четверг, 21 марта 2019 г.

Old Bones Causing an estimated 9.6 million deaths in 2018,…


Old Bones


Causing an estimated 9.6 million deaths in 2018, cancer is one of the most significant health concerns worldwide. While we generally focus on modern behaviours increasing the risk of cancer, such as smoking or exposure to pollutants, this disease has an ancient origin. Scientists recently discovered evidence of cancer in a 240-million-year-old fossil of an extinct relative of turtles, Pappochelys rosinae (pictured), making it the oldest known case in an amniote, the group of vertebrates including reptiles, birds and mammals. Pappochelys fossils helped palaeontologists shed light on how turtles evolved shells, but a suspicious growth on one specimen’s femur also caught their attention. Micro CT scans revealed a bone tumour closely resembling periosteal osteosarcoma, a bone cancer found in humans. While most tumours develop in soft tissues, so are not preserved in the fossil record, this discovery highlights the ancient nature of the genetic and cellular processes underpinning this disease.


Written by Emmanuelle Briolat



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Land-cover dynamics unveiled


ESA – Sentinel-2 Mission logo.


21 March 2019


Billions of image pixels recorded by the Copernicus Sentinel-2 mission have been used to generate a high-resolution map of land-cover dynamics across Earth’s landmasses. This map also depicts the month of the peak of vegetation and gives new insight into land productivity.



 Land-cover map

Using three years’ worth of optical data, the map can indicate the time of vegetation peak and variability of vegetation across seasons. Developed by GeoVille, an Austrian company specialised in the analysis of satellite data, this land-cover map dynamics map uses Copernicus Sentinel-2 archive data from 2015-18, and gives a complete picture of variations of vegetation. The map is displayed at a resolution of 20 m, however a 10 m version is available on request.


It can, for example, support experts working with land-cover classification and can serve as input for services in areas such as agriculture, forestry and land-degradation assessments.


“In particular, we use this as a basis to develop services for the agrofood industry and farmers growing potatoes and other crops, as well as information on how vegetation changes over the year,” explains Eva Haas, Head of GeoVille’s Agricultural Unit.



Swamps and lakes in West Africa

The land-cover dynamic layer was produced with GeoVille’s processing engine LandMonitoring.Earth, a fully-automated land-monitoring system built on data streams from the Copernicus Sentinel-1 and Sentinel-2 missions, as well as ESA third party missions such as the US Landsat.


“Using the system, we processed the complete Copernicus Sentinel-2 image archive along with artificial intelligence, machine learning and big data analytics,” explains Michael Riffler, Head of Research and Development at GeoVille.



Sentinel-2

“However, the key is the dense time-series of the Copernicus Sentinel-2 data which allows this information to be retrieved for the first time. To date, we have processed more than 23 billion pixels.”


The development has been done through ESA’s Earth observation innovation hub – ɸ-lab, and has been implemented by GeoVille and its subsidiary in the Netherlands – GEO4A.



Crops in the Netherlands

“This map forms an excellent foundation for other – more specialised – land cover classifications, whose development and deployment can be further accelerated by applying machine learning and AI,” says Iarla Kilbane-Dawe, the head of ESA’s Φ-Lab in Frascati, Italy.


The LandMonitoring.Earth system is designed to efficiently implement major client solutions such as the European Copernicus Land Monitoring Service products. Experts can specify desired land monitoring data for any place on the globe for any given time period, and receive a quality-controlled output, depending on the required geographic coverage and frequency.


The idea is to make information available to non-experts along with the specific resources and tools that they need.


Related links:


Sentinel-2: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus/Sentinel-2


Land Monitoring Earth Portal: https://landmonitoring.earth/portal/


GeoVille: http://www.geoville.com/


GEO4A: https://www.geo4a.com/


Images, Text, Credits: ESA/Contains modified Copernicus Sentinel data (2016–18), processed by GeoVille.


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2019 March 21 Star Trails and the Equinox Sunrise Image Credit…


2019 March 21


Star Trails and the Equinox Sunrise
Image Credit & Copyright: Juan Carlos Casado (TWAN, Earth and Stars)
Acknowledgement: Andrea Rodriguez Anton


Explanation: Stars trail and the Sun rises in this night and day composite panorama made on March 19. The view looks toward the eastern horizon from La Nava de Santiago, Spain. To create it, a continuous series of digital frames was recorded for about two hours and combined to trace the concentric motion of the stars through the night sky. A reflection of the Earth’s rotation, star trails curve around the north celestial pole toward upper left and the south celestial pole toward the lower right. Of course on that day the Sun was near the celestial equator, a diagonal straight line in the wide-angle projection. A dense dimming filter was used to capture the Sun’s image every two minutes. Superimposed on the star trails it rose due east in the morning sky. In the scene, foreground landscape and a local prehistoric monument were illuminated by full moonlight, though. The monument’s corridor faces nearly to the east and the equinox sunrise.


∞ Source: apod.nasa.gov/apod/ap190321.html


Over 5,000 artefacts uncovered at Mexico’s Tamaulipas archaeological site

Archaeologists continue to uncover artefacts and human remains at the Chak Pet archaeological site in Tamaulipas.











Over 5,000 artefacts uncovered at Mexico's Tamaulipas archaeological site
Archaeological dig in Tamaulipas [Credit: Milenio]

The National Institute of Anthropology and History (INAH) has found human remains, pottery, arrowheads and ritual figurines dating back nearly 3,000 years in the Huasteca region near the port of Altamira.
Scientists and students from the institute accompanied local officials this week on a tour of the newly uncovered vestiges of the old Huastecan civilization.











Over 5,000 artefacts uncovered at Mexico's Tamaulipas archaeological site
Archaeological dig in Tamaulipas [Credit: La Tarde]

So far, archaeologists have uncovered more than 5,000 artefacts and 532 human remains at 50 different points in the municipality of Altamira, presumably belonging to the former inhabitants of Chak Pet, who lived in the area from 900 BC to 200 AD.
The remains and artifacts will undergo radiocarbon tests to more precisely determine their age, along with other details such as diets and diseases they may have suffered.











Over 5,000 artefacts uncovered at Mexico's Tamaulipas archaeological site
Archaeological dig in Tamaulipas [Credit: La Tarde]

The newspaper Hoy Tamaulipas revealed the possibility of a future collaboration between the municipal government and INAH to create a tourist route to display the region’s rich cultural history as well as a museum to house the uncovered artifacts and serve as an aid to tourists and residents alike in learning about the region’s past and peoples.


Source: Mexico News Daily [March 15, 2019]



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Earth is a less volatile version of the Sun, study finds

ANU scientists have found that Earth is made of the same elements as the Sun but has less of the volatile elements such as hydrogen, helium, oxygen and nitrogen.











Earth is a less volatile version of the Sun, study finds
This image shows the bright light of a solar flare on the left side of the sun and an eruption of solar material shooting
through the sun’s atmosphere, called a prominence eruption [Credit: NASA/Goddard/SDO]

Lead author of the study, Dr Haiyang Wang, said they made the best estimate of the composition of Earth and the Sun with the aim of creating a new tool to measure the elemental composition of other stars and rocky planets that orbit them.


“The composition of a rocky planet is one of the most important missing pieces in our efforts to find out whether a planet is habitable or not,” said Dr Wang from the ANU Research School of Astronomy and Astrophysics (RSAA).


Other rocky planets in the Universe are devolatised pieces of their host stars, just like Earth.


Co-author and RSAA colleague Associate Professor Charley Lineweaver said every star had some kind of planetary system in orbit around it.


“The majority of stars probably have rocky planets in or near the habitable zone,” he said.


Co-author Professor Trevor Ireland, from the ANU Research School of Earth Sciences, said the team conducted the study by comparing the composition of Earth rocks with meteorites and the Sun’s outer shell.


“This comparison yields a wealth of information about the way the Earth formed. There is a remarkably linear volatility trend that can be used as a baseline to understand the relationships between meteorite, planet and stellar compositions,” he said.


The research will be published in the journal Icarus.


Source: Australian National University [March 16, 2019]



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Hepatitis B virus sheds light on ancient human population movements into Australia

Australian researchers have used current hepatitis B virus (HBV) genome sequences to deduce ancient human population movements into Australia, adding weight to the theory that the mainland Aboriginal population separated from other early humans at least 59 thousand years ago and possibly entered the country near the Tiwi Islands.











Hepatitis B virus sheds light on ancient human population movements into Australia
The initial migration route for HBV/C4 into the Tiwi Islands / East Arnhem (orange arrow)
[Credit: Dr Lillli Yuen/Doherty]

The discovery was made as an offshoot of the Characterising Hepatitis B in Indigenous Australians thRough Molecular epidemiology (CHARM) study, commenced in 2010 by the Menzies School of Health Research (Menzies). Chronic HBV infection is endemic in Australian Aboriginal and Torres Strait Islander people and is an important cause of morbidity and mortality due to liver disease and liver cancer.


As part of caring for patients with hepatitis B infections in the CHARM study, the research team collected HBV samples from people living in over 30 communities across the NT and found HBV isolated from Aboriginal Australians is a unique strain not found anywhere else in the world, known as HBV/C4.


In the same way that human genome sequences are used to trace ancient human migration, the researchers predicted they could use modern day viral genomes to infer the movement of the people that have carried these viruses over many generations.


Published in Molecular Biology and Evolution, the study used cutting-edge evolutionary analyses of the HBV DNA sequences together with archaeological fossil and human genome data.


The researchers found that the precursor of the modern HBV/C4 virus entered Australia over 51 thousand years ago, and then separated into two groups; one centred in the northwest region, and a second in the central/eastern region of the NT. Strikingly, the two groups share a similar geographical distribution to the two main divisions of Aboriginal Australian languages spoken in Australia today.











Hepatitis B virus sheds light on ancient human population movements into Australia
The team collected HBV samples from people living in over 30 communities across the Northern Territory
[Credit: Dr Jay Roberts]

Co-author on the paper, the Royal Melbourne Hospital’s Dr Margaret Littlejohn, who holds an honorary position with the University of Melbourne and is a Senior Medical Scientist in the Victorian Infectious Diseases Reference Laboratory at the Doherty Institute, said that the entry point and timing of ancient human migration into continental Sahul – the combined landmass of Australia, New Guinea and Tasmania – are subject to debate.


“As we were analysing the sequences of HBV isolated as part of this study, we noted that the virus sequences had very strong geographical connections to the communities we visited,” said Dr Littlejohn.


“This led us to postulate that we might be able to use this geographical relationship to find out the origin of HBV and how long it might have been in Australia. This is the first time viral genomes have been used in this way in Australia.”


Another co-author on the paper, Professor Josh Davis, Senior Principal Research Fellow at Menzies, said the discovery had generated great interest with Aboriginal research partners and patients.


“Most pleasingly, it has raised the profile of hepatitis B in communities. Community members have asked to find out more about hepatitis B and how they can be tested and treated,” said Professor Davis.











Hepatitis B virus sheds light on ancient human population movements into Australia
There’s a more than 60 per cent probability that the HBV/C4 virus entered through either
the Tiwi Islands or East Arnhem regions [Credit: WikiCommons]

“It’s really exciting to take a novel approach, and use viral genetics to help tell the story of Australia’s first people”.


The study was endorsed by an Indigenous Reference Group comprised of members representing six different remote communities from across the NT and established by the Menzies Hepatitis B Research Program. The researchers also ensured that results were fed back to the main communities where samples came from.


Senior Aboriginal Health Practitioner, Sarah Bukulatjpi, who is also a co-author on the paper, said: “I am really pleased that we are finding out more details about HBV found in Aboriginal people. This can only help to eliminate hep B for the future.


“It is good for us to learn about this and for us not to be silent or feel shame; the fact the virus is so old helps to add to the evidence that Aboriginal people have been in Australia for a long long time,” she concluded.


Source: The University of Melbourne [March 17, 2019]



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Watch the Skies: Happy Equinox!


Astronomy logo.


March 20, 2019


Happy equinox, Earthlings! March 20 marks the spring equinox, one of two seasonal markers in Earth’s year-long orbit when the Sun appears to shine directly over the equator, and daytime and nighttime are nearly equal lengths–12 hours–everywhere on the planet.



Image above: During the equinoxes, both hemispheres receive equal amounts of daylight. (Image not to scale.) Image Credits: NASA/GSFC/Genna Duberstein.


It’s the start of astronomical spring in the Northern Hemisphere, meaning more sunlight and longer days. From here until the beginning of fall, daytime will be longer than nighttime as the Sun travels a longer, higher arc across the sky each day, reaching a peak at the start of summer. It’s just the opposite in the Southern Hemisphere, where March 20 marks the fall equinox.


What’s more? The first full Moon of spring will rise tonight, lighting the skies on the equinox. Usually, a full Moon arrives a few days to weeks before or after the equinox. It’s close, but not a perfect match. Tonight’s full Moon, however, reaches maximum illumination less than four hours after the equinox. There hasn’t been a comparable coincidence since the spring equinox in 2000.



Image above: When the Moon, on its orbit around Earth, reaches the point farthest from the Sun, we see a full Moon. Image Credits: NASA/GSFC/Genna Duberstein.


And because the Moon is near perigee, it qualifies as a supermoon–the third and final of 2019. It’s not a big supermoon, so you won’t really be able to see the difference between this full Moon and any other one with your eyes. But keep an keep an eye on the Moon as it rises and creeps above the eastern skyline. A low-hanging Moon can appear strangely inflated. This is the Moon illusion at work.


Super or seemingly not, it’s a rare celestial coincidence to usher in springtime.


Watch the Skies: https://blogs.nasa.gov/Watch_the_Skies/


Images (mentioned), Text, Credits: NASA/Lee Mohon.


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The Rise and Fall of Ziggy Star Formation and the Rich Dust from Ancient Stars


ALMA and Hubble Space Telescope (HST) image of the distant galaxy MACS0416_Y1. Distribution of dust and oxygen gas traced by ALMA are shown in red and green, respectively, while the distribution of stars captured by HST is shown in blue. Credit: ALMA (ESO/NAOJ/NRAO), NASA/ESA Hubble Space Telescope, Tamura, et al.  Hi-res image




Artist’s impression of the distant galaxy MACS0416_Y1. Based on the observations with ALMA and HST, researchers assume that this galaxy contains stellar clusters with a mix of old and young stars. The clouds of gas and dust are illuminated by starlight. Credit: National Astronomical Observatory of Japan. Hi-res image


Researchers have detected a radio signal from abundant interstellar dust in MACS0416_Y1, a galaxy 13.2 billion light-years away in the constellation Eridanus. Standard models can’t explain this much dust in a galaxy this young, forcing us to rethink the history of star formation. Researchers now think MACS0416_Y1 experienced staggered star formation with two intense starburst periods 300 million and 600 million years after the Big Bang with a quiet phase in between. Hi-res image


Stars are the main players in the Universe, but they are supported by the unseen backstage stagehands: stardust and gas. Cosmic clouds of dust and gas are the sites of star formation and masterful storytellers of the cosmic history.


“Dust and relatively heavy elements such as oxygen are disseminated by the deaths of stars,” said Yoichi Tamura, an associate professor at Nagoya University and the lead author of the research paper, “Therefore, a detection of dust at some point in time indicates that a number of stars have already formed and died well before that point.”


Using ALMA (Atacama Large Millimeter/submillimeter Array), Tamura and his team observed the distant galaxy MACS0416_Y1. Because of the finite speed of light, the radio waves we observe from this galaxy today had to travel for 13.2 billion years to reach us. In other words, they provide an image of what the galaxy looked like 13.2 billion years ago, which is only 600 million years after the Big Bang.


The astronomers detected a weak but telltale signal of radio emissions from dust particles in MACS0416_Y1 [1]. The Hubble Space Telescope, the Spitzer Space Telescope, and the European Southern Observatory’s Very Large Telescope have observed the light from stars in the galaxy; and from its color they estimate the stellar age to be 4 million years.


“It ain’t easy,” said Tamura half-lost in a moonage daydream. “The dust is too abundant to have been formed in 4 million years. It is surprising, but we need to hang onto ourselves. Older stars might be hiding in the galaxy, or they may have died out and disappeared already.”


“There have been several ideas proposed to overcome this dust budget crisis,” said Ken Mawatari, a researcher at the University of Tokyo. “However, no one is conclusive. We made a new model which doesn’t need any extreme assumptions diverging far from our knowledge of the life of stars in today’s Universe. The model well explains both the color of the galaxy and the amount of dust.” In this model, the first burst of star formation started at 300 million years and lasted 100 million years. After that, the star formation activity went quiet for a  and then restarted at 600 million years. The researchers think ALMA observed this galaxy at the beginning of its second generation of star formation.


“Dust is a crucial material for planets like Earth,” explains Tamura. “Our result is an important step forward for understanding the early history of the Universe and the origin of dust.”




Notes


[1] ALMA marginally detected dust emissions in a galaxy A2744_YD1 with a similar age MACS0416_Y1. The detection of dust in the present research has a better signal-to-noise ratio.




Additional Information



These observation results were published as Tamura et al. “Detection of the Far-infrared [O III] and Dust Emission in a Galaxy at Redshift 8.312: Early Metal Enrichment in the Heart of the Reionization Era” in the Astrophysical Journal in March 2019.



The research team members are:



Yoichi Tamura (Nagoya University), Ken Mawatari (Osaka Sangyo University/The University of Tokyo), Takuya Hashimoto (Osaka Sangyo University/National Astronomical Observatory of Japan), Akio K. Inoue (Osaka Sangyo University), Erik Zackrisson (Uppsala University), Lise Christensen (University of Copenhagen), Christian Binggeli (University of Copenhagen), Yuichi Matsuda (National Astronomical Observatory of Japan/SOKENDAI), Hiroshi Matsuo (National Astronomical Observatory of Japan/SOKENDAI),Tsutomu T. Takeuchi (Nagoya University), Ryosuke S. Asano (Nagoya University), Kaho Sunaga (Nagoya University), Ikkoh Shimizu (Osaka University), Takashi Okamoto (Hokkaido University), Naoki Yoshida (The University of Tokyo), Minju Lee (Nagoya University/National Astronomical Observatory of Japan), Takatoshi Shibuya (Kitami Institute of Technology), Yoshiaki Taniguchi (The Open University of Japan), Hideki Umehata (The Open University of Japan/RIKEN/The University of Tokyo), Bunyo Hatsukade (The University of Tokyo), Kotaro Kohno (The University of Tokyo), and Kazuaki Ota (University of Cambridge/Kyoto University).



This research was supported by JSPS/MEXT KAKENHI (Nos. 17H06130, 17H04831, 17KK0098, 17H01110, 18H04333, and 17K14252) and the Swedish National Space Board.



The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).




ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.



Contacts


Nicolás Lira
Education and Public Outreach Coordinator
Joint ALMA Observatory, Santiago – Chile
Phone: +56 2 2467 6519
Cell phone: +56 9 9445 7726
Email: nicolas.lira@alma.cl


Masaaki Hiramatsu
Education and Public Outreach Officer, NAOJ Chile
Observatory
, Tokyo – Japan
Phone: +81 422 34 3630
Email: hiramatsu.masaaki@nao.ac.jp


Charles E. Blue
Public Information Officer
National Radio Astronomy Observatory Charlottesville, Virginia – USA
Phone: +1 434 296 0314
Cell phone: +1 202 236 6324
Email: cblue@nrao.edu


Calum Turner
ESO Assistant Public Information Officer 
Garching bei München, Germany
Phone: +49 89 3200 6670 
Email: calum.turner@eso.org






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Spiralling giants: Witnessing the birth of a massive binary star system

Scientists from the RIKEN Cluster for Pioneering Research in Japan, Chalmers University of Technology in Sweden and the University of Virginia in the USA and collaborators have made observations of a molecular cloud that is collapsing to form two massive protostars that will eventually become a binary star system.











Spiralling giants: Witnessing the birth of a massive binary star system
The background image shows dense, dusty streams of gas (shown in green) that appear to be flowing towards the center.
Gas motions, as traced by the methanol molecule, that are towards us are shown in blue; motions away from us in red.
The inset image shows a zoom-in view of the massive forming binary, with the brighter, primary protostar moving
 toward us shown in blue and the fainter, secondary protostar moving away from us shown in red. The blue and
 red dotted lines show an example of orbits of the primary and secondary spiraling around their center
of mass (marked by the cross) [Credit: RIKEN]

While it is known that most massive stars possess orbiting stellar companions it has been unclear how this comes about – for example, are the stars born together from a common spiraling gas disk at the center of a collapsing cloud, or do they pair up later by chance encounters in a crowded star cluster.


Understanding the dynamics of forming binaries has been difficult because the protostars in these systems are still enveloped in a thick cloud of gas and dust that prevents most light from escaping. Fortunately, it is possible to see them using radio waves, as long as they can be imaged with sufficiently high spatial resolution.


In the current research, published in Nature Astronomy, the researchers led by Yichen Zhang of the RIKEN Cluster for Pioneering Research and Jonathan C. Tan at Chalmers University and the University of Virginia, used the Atacama Large Millimeter/Submillimeter Array (ALMA) telescope array in northern Chile to observe, at high spatial resolution, a star-forming region known as IRAS07299-1651, which is located 1.68 kiloparsecs, or about 5,500 light years, away.


The observations showed that already at this early stage, the cloud contains two objects, a massive “primary” central star and another “secondary” forming star, also of high mass. For the first time, the research team were able to use these observations to deduce the dynamics of the system. The observations showed that the two forming stars are separated by a distance of about 180 astronomical units–a unit approximately the distance from the earth to the sun. Hence, they are quite far apart. They are currently orbiting each other with a period of at most 600 years, and have a total mass at least 18 times that of our sun.


According to Zhang, “This is an exciting finding because we have long been perplexed by the question of whether stars form into binaries during the initial collapse of the star-forming cloud or whether they are created during later stages. Our observations clearly show that the division into binary stars takes place early on, while they are still in their infancy.”


Another finding of the study was that the binary stars are being nurtured from a common disk fed by the collapsing cloud and favoring a scenario in which the secondary star of the binary formed as a result of fragmentation of the disk originally around the primary. This allows the initially smaller secondary protostar to “steal” infalling matter from its sibling and eventually they should emerge as quite similar “twins”.


Tan adds, “This is an important result for understanding the birth of massive stars. Such stars are important throughout the universe, not least for producing, at the ends of their lives, the heavy elements that make up our Earth and are in our bodies.”


Zhang concludes, “What is important now is to look at other examples to see whether this is a unique situation or something that is common for the birth of all massive stars.”


Source: RIKEN [March 18, 2019]




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How heavy elements come about in the universe

Heavy elements are produced during stellar explosion or on the surfaces of neutron stars through the capture of hydrogen nuclei (protons). This occurs at extremely high temperatures, but at relatively low energies. An international research team headed by Goethe University has now succeeded in investigating the capture of protons at the storage ring of the GSI Helmholtzzentrum für Schwerionenforschung.











How heavy elements come about in the universe
For the first time, the fusion of hydrogen and xenon was able to be investigated at the same
temperatures as occur in stellar explosions using an ion storage ring
[Credit: Mario Weigand, Goethe-Universität]

As the scientists report in the current issue of Physical Review Letters, their goal was to determine more precisely the probability for a proton capture in astrophysical scenarios. As Dr. Jan Glorius from the GSI atomic physics research department explains, they were faced with two challenges in this endeavour: “The reactions are most probable under astrophysical circumstances in an energy range called the Gamow window. In this range, nuclei tend to be somewhat slow, making them difficult to obtain in the required intensity. In addition, the cross section – the probability of proton capture – decreases rapidly with energy. Until now, it has been almost impossible to create the right conditions in a laboratory for these kinds of reactions.”
René Reifarth, Professor for experimental astrophysics at Goethe University suggested a solution as early as ten years ago: The low energies within the Gamow window range can be reached more precisely when the heavy reaction partner circulates in an accelerator in which it interact with an stationary proton gas. He achieved first successes in September 2015 with a group of Heimholtz early career researchers. Since then, his team has gained excellent support from Professor Yuri Litvinov, who leads the EU-funded research project ASTRUm at GSI.


In the experiment, the international team first produced xenon ions. They were decelerated in the experimental storage ring ESR and caused to interact with protons. This resulted in reactions in which the xenon nuclei captured a proton and were transformed into heavier caesium – a process like that which occurs in astrophysical scenarios.


“The experiment makes a decisive contribution to advancing our understanding of nucleosynthesis in the cosmos,” says René Reifarth. “Thanks to the high-performance accelerator facility at GSI, we were able to improve the experimental technique for decelerating the heavy reaction partner. We now have more exact knowledge of the area in which the reaction rates occur, which until now had only been theoretically predicted. This allows us to more precisely model the production of elements in the universe.”


Source: Goethe University Frankfurt [March 18, 2019]



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A prehistoric puzzle in the Kuiper Belt

The farthest object ever explored is slowly revealing its secrets, as scientists piece together the puzzles of Ultima Thule – the Kuiper Belt object NASA’s New Horizons spacecraft flew past on New Year’s Day, four billion miles from Earth.











A prehistoric puzzle in the Kuiper Belt
Artist’s impression of NASA’s New Horizons spacecraft flying past Ultima Thule, a Kuiper Belt object officially
named 2104 MU69 [Credit: NASA/Johns Hopkins University Applied Physics Laboratory/
Southwest Research Institute]

Analyzing the data New Horizons has been sending home since the flyby of Ultima Thule (officially named 2014 MU69), mission scientists are learning more about the development, geology and composition of this ancient relic of solar system formation. The team discussed those findings today at the 50th Lunar and Planetary Science Conference in The Woodlands, Texas.


Ultima Thule is the first unquestionably primordial contact binary ever explored. Approach pictures of Ultima Thule hinted at a strange, snowman-like shape for the binary, but further analysis of images, taken near closest approach – New Horizons came to within just 2,200 miles (3,500 kilometers) – have uncovered just how unusual the KBO’s shape really is. At 22 miles (35 kilometers) long, Ultima Thule consists of a large, flat lobe (nicknamed “Ultima”) connected to a smaller, rounder lobe (nicknamed “Thule”).


This strange shape is the biggest surprise, so far, of the flyby. “We’ve never seen anything like this anywhere in the solar system,” said New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute, Boulder, Colorado. “It is sending the planetary science community back to the drawing board to understand how planetesimals – the building blocks of the planets – form.”


Because it is so well preserved, Ultima Thule is offering our clearest look back to the era of planetesimal accretion and the earliest stages of planetary formation. Apparently Ultima Thule’s two lobes once orbited each other, like many so-called binary worlds in the Kuiper Belt, until something brought them together in a “gentle” merger.











A prehistoric puzzle in the Kuiper Belt
Ultima Thule [Credit: NASA/Johns Hopkins University Applied Physics Laboratory/
Southwest Research Institute]

“This fits with general ideas of the beginning of our solar system,” said William McKinnon, a New Horizons co-investigator from Washington University in St. Louis. “Much of the orbital momentum of the Ultima Thule binary must have been drained away for them to come together like this. But we don’t know yet what processes were most important in making that happen.”


That merger may have left its mark on the surface. The “neck” connecting Ultima and Thule is reworked, and could indicate shearing as the lobes combined, said Kirby Runyon, a New Horizons science team member from the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland.


Runyon and fellow team geologists are describing and trying to understand Ultima Thule’s many surface features, from bright spots and patches, to hills and troughs, to craters and pits. The craters, while at first glance look like impact craters, could have other origins. Some may be pit craters, where material drains into underground cracks, or a result of sublimation, where ice went directly from solid to gas and left pits in its place. The largest depression is a 5-mile-wide (8-kilometer-wide) feature the team has nicknamed Maryland crater. It could be an impact crater, or it could have formed in one of the other above-mentioned ways.


“We have our work cut out to understand Ultima Thule’s geology, that is for sure,” Runyon said.


In color and composition, New Horizons data revealed that Ultima Thule resembles many other objects found in its region of the Kuiper Belt. Consistent with pre-flyby observations from the Hubble Telescope, Ultima Thule is very red – redder even than Pluto, which New Horizons flew past on the inner edge of the Kuiper Belt in 2015 – and about the same color as many other so-called “cold classical” KBOs. (“Cold” referring not to temperature but to the circular, uninclined orbits of these objects; “classical” in that their orbits have changed little since forming, and represent a sample of the primordial Kuiper Belt.)



This short movie shows the view of Kuiper Belt object 2014 MU69 (nicknamed Ultima Thule) as seen by NASA’s New Horizons


 spacecraft from Dec. 7, 2018 to Jan. 1, 2019. During the approach, Ultima Thule transforms from a faint dot 20 million miles


 (31 million kilometers) away, indistinguishable from thousands of background stars, to a newly revealed world unlike any 


seen before, from a range of 5,000 miles (8,000 kilometers). The sequence consists of actual New Horizons images, taken


 at discrete intervals during the approach, supplemented with computer-generated intermediate frames in order to make 


a smooth movie. Time slows down during the movie to show clearly both the slow initial phases of the approach and the 


very rapid final stages. The final image (seen behind the credits) is a parting crescent view of Ultima Thule, taken 


10 minutes after closest approach occurred at 12:33 a.m. EST on Jan. 1 [Credit: NASA/Johns Hopkins University 


Applied Physics Laboratory/Southwest Research Institute/National Optical Astronomy Observatory/


Brian May/Maria Banks/Roman Tkachenko]


“This is the first time one of these ‘ultra red’ objects has been explored, and our observations open all kinds of new questions,” said Carly Howett, a New Horizons science team member from SwRI. “The color imaging even reveals subtle differences in coloration across the surface, and we really want to know why.”


New Horizons scientists have also seen evidence for methanol, water ice and organic molecules on the surface. “The spectrum of Ultima Thule is similar to some of the most extreme objects we’ve seen in the outer solar system,” said Silvia Protopapa, a New Horizons co-investigator from SwRI. “So New Horizons is giving us an incredible opportunity to study one of these bodies up close.”


The Ultima Thule data transmission continues, though all of the data from the flyby won’t be on the ground until late summer 2020. In the meantime, New Horizons continues to carry out distant observations of additional Kuiper Belt objects and mapping the charged-particle radiation and dust environment in the Kuiper Belt.


The New Horizons spacecraft is 4.1 billion miles (6.6 billion kilometers) from Earth, operating normally and speeding deeper into the Kuiper Belt at nearly 33,000 miles (53,000 kilometers) per hour.


Source: NASA [March 18, 2019]




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Nile shipwreck vindicates Herodotus after 2,500 years

Archaeologists have recently discovered an ancient shipwreck which proves the Greek Historian Herodotus was accurate in his description, almost 25 centuries ago, regarding the construction of a Nile river boat called a ‘baris’ .











Nile shipwreck vindicates Herodotus after 2,500 years
An archaeologist inspects the keel of a shipwreck discovered in the waters around the sunken port-city
of Thonis-Heracleion [Credit: Christoph Gerigk/Franck Goddio/Hilti Foundation]

The shipwreck, discovered recently off the Mediterranean coast of Egypt near the ancient, and now sunken, city of Thonis-Heracleion was of a vessel called a ”baris.


This exact type of ship was described in great detail by Herodotus in his book Historia following a visit he made to the port city of Thonis-Heracleion in Egypt.


Herodotus was impressed by the way people were constructing the ship, which was used to sail across the Nile River.


For centuries, scholars and archaeologists believed that the type of ship Herodotus described never actually existed, because such ships had never once been found by anyone on the planet.











Nile shipwreck vindicates Herodotus after 2,500 years
The wooden hull of ship 17 [Credit: Christoph Gerigk/Franck Goddio/Hilti Foundation]

This theory was recently blown up when a group of archaeologists discovered a well-preserved shipwreck off the coast of Egypt in the Canopic Mouth of the Nile, in the Mediterranean Sea. What the archaeologists saw witnessed when they dove into the waters was exactly the kind of vessel Herodotus had perfectly described in his book exactly 2,469 years ago.
The 28-metre long vessel was one of the first ships used by the Egyptians to trade during ancient times. The vessels Herodotus described in his book must have been the exact same type of ship, but were only slightly smaller.


Dr. Damian Robinson, the director of Oxford University’s center for maritime archaeology, points out that ”where planks are joined together to form the hull, they are usually joined by mortise and tenon joints which fasten one plank to the next.











Nile shipwreck vindicates Herodotus after 2,500 years
An artistic rendition of the discovered shipwreck. The upper half of the model illustrates the wreck
as excavated. Below this, unexcavated areas are mirrored to pro­duce a complete vessel outline
[Credit: Christoph Gerigk/Franck Goddio/Hilti Foundation]

“Here we have a completely unique form of construction, which is not seen anywhere else”, Robinson remarked in an interview with Britain’s The Guardian newspaper.
Most likely, this unique construction was the reason why Herodotus was so amazed when he saw this type of ship. The eminent historian was also astonished by the peculiar types of wood they were using to construct the ships, which to him was completely unknown.


Archaeologists believe that what Herodotus saw could have even been constructed in the very same shipyard as the vessel they discovered, as a word-by-word analysis of Herodotus’ text exactly matches the appearance of the ship.











Nile shipwreck vindicates Herodotus after 2,500 years
Bust of Herodotus of Halicarnassus (c484-425 BC)
[Credit: G Nimatallah/De Agostini/Getty Images]

Herodotus was a Greek historian who was the first writer to have treated historical subjects using a method of systematic investigation, leading him to be universally regarded as ”the Father of History.”


Belov’s exploration of the ship’s construction has been published in a monograph by the Oxford Centre for Maritime Archaeology, Ship 17: a baris from Thonis-Heracleion.


Source: Tornos News [March 18, 2019]



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Ancient Greek architectural piece put up for sale on Turkish website

An ancient Greek architectural piece has been put up for sale for 150 Turkish Liras (about $28) on an online platform selling second-hand items in the southern Turkish province of Antalya.











Ancient Greek architectural piece put up for sale on Turkish website
Credit: Hurriyet Daily News

The piece is on the website labelled as “black and white wooden chest” regardless of the Greek texts on it.


“The Culture and Tourism Ministry should do what is necessary immediately and prevent the sale. There are legal loopholes in treasure hunting and people are spoilt by this,” said Soner Ateşoğulları, the head of the Turkish Archaeologists Association.


“Treasure hunting should be thwarted. Laws should be regulated and penalties for this should increase. We are for a mechanism that detects and follows illegal excavations,” he said.











Ancient Greek architectural piece put up for sale on Turkish website
Credit: Hurriyet Daily News

Ateşoğulları added that museums attempt to detect and monitor illegal excavations but there is a lack of personnel.


“Recently we are seeing that [treasure hunting] has become much popular and we feel uneasy as the association. The media, as well, should not encourage treasure hunting,” he stressed.


Source: Hurriyet Daily News [March 18, 2019]



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Research predicts what makes evolution go backwards

The study of evolution is revealing new complexities, showing how the traits most beneficial to the fitness of individual plants and animals are not always the ones we see in nature.











Research predicts what makes evolution go backwards
Credit: Diàna Markosian

Instead, new research by McMaster behavioural scientists shows that in certain cases evolution works in the opposite direction, reversing individual improvements to benefit related members of the same group.


The research appears in the Journal of Evolutionary Biology, where lead author David Fisher shows that the increased evolution of selfless traits – such as sharing food and keeping watch for one another – is mathematically equivalent to the decreased evolution of individually beneficial traits.


“They’re two sides of the same coin,” Fisher explains. “On one side, traits evolve that benefit your kin, but don’t benefit you, because you’re helping your siblings or cousins. On the other side, traits that benefit you but cost your neighbours don’t evolve, because you’re causing damage to related individuals.”


The work is part of the ongoing effort to understand the paradox of altruistic behaviour in the wild, explains Fisher, a research fellow in McMaster’s Department of Psychology, Neuroscience and Behaviour.


Fisher goes on to show that another way evolution can go backwards is through the evolution of an individual’s negative effects on neighbours and group members. For example, a fast-growing tree may take all the sunlight, water and nutrients out of the environment, causing its neighbours to grow slowly. In the next generation, more trees are fast-growing but are also nasty neighbours. As a result, negative social effects are much more prevalent, and so everyone’s growth is reduced.


“That means evolution has gone backwards. Even though growing quickly is beneficial, because of these negative social effects, the population, on average, grows more slowly,” he says.


Fisher plans to travel to Ecuador this summer to study co-operative spiders, and whether changes in individual and group benefits can explain why co-operation diminishes at higher elevations.


Source: McMaster University [March 19, 2019]




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Caption Spotlight (20 March 2019): In the Gullies and Bedrock of…



Caption Spotlight (20 March 2019): In the Gullies and Bedrock of Ius Chasma 


This image was acquired in Ius Chasma, a major section of the western portion of the giant Valles Marineris trough.


We see a portion of a steep slope with gullies extending downhill (towards bottom of image). Many of the gully floors are dark, and in some places that dark material extends onto the fan-shaped deposits of the gullies. These dark features are candidates for recurring slope lineae (RSL), which are seasonal features that grow incrementally. The relation between RSL and gullies is not clear: does the RSL activity carve the gullies, or do they simply follow the gully topography created by other processes?  


Another closeup from this observation shows part of the floor of Ius Chasma, with layered bedrock draped by dunes.


NASA/JPL/University of Arizona


Giant ‘chimneys’ vent X-rays from Milky Way’s core


ESA – XMM-Newton Mission patch.


20 March 2019


By surveying the centre of our Galaxy, ESA’s XMM-Newton has discovered two colossal ‘chimneys’ funneling material from the vicinity of the Milky Way’s supermassive black hole into two huge cosmic bubbles.


The giant bubbles were discovered in 2010 by NASA’s Fermi Gamma-ray Space Telescope: one stretches above the plane of the Milky Way galaxy and the other below, forming a shape akin to a colossal hourglass that spans about 50 000 light years – around half the diameter of the entire Galaxy. They can be thought of as giant ‘burps’ of material from the central regions of our Milky Way, where its central black hole, known as Sagittarius A*, resides.



Galactic chimneys and bubbles

Now, XMM-Newton has discovered two channels of hot, X-ray emitting material streaming outwards from Sagittarius A*, finally linking the immediate surroundings of the black hole and the bubbles together.


“We know that outflows and winds of material and energy emanating from a galaxy are crucial in sculpting and altering that galaxy’s shape over time – they are key players in how galaxies and other structures form and evolve throughout the cosmos,” says lead author Gabriele Ponti of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, and the National Institute for Astrophysics in Italy.


“Luckily, our Galaxy gives us a nearby laboratory to explore this in detail, and probe how material flows out into the space around us. We used data gathered by XMM-Newton between 2016 and 2018 to form the most extensive X-ray map ever made of the Milky Way’s core.”


This map revealed long channels of super-heated gas, each extending for hundreds of light years, streaming above and below the plane of the Milky Way.


Scientists think that these act as a set of exhaust pipes through which energy and mass are transported from our Galaxy’s heart out to the base of the bubbles, replenishing them with new material.


This finding clarifies how the activity occurring at the core of our home Galaxy, both present and past, is connected to the existence of larger structures around it.



XMM-Newton view

The outflow might be a remnant from our Galaxy’s past, from a period when activity was far more prevalent and powerful, or it may prove that even ‘quiescent’ galaxies – those that host a relatively quiet supermassive black hole and moderate levels of star formation like the Milky Way – can boast huge, energetic outflows of material.


“The Milky Way is seen as a kind of prototype for a standard spiral galaxy,” says co-author Mark Morris of the University of California, Los Angeles, USA.


“In a sense, this finding sheds light on how all typical spiral galaxies – and their contents – may behave across the cosmos.”



Outflows from the core of the Galaxy

Despite its categorisation as quiescent on the cosmic scale of galactic activity, previous data from XMM-Newton have revealed that our Galaxy’s core is still quite tumultuous and chaotic. Dying stars explode violently, throwing their material out into space; binary stars whirl around one another; and Sagittarius A*, a black hole as massive as four million Suns, lies in wait for incoming material to devour, later belching out radiation and energetic particles as it does so.


Cosmic behemoths such as Sagittarius A* – and those even more massive – hosted by galaxies across the cosmos will be explored in depth by upcoming X-ray observatories like ESA’s Athena, the Advanced Telescope for High-Energy Astrophysics, scheduled for launch in 2031. Another future ESA mission, Lisa, the Laser Interferometer Space Antenna, will search for gravitational waves released by the merger of supermassive black holes at the core of distant, merging galaxies.


Meanwhile, scientists are busy investigating these black holes with current missions like XMM-Newton.


“There’s still a great deal to be done with XMM-Newton – the telescope could scan a significantly larger region of the Milky Way’s core, which would help us to map the bubbles and hot gas surrounding our Galaxy as well as their connections to the other components of the Milky Way, and hopefully figure out how all of this is linked together,” adds Gabriele.


“Of course, we’re also looking forward to Athena and the breakthrough it will enable.”



XMM-Newton

Athena will combine extremely high-resolution X-ray spectroscopy with excellent imaging capabilities over wide areas of the sky, allowing scientists to probe the nature and movement of hot cosmic gas like never before.


“This outstanding result from XMM-Newton gives us an unprecedented view of what’s really happening at the core of the Milky Way, and presents the most extensive X-ray map ever created of the entire central region,” says ESA XMM-Newton Project Scientist Norbert Schartel.


“This is especially exciting in the context of our upcoming missions. XMM-Newton is paving the way for the future generation of X-ray observatories, opening up abundant opportunities for these powerful spacecraft to make substantial new discoveries about our Universe.”


Notes for editors:


“An X-ray Chimney extending hundreds of parsecs above and below the Galactic Centre” by G. Ponti et al. is published in the journal Nature: https://www.nature.com/articles/s41586-019-1009-6


XMM-Newton data were used in conjunction with archival data from NASA’s Chandra X-Ray Observatory.


The bubbles stretching above and below the Milky Way’s disc are known as Fermi bubbles, and were discovered in gamma-ray data gathered by NASA’s Fermi Gamma-ray Space Telescope in 2010.


Related links:


XMM-Newton: http://sci.esa.int/xmm-newton/


NASA’s Chandra X-Ray Observatory: http://chandra.si.edu/


NASA’s Fermi Gamma-ray Space Telescope: https://www.nasa.gov/content/fermi-gamma-ray-space-telescope


Images, Text, Credits: ESA/Markus Bauer/Norbert Schartel/University of California/Mark Morris/Max Planck Institute for Extraterrestrial Physics/INAF Brera Astronomical Observatory/Gabriele Ponti/XMM-Newton/G. Ponti et al. 2019; ESA/C. Carreau/Gaia/DPAC (Milky Way map), CC BY-SA 3.0 IGO/Nature.


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Astronauts Gear Up for Spacewalk and Get Up to Date on Station Safety


ISS – Expedition 59 Mission patch.


March 20, 2019


The Expedition 59 crew is busy preparing for the first spacewalk of 2019 set to begin in just two days. Meanwhile, the orbital residents are still exploring the effects of space on their bodies while familiarizing themselves with emergency hardware.


NASA astronauts Nick Hague and Anne McClain continued organizing their tools this morning ahead of Friday morning’s spacewalk. The duo will enter the Quest module’s crew airlock and their spacesuits will go on battery power Friday around 8:05 a.m. EDT signaling the beginning of the spacewalk.



Expedition 59 EVA 52 & 53 Briefing March 19, 2019

Video above:: NASA experts discuss the upcoming power upgrade spacewalks. Video Credit: NASA.


Hague and McClain will spend about six-and-a-half hours upgrading the International Space Station’s storage capacity. They will swap out old nickel-hydrogen batteries with new lithium-ion batteries and install battery adapter plates on the Port-4 truss structure. NASA TV begins its live space coverage Friday at 6:30 a.m.



Image above: NASA astronaut and Expedition 59 Flight Engineer Christina Koch familiarizes herself with International Space Station hardware inside the Unity module. Image Credits: NASA/JSC.


Hague started Wednesday, however, in the Columbus lab module helping scientists understand how microgravity impacts the perception of time. McClain collected light measurements in the afternoon from two laboratory modules and the Quest airlock to document how new station LED lights affect crew wellness.


The station’s latest crew arrivals spent a couple of hours Wednesday morning checking out safety and communications gear. Hague along with Flight Engineers Christina Koch and Alexey Ovchinin split their time between the station’s U.S. and Russian segments looking at emergency hardware and procedures.



Image above: A waxing gibbous Moon is seen above Earth’s limb as the International Space Station was orbiting 266 miles above the South Atlantic Ocean. The term “supermoon” was coined in 1979 and is used to describe what astronomers would call a perigean (pear-ih-jee-un) full moon: a full Moon occurring near or at the time when the Moon is at its closest point in its orbit around Earth. Tonight’s supermoon is the third and final supermoon of 2019. The first was on Jan. 21, and the second was on Feb. 19. In this image, the Moon is waxing or growing bigger. Gibbous means that it is less than a full Moon, but larger than the Moon’s shape in its third quarter. Image Credit: NASA.


Related links:


Expedition 59: https://www.nasa.gov/mission_pages/station/expeditions/expedition59/index.html


Spacewalk: https://www.nasa.gov/mission_pages/station/spacewalks/


Quest module: https://www.nasa.gov/mission_pages/station/structure/elements/joint-quest-airlock


Port-4 truss structure: https://www.nasa.gov/mission_pages/station/structure/elements/truss-structure


NASA TV: https://www.nasa.gov/nasatv


Columbus lab module: https://www.nasa.gov/mission_pages/station/structure/elements/europe-columbus-laboratory


Perception of time: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7504


Light measurements: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=2013


Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html


International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html


Images (mentioned), Video (mentioned), Text, Credits: NASA/Mark Garcia/Yvette Smith.


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Study finds natural selection favours cheaters

Mutualisms, which are interactions between members of different species that benefit both parties, are found everywhere — from exchanges between pollinators and the plants they pollinate, to symbiotic interactions between us and our beneficial microbes.











Study finds natural selection favours cheaters
Acmispon strigosus is an annual herb that is native to California
[Credit: Sachs lab, UC Riverside]

Natural selection — the process whereby organisms better adapted to their environment tend to survive and produce more offspring — predicts, however, that mutualisms should fall apart. Individuals that gain from the cooperation of others but do not reciprocate (so-called cheaters) should arise and destabilize mutualisms. Yet to date, surprisingly little evidence of such cheating or destabilization exists.


A team of biologists at the University of California, Riverside, has now found strong evidence of this cheating.  Focusing on the interaction between nitrogen-fixing bacteria, or rhizobia, and their legume hosts spanning about 530 miles of California habitat, the researchers found that natural selection in their study populations favors cheating rhizobia.


The study, appearing in Ecology Letters, is the first to uncover cheater strains in natural populations and show how natural selection favors them.


The researchers used a previously published database to quantify the landscape abundance of different rhizobial strains. They focused on naturally occurring populations of rhizobia in the genus Bradyrhizobium and the native annual plants, Acmispon strigosus, that these bacteria inhabit. Within these datasets they found that the fewer benefits the rhizobia provide to their host plants, the more common the rhizobia are.


“Our data show that natural selection favors cheating rhizobia, and support predictions that rhizobia can often subvert plant defenses and evolve to exploit hosts,” said Joel Sachs, a professor of biology in the Department of Evolution, Ecology & Organismal Biology, who led the research team.


Sachs explained that beneficial bacteria are increasingly appreciated to be key for human health as well as the productivity of crops and livestock. Little is understood, however, about how much these bacterial services vary in natural systems and the forces that modulate them.


“In crop plants, in particular, agronomists have attempted — and failed — for several decades to design crop biofertilizers based on beneficial bacteria,” he said. “Similar challenges have been faced in applying bacteria in other host systems — probiotics, for example, which rarely affect host microbes. Our dataset suggests a potential flaw in these approaches; the bacteria, with their own evolutionary interests, can destabilize these interactions.”


In their paper, the researchers show how benefits of bacterial symbionts vary over space and time, and how rapidly these systems can evolve.


“We often view the services of bacteria as fixed, but this is not at all true,” Sachs said. “Just as each human varies a great deal in almost any trait we can measure, bacterial populations are even more highly variable. Understanding this variation and its drivers will be key to usefully harnessing these bacteria for our own purposes.”


Already, his team is actively working to better understand how beneficial bacteria can be applied to improve plant growth. Preliminary data show that it is crucial to carefully select among bacterial variants to avoid using harmful strains.


“Simply applying beneficial bacteria to a crop is often not going to be sufficient since exploitative strains are expected to be lurking within these populations,” Sachs said.


Source: University of California – Riverside [March 19, 2019]



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