IRAS 16293-2422 is a triple protostar
system located in the Rho Ophiuchi star-forming region, which can be
seen in the right corner of this image.
Two teams of astronomers said Thursday that they have for the first time detected a key chemical building block of life swirling around infant stars that resemble our sun before its planets formed.
The molecule, methyl isocyanate, “plays an essential role in the formation of proteins, which are basic ingredients for life,” said Victor Rivilla, a scientist at the Astrophysics Observatory in Florence, Italy, and co-author of a study published in Monthly Notices of the Royal Astronomical Society.
The findings could offer clues on how chemicals sparked into living matter on Earth several billion years ago.
At the very least, they show that elements crucial for the emergence of life “were very likely already available at the earliest stage of solar system formation,” said Niels Ligterink, a researcher at Leiden Observatory in the Netherlands and lead author of a second study in the same journal.
Scientists spotted the organic compound in a dense envelope of interstellar dust and gas circling three young stars some 400 light years from Earth in the constellation Ophiuchus, better known as the Serpent Bearer.
Using the Atacama array of radio telescopes in the northern desert of Chile, the two teams independently isolated the chemical signature of methyl isocyanate and then followed up with computer modeling and laboratory experiments to probe the molecule’s origins.
“Thanks to the amazing capabilities of current telescopes, we are discovering more and more complex organic molecules around the birthplaces of stars and planets,” Rivilla told AFP.
Life-giving, but toxic
Scientists also recently detected sugars in space, including a compound called glycolaldehyde, which plays a role in the formation of DNA structure.
Methyl isocyanate beyond our atmosphere was first discovered two years ago, but in a very different context: near complex, high-mass stars many times bigger than the sun. These are not environments that can yield planetary systems like our own.
Earth and the other planets in our solar system formed some 4.5 billion years ago out of matter left over from the sun.
At this very early stage of evolution, the material feeding the formation of the three-star system described Thursday — known prosaically as IRAS 16293-2422 — is rotating in a disk around each star. Some of the gas and dust will fall to the stars, and the rest will make up the planets.
Paradoxically, methyl isocyanate — and other chemical precursors to life — are highly toxic and potentially lethal to humans and other animals.
Life on Earth may not have been possible without comet strikes.
A new study suggests that about 20 percent of the noble gas xenon in Earth's atmosphere was delivered by comets long ago. And these icy wanderers likely brought lots of other stuff to our planet as well, researchers said.
The "cometary contribution could have been significant for organic matter, especially prebiotic material, and could have contributed to shape the cradle of life on Earth," said study lead author Bernard Marty, a geochemist at the University of Lorraine and the Centre de Recherches Pétrographiques et Géochimiques in France.
Marty and his colleagues studied measurements made by the European Space Agency's (ESA) Rosetta spacecraft, which orbited the 2.5-mile-wide (4 kilometers) Comet 67P/Churyumov-Gerasimenko from August 2014 through September of last year.
Specifically, they analyzed xenon-isotope data that Rosetta gathered during a series of low-altitude orbits of Comet 67P between May 14 and May 31, 2016. (Isotopes are versions of an element that contain different numbers of neutrons in their nuclei. "Heavy" isotopes have more neutrons compared to "lighter" ones.)
Rosetta's observations revealed that 67P is deficient in heavy xenon. Furthermore, the team determined that the comet's xenon isotope composition matches a signature of Earth xenon whose origin had been a mystery.
Rosetta captured this photo of Comet 67P
during the probe's final descent, which culminated in a crash-landing
onto the comet on Sept. 30, 2016.
"These findings establish for the first time a genetic link between comets and the atmosphere of the Earth," Marty told Space.com via email. "This link is not only qualitative but also quantitative, as it permits [us] to decipher for xenon what was the proportion of cometary Xe added to the Earth relative to asteroidal (meteoritic) Xe."
That proportion is 22 percent cometary, plus or minus 5 percent, with asteroids providing the remainder, the researchers report in the new study, which was published online today (June 8) in the journal Science.
Scientists think asteroids delivered the vast majority of the water in Earth's oceans, and these space rocks have been regarded as the chief suppliers of the planet's other "volatiles" — substances with low boiling points, such as nitrogen, carbon dioxide, and noble gases — as well. (Models suggest that Earth was extremely hot shortly after its formation about 4.5 billion years ago, so it probably lost its primordial volatiles early on.)
This inference is drawn partly from the isotopic similarity of hydrogen, nitrogen, and other materials on Earth to that of certain asteroids known as carbonaceous chondrites, as measured in meteorite samples, Marty said.
"There was also a dynamical argument: Jupiter and the other giant planets formed early, and the outer solar system (from which comets originate) was isolated early from the inner solar system by the giant planets' gravitational fields," he said. "Now our finding calls for a revision of such models."
Comets are especially enriched in noble gases, explaining how their contribution of xenon (and perhaps other materials) to the early Earth can be outsized compared to the proportion of water these icy wanderers delivered, Marty added.
The newly analyzed Rosetta data also indicate that 67P's xenon predates the solar system — that is, the comet contains samples of interstellar matter. That's an exciting result that argues for further, more detailed study of pristine cometary material, Marty said.
The lighter green indicates optimistic regions of the habitable zone and the darker green denotes more conservative limits.
A University of Oklahoma post-doctoral astrophysics researcher, Billy Quarles, has identified the possible compositions of the seven planets in the TRAPPIST-1 system. Using thousands of numerical simulations to identify the planets stable for millions of years, Quarles concluded that six of the seven planets are consistent with an Earth-like composition. The exception is TRAPPIST-1f, which has a mass of 25 percent water, suggesting that TRAPPIST-1e may be the best candidate for future habitability studies.
"The goal of exoplanetary astronomy is to find planets that are similar to Earth in composition and potentially habitable," said Quarles. "For thousands of years, astronomers have sought other worlds capable of sustaining life."
Quarles, a researcher in the Homer L. Dodge Department of Physics and Astronomy, OU College of Arts and Sciences, collaborated with scientists, E.V. Quintana, E. Lopez, J.E. Schlieder and T. Barclay at NASA Goddard Space Flight Center on the project. Numerical simulations for this project were performed using the Pleiades Supercomputer provided by the NASA High-End Computing Program through the Ames Research Center and at the OU Supercomputing Center for Education and Research.
TRAPPIST-1 planets are more tightly spaced than in Kepler systems, which allow for transit timing variations with the photometric observations. These variations tell the researchers about the mass of the planets and the radii are measured through the eclipses. Mass and radius measurements can then infer the density. By comparing Earth's density (mostly rock) to the TRAPPIST-1 planets, Quarles can determine what the planets are likely composed of and provide insight into whether they are potentially habitable.
TRAPPIST-1f has the tightest constraints with 25 percent of its mass in water, which is rare given its radius. The concern of this planet is that the mass is 70 percent the mass of Earth, but it is the same size as Earth. Because the radius is so large, the pressure turns the water to steam, and it is likely too hot for life as we know it. The search for planets with a composition as close to Earth's as possible is key for finding places that we could identify as being habitable. Quarles said he is continually learning about the planets and will investigate them further in his studies.
TRAPPIST-1 is a nearby ultra-cool dwarf about 40 light-years away from Earth and host to a remarkable planetary system consisting of seven transiting planets. The seven planets are known as TRAPPIST 1b, c, d, e, f, g and h.
This is a 3-D model of the virtual reconstruction of the bony labyrinth, which will be available for online visualization.
Whales rely on a keen sense of hearing for their underwater existence. But whales show surprisingly vast differences in hearing ability. Baleen whales tune into infrasonic sounds -- at frequencies too low for humans to hear -- to communicate over long distances. Toothed whales do just the opposite, relying on ultrasonic frequencies too high for humans to hear.
Now researchers reporting in Current Biology on June 8 have fossil evidence from extinct early whale species to suggest that those differences in hearing arose only after whales evolved into the fully aquatic animals we know today. That's based on their findings that whales known as protocetes, which spent time both in water and on land, appear to have hearing more like their terrestrial, even-toed ungulate relatives, including pigs, hippos, and camels.
"We found that the cochlea of protocetes was distinct from that of extant whales and dolphins and that they had hearing capacities close to those of their terrestrial relatives," says Maeva Orliac of CNRS and Université de Montpellier in France.
Protocetes' lack of hearing specialization suggests that the early whales were unable to echolocate and communicate through long-distance calls in the way that modern-day cetaceans, the group including whales and dolphins, do.
The researchers came to those conclusions based on studies of 45-million-year-old protocetid whale remains found in marine deposits from Togo in West Africa. The researchers studied the bony labyrinth, a hollow cavity that would have housed the hearing organ, in two species of early whales.
Orliac and her colleague Mickaël Mourlam used micro-CT scanning to peer inside the internal structures of rocks and fossils, in much the same way that an X-ray scanner makes it possible to see bones inside a person's body. Those images allowed them to analyze the internal cavities of the petrosal bone, which shelters the organs of hearing and balance.
"Based on the scans provided by the scanner, we could extract a virtual mold of the hollow cavity that used to contain the hearing organ when the animal was alive," Orliac says. "This process was long and difficult because this cavity was filled with sediments and partly recrystallized and because the petrosal bone in cetaceans is particularly thick and dense, which lowers the quality of the images and sometimes impedes analyzing them."
Nevertheless, the scans suggest that early cetaceans had hearing closer to that of their terrestrial relatives. Specialization to infrasonic or ultrasonic hearing as seen in modern whales came only later, in whales that had already found their way back to the sea.
The findings highlight the importance of studying these early cetaceans to get an accurate picture of whales' evolutionary history. It also suggests that whales' evolutionary past is more complicated than had previously been described, the researchers say.
ALMA has observed stars like the Sun at a very early stage in their
formation and found traces of methyl isocyanate -- a chemical building
block of life. This is the first ever detection of this prebiotic
molecule towards a solar-type protostar, the sort from which our Solar
System evolved. The discovery could help astronomers understand how life
arose on Earth. This image shows the spectacular region of star
formation where methyl isocyanate was found. The insert shows the
molecular structure of this chemical.
Two teams of astronomers have harnessed the power of the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile to detect the prebiotic complex organic molecule methyl isocyanate in the multiple star system IRAS 16293-2422. One team was co-led by Rafael Martín-Doménech at the Centro de Astrobiología in Madrid, Spain, and Víctor M. Rivilla, at the Osservatorio Astrofisico di Arcetri in Florence, Italy; and the other by Niels Ligterink at the Leiden Observatory in the Netherlands and Audrey Coutens at University College London, United Kingdom.
"This star system seems to keep on giving! Following the discovery of sugars, we've now found methyl isocyanate. This family of organic molecules is involved in the synthesis of peptides and amino acids, which, in the form of proteins, are the biological basis for life as we know it," explain Niels Ligterink and Audrey Coutens.
ALMA's capabilities allowed both teams to observe the molecule at several different and characteristic wavelengths across the radio spectrum. They found the unique chemical fingerprints located in the warm, dense inner regions of the cocoon of dust and gas surrounding young stars in their earliest stages of evolution. Each team identified and isolated the signatures of the complex organic molecule methyl isocyanate. They then followed this up with computer chemical modelling and laboratory experiments to refine our understanding of the molecule's origin.
IRAS 16293-2422 is a multiple system of very young stars, around 400 light-years away in a large star-forming region called Rho Ophiuchi in the constellation of Ophiuchus (The Serpent Bearer). The new results from ALMA show that methyl isocyanate gas surrounds each of these young stars.
Earth and the other planets in our Solar System formed from the material left over after the formation of the Sun. Studying solar-type protostars can therefore open a window to the past for astronomers and allow them to observe conditions similar to those that led to the formation of our Solar System over 4.5 billion years ago.
Rafael Martín-Doménech and Víctor M. Rivilla, lead authors of one of the papers, comment: "We are particularly excited about the result because these protostars are very similar to the Sun at the beginning of its lifetime, with the sort of conditions that are well suited for Earth-sized planets to form. By finding prebiotic molecules in this study, we may now have another piece of the puzzle in understanding how life came about on our planet."
An ancient, rectangular copper mask recently found in the southern Andes in Argentina is about 3,000 years old — one of the oldest human-made metal objects from South America — and its discovery challenges the accepted idea that South American metalworking originated in Peru, according to archaeologists.
Found at a site where adults and children were buried, the mask dates to approximately 1000 B.C., the scientists wrote in a study describing the find. Holes mark the position of the mask's eyes, nose and mouth, with additional small, circular openings near the edges that could have been threaded to secure it to a face or an object.
Sources of copper ore have been found within 44 miles (70 kilometers) of the location where the mask was uncovered, suggesting that it was produced locally. It is therefore highly probably that metalworking emerged in Argentina at the same time that it was developing in Peru, the researchers wrote in the study.
Gold objects estimated to be nearly 4,000 years old have been found in southern Peru, according to a study published in February 2008 in the journal Proceedings of the National Academy of Sciences. Bronze artifacts dating to about A.D. 1000 were previously found in the Peruvian Andes, though it is difficult for experts to say for sure if the objects originated where they were found, or if trade brought them there, Live Science reported in 2007. But evidence of local metalworking in Peru still lingers — in trace metals found in local sediments, dating to pre-Incan times, scientists also learned in 2007.
Weather during the summer rainy season exposed the metal mask — along with a collection of human bones — in a tomb near the village of La Quebrada, in northwestern Argentina, the study authors wrote. There were about 14 bodies in the burial area, with the bones all mixed together and the mask placed on top of one corner of the pile.
Nearby, a second burial area held a single occupant. The bones of a child approximately 8 to 12 years old, also dating to about 3,000 years ago, were buried with a stone bead and with what appeared to be a copper pendant, perforated by a small hole near the top.
The mask measures about 7 inches (18 centimeters) long and nearly 6 inches (15 cm) wide. Impurities in the copper are lower than 1 percent. To create the mask, someone would have hammered the metal flat while it was cold and then reheated it, according to the researchers.
The age of these metal objects — particularly the mask, crafted to deliberately resemble a human face — strongly suggests that people in the Argentinian regions of the Andes were shaping copper into artifacts earlier than previously thought, the study authors noted.
"Proof of copper smelting and annealing [a process of cooling metal slowly to make it stronger] further highlights the northwest Argentinian valleys and northern Chile as early centers in the production of copper," the researchers wrote.
Hubble Space Telescope image showing the close passage of the nearby white dwarf Stein 2051 B in front of a distant source star.
Scientists have confirmed one of Albert Einstein’s century-old theories by witnessing a phenomenon with the Hubble Space Telescope that he thought would be impossible to see, researchers declared Wednesday.
Astronomers have now glimpsed for the first time a distant star’s light bending and revealing its mass when an object passes in front of it, known as “gravitational microlensing,” said the report, which was published in the journal Science.
“Einstein would be proud. One of his key predictions has passed a very rigorous observational test,” wrote Terry Oswalt of Embry-Riddle Aeronautical University, in an accompanying Perspective article in Science.
This gravitational microlensing was seen in 1919, when starlight curved around a total eclipse of the sun. At the time, the discovery offered some of the first convincing proof for Einstein’s theory of general relativity — a law of physics that describes gravity as a geometric function of both space and time.
“When a star in the foreground passes exactly between us and a background star, gravitational microlensing results in a perfectly circular ring of light — a so-called ‘Einstein ring,’” said Oswalt.
But Einstein believed that it would not be possible to see the phenomenon with stars other than our sun. In a 1936 article in Science, he wrote that because stars are so far apart “there is no hope of observing this phenomenon directly.”
Of course, Einstein could not have predicted that the Hubble Space Telescope would be launched in 1990 and offer unprecedented views of faraway stars and planets.
Fossil of a star
Using Hubble, an international research team directed by Kailash C. Sahu of the Space Telescope Science Institute in Baltimore, Maryland, focused on a distant star as its light was deflected around a nearby white dwarf star called Stein 2051 B.
A white dwarf is the remnant of a star that has completed its hydrogen-burning life cycle, and is a fossil of the prior generations of stars in our galaxy. Stein 2051 B is the sixth-closest white dwarf star to the sun, and researchers discovered it has a mass about two-thirds that of the sun.
The deflection of the background star’s light is directly related to the mass and gravity of the white dwarf.
The first known fossilized skin impressions for Tyrannosaurus rex suggest that this gigantic carnivore, unlike many other dinosaurs, had little to no feathers.
The fossils, reported in the journal Biology Letters, show that T. rex was instead covered with a tough and scaly hide. Fossilized skin impressions for other tyrannosaurs — including Albertosaurus, Gorgosaurus, and Daspletosaurus — reveal that all such dinosaurs lacked feathers, too.
Co-author W. Scott Persons and his colleagues were thrilled when they first saw the T. rex remains, which preserve numerous patches of skin impressions from the dinosaur’s neck, pelvis, and tail.
“Mostly I couldn’t wait to touch it!” Persons said, referring to one such well-preserved fossil. “It is every kid’s dream to pet a T. rex, and — if we are honest — it is also every dinosaur paleontologist’s.”
“The skin is bumpy,” he continued. “None of the scales are as big as what you see on the back of a crocodile, but they are similar to the scales along a croc’s flank. I suppose tyrannosaur hide would make for a nice set of luggage.”
The T. rex remains were unearthed near the town of Baker, Montana, and date to the Late Cretaceous (100.5–66 million years ago). Lead author Phil Bell of the University of New England, Persons, and the rest of the international team examined the fossils in detail. The resulting information, combined with observations of the other dinosaur remains, allowed the researchers to assemble a new dataset concerning both tyrannosaur skin and overall body size.
The scientists note that the wolf and lion-sized ancestors of tyrannosaurs were among the first carnivorous dinosaurs to be discovered with feathered, rather than scaled, skin. Over the course of evolution, many in the lineage must have therefore lost their feathers.
Persons said that the feather coats of the tyrannosaur ancestors probably served as insulation to hold in body heat. As T. rex and certain other tyrannosaurs grew ever larger over time, their need for feathers probably diminished.
Tyrannosaur fossil skin impression.
“Today we see that many big mammals — like elephants, rhinos, hippos, and Cape buffalo — have greatly reduced their covering of hair,” he explained. “As big bulky animals living in warm environments, these mammals are more concerned with the risk of overheating than the challenge of staying warm, so they are better off with little to no hair. The same explanation probably explains, at least in part, why big tyrannosaurids had little to no feathers.”
T. rex, which could grow to about 40 feet long and 20 feet tall, had very long legs and strong leg bones. These indicate that it could move quickly when it wanted to do so.
“In a sprint, it could probably out-run any other large dinosaur,” Persons said.
T. rex, as well as other tyrannosaurs, lived in a range of habitats, from swamps to open floodplains. During the day, these regions could become very hot. A large animal with an active lifestyle living in an often-hot environment was then “better off not wearing a down jacket,” Persons said.
Exchanging such a feathery covering for a scaly hide meant that T. rex and its kind were covered in skin that was tough and resistant to abrasion, the researchers believe.
Persons is currently investing still more new T. rex fossils, this time from Saskatchewan, Canada. Instead of focusing on the skin, he is examining the enormous dinosaur’s skull, and what it reveals about the carnivore’s face.
When pilgrims lined up in a church in northern Italy to pray before the relic of St. John Bosco, the revered founder of the Salesian religious order, on Saturday (June 3), they encountered a sign with an unexpected message: "Closed. Under construction."
However, it was clear that no construction work was going on in the church, called the basilica of Castelnuovo, located near Turin. And so, as pressure mounted over the puzzling sign, the church revealed a shocking truth: Someone had stolen preserved brain bits of a saint.
"The relic of St. Bosco has been stolen," Rev. Moreno Filipetto, a spokesman for the Salesian religious order, said in a statement. "To avoid hindering the ongoing police investigation, no other information will be provided."
The mysterious theft probably occurred just before the basilica's closing time on Friday (June 2), according to reports in Turin's newspaper, La Stampa. The thief, disguised as a pilgrim, likely just walked out of the church with a glass case containing pieces of the preserved brain of St. John Bosco, popularly known as Don Bosco, La Stampa reported.
Satanic rituals or ransom may lie behind the theft, according to reports in the Italian press.
"We do not really know why the relic was stolen," Filipetto told Live Science in Italian. "We have the utmost trust in the work of the police; they are working hard on the case."
Preserved brain pieces of St. John Bosco are kept at the basilica of Castelnuovo, near Turin, Italy.
However, Filipetto said he could not confirm the details of the case.
Indeed, the case is still a mystery, said Fr Francesco Cereda, vicar of the Rector Major. (Cereda is the vicar, who takes the Rector Major's place whenever he is absent or impeded; he's second from the top of this Salesian hierarchy.)
"To date, there is nothing new in the investigations regarding those responsible for the theft of Don Bosco's relics," Cereda said.
Born in Castelnuovo, Italy, on Aug. 16, 1815, Don Bosco devoted his life to helping deprived children. In 1859, he founded the Society of St. Francis de Sales, better known as the Salesians or Salesians of Don Bosco, to help the poor and homeless children during the Industrial Revolution. The religious order has grown to become the second-largest order in the Catholic Church. According to Salesian Missions, the order is regarded as the single largest provider of vocational and technical training in the world, operating more than 3,200 schools and technical training centers, more than 70 colleges, more than 90 clinics and a hospital, and more than 330 orphanages and shelters.
Don Bosco died in 1888 and was canonized in 1934 by Pope Pius XI. He is one of the most venerated saints, and each year, more than 600,000 pilgrims visit the basilica of Castelnuovo, according to La Stampa.
Body parts belonging to holy figures are often displayed in Catholic churches as "tangible elements to favor the invocation of the saint," Cereda said. "Don Bosco is loved and invoked for the young people, especially the poor and marginalized," he added, referring to invocations, or prayers.
Even moderate drinking is linked to brain damage and a slight decline in mental skills, according to a study released Wednesday that calls into question many national alcohol guidelines.
Men and women who consume 14-to-21 drinks a week over decades are two to three times more likely than non-drinkers to show atrophy in the hippocampus, a part of the brain that governs memory and the ability to keep one’s bearings, said the study, which was published in the medical journal BMJ.
They also performed more poorly on a specific verbal test, though other language functions appeared to remain unchanged.
A single drink was defined as containing 10 milliliters (eight grams) of pure alcohol — the equivalent of a large glass of wine, a pint of five-percent beer, or a shot of spirits such as whisky or vodka.
Last year, the British government revised its guidelines for alcohol consumption, lowering the recommended maximum for men and women to 14 “units,” or drinks, spread out over a week. In other countries, that threshold is set higher for men: 35 units in Spain, 24.5 in the United States, 21 in Denmark and Ireland, and 19 in New Zealand.
For women, however, guidelines for maximum weekly consumption in all of these nations, except for Spain, is 14 drinks or less.
The negative impact of heavy drinking on the brain is well documented, but research on potential damage from “moderate” consumption — up to now defined as two or three drinks a day, on average — has been scant and inconclusive.
To probe further, researchers at the University of Oxford and University College London combed through data on 550 men and women monitored during 30 years as part of the so-called Whitehall II study. Volunteers reported periodically on their drinking habits, and scientists carried out brain tests at regular intervals. None were alcoholics at the outset.
The effect of 14-to-21 units of alcohol on the hippocampus was clearly shown by imaging technology.
‘Hidden damage’
Mental performance tests were less conclusive: Only one measuring language fluency showed a clear impact, while others showed no decline in brain function.
“Alcohol consumption — even at moderate levels — is associated with adverse brain outcomes,” the researchers concluded.
The findings “support the recent reduction in alcohol guidance in the United Kingdom, and question the current limits recommended in the United States,” they wrote.
Nor did the scientists uncover any “evidence of a protective effect of light drinking over abstinence on brain structure or function,” a tentative conclusion of earlier research.
Because the new study was observational and not experimental, no firm conclusions could be drawn about cause and effect. The authors also acknowledged that the sample size was small.
Outside experts gave the study mixed reviews.
“It shows evidence for ‘hidden’ damage to the brain,” commented Paul Matthews of Imperial College London, who highlighted the value of the advanced imaging techniques used.
Jennifer Wild, a senior researcher in clinical psychology at the University of Oxford, said the results showed a “robust link” between what most people would consider casual drinking and brain degeneration later in life.
A composite reconstruction of the earliest
known Homo sapiens fossils from Jebel Irhoud, Morocco based on micro
computed tomographic scans of multiple original fossils. Dated to 300
thousand years ago, these early Homo sapiens already have a
modern-looking face that falls within the variation of humans living
today. However, the archaic-looking braincase indicates that brain
shape, and possibly brain function, evolved within the Homo sapiens
lineage.
In 1971, anthropologist Chris Stringer traveled to museums across Europe to study and measure as many Neanderthal skulls as possible for his Ph.D. One enigmatic fossil, described as an “African Neanderthal” and dated to 40,000 years ago, particularly intrigued him. Thanks to a tip shared over coffee in Paris, he found the skull stored in another anthropologist’s cupboard.
Stringer was very puzzled by what he saw.
“I knew it was no Neanderthal,” recalled Stringer, who is now a Merit Researcher at the Natural History Museum in London. “It completely lacked their puffed-out cheek bones, mid-facial prominence, and enormous nose.”
Over the years, the fossil puzzled other scientists as well. A new excavation project began in 2004 at the site where the “African Neanderthal” was found in the 1960s — Jebel Irhoud, located west of Marrakesh in Morocco. Two new papers published in Nature report the astonishing results of this lengthy project: The so-called Neanderthal and related fossils turn out to be 300,000–350,000-year-old Homo sapiens, making them the oldest known remains for our species.
The twenty-two Homo sapiens fossils discovered so far at Jebel Irhoud push back the origins of our species by over one hundred thousand years. To put this into perspective, the prior oldest securely dated Homo sapiens fossils were known from the site of Omo Kibish in Ethiopia, and were dated to 195,000 years ago.
“Even though the Jebel Irhoud fossils currently represent the oldest Homo sapiens fossil remains, we do not believe that North Africa is the ‘cradle of humankind,’” Philipp Gunz, senior author of the first of the two papers, said.
“Instead, we argue that the first Homo sapiens dispersed all over the African continent around 300,000 years ago,” added Gunz, who is a paleoanthropologist in the Department of Human Evolution at the Max Planck Institute for Evolutionary Anthropology (MPI-EVA). “These people were skilled hunters, so it is likely that they moved with their prey in the changing environments of Africa.”
View looking south of the Jebel Irhoud,
Morocco site. The remaining deposits and several people excavating them
are visible in the center. At the time the site was occupied by early
hominins, it would have been a cave, but the covering rock and much
sediment were removed by work at the site in the 1960s.
The evidence for such hunting consists of stone tools and animal remains that were found at the site with the human fossils — skulls, teeth, and long bones — that belonged to at least five individuals.
Shannon McPherron, senior author of the second paper, explained that the stone tools belong to what is known as the Middle Stone Age. Prior to this time, the predecessors of modern humans — who, with our species, comprise a group called hominins — largely relied upon big and heavy stone tools, such as hand-axes and cleavers. In the Middle Stone Age, they developed lighter and smaller tools, such as sharp pointed objects.
McPherron, an archaeologist at MPI-EVA, said many experts “think that some of the points would have served as spear points, and this would have made these Middle Stone Age peoples more effective hunters.”
Two of the new Jebel Irhoud, Morocco
fossils in situ as they were discovered during excavation. In the center
of the image, in a slightly more yellow brown tone, is the crushed top
of a human skull (Irhoud 10) and visible just above this is a partial
femur (Irhoud 13) resting against the back wall. Not visible behind the
pointed rock (between the femur and the skull) is the mandible (Irhoud
11). The scale is in centimeters.
Based on the animal remains, the early humans’ prey of choice were gazelles. Fossilized zebras, wildebeest, and hartebeest were also found at the Jebel Irhoud archaeological cave site.
The ages of the finds were determined by thermoluminescence dating of the flint artifacts, which had been heated by fire. Daniel Richter of MPI-EVA, lead author of the second paper who directed the dating work, remembered how amazed he was when the results came in.
“When I first calculated the first ages, I couldn’t believe it and re-checked all parameters several times until I was sure that my thermoluminescence ages are alright,” Richter said.
Electron spin resonance dating was also employed, and was in agreement with the other results.
Middle Stone Age tool assemblages, similar to those at Jebel Irhoud, have been found throughout Africa, supporting Gunz’s statement that early Homo sapiens were nomadic hunters. Ecological barriers, such as the vast Sahara that experiences a “greening” wet period associated with plant growth every 15,000 or so years, likely played an important role in the evolution of our species. (The Sahara is currently in a dry period.)
Some of the Middle Stone Age stone tools from Jebel Irhoud, Morocco. Pointed forms such as a–i are common in the assemblage.
“This ancient population structure might explain why Homo sapiens are so diverse, despite being so closely related genetically,” Gunz said.
Jean-Jacques Hublin, who is lead author of the first paper, Gunz, and their colleagues used state-of-the-art micro computed tomographic scans and statistical shape analysis based on hundreds of 3D measurements to show that the facial shape of the Jebel Irhoud fossils is almost indistinguishable from that of modern humans living today. The methods further indicate that a partial cranium from Florisbad, South Africa, and now dated to 260,000 years ago also belonged to a Homo sapiens.
It is little wonder then that Stringer was so puzzled by the Jebel Irhoud skull that was once incorrectly labeled as being an “African Neanderthal.”
Stringer notes that the human skulls from the Moroccan site show that these early Homo sapiens had delicate cheekbones versus those of other primates and hominins. They also possessed retracted faces and jawbones like those of people today.
The excavation area is visible as a dark notch a little more than half way down the ridge line sloping to the left.
The Moroccan human fossils, however, also reveal more primitive features, such as a longer, lower braincase, strong brow-ridges, and a larger face and teeth than what individuals have now. The braincase evidence is particularly important, as many anthropologists suspect that a series of genetic changes affecting brain connectivity, organization, and development occurred in Homo sapiens, distinguishing our species from our extinct ancestors and relatives.
Intriguingly, Stringer indicated that the fossils share some features with the remains of a hominin known as “Galilee Man” from a site called “Cave of the Robbers” of about the same age in Israel. They also share features with other hominin remains unearthed at yet another Israeli site, Tabun Cave, a rock shelter located on the edge of the coastal Mount Carmel mountain range.
While the preponderance of genetic and fossil record evidence support that the evolution of Homo sapiens took place in Africa, fossils also show that the earliest known primates originated in Asia more than 40 million years ago.
Fossils for a human-ish species called “El Graeco” from the Eastern Mediterranean were recently determined to represent the oldest known hominin. The point at which humanity diverged from other primates could have then happened in this region.
An illustration of El Graeco, foreground, living in a savannah environment in the Eastern Mediterranean 7.2 million years ago.
If such an event occurred outside of Africa, then the common ancestor of Homo sapiens, Neanderthals and Denisovans might have lived outside of Africa too, but that mystery remains unsolved.
A clearer picture is emerging concerning what happened in Africa, however.
“Twenty years ago, I thought that Homo sapiens had a rapid and punctuational origin in a single location in Africa, perhaps East Africa,” Stringer said. “Now, I think it’s more like a multiregional evolution of sapiens within Africa, with different populations separated in different regions in the bad times — with some going extinct — and connecting up and exchanging genes and behaviors in the good times, climatically speaking.”
Astronomers at The Ohio State University and Vanderbilt University have
discovered a planet that is so hot, its temperature rivals most stars.
A newly discovered Jupiter-like world is so hot that it's stretching the definition of the word "planet."
With a day-side temperature of 4,600 Kelvin (more than 7,800 degrees Fahrenheit), planet KELT-9b is hotter than most stars, and only 1,200 Kelvin (about 2,000 degrees Fahrenheit) cooler than our own sun.
In this week's issue of the journal Nature and at a presentation at the American Astronomical Society spring meeting, an international research team led by astronomers at The Ohio State University and Vanderbilt University describes a planet with some very unusual features.
For instance, it's a gas giant 2.8 times more massive than Jupiter but only half as dense, because the extreme radiation from its host star has caused its atmosphere to puff up like a balloon. And because it is tidally locked to its star -- as the Moon is to Earth -- the day side of the planet is perpetually bombarded by stellar radiation, and as a result is so hot that molecules such as water, carbon dioxide, and methane can't form there. The properties of the night side are still mysterious -- molecules may be able to form there, but probably only temporarily.
"It's a planet by any of the typical definitions based on mass, but its atmosphere is almost certainly unlike any other planet we've ever seen just because of the temperature of its day side," said Scott Gaudi, professor of astronomy at The Ohio State University and a leader of the study.
KELT-9b orbits a star, dubbed KELT-9, which is more than twice as large and nearly twice as hot as our sun. Keivan Stassun, a professor of physics and astronomy at Vanderbilt who directed the study with Gaudi said, "KELT-9 radiates so much ultraviolet radiation that it may completely evaporate the planet. Or, if gas giant planets like KELT-9b possess solid rocky cores as some theories suggest, the planet may be boiled down to a barren rock, like Mercury."
That is, if the star doesn't grow to engulf it first. "KELT-9 will swell to become a red giant star in about a billion years," said Stassun. "The long-term prospects for life, or real estate for that matter, on KELT-9b are not looking good."
Given that its atmosphere is constantly blasted with high levels of ultraviolet radiation, the planet may even be shedding a tail of evaporated planetary material like a comet, Gaudi added.
While Gaudi and Stassun spend a lot of time developing missions designed to find habitable planets in other solar systems, the scientists said there's a good reason to study worlds that are unlivable in the extreme.
"As has been highlighted by the recent discoveries from the MEarth collaboration, the planet around Proxima Centauri, and the astonishing system discovered around TRAPPIST-1, the astronomical community is clearly focused on finding Earthlike planets around small, cooler stars like our sun. They are easy targets and there's a lot that can be learned about potentially habitable planets orbiting very low-mass stars in general. On the other hand, because KELT-9b's host star is bigger and hotter than the sun, it complements those efforts and provides a kind of touchstone for understanding how planetary systems form around hot, massive stars," Gaudi said.
Stassun added, "As we seek to develop a complete picture of the variety of other worlds out there, it's important to know not only how planets form and evolve, but also when and under what conditions they are destroyed."
How was this new planet found?
In 2014, astronomers using the KELT-North telescope at Winer Observatory in Arizona noticed a tiny drop in the star's brightness -- only about half of one percent -- that indicated that a planet may have passed in front of the star. The brightness dipped once every 1.5 days, which means the planet completes a "yearly" circuit around its star every 1.5 days.
Subsequent observations confirmed the signal to be due to a planet, and revealed it to be what astronomers call a "hot Jupiter" -- the ideal kind of planet for the KELT telescopes to spot.
KELT is short for "Kilodegree Extremely Little Telescope." Astronomers at Ohio State, Vanderbilt University, and Lehigh University jointly operate two KELTs (one each in the Northern and Southern Hemispheres) in order to fill a large gap in the available technologies for finding extrasolar planets.
Other telescopes are designed to look at very faint stars in much small sections of the sky, and at very high resolution. The KELTs, in contrast, look at millions of very bright stars at once, over broad sections of sky, and at low resolution.
It's a low-cost means of planet hunting, using mostly off-the-shelf technology: whereas a traditional astronomical telescope costs millions of dollars to build, the hardware for a KELT telescope runs less than $75,000.
"This discovery is a testament to the discovery power of small telescopes, and the ability of citizen scientists to directly contribute to cutting-edge scientific research," said Joshua Pepper, astronomer and assistant professor of physics at Lehigh University, who built the two KELT telescopes.
The astronomers hope to take a closer look at KELT-9b with other telescopes -- including Spitzer, the Hubble Space Telescope (HST), and eventually the James Webb Space Telescope. Observations with HST would enable them to see if the planet really does have a cometary tail, and allow them to determine how much longer that planet will survive its current hellish condition.
Study co-authors from Ohio State include Daniel J. Stevens, Marshall C. Johnson, Matthew Penney, Andrew Gould and Richard Pogge, all of the Department of Astronomy.
American partner institutions include Vanderbilt University, Fisk University, Pennsylvania State University, the Harvard-Smithsonian Center for Astrophysics, Las Cumbres Observatory Global Telescope Network, University of Notre Dame, Lehigh University, NASA Ames Research Center, Bay Area Environmental Research Institute, Swarthmore College, IPAC, Brigham Young University, University of California-Santa Cruz, University of Wyoming, Louisiana State University, University of Louisville, Spot Observatory in Nashville, Westminster College, Kutztown University, University of Hawaii, University of Washington, Texas A&M University, Wellesley College, and Winer Observatory in Sonoita, AZ. International team members are from Denmark, Italy, Japan, Portugal, Switzerland, Australia, Germany and South Africa.
This diagram compares Hubble Space Telescope observations of two "hot
Jupiter"-class planets orbiting very closely to different sunlike stars.
Astronomers measured how light from each parent star is filtered
through each planet's atmosphere. HAT-P-38 b did have a water signature
indicated by the absorption-feature peak in the spectrum. This is
interpreted as indicating the upper atmosphere is free of clouds or
hazes. WASP-67 b, has a flat spectrum that lacks any water-absorption
feature, suggesting most of the planet's atmosphere is masked by
high-altitude clouds.
Is it a case of nature versus nurture when it comes to two "cousin" exoplanets? In a unique experiment, scientists used NASA's Hubble Space Telescope to study two "hot Jupiter" exoplanets. Because these planets are virtually the same size and temperature, and orbit around nearly identical stars at the same distance, the team hypothesized that their atmospheres should be alike. What they found surprised them.
Lead researcher Giovanni Bruno of the Space Telescope Science Institute in Baltimore, Maryland, explained, "What we're seeing in looking at the two atmospheres is that they're not the same. One planet -- WASP-67 b -- is cloudier than the other -- HAT-P-38 b. We don't see what we're expecting, and we need to understand why we find this difference."
The team used Hubble's Wide Field Camera 3 to look at the planets' spectral fingerprints, which measure chemical composition. "The effect that clouds have on the spectral signature of water allows us to measure the amount of clouds in the atmosphere," Bruno said. "More clouds mean that the water feature is reduced." The teams found that for WASP-67 b there are more clouds at the altitudes probed by these measurements.
"This tells us that there had to be something in their past that is changing the way these planets look," said Bruno.
Today the planets whirl around their yellow dwarf stars once every 4.5 Earth days, tightly orbiting their stars closer than Mercury orbits our sun. But in the past, the planets probably migrated inward toward the star from the locations where they formed.
Perhaps one planet formed differently than the other, under a different set of circumstances. "You can say it's nature versus nurture," explains co-investigator Kevin Stevenson. "Right now, they appear to have the same physical properties. So, if their measured composition is defined by their current state, then it should be the same for both planets. But that's not the case. Instead, it looks like their formation histories could be playing an important role."
The clouds on these hot, Jupiter-like gas giants are nothing like those on Earth. Instead, they are probably alkali clouds, composed of molecules such as sodium sulfide and potassium chloride. The average temperature on each planet is more than 1,300 degrees Fahrenheit.
The exoplanets are tidally locked, with the same side always facing the parent star. This means they have a very hot day-side and a cooler night-side. Instead of sporting multiple cloud bands like Jupiter does, each probably has just one broad equatorial band that slowly moves the heat around from the day-side to the night-side.
A new study reconfigures the elephant family tree, placing the giant
extinct elephant Palaeoloxodon antiquus closer to the African forest
elephant, Loxodonta cyclotis, than to the Asian elephant, Elephas
maximus, which was once thought to be its closest living relative.
New research reveals that a species of giant elephant that lived 1.5 million to 100,000 years ago -- ranging across Eurasia before it went extinct -- is more closely related to today's African forest elephant than the forest elephant is to its nearest living relative, the African savanna elephant.
The study challenges a long-held assumption among paleontologists that the extinct giant, Palaeoloxodon antiquus, was most closely related to the Asian elephant. The findings, reported in the journal eLife, also add to the evidence that today's African elephants belong to two distinct species, not one, as was once assumed.
Understanding their genetic heritage is key to keeping today's elephants from going extinct, said University of Illinois animal sciences professor Alfred Roca, a co-author of the new study. Roca led research in the early 2000s that provided the first genetic evidence that African elephants belonged to two distinct species. Subsequent studies have confirmed this, as does the new research.
"We've had really good genetic evidence since the year 2001 that forest and savanna elephants in Africa are two different species, but it's been very difficult to convince conservation agencies that that's the case," Roca said. "With the new genetic evidence from Palaeoloxodon, it becomes almost impossible to argue that the elephants now living in Africa belong to a single species."
For the new analysis, scientists looked at two lines of evidence from African and Asian elephants, woolly mammoths and P. antiquus. They analyzed mitochondrial DNA, which is passed only from mothers to their offspring, and nuclear DNA, which is a blend of paternal and maternal genes.
The researchers relied on the most sensitive laboratory techniques to extract and amplify the DNA in P. antiquus bones from two sites in Germany -- among the first DNA successfully collected from such ancient bones from a temperate climate.
"Up until now, genetic research on bones that are hundreds of thousands of years old has almost exclusively relied on fossils collected in permafrost," said Matthias Meyer, a researcher from the Max Planck Institute for Evolutionary Anthropology and first author of the paper. "It is encouraging to see that recent advances in laboratory methods are now enabling us to recover very old DNA sequences also from warmer places, where DNA degrades at a much faster rate."
The mitochondrial analysis revealed that a shared ancestor of P. antiquus and the African forest elephant lived sometime between 1.5 million and 3.5 million years ago. Their closest shared ancestor with the African savanna elephant lived between 3.9 and 7 million years ago.
The nuclear DNA told the same story, the researchers report.
"From the study of bone morphology, people thought Palaeoloxodon was closer to the Asian elephant. But from the molecular data, we found they are much closer to the African forest elephant," said research scientist Yasuko Ishida, who led the mitochondrial sequencing of modern elephants with Roca.
"Palaeoloxodon antiquus is a sister to the African forest elephant; it is not a sister to the Asian elephant or the African savanna elephant," Roca said.
"Paleogenomics has already revolutionized our view of human evolution, and now the same is happening for other mammalian groups," said study co-author Michael Hofreiter from the University of Potsdam, an expert on evolutionary genomics. "I am sure elephants are only the first step and in the future, we will see surprises with regard to the evolution of other species as well."Michael
Understanding the genetic heritage of elephants is vital to protecting the living remnant populations in Africa and beyond, Roca said.
It's been around 11,000 years since giant ground sloths roamed North America, but evidence of one of them recently surfaced in Los Angeles, during excavation for a transit project managed by the LA County Metropolitan Transportation Authority.
Fossils from a giant sloth and a bison were unearthed on May 16 in a layer of sandy clay about 16 feet (5 meters) below Crenshaw Boulevard between 63rd Street and Hyde Park Boulevard, according to a post published online May 31 by The Source, a blog about the LA Metro.
The rocky fragments were identified on May 24 by Gary Takeuchi, collections manager at the La Brea Tar Pits and Museum, as pieces of leg bones — one belonging to a sloth and the other to a bison, LA Metro representatives said in a statement.
Fossils of other ancient massive beasts, which roamed North America during the last ice age, have unexpectedly appeared during other LA construction projects in recent years. In April, work on a subway line extension near the La Brea Tar Pits was temporarily halted while paleontologists recovered first a camel bone and then a bone from an elephant relative, a mammoth or mastodon. And in December 2016, workers discovered a skull and partial tusks, as well as a section of mammoth tusk, also close by the tar pits.
In fact, fossils such as these turn up more frequently in LA than you might think, Takeuchi told Live Science in an email.
"Fossils periodically are found during excavation due to construction in the LA area. These fossils would probably not have been found if it were not for this construction unearthing them," he said.
The fossil belonging to the bison is part of a front leg, while the sloth fossil is a femur-head fragment, The Source reported. In photos that show the new finds positioned next to complete bones from the same animals, the rough and fragmented fossils don't look like much. But the trained eye of a paleontologist can quickly puzzle out the animal — and body part — that they represent, Takeuchi explained.
"The shape and size of the end of long bones can tell you what element in the body and what animal it belongs to," he said in an email. "You do not need the complete bone or animal for identification."
Artist's impression of haze on Earth during the Archean Eon.
We know little about Earth's surface temperatures for the first 4 billion years or so of its history. This presents a limitation into research of life's origins on Earth and how it might arise on distant worlds.
Now researchers suggest that by resurrecting ancient enzymes they could estimate the temperatures in which these organisms likely evolved billions of years ago. The scientists recently published their findings in the journal Proceedings of the National Academy of Sciences.
"We need a better understanding of not only how life first evolved on Earth, but how life and the Earth's environment co-evolved over billions of years of geological history," said lead author Amanda Garcia, a paleogeobiologist at the University of California, Los Angeles. "A similar co-evolution seems certain to be the case for any life elsewhere in the Universe."
Garcia and her colleagues focused on the history of Earth's surface temperatures. Rocks offer many clues to deduce temperatures over the last 550 million years in the Phanerozoic Era, when complex, multicellular life took off, including that of humans. However, few such "paleo-thermometers" exist for the earlier Precambrian Era, spanning the Earth's formation 4.6 billion years ago and the rise of life.
Earlier geological evidence has suggested that 3.5 billion years ago, during the Archean Eon, the oceans were 131 degrees to 185 degrees F (55 degrees to 85 degrees C). They cooled dramatically to current average temperatures of 59 degrees F (15 degrees C). Scientists made these estimates by examining oxygen and silicon isotopes in marine rocks. Quartz-rich rocks in the seabed, known as cherts, have higher levels of the heavier oxygen-18 and silicon-30 isotopes as the seawater gets colder. In principle, the ratio of heavier to lighter oxygen and silicon isotopes can shed light on ancient temperatures.
But such paleo-thermometers do not adequately take into account how these rocks or the ocean might have changed over the course of billions of years. Perhaps the isotopic ratios in seawater varied over time in response to physical or chemical alterations, such as water flows off the land or from hydrothermal vents.
The image on the left depicts what Earth
might have looked like more than 3 billion years ago in the early
Archean. The orange shapes represent the magnesium-rich proto-continents
before plate tectonics started, although it is impossible to determine
their precise shapes and locations. The ocean appears green due to a
high amount of iron ions in the water at that time. The timeline traces
the transition from a magnesium-rich upper continental crust to a
magnesium-poor upper continental crust.
Given the uncertainties, Garcia and her colleagues sought an independent measurement of seawater temperatures in the Precambrian that centers on the behavior of biological molecules. The scientists examined an enzyme known as nucleoside diphosphate kinase (NDK), which helps manipulate the building blocks of DNA and RNA, as well as many other roles. Versions of this protein are found in virtually all living organisms, and were likely vital to many extinct organisms as well. Previous research found a correlation between the optimal temperatures of protein stability and an organism's growth.
By comparing the molecular sequences of versions of NDK in a variety of contemporary species, researchers can reconstruct the versions of NDK that might have been present in their common ancestors. By synthesizing these reconstructions, scientists can experimentally test these "resurrected" ancient proteins to find the temperature that stabilizes the protein and deduce from that the likely temperature that supported the ancient organism.
Scientists estimate when ancient enzymes might have existed by looking at their closest living relatives of their host organism. The greater the number of differences in the genetic sequences of these relatives, the longer ago their last common relative likely lived. Scientists use these differences to gauge the age of biomolecules such as the reconstructions of NDK.
Previous research had reconstructed ancient enzymes to deduce past temperatures, but some of these enzymes may have come from organisms that lived in unusually hot environments, such as deep-sea hydrothermal vents, which would not be representative of the wider ocean. Instead, Garcia and her colleagues sought to reconstruct NDK from land plants and photosynthetic bacteria living in the upper sunlit depths of oceans, presumably far away from boiling hot springs.
Microbial reefs called stromatolites are examples of biological structures found as far back as 3.7 billion years ago.
Their research suggests that Earth's surface cooled from roughly 167 degrees F (75 degrees C) about 3 billion years ago to roughly 95 degrees (35 degrees F) about 420 million years ago. These findings are consistent with previous geological and enzyme-based results.
Garcia said such a dramatic cooling is hard to fathom, emphasizing how scientists need to remember how different conditions were in the past when figuring out how life evolved over time.
"It requires a lot of effort to envision a world that does not seem to fit with the common sense of our current Earth conditions."
A humpback whale breaching off the coast of Gabon.
As the United Nations Oceans Conference gets underway this week in New York City, there is a double dose of renewed hope concerning global efforts to mitigate the impacts of climate change.
First, an international team of researchers has determined that marine reserves help to lessen the gravity of five major environmental problems tied to climate change: ocean acidification, sea-level rise, increased intensity of storms, shifts in species distribution, and decreased productivity and oxygen availability. The research is published in the Proceedings of the National Academy of Sciences.
Second, President Ali Bongo Ondimba of Gabon announced today at the UN conference his country’s creation of a massive new network of marine protected areas consisting of 9 new marine parks and 11 new aquatic reserves. The network will be the largest of its kind in Africa and will expand Gabon’s protected waters to be over 20,463 square miles. The area includes both shallow coastal regions and abyssal 2.5-mile ocean depths.
Despite the impressive size of the protected areas, less than 5 percent of the planet’s oceans has been set aside for protection. Governments now have a new tool, however, for making sizable improvements to the environment.
Underwater surveys led by the Wildlife
Conservation Society, National Geographic, and Gabon’s Agence Nationale
de Parcs Nationaux (ANPN) uncovered a wealth of marine biodiversity
(such as this eel peering out from a enclosure of sea anemones),
providing valuable information for the formulation and creation of the
new marine protected area network.
Callum Roberts, a professor at the University of York’s environment department and lead author of the PNAS study, said governments can use marine preserves as a tool for meeting their commitments under the Paris Agreement on climate change, which recognized ocean ecosystems as a way to fight climate change.
“Government leaders can consider large, highly protected marine reserves as a feasible means to help their nations, and the world as a whole, to adapt and mitigate the impacts of climate change,” he said.
Roberts and his team evaluated existing peer-reviewed studies on the beneficial effects that existing marine reserves have had around the world. They determined that protecting key coastal systems — mangroves, salt marshes, and seagrasses — offers localized reductions in carbon dioxide concentrations and water acidity, as do protections of deep water fish. Such teleost, or bony, fish were found to excrete high magnesium calcite crystals that dissolve at shallow depths and raise ocean alkalinity, thereby likely helping to reduce ocean acidification.
Gabon’s marine protected area network will help protect pelagic fish populations such as these rainbow runners.
Co-author Bethan O’Leary, a research fellow at the University of York, added that she and her colleagues found that marine reserves create areas of great biological productivity, which may allow exploited fish and other marine life animal stocks, as well as degraded habitats, to recover.
“This occurs, in part, because the protection of coastal wetland nurseries facilitates completion of life cycles that require multiple habitats and enhance fisheries,” O’Leary said. “This even has an effect on stimulating primary productivity, and therefore CO2 removal, by boosting nutrient cycling.”
Matt Rand, who is the director of the Pew Bertarelli Ocean Legacy Project that supported part of the research, noted that a study published in March in the journal Nature found that the most effective marine reserves were those possessing the capacity for monitoring and enforcement.
“If there is strong local and community engagement, as well as engagement at the higher levels of government, there is a greater chance that a given reserve will be managed more effectivity,” Rand said.
Large, remote reserves pose the greatest challenges to monitoring. Satellites, drones, and other technologies, however, continue to make possible near-real time surveillance.
Rock Island, Palau.
The researchers mentioned three marine reserves that they say are highly-protected: the Northwestern Hawaiian Islands Marine National Monument (also known as the Papahānaumokuākea Marine National Monument), the Pitcairn Islands Marine Reserve, and the Palau Marine National Sanctuary.
The Hawaiian monument, designated under former President George W. Bush in 2006, was expanded by former President Barack Obama in 2016 to over 579,153 square miles. “It is home to more than 7000 species, a quarter of which are endemic, or found nowhere else on Earth,” Rand said. “The area provides habitat for rare species, such as threatened green turtles, endangered Hawaiian monk seals, and false killer whales, as well as 14 million seabirds representing 22 species.”
The Pitcairn reserve protects nearly 320,465 square miles in the remote waters surrounding the Pitcairn Islands in the South Pacific Ocean. This marine region is home to over 1,200 species — including rare ones, such as the many-spined butterfly fish — which are found nowhere else on the planet.
The Palau Marine National Sanctuary, designated in 2015, was highlighted by the researchers as being a highly-protected marine reserve. It covers 193,051 square miles, or more than 80 percent of the nation’s maritime territory.
“It is an area larger than California that is off limits to extractive activities, such as fishing, drilling, or mining,” Rand said. “The reserve was created to safeguard the future of the Palauan people, particularly as global change tightens its hold. It is exactly the kind of climate reserve that our study focuses on.”
A pair of bottlenose dolphins frolic in
the waters of Mayumba National Park, previously the country’s only
national park dedicated to the protection of marine species and one of
the locations of a recent coastal survey by WCS, National Geographic,
and Gabon’s Agence Nationale de Parcs Nationaux.
The just-announced network of marine protected areas in Gabon adds to this worldwide collection of water-based sanctuaries. In addition to the dedication of President Ali Bongo Ondimba, the project has involved the efforts of the Waitt Foundation, National Geographic Pristine Seas, Wildlife Conservation Society’s (WCS) Gabon Program and the Gabonese National Parks Agency. The Tiffany & Co. Foundation provided a $1 million grant towards the WCS Marine Protected Area (MPA) Fund, which has a mission of establishing and strengthening MPAs around the world.
Cristián Samper, president and CEO of the WCS, said creating marine protected areas will help advance the health of the world’s oceans.
“Gabon is showing great leadership with this massive expansion of efforts to protect its surrounding waters,” he said. “MPAs are an important conservation tool protecting habitat, improving fisheries, supporting livelihoods, and securing the long-term health of marine biodiversity and the oceans.”
Roberts, whose team was not involved in the Gabon work, is hopeful that the ambitious marine conservation plan for this African country will be properly enforced.
“Africa is an area that has taken the brunt of much of the planet’s hunger for seafood,” he said. “(The new marine protected areas network) is an interesting approach, and you want to believe that by implementing a network of protected areas, that Gabon will be able to enforce it effectively and the ecosystems will be able to recover. To make these areas properly effective, they will need high levels of protection from fishing and other sources of damage, as well as effective management, monitoring, and enforcement.”
A sheet of graphene is shown with an image of its structure in the background.
Graphene, the thinnest and strongest material on Earth, is just one atom thick yet 150 times stronger than the same weight of steel. A square meter of graphene is 1,000 times lighter than a piece of paper and more flexible than rubber. Graphene conducts electricity more than 200 times more efficiently than silicon and is made entirely of carbon, the fourth most-abundant element in the universe.
Since 2004, when researchers first isolated a single-atom-thick sheet of graphene from normal graphite — a feat that won them the Nobel Prize in physics in 2010 — some of the loftiest hopes of the technological world have been heaped on the shoulders of this “miracle material.”
Viewed at atomic scale, graphene is a two-dimensional matrix of carbon atoms arranged in hexagonal bonds like chicken wire. If you held a piece of graphene in your hand, it would be perfectly flat, 97-percent transparent and gossamer. But its unique physical properties make it one of the most hyped materials on the market.
Graphene, some predict, will usurp silicon as the backbone of our electronic circuits, enabling leaps in processing speeds well beyond Moore’s Law inside devices that are lighter, thinner, and more flexible. Others dream about graphene-boosted batteries that pack many times the energy density of today’s lithium-ion technology, greatly extending the range of electric vehicles and charging our phones and laptops in seconds.
In the near future, lightweight circuits printed with graphene ink might be embedded into product packaging, clothing, and even temporary tattoos right on your skin. These cheap and efficient wireless circuits will drive the Internet of Things, some acting as sensors (think of biosensors embedded into clothing to track your health) and others as “smart tags” that transmit useful product information to your phone.
Graphene’s lightweight strength will be used to create next-generation composites that will help us engineer lighter, faster, and safer vehicles and aircraft. The same composite materials and coatings will benefit from graphene’s exceptional electrical conductivity, turning a simple coat of paint into a heat sensor or wireless transmitter.
In fact, it’s hard to think of an industry or technology that wouldn’t potentially be transformed — or at least significantly impacted — if graphene lives up to the hype.
Andrea Ferrari is a nanotechnology professor at the University of Cambridge and director of the Cambridge Graphene Center, one of the leading academic research centers into the properties of and commercial applications for graphene. In an interview with Seeker, he said that “you can go on and on naming the possible applications for graphene.”
But it’s also hard to believe that any single material will really be as disruptive and game-changing as the graphene evangelists dream it will be. If the history of material science is any indication, graphene may very well trigger leaps in technological innovation — including entirely new products and unimagined applications — but we might have to wait a few years (or many years, in some cases) to see it happen.
So the question is: When will we actually see the miracles promised by the world’s most novel material?
Batch samples of graphene nano material in graphene processing factory.
If you’re looking to buy real-world products made with graphene, the list is still very short. You can buy graphene-reinforced tennis rackets, bicycle tires, and motorcycle helmets. But the small quantity of graphene in these products is designed to deliver more marketing buzz than a real technical advantage, said Jesus de la Fuente, founder and CEO of Graphenea, a company that manufactures and sells graphene to academic researchers and R&D departments.
De la Fuente told Seeker that the first widespread commercial applications for graphene will probably be in the field of biosensing. While not as sexy as flexible flat-screen TVs and smart tattoos, biosensors are critical components of medical diagnostics and the drug discovery process. Modern biosensors are built into chips that can detect the smallest presence of targeted molecules.
Graphene boasts several key properties that make it an ideal biosensor. The first is surface area. With a single-layer sheet of graphene — even on a tiny, micrometer-scale chip — every last carbon atom is exposed to the environment. And because graphene is highly conductive, you can run a current through it and measure the slightest changes in conductivity across the electric field.
The first wave of commercial graphene biosensing devices is already hitting the market. A company called Nanomedical Diagnostics sells a handheld device called the Agile R100 that’s based on “field effect biosensing” technology. Pharmaceutical companies in the early testing stages can quickly see whether a new drug is reaching its target, bypassing the slower and more expensive assay process.
Ferrari at the Cambridge Graphene Center is excited about the next wave of graphene-enabled biosensors. Since graphene is flexible, durable, and made entirely of carbon, it’s highly biocompatible, meaning it can be introduced into the body without deteriorating or triggering adverse reactions. Researchers are working on tiny graphene sensors that can be mounted on a tooth to monitor respiration or in the brain to predict seizures. Others are trying to make artificial graphene retinas for the vision-impaired.
“Since graphene is so thin, you can create very thin circuitry that can be implanted in the back of the eye to transmit information to the brain,” said Ferrari.
After biosensors, batteries are next in line for harnessing the unique properties of graphene. Both large global companies and small startups are racing to bring a graphene-boosted battery to market, said De la Fuente. That’s because lithium-ion (li-ion) batteries — the rechargeable batteries found in cell phones, laptops and electric cars — have reached a limit as to how much energy they can store and how quickly they can charge.
Since graphene is the world’s best electrical conductor, it holds the promise of doubling or even tripling the life of today’s li-ion batteries while shrinking charging times from hours to minutes. To achieve such a quantum leap in battery power, researchers are experimenting with battery electrodes made from pure graphene and graphene composites.
But biosensors and batteries are just the beginning when it comes to graphene’s transformative potential. De la Fuente says that 60,000 scientific papers are now published every year related to graphene.
“Graphene is just the tip of a massively huge iceberg that we just started to scratch from the top. We’re at the very beginning of a very long field of research and technology that will last for decades to come.”
MIT researchers made headlines recently when they showed off a futuristic construction material made from 3D-printed graphene that’s incredibly light — only 5 percent density — but 10 times stronger than steel. And researchers at the University of Manchester, where graphene was first produced in 2004, are testing a graphene oxide sieve that may provide a cheap and energy-efficient way of producing fresh drinking water from seawater.
So what’s standing in the way of our graphene-powered future? Price used to be a major obstacle. Back in 2006, when graphene production was in its infancy, the price for even a tiny piece of graphene was absurdly high. “We’re talking about trillions of dollars per gram,” Ferrari said.
Not anymore. De la Fuente told Seeker that the sales price of his graphene has dropped 27 percent per year since Graphenea opened in 2010. The price of single-layer sheet of graphene is now as low as 50 cents per square centimeter, the same as silicon, said De la Fuente.
And new, even cheaper methods of making graphene are showing up every day. The original technique was to exfoliate single layers from graphite. Next, researchers figured out how to “grow” layers of graphene in the lab using a method called chemical vapor deposition. Recently a team at Kansas State University stumbled on a new method that creates bucket loads of powdered graphene from igniting oxygen and hydrocarbon gas. Boom.
As graphene gets cheaper and more abundant, it’s worth asking, given all of its miraculous properties, will graphene eventually replace silicon as the foundation of our computers and electronic devices, ushering in a new era of crazy thin and fast machines? Not quite.
Graphene alone will never replace silicon for the simple fact that graphene isn’t a semiconductor. A sheet of pure graphene conducts electricity brilliantly, but it can’t shut off the flow of electrons. That’s the difference between a conductor and a semiconductor. For graphene to be used in processors, it will almost certainly need to be combined with other materials. This will diminish some of graphene’s superpowers, but perhaps still outperform the competition.
Ferrari at Cambridge said that there are around 2,000 other materials with the same, layered structure as graphite, the source of graphene. Now that researchers know how to separate graphite into single layers, they can employ the same technique to create all sorts of new monolayer materials, some of which are excellent semiconductors.
