Tuesday, 27 October 2015
Don't Be Fooled -The Greys Are Still Out To Get You...
Sunday, 25 October 2015
Memories Are Made Of These....even bad ones!!
Oh, how the years fly! I was going through the Hooper Report: Final Report of Project Grey Book, which has been edited to the extent that it can be published as an historical document looking at the AOP Bureau work and solution to UFOs.
Yes, if I ever get round to typing the near 500+ pages (cut down from 1,900+ pages) people will see what Ufologists in this country were offered a view of back in 1983 (three years after the Report was written) but flatly refused to even see a copy of -and I do still have the written responses from BUFORA and "leading Ufologists"!
But I came across a forgotten photograph in the Report. It is one of a young, bearded man standing near to one of RAF Manston's radar units in 1979 at a time of high activity.
Sadly, the "AOP B" badge on the left sleeve cannot really be seen -no digital photos in those days.
Ahhh. To still have that hair!
Yes, if I ever get round to typing the near 500+ pages (cut down from 1,900+ pages) people will see what Ufologists in this country were offered a view of back in 1983 (three years after the Report was written) but flatly refused to even see a copy of -and I do still have the written responses from BUFORA and "leading Ufologists"!
But I came across a forgotten photograph in the Report. It is one of a young, bearded man standing near to one of RAF Manston's radar units in 1979 at a time of high activity.
Sadly, the "AOP B" badge on the left sleeve cannot really be seen -no digital photos in those days.
Ahhh. To still have that hair!
Just How Old IS The Plague??
Like I keep writing and saying, "We" keep finding out more and more and correcting text books and re-writing history and that is what true science is about.
According to Cambridge University Research page: http://www.cam.ac.uk/research/news/plague-in-humans-twice-as-old-but-didnt-begin-as-flea-borne-ancient-dna-reveals
According to Cambridge University Research page: http://www.cam.ac.uk/research/news/plague-in-humans-twice-as-old-but-didnt-begin-as-flea-borne-ancient-dna-reveals
Plague in humans ‘twice as old’ but didn’t begin as flea-borne, ancient DNA reveals
New
research dates plague back to the early Bronze Age, showing it had been
endemic in humans across Eurasia for millennia prior to first recorded
global outbreak, and that ancestral plague mutated into its bubonic,
flea-borne form between the 2nd and 1st millennium BC.
New
research dates plague back to the early Bronze Age, showing it had been
endemic in humans across Eurasia for millennia prior to first recorded
global outbreak, and that ancestral plague mutated into its bubonic,
flea-borne form between the 2nd and 1st millennium BC.
These results show that the ancient DNA has the potential not only to map our history and prehistory, but also discover how disease may have shaped itEske Willerslev
New
research using ancient DNA has revealed that plague has been endemic in
human populations for more than twice as long as previously thought,
and that the ancestral plague would have been predominantly spread by
human-to-human contact – until genetic mutations allowed Yersinia pestis (Y. pestis), the bacteria that causes plague, to survive in the gut of fleas.
These mutations, which may have occurred near the turn of the 1st millennium BC, gave rise to the bubonic form of plague that spreads at terrifying speed through flea – and consequently rat – carriers. The bubonic plague caused the pandemics that decimated global populations, including the Black Death, which wiped out half the population of Europe in the 14th century.
Before its flea-borne evolution, however, researchers say that plague was in fact endemic in the human populations of Eurasia at least 3,000 years before the first plague pandemic in historical records (the Plague of Justinian in 541 AD).
They say the new evidence that Y. pestis bacterial infection in humans actually emerged around the beginning of the Bronze Age suggests that plague may have been responsible for major population declines believed to have occurred in the late 4th and early 3rd millennium BC.
The work was conducted by an international team including researchers from the universities of Copenhagen, Denmark, and Cambridge, UK, and the findings are published today in the journal Cell.
“We found that the Y. pestis lineage originated and was widespread much earlier than previously thought, and we narrowed the time window as to when and how it developed,” said senior author Professor Eske Willerslev, who recently joined Cambridge University’s Department of Zoology from the University of Copenhagen.
“The underlying mechanisms that facilitated the evolution of Y. pestis are present even today. Learning from the past may help us understand how future pathogens may arise and evolve,” he said.
Researchers analysed ancient genomes extracted from the teeth of 101 adults dating from the Bronze Age and found across the Eurasian landmass.
They found Y. pestis bacteria in the DNA of seven of the adults, the oldest of whom died 5,783 years ago – the earliest evidence of plague. Previously, direct molecular evidence for Y. pestis had not been obtained from skeletal material older than 1,500 years.
However, six of the seven plague samples were missing two key genetic components found in most modern strains of plague: a “virulence gene” called ymt, and a mutation in an “activator gene” called pla.
The ymt gene protects the bacteria from being destroyed by the toxins in flea guts, so that it multiplies, choking the flea’s digestive tract. This causes the starving flea to frantically bite anything it can, and, in doing so, spread the plague.
The mutation in the pla gene allows Y. pestis bacteria to spread across different tissues, turning the localised lung infection of pneumonic plague into one of the blood and lymph nodes.
Researchers concluded these early strains of plague could not have been carried by fleas without ymt. Nor could they cause bubonic plague – which affects the lymphatic immune system, and inflicts the infamous swollen buboes of the Black Death – without the pla mutation.
Consequently, the plague that stalked populations for much of the Bronze Age must have been pneumonic, which directly affects the respiratory system and causes desperate, hacking coughing fits just before death. Breathing around infected people leads to inhalation of the bacteria, the crux of its human-to-human transmission.
Study co-author Dr Marta Mirazón-Lahr, from Cambridge’s Leverhulme Centre for Human Evolutionary Studies (LCHES), points out that a study earlier this year from Willerslev’s Copenhagen group showed the Bronze Age to be a highly active migratory period, which could have led to the spread of pneumonic plague.
“The Bronze Age was a period of major metal weapon production, and it is thought increased warfare, which is compatible with emerging evidence of large population movements at the time. If pneumonic plague was carried as part of these migrations, it would have had devastating effects on small groups they encountered,” she said.
“Well-documented cases have shown the pneumonic plague’s chain of infection can go from a single hunter or herder to ravaging an entire community in two to three days.”
The most recent of the seven ancient genomes to reveal Y. pestis in the new study has both of the key genetic mutations, indicating an approximate timeline for the evolution that spawned flea-borne bubonic plague.
“Among our samples, the mutated plague strain is first observed in Armenia in 951 BC, yet is absent in the next most recent sample from 1686 BC – suggesting bubonic strains evolve and become fixed in the late 2nd and very early 1st millennium BC,” said Mirazón-Lahr.
“However, the 1686 BC sample is from the Altai mountains near Mongolia. Given the distance between Armenia and Altai, it’s also possible that the Armenian strain of bubonic plague has a longer history in the Middle East, and that historical movements during the 1st millennium BC exported it elsewhere.”
The Books of Samuel in the Bible describe an outbreak of plague among the Philistines in 1320 BC, complete with swellings in the groin, which the World Health Organization has argued fits the description of bubonic plague. Mirazón-Lahr suggests this may support the idea of a Middle Eastern origin for the plague’s highly lethal genetic evolution.
Co-author Professor Robert Foley, also from Cambridge’s LCHES, suggests that the lethality of bubonic plague may have required the right population demography before it could thrive.
“Every pathogen has a balance to maintain. If it kills a host before it can spread, it too reaches a ‘dead end’. Highly lethal diseases require certain demographic intensity to sustain them.
“The endemic nature of pneumonic plague was perhaps more adapted for an earlier Bronze Age population. Then, as Eurasian societies grew in complexity and trading routes continued to open up, maybe the conditions started to favour the more lethal form of plague,” Foley said.
“The Bronze Age is the edge of history, and ancient DNA is making what happened at this critical time more visible,” he said.
Willerslev added: “These results show that the ancient DNA has the potential not only to map our history and prehistory, but also discover how disease may have shaped it.”
These mutations, which may have occurred near the turn of the 1st millennium BC, gave rise to the bubonic form of plague that spreads at terrifying speed through flea – and consequently rat – carriers. The bubonic plague caused the pandemics that decimated global populations, including the Black Death, which wiped out half the population of Europe in the 14th century.
Before its flea-borne evolution, however, researchers say that plague was in fact endemic in the human populations of Eurasia at least 3,000 years before the first plague pandemic in historical records (the Plague of Justinian in 541 AD).
They say the new evidence that Y. pestis bacterial infection in humans actually emerged around the beginning of the Bronze Age suggests that plague may have been responsible for major population declines believed to have occurred in the late 4th and early 3rd millennium BC.
The work was conducted by an international team including researchers from the universities of Copenhagen, Denmark, and Cambridge, UK, and the findings are published today in the journal Cell.
“We found that the Y. pestis lineage originated and was widespread much earlier than previously thought, and we narrowed the time window as to when and how it developed,” said senior author Professor Eske Willerslev, who recently joined Cambridge University’s Department of Zoology from the University of Copenhagen.
“The underlying mechanisms that facilitated the evolution of Y. pestis are present even today. Learning from the past may help us understand how future pathogens may arise and evolve,” he said.
Researchers analysed ancient genomes extracted from the teeth of 101 adults dating from the Bronze Age and found across the Eurasian landmass.
They found Y. pestis bacteria in the DNA of seven of the adults, the oldest of whom died 5,783 years ago – the earliest evidence of plague. Previously, direct molecular evidence for Y. pestis had not been obtained from skeletal material older than 1,500 years.
However, six of the seven plague samples were missing two key genetic components found in most modern strains of plague: a “virulence gene” called ymt, and a mutation in an “activator gene” called pla.
The ymt gene protects the bacteria from being destroyed by the toxins in flea guts, so that it multiplies, choking the flea’s digestive tract. This causes the starving flea to frantically bite anything it can, and, in doing so, spread the plague.
The mutation in the pla gene allows Y. pestis bacteria to spread across different tissues, turning the localised lung infection of pneumonic plague into one of the blood and lymph nodes.
Researchers concluded these early strains of plague could not have been carried by fleas without ymt. Nor could they cause bubonic plague – which affects the lymphatic immune system, and inflicts the infamous swollen buboes of the Black Death – without the pla mutation.
Consequently, the plague that stalked populations for much of the Bronze Age must have been pneumonic, which directly affects the respiratory system and causes desperate, hacking coughing fits just before death. Breathing around infected people leads to inhalation of the bacteria, the crux of its human-to-human transmission.
Study co-author Dr Marta Mirazón-Lahr, from Cambridge’s Leverhulme Centre for Human Evolutionary Studies (LCHES), points out that a study earlier this year from Willerslev’s Copenhagen group showed the Bronze Age to be a highly active migratory period, which could have led to the spread of pneumonic plague.
“The Bronze Age was a period of major metal weapon production, and it is thought increased warfare, which is compatible with emerging evidence of large population movements at the time. If pneumonic plague was carried as part of these migrations, it would have had devastating effects on small groups they encountered,” she said.
“Well-documented cases have shown the pneumonic plague’s chain of infection can go from a single hunter or herder to ravaging an entire community in two to three days.”
The most recent of the seven ancient genomes to reveal Y. pestis in the new study has both of the key genetic mutations, indicating an approximate timeline for the evolution that spawned flea-borne bubonic plague.
“Among our samples, the mutated plague strain is first observed in Armenia in 951 BC, yet is absent in the next most recent sample from 1686 BC – suggesting bubonic strains evolve and become fixed in the late 2nd and very early 1st millennium BC,” said Mirazón-Lahr.
“However, the 1686 BC sample is from the Altai mountains near Mongolia. Given the distance between Armenia and Altai, it’s also possible that the Armenian strain of bubonic plague has a longer history in the Middle East, and that historical movements during the 1st millennium BC exported it elsewhere.”
The Books of Samuel in the Bible describe an outbreak of plague among the Philistines in 1320 BC, complete with swellings in the groin, which the World Health Organization has argued fits the description of bubonic plague. Mirazón-Lahr suggests this may support the idea of a Middle Eastern origin for the plague’s highly lethal genetic evolution.
Co-author Professor Robert Foley, also from Cambridge’s LCHES, suggests that the lethality of bubonic plague may have required the right population demography before it could thrive.
“Every pathogen has a balance to maintain. If it kills a host before it can spread, it too reaches a ‘dead end’. Highly lethal diseases require certain demographic intensity to sustain them.
“The endemic nature of pneumonic plague was perhaps more adapted for an earlier Bronze Age population. Then, as Eurasian societies grew in complexity and trading routes continued to open up, maybe the conditions started to favour the more lethal form of plague,” Foley said.
“The Bronze Age is the edge of history, and ancient DNA is making what happened at this critical time more visible,” he said.
Willerslev added: “These results show that the ancient DNA has the potential not only to map our history and prehistory, but also discover how disease may have shaped it.”
Inset image: Map showing where the remains of the Bronze Age plague victims were found.
Friday, 23 October 2015
Possible Book Cancellations
The reasons are simple. I have two hefty books -Some Things Strange & Sinister and Some More Things Strange & Sinister as well as Pursuing The Strange And Weird -A Naturalist's Viewpoint and The Bizarre Legends, Crimes And Truth About Spring Heeled Jack (2014). To which you might add (since it has elements of "Cryptozoology") The Red Paper: Canids (over 40 years research work crammed into one handy book!).
The sales have been un-spectacular to say the least -one or two copies of the first three books. Review copies requested were never reviewed and promoting like crazy -including cutting the cover prices drastically- achieved nothing. Book stores are not interested in Independent books.
And I do need to eat and pay bills like everyone else. I look at a few of the "phenomena" books out there and they are not that good. Repetitive pot-boilers with not much original in them -certainly photo and image wise nothing new. It sounds like sickening egotism to say it but there is far more in one of my books and that really disappoints me because I had hoped that by now the sensationalistic approach ("I looked behind me and NOTHING was there. On that day I knew true evil existed!") would be "old school" with more factual reporting because only after thorough research and investigation can you find the cases that defy current explanation.
I will not turn a book into something sensationalistic to sell because the material in the books is sensationalistic enough -UFOs, ghosts, poltergeists, unknown sea creatures, Sasquatch and so on. I simply cannot produce a book of over sensationalistic lies to feed minds that will accept that every TV paranormal programme (introduced with "Intended for entertainment purposes only") does not contain trickery and lies.
I have the material but you are looking at a book taking a year to write/edit (SMTS&S like STS&S each 
had over 350 pages with illustrations, maps, photographs -many thought to have been lost forever). Look at the cover from the second book and an infamously 'lost' or even "non-existant" photo (you'll need to buy the book to answer the question "What?"
had over 350 pages with illustrations, maps, photographs -many thought to have been lost forever). Look at the cover from the second book and an infamously 'lost' or even "non-existant" photo (you'll need to buy the book to answer the question "What?"
Perhaps, one day I may be lucky to assemble a small team of investigators in Bristol to look into the strange and weird but I'm on week two of a mammoth read -so far three "Ghost" books and, I think now, five books on alien abductions/UFOs and Sasquatch and a stack of books is on the floor next to me!
TV -I'm still working on that but so far no serious offers or responses and, please, believe me, I do need to eat!
So if you are an Independent TV programme maker (and I do NOT do this for free!) get in touch.
Now, off to read!
The books are detailed here:
The books are detailed here:
Thursday, 22 October 2015
NASA’s K2 Finds Dead Star Vaporizing a Mini “Planet”
Scientists using NASA’s repurposed Kepler space telescope,
known as the K2 mission, have uncovered strong evidence of a tiny, rocky
object being torn apart as it spirals around a white dwarf star. This
discovery validates a long-held theory that white dwarfs are capable of
cannibalizing possible remnant planets that have survived within its
solar system.
“We are for the first time witnessing a miniature “planet” ripped apart by intense gravity, being vaporized by starlight and raining rocky material onto its star,” said Andrew Vanderburg, graduate student from the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, and lead author of the paper published in Nature.
As stars like our sun age, they puff up into red giants and then gradually lose about half their mass, shrinking down to 1/100th of their original size to roughly the size of Earth. This dead, dense star remnant is called a white dwarf.
The devastated planetesimal, or cosmic object formed from dust, rock, and other materials, is estimated to be the size of a large asteroid, and is the first planetary object to be confirmed transiting a white dwarf. It orbits its white dwarf, WD 1145+017, once every 4.5 hours. This orbital period places it extremely close to the white dwarf and its searing heat and shearing gravitational force.
During its first observing campaign from May 30, 2014 to Aug. 21, 2014, K2 trained its gaze on a patch of sky in the constellation Virgo, measuring the minuscule change in brightness of the distant white dwarf. When an object transits or passes in front of a star from the vantage point of the space telescope, a dip in starlight is recorded. The periodic dimming of starlight indicates the presence of an object in orbit about the star.
A research team led by Vanderburg found an unusual, but vaguely
familiar pattern in the data. While there was a prominent dip in
brightness occurring every 4.5 hours, blocking up to 40 percent of the
white dwarf's light, the transit signal of the tiny planet did not
exhibit the typical symmetric U-shaped pattern. It showed an asymmetric
elongated slope pattern that would indicate the presence of a comet-like
tail. Together these features indicated a ring of dusty debris circling
the white dwarf, and what could be the signature of a small planet
being vaporized.
“The eureka moment of discovery came on the last night of observation with a sudden realization of what was going around the white dwarf. The shape and changing depth of the transit were undeniable signatures,” said Vanderburg.
In addition to the strangely shaped transits, Vanderburg and his team found signs of heavier elements polluting the atmosphere of WD 1145+017, as predicted by theory.
Due to intense gravity, white dwarfs are expected to have chemically pure surfaces, covered only with light elements of helium and hydrogen. For years, researchers have found evidence that some white dwarf atmospheres are polluted with traces of heavier elements such as calcium, silicon, magnesium and iron. Scientists have long suspected that the source of this pollution was an asteroid or a small planet being torn apart by the white dwarf's intense gravity.
Analysis of the star's atmospheric composition was conducted using observations made by the University of Arizona's MMT Observatory.
Read more here:http://www.nasa.gov/ames/kepler/nasa-k2-finds-dead-star-vaporizing-mini-planet
“We are for the first time witnessing a miniature “planet” ripped apart by intense gravity, being vaporized by starlight and raining rocky material onto its star,” said Andrew Vanderburg, graduate student from the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, and lead author of the paper published in Nature.
In this artist’s conception, a tiny rocky object
vaporizes as it orbits a white dwarf star. Astronomers have detected the
first planetary object transiting a white dwarf using data from the K2
mission. Slowly the object will disintegrate, leaving a dusting of
metals on the surface of the star.
Credits: CfA/Mark A. Garlick
The devastated planetesimal, or cosmic object formed from dust, rock, and other materials, is estimated to be the size of a large asteroid, and is the first planetary object to be confirmed transiting a white dwarf. It orbits its white dwarf, WD 1145+017, once every 4.5 hours. This orbital period places it extremely close to the white dwarf and its searing heat and shearing gravitational force.
During its first observing campaign from May 30, 2014 to Aug. 21, 2014, K2 trained its gaze on a patch of sky in the constellation Virgo, measuring the minuscule change in brightness of the distant white dwarf. When an object transits or passes in front of a star from the vantage point of the space telescope, a dip in starlight is recorded. The periodic dimming of starlight indicates the presence of an object in orbit about the star.
The diagram depicts a model of light curve shapes.
The red line indicates the symmetric shape of a hypothetical Earth-size
planet transit while the blue line is the asymmetric shape of the tiny
disintegrating planet and its comet-like trailing dusty tail. The black
dots are measurements recorded by the K2 mission of WD 1145+017.
Credits: CfA/A. Vanderburg
“The eureka moment of discovery came on the last night of observation with a sudden realization of what was going around the white dwarf. The shape and changing depth of the transit were undeniable signatures,” said Vanderburg.
In addition to the strangely shaped transits, Vanderburg and his team found signs of heavier elements polluting the atmosphere of WD 1145+017, as predicted by theory.
Due to intense gravity, white dwarfs are expected to have chemically pure surfaces, covered only with light elements of helium and hydrogen. For years, researchers have found evidence that some white dwarf atmospheres are polluted with traces of heavier elements such as calcium, silicon, magnesium and iron. Scientists have long suspected that the source of this pollution was an asteroid or a small planet being torn apart by the white dwarf's intense gravity.
Analysis of the star's atmospheric composition was conducted using observations made by the University of Arizona's MMT Observatory.
Read more here:http://www.nasa.gov/ames/kepler/nasa-k2-finds-dead-star-vaporizing-mini-planet
Red Wolf Still In Texas?
In case you've not checked the blog roll, Cryptomundo
has posted
Red wolf-like animals still in Texas? So if you are interested in canids check it out.
Is It Possible Scientists may have found the earliest evidence of life on Earth?
But you'll notice if you visit the page it's still "maybe"/"might not be"/"Could be"!
When
did life on Earth begin? Scientists have dug down through the geologic
record, and the deeper they look, the more it seems that biology
appeared early in our planet’s 4.5-billion-year history. So far,
geologists have uncovered possible traces of life as far back as 3.8
billion years. Now, a controversial new study presents potential
evidence that life arose 300 million years before that, during the
mysterious period following Earth’s formation.
The clues lie hidden in microscopic flecks of graphite—a carbon mineral—trapped inside a single large crystal of zircon. Zircons grow in magmas, often incorporating other minerals into their crystal structures of silicon, oxygen, and zirconium. And although they barely span the width of a human hair, zircons are nearly indestructible. They can outlast the rocks in which they initially formed, enduring multiple cycles of erosion and deposition.
In fact, although the oldest rocks on Earth date back only 4 billion years, researchers have found zircons up to 4.4 billion years old. These crystals provide a rare glimpse into the first chapter of Earth’s history, known as the Hadean eon. “They are pretty much our only physical samples of what was going on on the Earth before 4 billion years ago,” says Elizabeth Bell, a geochemist at the University of California, Los Angeles (UCLA), and lead author of the new study, published online today in the Proceedings of the National Academy of Sciences.
In the study, Bell and her colleagues examined zircons from the Jack Hills in Western Australia, a site that has yielded more Hadean samples than anywhere else on Earth, searching for inclusions of carbon minerals like diamonds and graphite. The mere presence of these minerals does not prove biology existed when the zircons formed, but it does provide the opportunity to look for chemical signs of life. The team eventually found small bits of potentially undisturbed graphite in one 4.1 billion-year-old crystal. The graphite has a low ratio of heavy to light carbon atoms—called isotopes—consistent with the isotopic signature of organic matter. “On Earth today, if you were looking at this carbon, you would say it was biogenic,” Bell says. “Of course, that’s more controversial for the Hadean.”
The authors list several nonbiological processes that could explain their findings, but they favor the idea that the graphite started out as organic matter in sediments that got dragged into the Earth’s mantle during the collision of tectonic plates. As the sediments melted to form magma, the elevated temperatures and pressures transformed the carbon into graphite, which eventually found its way into a zircon crystal.
If this story is true, and life existed 4.1 billion years ago, Bell says that the new results would corroborate growing evidence of a more hospitable early Earth than scientists once imagined. “The traditional view of the Earth’s first few hundred million years was that this was a sterile, lifeless, hot planet that was constantly being bombarded by meteorites,” she says. But partly thanks to the wealth of information revealed by the Jack Hills zircons in recent years, scientists have come to see the early Earth as much milder and more amenable to life.
“We know there was liquid water,” says Mark van Zuilen, a geomicrobiologist at the Paris Institute of Earth Physics. “There’s nothing that holds us back from assuming life was there.” However, van Zuilen and others say they’re not sure the new study provides compelling evidence that it was.
Some of this circumspection has roots in recent history. In 2008, researchers announced that diamond-graphite inclusions in 4.3-billion-year-old zircons had potentially biological signatures, inspiring Bell and her team to start looking through UCLA’s own collection of Jack Hills crystals. But subsequent analysis showed the 2008 inclusions came from lab contamination, not early Earth. In the new study, the researchers took measures to prevent similar problems.
“That one negative experience doesn’t mean nobody should try again,” says John Eiler, a geologist at the California Institute of Technology in Pasadena. “But let’s just say, I’m cautious.” For one, he says, researchers need to settle some important debates, like whether the inclusions in Hadean zircons truly preserve original material, or if they’ve been altered, for example, during a later bout of metamorphism. He also questions whether organic matter can survive in magma chambers long enough to form graphite, casting doubt on the proposed mechanism.
Those issues aside, most scientists—including the authors—agree that the data do not yet exclude nonbiological explanations. Many abiotic processes can produce carbon with isotopic signatures similar to organic matter. For instance, the graphite could contain carbon from certain kinds of meteorites, which have light isotopic compositions. Alternatively, some invoke chemical processes, like the so-called Fischer-Tropsch reactions, in which carbon, oxygen, and hydrogen react with a catalyst like iron to form methane and other hydrocarbons. Such reactions probably occurred near hydrothermal vents in the Hadean, van Zuilen says, and can impart isotopic signatures that are indistinguishable from biological materials.
One way to settle the question that doesn’t rely on isotopes involves studying Mars, which, unlike Earth, still has rocks older than 4 billion years on its surface. “If we can find evidence for the existence of life on Mars at that time, then it will be easier to argue the case that it was also present on Earth,” says Alexander Nemchin, a geochemist at Curtin University in Bentley, Australia, and lead author of the 2008 study on diamond inclusions.
For now, scientists must make do with zircons, the only materials that preserve any record—however cryptic—of the Hadean eon. Bell acknowledges the need to test her team’s hypothesis on additional samples. She says researchers must make a concerted effort to find more Hadean carbon in Jack Hills zircons and see if it too has potentially biological origins. “Hopefully we didn’t just chance on the one freak zircon that had graphite in it,” she says. “Hopefully there is actually a fair amount of it.”
The clues lie hidden in microscopic flecks of graphite—a carbon mineral—trapped inside a single large crystal of zircon. Zircons grow in magmas, often incorporating other minerals into their crystal structures of silicon, oxygen, and zirconium. And although they barely span the width of a human hair, zircons are nearly indestructible. They can outlast the rocks in which they initially formed, enduring multiple cycles of erosion and deposition.
In fact, although the oldest rocks on Earth date back only 4 billion years, researchers have found zircons up to 4.4 billion years old. These crystals provide a rare glimpse into the first chapter of Earth’s history, known as the Hadean eon. “They are pretty much our only physical samples of what was going on on the Earth before 4 billion years ago,” says Elizabeth Bell, a geochemist at the University of California, Los Angeles (UCLA), and lead author of the new study, published online today in the Proceedings of the National Academy of Sciences.
Image by Robert Simmon, based on data from the University of Maryland’s Global Land Cover Facility
In the study, Bell and her colleagues examined zircons from the Jack Hills in Western Australia, a site that has yielded more Hadean samples than anywhere else on Earth, searching for inclusions of carbon minerals like diamonds and graphite. The mere presence of these minerals does not prove biology existed when the zircons formed, but it does provide the opportunity to look for chemical signs of life. The team eventually found small bits of potentially undisturbed graphite in one 4.1 billion-year-old crystal. The graphite has a low ratio of heavy to light carbon atoms—called isotopes—consistent with the isotopic signature of organic matter. “On Earth today, if you were looking at this carbon, you would say it was biogenic,” Bell says. “Of course, that’s more controversial for the Hadean.”
The authors list several nonbiological processes that could explain their findings, but they favor the idea that the graphite started out as organic matter in sediments that got dragged into the Earth’s mantle during the collision of tectonic plates. As the sediments melted to form magma, the elevated temperatures and pressures transformed the carbon into graphite, which eventually found its way into a zircon crystal.
If this story is true, and life existed 4.1 billion years ago, Bell says that the new results would corroborate growing evidence of a more hospitable early Earth than scientists once imagined. “The traditional view of the Earth’s first few hundred million years was that this was a sterile, lifeless, hot planet that was constantly being bombarded by meteorites,” she says. But partly thanks to the wealth of information revealed by the Jack Hills zircons in recent years, scientists have come to see the early Earth as much milder and more amenable to life.
“We know there was liquid water,” says Mark van Zuilen, a geomicrobiologist at the Paris Institute of Earth Physics. “There’s nothing that holds us back from assuming life was there.” However, van Zuilen and others say they’re not sure the new study provides compelling evidence that it was.
Some of this circumspection has roots in recent history. In 2008, researchers announced that diamond-graphite inclusions in 4.3-billion-year-old zircons had potentially biological signatures, inspiring Bell and her team to start looking through UCLA’s own collection of Jack Hills crystals. But subsequent analysis showed the 2008 inclusions came from lab contamination, not early Earth. In the new study, the researchers took measures to prevent similar problems.
“That one negative experience doesn’t mean nobody should try again,” says John Eiler, a geologist at the California Institute of Technology in Pasadena. “But let’s just say, I’m cautious.” For one, he says, researchers need to settle some important debates, like whether the inclusions in Hadean zircons truly preserve original material, or if they’ve been altered, for example, during a later bout of metamorphism. He also questions whether organic matter can survive in magma chambers long enough to form graphite, casting doubt on the proposed mechanism.
Those issues aside, most scientists—including the authors—agree that the data do not yet exclude nonbiological explanations. Many abiotic processes can produce carbon with isotopic signatures similar to organic matter. For instance, the graphite could contain carbon from certain kinds of meteorites, which have light isotopic compositions. Alternatively, some invoke chemical processes, like the so-called Fischer-Tropsch reactions, in which carbon, oxygen, and hydrogen react with a catalyst like iron to form methane and other hydrocarbons. Such reactions probably occurred near hydrothermal vents in the Hadean, van Zuilen says, and can impart isotopic signatures that are indistinguishable from biological materials.
One way to settle the question that doesn’t rely on isotopes involves studying Mars, which, unlike Earth, still has rocks older than 4 billion years on its surface. “If we can find evidence for the existence of life on Mars at that time, then it will be easier to argue the case that it was also present on Earth,” says Alexander Nemchin, a geochemist at Curtin University in Bentley, Australia, and lead author of the 2008 study on diamond inclusions.
For now, scientists must make do with zircons, the only materials that preserve any record—however cryptic—of the Hadean eon. Bell acknowledges the need to test her team’s hypothesis on additional samples. She says researchers must make a concerted effort to find more Hadean carbon in Jack Hills zircons and see if it too has potentially biological origins. “Hopefully we didn’t just chance on the one freak zircon that had graphite in it,” she says. “Hopefully there is actually a fair amount of it.”
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