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  • richardmitnick 1:39 pm on September 26, 2019 Permalink | Reply
    Tags: Clues for search for life on Mars, Drilling deep; looking closely, Paleobiology, the ancient Dresser Formation in the Pilbara region of Western Australia, , Western Australia’s famous 3.5-billion-year-old stromatolites   

    From University of New South Wales: “Earliest signs of life: scientists find microbial remains in ancient rocks” 

    U NSW bloc

    26 Sep 2019
    Isabelle Dubach

    Western Australia’s famous 3.5-billion-year-old stromatolites contain microbial remains of some of the earliest life on Earth, UNSW scientists have found.

    2
    Photomicrograph of pyritized stromatolites from the 3.5 billion-year-old Dresser Formation. The stromatolites are delineated by pyrite, also known as fool’s gold.

    Scientists have found exceptionally preserved microbial remains in some of Earth’s oldest rocks in Western Australia – a major advance in the field, offering clues for how life on Earth originated.

    The UNSW researchers found the organic matter in stromatolites – fossilised microbial structures – from the ancient Dresser Formation in the Pilbara region of Western Australia.

    The stromatolites have been thought to be of biogenic origin ever since they were discovered in the 1980s. However, despite strong textural evidence, that theory was unproven for nearly four decades, because scientists hadn’t been able to show the definitive presence of preserved organic matter remains – until today’s publication in prestigious journal Geology.

    “This is an exciting discovery – for the first time, we’re able to show the world that these stromatolites are definitive evidence for the earliest life on Earth,” says lead researcher Dr Raphael Baumgartner, a research associate of the Australian Centre for Astrobiology in Professor Martin Van Kranendonk’s team at UNSW.

    Professor Van Kranendonk says the discovery is the closest the team have come to a “smoking gun” to prove the existence of such ancient life.

    “This represents a major advance in our knowledge of these rocks, in the science of early life investigations generally, and – more specifically – in the search for life on Mars. We now have a new target and new methodology to search for ancient life traces,” Professor Van Kranendonk says.

    Drilling deep, looking closely

    Ever since the Dresser Formation was discovered in the 1980, scientists have wondered whether the structures were truly microbial and therefore the earliest signs of life.

    “Unfortunately, there is a climate of mistrust of textural biosignatures in the research community. Hence, the origin of the stromatolites in the Dresser Formation has been a hotly debated topic,” Dr Baumgartner says.

    “In this study, I spent a lot of time in the lab, using micro-analytical techniques to look very closely at the rock samples, to prove our theory once and for all.”

    Stromatolites in the Dresser Formation are usually sourced from the rock surface, and are therefore highly weathered. For this study, the scientists worked with samples that were taken from further down into the rock, below the weathering profile, where the stromatolites are exceptionally well preserved.

    “Looking at drill core samples allowed us to look at a perfect snapshot of ancient microbial life,” Dr Baumgartner says.

    Using a variety of cutting-edge micro-analytical tools and techniques – including high-powered electron microscopy, spectroscopy and isotope analysis – Dr Baumgartner analysed the rocks.

    He found that the stromatolites are essentially composed of pyrite – a mineral also known as ‘fool’s gold’ – that contains organic matter.

    “The organic matter that we found preserved within pyrite of the stromatolites is exciting – we’re looking at exceptionally preserved coherent filaments and strands that are typically remains of microbial biofilms,” Dr Baumgartner says.

    The researchers say that such remains have never been observed before in the Dresser Formation, and that actually seeing the evidence down the microscope was incredibly exciting.

    “I was pretty surprised – we never expected to find this level of evidence before I started this project. I remember the night at the electron microscope where I finally figured out that I was looking at biofilm remains. I think it was around 11pm when I had this ‘eureka’ moment, and I stayed until three or four o’clock in the morning, just imaging and imaging because I was so excited. I totally lost track of time,” Dr Baumgartner says.

    Clues for search for life on Mars

    Just over two years ago, Dr Baumgartner’s colleague Tara Djokic, a UNSW PhD candidate, found stromatolites in hot spring deposits in the same region in WA, pushing back the earliest known existence of microbial life on land by 580 million years.

    “Tara’s main findings were these exceptional geyserite deposits that indicate that there have been geysers in this area, and therefore fluid expulsions on exposed land surface,” Dr Baumgartner says.

    “Her study was focused on the broader geological setting of the paleo-environment – lending support to the theory that life originated on land, rather than in the ocean – whereas my study really went deeper on the finer details of the stromatolite structures from the area.”

    The scientists say that both studies are helping us answer a central question: where did humanity come from?

    “Understanding where life could have emerged is really important in order to understand our ancestry. And from there, it could help us understand where else life could have occurred – for example, where it was kick-started on other planets,” Dr Baumgartner says.

    Just last month, NASA and European Space Agency (ESA) scientists spent as week in the Pilbara with Martin Van Kranendonk for specialist training in identifying signs of life in these same ancient rocks. It was the first time that Van Kranendonk shared the region’s insights with a dedicated team of Mars specialists – a group including the Heads of NASA and ESA Mars 2020 missions.

    “It is deeply satisfying that Australia’s ancient rocks and our scientific know-how is making such a significant contribution to our search for extra-terrestrial life and unlocking the secrets of Mars,” says Professor Van Kranendonk.

    See the full article here .


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    U NSW Campus

    Welcome to UNSW Australia (The University of New South Wales), one of Australia’s leading research and teaching universities. At UNSW, we take pride in the broad range and high quality of our teaching programs. Our teaching gains strength and currency from our research activities, strong industry links and our international nature; UNSW has a strong regional and global engagement.

    In developing new ideas and promoting lasting knowledge we are creating an academic environment where outstanding students and scholars from around the world can be inspired to excel in their programs of study and research. Partnerships with both local and global communities allow UNSW to share knowledge, debate and research outcomes. UNSW’s public events include concert performances, open days and public forums on issues such as the environment, healthcare and global politics. We encourage you to explore the UNSW website so you can find out more about what we do.

     
  • richardmitnick 7:57 am on March 22, 2019 Permalink | Reply
    Tags: Burgess Shale in Canada, Cambrian explosion of life, Paleoarchaeology, Paleobiology, , Qingjiang and Chengjiang fossils in China,   

    From Science News: “Newfound fossils in China highlight a dizzying diversity of Cambrian life” 

    From Science News

    March 21, 2019
    Carolyn Gramling

    1
    ANCIENT IMPRINTS The newly described Qingjiang biota, a rich fossil site dating to about 518 million years ago, helps document a rapid flourishing of diverse invertebrate life known as the Cambrian explosion. The fossils include abundant jellyfish (left) and comb jellies (middle), as well as a segmented, spiny animal that may be a kinorhynch (right).

    Along the banks of China’s Danshui River lies a treasure trove of fossils that may rival the most famous Cambrian fossil assemblage of all, Canada’s Burgess Shale. The roughly 518-million-year-old site contains a dizzying abundance of beautifully preserved weird and wonderful life-forms, from jellyfish and comb jellies to arthropods and algae.

    So far, researchers led by paleontologist Dongjing Fu of Northwest University in Xian, China, have collected 4,351 specimens at the new site, representing 101 different taxa, or groups of organisms. Of those taxa, about 53 percent have never before been observed, Fu and her colleagues report in the March 22 Science — not even at other well-known Cambrian fossil sites such as the 508-million-year-old Burgess Shale or a 518-million-year-old site known as Chengjiang, also in China.

    “It’s an exciting discovery,” says Jean-Bernard Caron, a paleontologist at the Royal Ontario Museum in Toronto who wasn’t involved in the study. During the Cambrian Period, which began about 542 million years ago, life diversified extremely rapidly. So many new forms appeared in such a relatively short period of time that this diversification is known as the Cambrian explosion. The find “shows that there’s hope for new discoveries” of other Cambrian fossil sites, he says.

    2
    FOSSIL FINDS Researchers discovered the Qingjiang fossils along the bank of China’s Danshui River in Hubei Province. Dong King Fu

    Such sites represent snapshots of life long ago, and no one site can portray the true diversity of life on Earth at any given time, Caron says. “It’s a giant jigsaw puzzle, and we only have a few pieces…. But the more pieces we have, the better chance we have to understand life during that time.”

    The new fossil trove, called the Qingjiang biota, was first spotted in 2007, says coauthor Xingliang Zhang, a paleontologist also at Northwest University. “I have been working on Burgess Shale–type fossils for many years, and know what kind of rocks preserve [them],” Zhang says.

    During a field expedition that year, he and his students were investigating a different rock layer dating to the Cambrian. At lunchtime, he says, he happened to sit on the next lower layer of rocks as it was being lapped by the river’s water — and immediately recognized that the fine clay layer was the perfect preservation setting for fossils. “We split the clay stone and I found a Leanchoilia [a kind of segmented arthropod] quickly.” Many more discoveries soon followed.

    The site is remarkable for the quality of the preservation of the animals, says Allison Daley, a paleontologist at the University of Lausanne in Switzerland who was not involved in the new study but wrote a Science commentary that accompanies it in Science. “There was very little metamorphism or weathering effect, which does affect some other [Cambrian fossil] sites, like Burgess or Chengjiang. We see almost pristine fossils at this site.” She mentions one startlingly clear image of a jellyfish. “I mean, if you were going to smack a jellyfish on a rock, that’s how it would look.”

    ________________________________________________________
    Weird wonders
    The excellent preservation of the Qingjiang fossils reveals fine morphological details of some of the life-forms that lived in Cambrian seas, such as a branched alga (left) and the segmented body of an arthropod called a megacherian (right).
    3
    ________________________________________________________

    Unlike other Cambrian fossil troves, the Qingjiang biota appears to contain a high proportion of jellyfish, or cnidarians, and comb jellies, also called ctenophores. These species, particularly the comb jellies, are extremely rare at other sites.

    With so many ctenophore fossils preserved so well, Daley says, studying their shapes may help to answer a long-standing debate: Whether comb jellies or sponges are the most primitive animal on their family tree. Scientists have thought that sponges appear closer to the base of the tree, based on their very simple shapes. But some molecular analyses have hinted that comb jellies may be at the base of the tree.

    “It’s hard to disentangle the exact relationships of these [creatures],” Daley says. “These early branching groups diverged from each other such a long time ago…. So getting more info on [them] at this new site, where the preservation is really amazing, is really going to fill a gap.”

    The Burgess Shale, a vast deposit of fossil-bearing rocks in the Canadian Rockies, was discovered in 1909. It was this site that first gave scientists a glimpse into the Cambrian explosion, the rapid diversification of life that occurred during that period. The Burgess and Chengjiang sites, separated by 10 million years and half a world today, share only about 15 percent of the same taxa.

    That might be expected, Daley says, given their differences in both space and time. But the Qingjiang and Chengjiang sites, which date to the same time period and are separated by only 1,050 kilometers today, share only 8 percent of their taxa, she says. The researchers, however, suggest that the Qingjiang site may have been a slightly deeper marine environment. If so, that difference in ancient environment may have been the reason why the assemblage of creatures is so different, Daley says.

    The new work is preliminary, representing just the first of what is likely to be a deluge of studies describing fossils found at the site, Zhang says. “We’re just beginning!”

    Even after 110 years of digging in the Burgess Shale region, paleontologists are still turning up rich new sites and bizarre new creatures, adds Caron, of Canada’s Royal Ontario Museum. Just last summer, he and colleagues made new discoveries, including an enigmatic shield-shaped critter that he dubbed “the mothership.” Unlike other Cambrian fossil troves, the Qingjiang biota appears to contain a high proportion of jellyfish, or cnidarians, and comb jellies, also called ctenophores. These species, particularly the comb jellies, are extremely rare at other sites.

    With so many ctenophore fossils preserved so well, Daley says, studying their shapes may help to answer a long-standing debate: Whether comb jellies or sponges are the most primitive animal on their family tree. Scientists have thought that sponges appear closer to the base of the tree, based on their very simple shapes. But some molecular analyses have hinted that comb jellies may be at the base of the tree.

    “It’s hard to disentangle the exact relationships of these [creatures],” Daley says. “These early branching groups diverged from each other such a long time ago…. So getting more info on [them] at this new site, where the preservation is really amazing, is really going to fill a gap.”

    The Burgess Shale, a vast deposit of fossil-bearing rocks in the Canadian Rockies, was discovered in 1909. It was this site that first gave scientists a glimpse into the Cambrian explosion, the rapid diversification of life that occurred during that period. The Burgess and Chengjiang sites, separated by 10 million years and half a world today, share only about 15 percent of the same taxa.

    That might be expected, Daley says, given their differences in both space and time. But the Qingjiang and Chengjiang sites, which date to the same time period and are separated by only 1,050 kilometers today, share only 8 percent of their taxa, she says. The researchers, however, suggest that the Qingjiang site may have been a slightly deeper marine environment. If so, that difference in ancient environment may have been the reason why the assemblage of creatures is so different, Daley says.

    The new work is preliminary, representing just the first of what is likely to be a deluge of studies describing fossils found at the site, Zhang says. “We’re just beginning!”

    Even after 110 years of digging in the Burgess Shale region, paleontologists are still turning up rich new sites and bizarre new creatures, adds Caron, of Canada’s Royal Ontario Museum. Just last summer, he and colleagues made new discoveries, including an enigmatic shield-shaped critter that he dubbed “the mothership.”

    See the full article here .


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  • richardmitnick 11:37 am on March 4, 2019 Permalink | Reply
    Tags: "How Creatures End Up Miles Below the Surface of Earth and Maybe Mars Too", An inevitable and most interesting question that arises is this: If there was robust and adaptable life on early Mars might it have been transported underground in water too?, At the Kopanang mine they had found the roundworm Poikilolaimus oxycercusin in water about a mile underground. What appeared to be the same nematode was also collected from the the Vaal river a few mi, “M. parvella does not have a hibernation stage and cannot survive in fresh water thus it must have been and must be in brackish water all the time” Borgonie said. “The question is did this happe, , , Ecosystems can survive in scalding temperatures in the absence of sunlight at high pressure and without oxygen. Yet they have been found as far down as almost three miles below the surface though in f, H. mephisto, , Paleobiology, Recent reports of another nematode species unaffiliated with South African mines suggests just how robust and adaptable individuals can be — in this case regarding deep freeze hibernation., Round worm Poikilolaimus oxycercus, Salese and colleagues explored 24 deep enclosed craters in the northern hemisphere of Mars with floors lying roughly 4000 meters (2.5 miles) below Martian ‘sea level’ (a level that given the plane, Some potential early Martian life could have migrated into the more protected depths is often discussed as a plausible if at this point untestable possibility   

    From Many Worlds: “How Creatures End Up Miles Below the Surface of Earth, and Maybe Mars Too” 

    NASA NExSS bloc

    NASA NExSS

    Many Words icon

    From Many Worlds

    2019-03-04
    Marc Kaufman

    1
    Poikilolaimus oxycercus is a microscopic nematode, or roundworm, found alive and well more than a mile below the surface in South Africa, where its ancestors had lived for hundreds or thousands of years. (Gaetan Borgonie)

    When scientists speculate about possible life on Mars, they generally speak of microbial or other simple creatures living deep below the irradiated and desiccated surface. While Mars long ago had a substantial period that was wetter and warmer when it also had a far more protective atmosphere, the surface now is considered to be lethal.

    But the suggestion that some potential early Martian life could have migrated into the more protected depths is often discussed as a plausible, if at this point untestable possibility. In this scenario, some of that primitive subsurface life might even have survived the eons in their buried, and protected, environments.

    This thinking has gotten some support in the past decade with the discovery of bacteria and nematodes (roundworms) found as far down as three miles below the surface of South Africa, in water dated as being many thousands or millions years old. The lifeforms have been discovered by a team that has regularly gone down into the nation’s super-hot gold and platinum mines to search for life coming out of boreholes in the rock face of deep mine tunnels.

    2
    Borgonie setting up a water collector for a borehole at the Driefontein mine in the Witwatersrand Basin of South Africa. (Courtesy of Borgonie)

    Now a new paper [below] describes not only the discovery of additional deep subsurface life, but also tries to explain how the distant ancestors of the worms and bacteria and algae might have gotten there.

    Their conclusion: many were pulled down when fractures opened in the aftermath of earthquakes and other seismic events. While many lifeforms were swept down, only a small percentage were able to adapt, evolve and thus survive.

    The is how Gaetan Borgonie, lead author of the paper in Scientific Reports, explained it to me via email:

    “After the discovery of multicellular animals in the deep subsurface up to 3.8 km (2.5 miles) in South Africa everyone was baffled and asked the question how did they get that deep? This question more or less haunted us for more than a decade as we were unable to get our head around it.

    “However during the decade as we made more observations of multicellular organisms we captured in borehole water we found that these were nearly all animals associated with fresh water and not the soil. This indicated the passage to the deep was from a fresh water source on the surface and that animals did not crawl all the way down through the topsoil over millennia.”

    This makes sense because the deepest soil inhabitants live at about six feet below the surface, said Borgonie, formerly of the University of Ghent in Belgium and now with ELi, a Belgian nonprofit that studies extreme life. So another route to their deep subterranean homes was necessary.

    3
    One of six hibernating nematodes found in biofilms from a borehole in the Kopanang mine. Four of the six in this “dauer” or survival state were taken, placed in a petri dish and came back to active life. Several were mated with worms of the same Poikilolaimus oxycercus species and the offspring survived. (Gaetan Borgonie)

    Borgonie and his team conducted a variety of tests — seismic, geological, genetic — but one stands out as most conclusive.

    At the Kopanang mine, they had found the roundworm Poikilolaimus oxycercusin in water about a mile underground. What appeared to be the same nematode was also collected from the the Vaal river, a few miles from the mine.

    The two appeared to be genetically similar, but the best test was to see if they could successfully reproduce. And the answer was that they could.

    It was a smoking gun, though not necessarily a common one. Nematodes from other surfaces and subsurfaces were placed together and were not able to produce young that survived. As explained in the Scientific Reports paper, this may be a function of the once companionable subsurface nematodes having adapted to their environment in ways that broke their connections with surface nematodes of the same species.

    While nematodes can hibernate for long periods in what is called their dauer stage, when they wake up they survive for only 20 to 30 days. Their lines, however, can last in the subsurface for those very long periods.

    4
    Tunnels in South Africa’s Beatrix mine close to where H. mephisto was found. The deeper one goes in the mine, the hotter it gets. And yet life survives in the fracture water and other often tiny pockets of liquid. (Gaetan Borgonie)

    The nematodes collected and tested for this most recent article were but a small part of the zoo of creatures that have been collected from deep underground in South Africa’s Witwatersrand Basin. There was also algae, fungi, bacteria, a crustaceans and even a few insects, the paper reports. The bacteria is important for the nematodes in particular because they are a food source.

    These ecosystems survive in scalding temperatures, in the absence of sunlight, at high pressure and without oxygen. Yet they have been found as far down as almost three miles below the surface, though in far more isolated conditions at that depth.

    5
    Borgonie with Esta van Heerden, who helped gain access to South African mines for researchers including Borgonie and Princeton University geomicrobiologist Tullis Onstott more than a decade ago is part of their research team. She is founder of the mine water remediation company iwatersolutions and was formerly a professor with the University of the Free State in Bloemfontein, where she was a specialist in extremophiles. (Courtesy of Borgonie)

    The age of that life is difficult to determine. While methods exist to determine the age of the fracture water, scientists cannot definitively say when the lifeforms arrived. Still, Borgonie reports that the worms found at the Kopanang mine had been present for between 3,000 and 12,000 years, or rather their ancestors had been there.

    Borgonie and his colleagues had earlier discovered the first multicellular creature at great depth, Halicephalobus mephisto, in mine fracture water .6 to 3 miles down. That discovery, announced in 2011, helped establish that the deep subsurface was more able to support life, even complex life, than expected.

    Often the creatures were living in biofilms, loose collections of bacteria and other life held together in the water by secretions that encase them.

    Another aspect of the deep subsurface nematode story involves specimen found in salty stalactites at the Beatrix gold mine. The worms identified, Monhystrella parvella, are associated with salty environments and so the group inferred that the water and creatures may have come from a sea. There were such seas in what is now South Africa, but it was very long ago.

    “M. parvella does not have a hibernation stage and cannot survive in fresh water, thus it must have been and must be in brackish water all the time,” Borgonie said. “The question is did this happen long ago when that area of South Africa was covered by a sea or did it happen via the salt pans surrounding the Beatrix mine?

    “There is no way to know for now. But the fact is and remains that you have a worm in the subsurface in the middle of South Africa that can only survive in salty water.”

    Recent reports of another nematode species, unaffiliated with South African mines, suggests just how robust and adaptable individuals can be — in this case regarding deep freeze hibernation.

    The longest recorded nematode hibernation was 39 years until Russian scientists announced the discovery of frozen nematodes in deep Siberian permafrost. The worms had been asleep for 42,000 and 34,000 years respectively. A Science Alert article raises the possibility of contamination as an issue, but the scientists maintain they took all possible precautions and are convinced the frozen hibernations were as recorded.

    6
    Using an electron microscope, we see the inside of a stalactite in the Beatrix gold mine, about 1 mile below the surface. The nematodes are of the species Monhystrella parvella. (Gaetan Borgonie)

    That the South African deep subsurface life appears now to have come from the surface — via seismic fractures that could bring rushes or trickles of water filled with life many miles down — does have possible implications for Mars. While no signs of early life on Mars have been discovered, research in recent years has proven that the planet once had substantial water and warmer temperatures. In other words, conditions that might be hospitable to life.

    That theory of a once quite watery Mars was taken a significant step further last week in an article in the Journal of Geophysical Research — Planets , which found evidence of an earlier planet-wide groundwater system. Such a system had been predicted before by models, but now there was significant hard evidence that it had indeed existed.

    “Early Mars was a watery world, but as the planet’s climate changed this water retreated below the surface to form pools and ‘groundwater’,” says lead author Francesco Salese of Utrecht University, the Netherlands.

    “We traced this water in our study — as its scale and role is a matter of debate — and we found the first geological evidence of a planet-wide groundwater system on Mars.”

    Salese and colleagues explored 24 deep, enclosed craters in the northern hemisphere of Mars, with floors lying roughly 4000 meters (2.5 miles) below Martian ‘sea level’ (a level that, given the planet’s lack of seas, is arbitrarily defined on Mars based on elevation and atmospheric pressure).

    The scientists found features on the floors of these craters that could only have formed in the presence of water. Many craters contain multiple features, all at depths of 2.5 to 3 miles – indicating that these craters once contained pools and flows of water that changed and receded over time.

    7
    Researchers said flow channels, pool-shaped valleys and fan-shaped sediment deposits seen in dozens of kilometers-deep craters in Mars’ northern hemisphere would have needed water to form. (European Space Agency)

    So an inevitable and most interesting question that arises is this: If there was robust and adaptable life on early Mars, might it have been transported underground in water too?

    The planet does have seismic activity — some are called Marsquakes — that can open fractures. It seems plausible that if life existed in water on the Martian surface, it would have flowed or trickled down fractures and other porous features to substantial depths.

    Given this hypothetical, many would have died but some may have lived and adapted. Rather like what can be seen on Earth in the South African mines.

    With this possibility in mind, the Borgonie paper recommends that the presence of surface fractures be kept in mind when landing sites are chosen on other planets or moons.

    See the full article here .


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    About Many Worlds
    There are many worlds out there waiting to fire your imagination.

    Marc Kaufman is an experienced journalist, having spent three decades at The Washington Post and The Philadelphia Inquirer, and is the author of two books on searching for life and planetary habitability. While the “Many Worlds” column is supported by the Lunar Planetary Institute/USRA and informed by NASA’s NExSS initiative, any opinions expressed are the author’s alone.

    This site is for everyone interested in the burgeoning field of exoplanet detection and research, from the general public to scientists in the field. It will present columns, news stories and in-depth features, as well as the work of guest writers.

    About NExSS

    The Nexus for Exoplanet System Science (NExSS) is a NASA research coordination network dedicated to the study of planetary habitability. The goals of NExSS are to investigate the diversity of exoplanets and to learn how their history, geology, and climate interact to create the conditions for life. NExSS investigators also strive to put planets into an architectural context — as solar systems built over the eons through dynamical processes and sculpted by stars. Based on our understanding of our own solar system and habitable planet Earth, researchers in the network aim to identify where habitable niches are most likely to occur, which planets are most likely to be habitable. Leveraging current NASA investments in research and missions, NExSS will accelerate the discovery and characterization of other potentially life-bearing worlds in the galaxy, using a systems science approach.
    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

     
  • richardmitnick 3:23 pm on February 27, 2019 Permalink | Reply
    Tags: A one-stop link allowing earth scientists to access all the data they need to tackle big questions such as patterns of biodiversity over geologic time and the distribution of metal deposits also the w, , British Geological Survey, , Paleobiology, , This network of earth science databases called Deep-time Digital Earth (DDE)   

    From Science Magazine: “Earth scientists plan to meld massive databases into a ‘geological Google’’ 

    AAAS
    From Science Magazine

    Feb. 26, 2019
    Dennis Normile

    1
    Deep-time Digital Earth aims to liberate data from collections such as the British Geological Survey’s. British Geological Survey.

    The British Geological Survey (BGS) has amassed one of the world’s premier collections of geologic samples. Housed in three enormous warehouses in Nottingham, U.K., it contains about 3 million fossils gathered over more than 150 years at thousands of sites across the country. But this data trove “was not really very useful to anybody,” says Michael Stephenson, a BGS paleontologist. Notes about the samples and their associated rocks “were sitting in boxes on bits of paper.” Now, that could change, thanks to a nascent international effort to meld earth science databases into what Stephenson and other backers are describing as a “geological Google.”

    This network of earth science databases, called Deep-time Digital Earth (DDE), would be a one-stop link allowing earth scientists to access all the data they need to tackle big questions, such as patterns of biodiversity over geologic time, the distribution of metal deposits, and the workings of Africa’s complex groundwater networks. It’s not the first such effort, but it has a key advantage, says Isabel Montañez, a geochemist at University of California, Davis, who is not involved in the project: funding and infrastructure support from the Chinese government. That backing “will be critical to [DDE’s] success given the scope of the proposed work,” she says.

    In December 2018, DDE won the backing of the executive committee of the International Union of Geological Sciences, which said ready access to the collected geodata could offer “insights into the distribution and value of earth’s resources and materials, as well as hazards—while also providing a glimpse of the Earth’s geological future.” At a meeting this week in Beijing, 80 scientists from 40 geoscience organizations including BGS and the Russian Geological Research Institute are discussing how to get DDE up and running by the time of the International Geological Congress in New Delhi in March 2020.

    DDE grew out of a Chinese data digitization scheme called the Geobiodiversity Database (GBDB), initiated in 2006 by Chinese paleontologist Fan Junxuan of Nanjing University. China had long-running efforts in earth sciences, but the data were scattered among numerous collections and institutions. Fan, who was then at the Chinese Academy of Sciences’s Nanjing Institute of Geology and Paleontology, organized GBDB around the stacks of geologic strata called sections and the rocks and fossils in each stratum.

    Norman MacLeod, a paleobiologist at the Natural History Museum in London who is advising DDE, says GBDB has succeeded where similar efforts have stumbled. In the past, he says, volunteer earth scientists tried to do nearly everything themselves, including informatics and data management. GBDB instead pays nonspecialists to input reams of data gleaned from earth science journals covering Chinese findings. Then, paleontologists and stratigraphers review the data for accuracy and consistency, and information technology specialists curate the database and create software to search and analyze the data. Consistent funding also contributed to GBDB’s success, MacLeod says. Although it started small, Fan says GBDB now runs on “several million” yuan per year.

    Earth scientists outside China began to use GBDB, and it became the official database of the International Commission on Stratigraphy in 2012. BGS decided to partner with GBDB to lift its data “from the page and into cyberspace,” as Stephenson puts it. He and other European and Chinese scientists then began to wonder whether the informatics tools developed for GBDB could help create a broader union of databases. “Our idea is to take these big databases and make them use the same standards and references so a researcher could quickly link them to do big science that hasn’t been done before,” he says.

    The Beijing meeting aims to finalize an organizational structure for DDE. Chinese funding agencies are putting up $75 million over 10 years to get the effort off the ground, Fan says. That level of support sets DDE apart from other cyberinfrastructure efforts “that are smaller in scope and less well funded,” Montañez says. Fan hopes DDE will also attract international support. He envisions nationally supported DDE Centers of Excellence that would develop databases and analytical tools for particular interests. Suzhou, China, has already agreed to host the first of them, which will also house the DDE secretariat.

    DDE backers say they want to cooperate with other geodatabase programs, such as BGS’s OneGeology project, which seeks to make geologic maps of the world available online. But Mohan Ramamurthy, project director of the U.S. National Science Foundation–funded EarthCube project, sees little scope for collaboration with his effort, which focuses on current issues such as climate change and biosphere-geosphere interactions. “The two programs have very different objectives with little overlap,” he says.

    Fan also hopes individual institutions will contribute, by sharing data, developing analytical tools, and encouraging their scientists to participate. Once earth scientists are freed of the drudgery of combing scattered collections, he says, they will have time for more important challenges, such as answering “questions about the evolution of life, materials, geography, and climate in deep time.”

    See the full article here .


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  • richardmitnick 12:41 pm on May 26, 2016 Permalink | Reply
    Tags: , Paleobiology, Tiny Vampires, ,   

    From UCSB: “Tiny Vampires” Women in Science (No, the women are not the vampires in question) 

    UC Santa Barbara Name bloc

    May 25, 2016
    Julie Cohen

    1
    Susannah Porter. Photo Credit: Sonia Fernandez

    Paleobiologist Susannah Porter finds evidence of predation in ancient microbial ecosystems dating back more than 740 million years.

    2
    The Chuar Group in the Grand Canyon was once an ancient seabed. Photo Credit: Carol Dehler

    Vampires are real, and they’ve been around for millions of years. At least, the amoebae variety has. So suggests new research from UC Santa Barbara paleobiologist Susannah Porter.

    Using a scanning electron microscope to examine minute fossils, Porter found perfectly circular drill holes that may have been formed by an ancient relation of Vampyrellidae amoebae. These single-celled creatures perforate the walls of their prey and reach inside to consume its cell contents. Porter’s findings* appear in the Proceedings of the Royal Society B.

    “To my knowledge these holes are the earliest direct evidence of predation on eukaryotes,” said Porter, an associate professor in UCSB’s Department of Earth Science. Eukaryotes are organisms whose cells contain a nucleus and other organelles such as mitochondria.

    “We have a great record of predation on animals going back 550 million years,” she continued, “starting with the very first mineralized shells, which show evidence of drillholes. We had nothing like that for early life — for the time before animals appear. These holes potentially provide a way of looking at predator-prey interactions in very deep time in ancient microbial ecosystems.”

    Porter examined fossils from the Chuar Group in the Grand Canyon — once an ancient seabed — that are between 782 and 742 million years old. The holes are about one micrometer (one thousandth of a millimeter) in diameter and occur in seven of the species she identified. The holes are not common in any single one species; in fact, they appear in not more than 10 percent of the specimens.

    “I also found evidence of specificity in hole sizes, so different species show different characteristic hole sizes, which is consistent with what we know about modern vampire amoebae and their food preferences,” Porter said. “Different species of amoebae make differently sized holes. The Vampyrellid amoebae make a great modern analog, but because vampirelike feeding behavior is known in a number of different unrelated amoebae, it makes it difficult to pin down exactly who the predator was.”

    According to Porter, this evidence may help to address the question of whether predation was one of the driving factors in the diversification of eukaryotes that took place about 800 million years ago.

    “If that is true, then if we look at older fossil assemblages — say 1 to 1.6 billion years old — the fossilized eukaryote will show no evidence of predation,” Porter said. “I’m interested in finding out when drilling first appears in the fossil record and whether its intensity changes through time.”

    Porter also is interested in seeing whether oxygen played a role in predation levels through time. She noted that the microfossils those organisms attacked were probably phytoplankton living in oxygenated surface waters, but like vampyrellid amoebae today, the predators may have lived in the sediments. She suggests that those phytoplankton made tough-walled cysts — resting structures now preserved as fossils — that sank to the bottom where they were attacked by the amoebae.

    “We have evidence that the bottom waters in the Chuar Group in that Grand Canyon basin were relatively deep — 200 meters deep at most — and sometimes became anoxic, meaning they lacked oxygen,” Porter explained.

    “I’m interested to know whether the predators only were present and making these drill holes when the bottom waters contained oxygen,” Porter added. “That might tie the diversification of eukaryotes and the appearance of predators to evidence for increasing oxygen levels around 800 million years ago.

    “We know from the modern vampire amoebae that at least some of them make resting cysts themselves,” Porter said. “A former student of mine joked we should call these coffins. So one of our motivations is to see if we can find these coffins in the fossil assemblage as well. That’s the next project.”

    *Science paper:
    Tiny vampires in ancient seas: evidence for predation via perforation in fossils from the 780–740 million-year-old Chuar Group, Grand Canyon, USA

    See the full article here .

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    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
  • richardmitnick 12:17 pm on February 17, 2015 Permalink | Reply
    Tags: , , , Paleobiology,   

    From U Washington: “Ancient rocks show life could have flourished on Earth 3.2 billion years ago” 

    U Washington

    University of Washington

    February 16, 2015
    Hannah Hickey

    1
    The oldest samples are sedimentary rocks that formed 3.2 billion years ago in
    northwestern Australia. They contain chemical evidence for nitrogen fixation by microbes. (R. Buick / UW)

    A spark from a lightning bolt, interstellar dust, or a subsea volcano could have triggered the very first life on Earth.

    But what happened next? Life can exist without oxygen, but without plentiful nitrogen to build genes – essential to viruses, bacteria and all other organisms – life on the early Earth would have been scarce.

    The ability to use atmospheric nitrogen to support more widespread life was thought to have appeared roughly 2 billion years ago. Now research from the University of Washington looking at some of the planet’s oldest rocks finds evidence that 3.2 billion years ago, life was already pulling nitrogen out of the air and converting it into a form that could support larger communities.

    “People always had the idea that the really ancient biosphere was just tenuously clinging on to this inhospitable planet, and it wasn’t until the emergence of nitrogen fixation that suddenly the biosphere become large and robust and diverse,” said co-author Roger Buick, a UW professor of Earth and space sciences. “Our work shows that there was no nitrogen crisis on the early Earth, and therefore it could have supported a fairly large and diverse biosphere.”

    The results were published Feb. 16 in Nature.

    The authors analyzed 52 samples ranging in age from 2.75 to 3.2 billion years old, collected in South Africa and northwestern Australia. These are some of the oldest and best-preserved rocks on the planet. The rocks were formed from sediment deposited on continental margins, so are free of chemical irregularities that would occur near a subsea volcano. They also formed before the atmosphere gained oxygen, roughly 2.3 to 2.4 billion years ago, and so preserve chemical clues that have disappeared in modern rocks.

    Even the oldest samples, 3.2 billion years old – three-quarters of the way back to the birth of the planet – showed chemical evidence that life was pulling nitrogen out of the air. The ratio of heavier to lighter nitrogen atoms fits the pattern of nitrogen-fixing enzymes contained in single-celled organisms, and does not match any chemical reactions that occur in the absence of life.

    “Imagining that this really complicated process is so old, and has operated in the same way for 3.2 billion years, I think is fascinating,” said lead author Eva Stüeken, who did the work as part of her UW doctoral research. “It suggests that these really complicated enzymes apparently formed really early, so maybe it’s not so difficult for these enzymes to evolve.”

    Genetic analysis of nitrogen-fixing enzymes have placed their origin at between 1.5 and 2.2 billion years ago.

    “This is hard evidence that pushes it back a further billion years,” Buick said.

    Fixing nitrogen means breaking a tenacious triple bond that holds nitrogen atoms in pairs in the atmosphere and joining a single nitrogen to a molecule that is easier for living things to use. The chemical signature of the rocks suggests that nitrogen was being broken by an enzyme based on molybdenum, the most common of the three types of nitrogen-fixing enzymes that exist now. Molybdenum is now abundant because oxygen reacts with rocks to wash it into the ocean, but its source on the ancient Earth – before the atmosphere contained oxygen to weather rocks – is more mysterious*.

    The authors hypothesize that this may be further evidence that some early life may have existed in single-celled layers on land, exhaling small amounts of oxygen that reacted with the rock to release molybdenum to the water.

    “We’ll never find any direct evidence of land scum one cell thick, but this might be giving us indirect evidence that the land was inhabited,” Buick said. “Microbes could have crawled out of the ocean and lived in a slime layer on the rocks on land, even before 3.2 billion years ago.”

    Future work will look at what else could have limited the growth of life on the early Earth. Stüeken has begun a UW postdoctoral position funded by NASA to look at trace metals such as zinc, copper and cobalt to see if one of them controlled the growth of ancient life.

    Other co-authors are Bradley Guy at the University of Johannesburg in South Africa, who provided some samples from gold mines, and UW graduate student Matthew Koehler. The research was funded by NASA, the UW’s Virtual Planetary Laboratory, the Geological Society of America and the Agouron Institute.

    See the full article here.

    [*Sorry, not mysterious at all. Everything here, especially metals, comes from the ash of supernovae.]

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    So what defines us — the students, faculty and community members at the University of Washington? Above all, it’s our belief in possibility and our unshakable optimism. It’s a connection to others, both near and far. It’s a hunger that pushes us to tackle challenges and pursue progress. It’s the conviction that together we can create a world of good. Join us on the journey.

     
  • richardmitnick 9:13 am on February 3, 2015 Permalink | Reply
    Tags: , Microorganisms, Paleobiology, ,   

    From UCLA: “Scientists discover organism that hasn’t evolved in more than 2 billion years” 

    UCLA bloc

    UCLA

    February 02, 2015
    Stuart Wolpert

    1
    A section of 1.8 billion-year-old fossil-bearing rock. The fossils (dark areas) are essentially identical to fossils 500 million years older and to modern microorganisms.
    UCLA Center for the Study of Evolution and the Origin of Life

    Research actually provides further support for Darwin, UCLA professor says

    An international team of scientists has discovered the greatest absence of evolution ever reported — a type of deep-sea microorganism that appears not to have evolved over more than 2 billion years. But the researchers say that the organisms’ lack of evolution actually supports Charles Darwin’s theory of evolution.

    The findings are published online today by the Proceedings of the National Academy of Sciences.

    The scientists examined sulfur bacteria, microorganisms that are too small to see with the unaided eye, that are 1.8 billion years old and were preserved in rocks from Western Australia’s coastal waters. Using cutting-edge technology, they found that the bacteria look the same as bacteria of the same region from 2.3 billion years ago — and that both sets of ancient bacteria are indistinguishable from modern sulfur bacteria found in mud off of the coast of Chile.

    “It seems astounding that life has not evolved for more than 2 billion years — nearly half the history of the Earth,” said J. William Schopf, a UCLA professor of earth, planetary and space sciences in the UCLA College who was the study’s lead author. “Given that evolution is a fact, this lack of evolution needs to be explained.”

    3
    Deep-sea microorganisms are unchanged over more than 2 billion years (UCLA Center for the Study of Evolution and the Origin of Life)

    Charles Darwin’s writings on evolution focused much more on species that had changed over time than on those that hadn’t. So how do scientists explain a species living for so long without evolving?

    2
    UCLA professor J. William Schopf pioneered the techniques used to analyze microscopic fossils preserved inside ancient rocks.(John Vande Wege/UCLA)

    “The rule of biology is not to evolve unless the physical or biological environment changes, which is consistent with Darwin,” said Schopf, who also is director of UCLA’s Center for the Study of Evolution and the Origin of Life. The environment in which these microorganisms live has remained essentially unchanged for 3 billion years, he said.

    “These microorganisms are well-adapted to their simple, very stable physical and biological environment,” he said. “If they were in an environment that did not change but they nevertheless evolved, that would have shown that our understanding of Darwinian evolution was seriously flawed.”

    Schopf said the findings therefore provide further scientific proof for Darwin’s work. “It fits perfectly with his ideas,” he said.

    The fossils Schopf analyzed date back to a substantial rise in Earth’s oxygen levels known as the Great Oxidation Event, which scientists believe occurred between 2.2 billion and 2.4 billion years ago. The event also produced a dramatic increase in sulfate and nitrate — the only nutrients the microorganisms would have needed to survive in their seawater mud environment — which the scientists say enabled the bacteria to thrive and multiply.

    Schopf used several techniques to analyze the fossils, including Raman spectroscopy — which enables scientists to look inside rocks to determine their composition and chemistry — and confocal laser scanning microscopy — which renders fossils in 3-D. He pioneered the use of both techniques for analyzing microscopic fossils preserved inside ancient rocks.

    Co-authors of the PNAS research were Anatoliy Kudryavtsev, a senior scientist at UCLA’s Center for the Study of Evolution and the Origin of Life, and scientists from the University of Wisconsin, NASA’s Jet Propulsion Laboratory, Australia’s University of New South Wales and Chile’s Universidad de Concepción.

    Schopf’s research is funded by the NASA Astrobiology Institute.

    See the full article here.

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    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 4:23 am on January 29, 2015 Permalink | Reply
    Tags: , , Paleobiology, ,   

    From U Alberta: “Long-necked ‘dragon’ discovered in China “ 

    U Alberta bloc

    University of Alberta

    January 28, 2015
    Kristy Condon

    2
    Artist’s conception of Qijianglong, chased by two carnivorous dinosaurs in southern China 160 million years ago (Illustration: Lida Xing)

    University of Alberta paleontologists including PhD student Tetsuto Miyashita, former master’s student Lida Xing and professor Philip Currie have discovered a new species of a long-necked dinosaur from a skeleton found in China. The findings have been published in a new paper in the Journal of Vertebrate Paleontology.

    Qijianglong (pronounced “CHI-jyang-lon”) is about 15 metres long and lived about 160 million years ago in the Late Jurassic. The name means “dragon of Qijiang,” for its discovery near Qijiang City, close to Chongqing. The fossil site was found by construction workers in 2006, and the digging eventually hit a series of large neck vertebrae stretched out in the ground. Incredibly, the head of the dinosaur was still attached.

    “It is rare to find a head and neck of a long-necked dinosaur together because the head is so small and easily detached after the animal dies,” explains Miyashita.

    The new species belongs to a group of dinosaurs called mamenchisaurids, known for their extremely long necks sometimes measuring up to half the length of their bodies. Most sauropods, or long-necked dinosaurs, have necks only about one-third the length of their bodies.

    Unique among mamenchisaurids, Qijianglong had neck vertebrae that were filled with air, making their necks relatively lightweight despite their enormous size. Interlocking joints between the vertebrae also indicate a surprisingly stiff neck that was much more mobile bending vertically than sideways, similar to a construction crane.
    Dino101

    “Qijianglong is a cool animal. If you imagine a big animal that is half neck, you can see that evolution can do quite extraordinary things,” says Miyashita.

    Mamenchisaurids are only found in Asia, but the discovery of Qijianglong reveals that there could be as many differences among mamenchisaurids as there are between long-necked dinosaurs from different continents.

    “Qijianglong shows that long-necked dinosaurs diversified in unique ways in Asia during Jurassic times—something very special was going on in that continent,” says Miyashita. “Nowhere else we can find dinosaurs with longer necks than those in China. The new dinosaur tells us that these extreme species thrived in isolation from the rest of the world.”

    Miyashita believes that mamenchisaurids evolved into many different forms when other long-necked dinosaurs went extinct in Asia. “It is still a mystery why mamenchisaurids did not migrate to other continents,” he says. It is possible that the dinosaurs were once isolated as a result of a large barrier such as a sea, and lost in competition with invading species when the land connection was later restored.

    The Qijianglong skeleton is now housed in a local museum in Qijiang. “China is home to the ancient myths of dragons,” says Miyashita. “I wonder if the ancient Chinese stumbled upon a skeleton of a long-necked dinosaur like Qijianglong and pictured that mythical creature.” – See more at: http://uofa.ualberta.ca/news-and-events/newsarticles/2015/january/long-necked-dragon-discovered-in-china#sthash.ZCpknCAJ.dpuf

    See the full article here.

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    The University of Alberta’s has had the vision to be one of the world’s great universities for the public good since its inception. This university is dedicated to the promise made by founding president Henry Marshall Tory that “… knowledge shall not be the concern of scholars alone. The uplifting of the whole people shall be its final goal.”

     
  • richardmitnick 11:18 am on January 27, 2015 Permalink | Reply
    Tags: , , , Paleobiology,   

    From LLNL: “Lawrence Livermore research finds early Mesoamericans affected by climate change” 


    Lawrence Livermore National Laboratory

    Jan. 26, 2015

    Anne M Stark
    stark8@llnl.gov
    925-422-9799

    1
    Cantona was one of the largest cities in pre-Columbian Mesoamerica, with a population of 90,000 inhabitants at its peak. Scientists believe climate change was part of the reason the city was eventually abandoned.

    Scientists have reconstructed the past climate for the region around Cantona, a large fortified city in highland Mexico, and found the population drastically declined in the past, at least in part because of climate change.

    The research appears in the online edition of the Proceedings of the National Academy of Sciences for the week of Jan. 26.

    Lawrence Livermore researcher Susan Zimmerman and colleagues analyzed pollen, stable isotopes and elemental concentrations, which serve as proxies of past climatic and environmental conditions, from lake sediments in the region and found evidence of a regional drought between 500 and 1150 AD*, about the time Cantona was abandoned.

    Using Lawrence Livermore’s Center for Accelerator Mass Spectrometry, the team — consisting of the University of California, Berkeley; Universidad Nacional Autonóma de Mexico; and the GFZ German Research Center for Geosciences — dated terrestrial organic material from 12-meter-long sediment cores from the lake to establish the age control for this study. Radiocarbon dating and an age model showed that the centennial-scale arid interval between 500 and 1150 was overlaid on a long-term drying trend. The cores cover the last 6,200 years; however, the team focused on the last 3,800 years.

    2

    Cantona is now an archaeological site in Mexico, on the border with Veracruz, about an hour’s drive from the city of Puebla. Limited archaeological work has been done at the site, and only about 10 percent of the site can be seen. It was a prominent, if isolated, Mesoamerican city between 600 and 1000 AD. It was abandoned after 1050 AD.

    “We found that Cantona’s population grew in the initial phases of the drought, but by 1050 AD long-term environmental stress (the drought) contributed to the city’s abandonment,” Zimmerman and colleagues said. “Our research highlights the interplay of environmental and political factors in past human responses to climate change.”

    Cantona was one of the largest cities in pre-Columbian Mesoamerica, with a population of 90,000 inhabitants. It is in a semiarid basin east of Mexico City.

    The team conducted a subcentennial reconstruction of regional climate by taking sediment samples from a nearby crater lake, Aljojuca. The modern climate of the region suggests that proxy data from the sediments record changes in summer monsoonal (May through October) precipitation.

    “Our results suggest that climate change played a contributing role in the site’s history,” Zimmerman said.

    *LLNL has been apprised of the fact that the use of “AD” and “BC” as terms for dating is now out of use, AD replaced by CE, BC replaced by BCE

    See the full article here.

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  • richardmitnick 5:23 am on January 20, 2015 Permalink | Reply
    Tags: , Paleobiology, ,   

    From Yale: “Fossil ankles indicate Earth’s earliest primates lived in trees” 

    Yale University bloc

    Yale University

    1
    (Illustration by Patrick Lynch)

    Earth’s earliest primates have taken a step up in the world, now that researchers have gotten a good look at their ankles.

    A new study has found that Purgatorius, a small mammal that lived on a diet of fruit and insects, was a tree dweller. Paleontologists made the discovery by analyzing 65-million-year-old ankle bones collected from sites in northeastern Montana.

    Purgatorius, part of an extinct group of primates called plesiadapiforms, first appears in the fossil record shortly after the extinction of non-avian dinosaurs. Some researchers have speculated over the years that primitive plesiadapiforms were terrestrial, and that primates moved into the tree canopy later. These ideas can still be found in some textbooks today.

    “The textbook that I am currently using in my biological anthropology courses still has an illustration of Purgatorius walking on the ground. Hopefully this study will change what students are learning about earliest primate evolution and will place Purgatorius in the trees where it rightfully belongs,” said Stephen Chester, the paper’s lead author. Chester, who conducted much of the research while at Yale University studying for his Ph.D., is an assistant professor at Brooklyn College, City University of New York. Chester is also a curatorial affiliate at the Yale Peabody Museum of Natural History.

    Until now, paleontologists had only the animal’s teeth and jaws to examine, which left much of its appearance and behavior a mystery. The identification of Purgatorius ankle bones, found in the same area as the teeth, gave researchers a better sense of how it lived.

    “The ankle bones have diagnostic features for mobility that are only present in those of primates and their close relatives today,” Chester said. “These unique features would have allowed an animal such as Purgatorius to rotate and adjust its feet accordingly to grab branches while moving through trees. In contrast, ground-dwelling mammals lack these features and are better suited for propelling themselves forward in a more restricted, fore-and-aft motion.”

    The research provides the oldest fossil evidence to date that arboreality played a key role in primate evolution. In essence, said the researchers, it implies that the divergence of primates from other mammals was not a dramatic event. Rather, primates developed subtle changes that made for easier navigation and better access to food in the trees.

    The research appears in the Jan. 19 online edition of the Proceedings of the National Academy of Sciences.

    The paper’s co-authors are Jonathan Bloch of the Florida Museum of Natural History at the University of Florida, who also contributed to the research as an Edward P. Bass Distinguished Visiting Environmental Scholar in the Yale Institute for Biospheric Studies; Doug Boyer of Duke University; and William Clemens of the University of California Museum of Paleontology, who collected fossils of Purgatorius and geological data over the past four decades with members of his field crews in Montana.

    See the full article here.

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