health in Piracicaba. He notes that during the 2014/2015 dengue season, before the trial there began, there were 133 cases of dengue. “In 2015/2016, after the beginning of the Friendly Aedes aegypti Project, we had only one case.”

    It’s long past time to stop villainizing Oxitec’s mosquitoes for crimes they didn’t commit. Claire Bernish, The Daily MFail, Mirror and everyone else who has spread these baseless accusations: I’m talking to you. The original post was in the Conspiracy subreddit—what more of a red flag for “this is wildly inaccurate bullsh*t” do you need? (After all, if this is a legit source, where are your reports on the new hidden messages in the $100 bill? or why the Illuminati wants people to believe in aliens?). It’s well known that large-scale conspiracy theories are mathematically challenged. Don’t just post whatever crap is spewed on the internet because you know it’ll get you a few clicks. It’s dishonest, dangerous, and, frankly, deplorable to treat nonsense as possible truth just to prey upon your audience’s very real fears of an emerging disease. You, with your complete lack of integrity, are maggots feeding on the decay of modern journalism, and I mean that with no disrespect to maggots.