среда, 11 июля 2018 г.

NASA’s TESS Spacecraft Continues Testing Prior to First Observations

NASA . Tess Mission logo.

July 11, 2018

After a successful launch on April 18, 2018, NASA’s newest planet hunter, the Transiting Exoplanet Survey Satellite, is currently undergoing a series of commissioning tests before it begins searching for planets. The TESS team has reported that the spacecraft and cameras are in good health, and the spacecraft has successfully reached its final science orbit. The team continues to conduct tests in order to optimize spacecraft performance with a goal of beginning science at the end of July. 

Every new mission goes through a commissioning period of testing and adjustments before beginning science operations. This serves to test how the spacecraft and its instruments are performing and determines whether any changes need to be made before the mission starts observations.

Image above: An artist’s illustration of the Transiting Exoplanet Survey Satellite. Image Credits: NASA’s Goddard Space Flight Center.

TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA’s Ames Research Center in California’s Silicon Valley; the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts; MIT’s Lincoln Laboratory in Lexington, Massachusetts; and the Space Telescope Science Institute in Baltimore. More than a dozen universities, research institutes and observatories worldwide are participants in the mission.

For the latest updates on TESS, visit http://www.nasa.gov/tess

Image (mentioned), Text, Credits: NASA/Rob Garner/Goddard Space Flight Center/Claire Saravia.

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China Launches New Beidou Navigation Satellite

BeiDou Navigation Satellites System logo.

July 11, 2018

Image above: A file photo of Long March-3B rocket carrying two Beidou-3 satellites lifting.

On 10 July 2018, China launches a new navigation satellite into orbit from southwest China’s Xichang Satellite Launch Center, at 04:58 on Tuesday.

China Launches New Beidou Navigation Satellite

The “Beidou” navigation satellite, the 32nd among the Beidou navigation system line, was launched using one of China’s Long March-3A rockets.

BeiDou Navigation Satellite System

The satellite used in this operation was part of the Beidou-2 family, which represents the second generation of the system, and operates in a geosynchronous orbit.

Images, Text, Credits: CASC/CCTV+/China Daily.

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Captioned Image Spotlight (11 July 2018): Uplifted Blocks of…

Captioned Image Spotlight (11 July 2018): Uplifted Blocks of Light-Toned Layered Deposits

Aram Chaos lies within a 280 kilometer-diameter ancient impact crater in the Southern Highlands of Mars. Uplifted blocks of light-toned layers, composed largely of the iron-oxide hematite and water-altered silicates, indicate that this crater once held a lake.

Scientists suggest that these enormous flood channels were carved quickly within just weeks or months by catastrophic outflows of groundwater over 2.5 billion years ago from beneath Aram Chaos and nearby regions. Today dark (basaltic) dunes fill most of the low regions and the etched areas of the uplifted blocks obscure much of the original crater floor.

Aram Chaos is located near the headwaters of Ares Vallis, a large outflow channel system that extends about 1700 kilometers towards the northwest across the ancient cratered highlands before emptying into the Northern Lowlands at Chryse Planitia near the Mars Pathfinder landing site. 

NASA/JPL/University of Arizona (273 km above the surface, less than 1 km across)


What powers the most luminous galaxies?

Galaxy-galaxy interactions have long been known to influence galaxy evolution. They are commonplace events, and a large majority of galaxies show signs of interactions, including tidal tails or other morphological distortions. The most dramatic collisions trigger the galaxies to light up, especially in the infrared, and they are some of the most luminous objects in the sky. Their brightness allows them to be studied at cosmological distances, helping astronomers reconstruct activity in the early universe.

What powers the most luminous galaxies?
The colliding galaxy pair VV705. Astronomers have measured a set of merging galaxies to determine the relative
contributions to luminosity from star formation versus from accretion around the supermassive
black hole nucleus. For VV705, they find that nearly 75% of the luminosity comes
 from star formation [Credit: NASA/Hubble]

Two processes in particular are responsible for the enhanced radiation: bursts of star formation or the fueling of the supermassive black hole at a galaxy’s core (an active galactic nuclei—AGN). Although in principle these two processes are quite different and should be readily distinguishable (AGN, for example, produce much hotter ultraviolet and X-ray radiation), in practice the discriminating features can be faint and/or obscured by dust in the galaxies. Astronomers therefore often use the shape of the galaxy’s entire emission profile from the ultraviolet to the far infrared (its spectral energy distribution—SED), to diagnose what is going on. The dust that absorbs much of the radiation also re-radiates it at the longer infrared wavelengths and computer codes can model and unravel the numerous physical effects.

If bursts of star formation were responsible for powering luminous galaxies in the early universe, then many of today’s stars may have been formed in such events, but if AGN dominated, then there should have been more outflowing jets and fewer new stars. CfA astronomers Jeremy Dietrich, Aaron S. Weiner, Matt Ashby, Rafael Martinez-Galarza, Andres Ramos-Padilla, Howard Smith, Steve Willner, Andreas Zezas, and two colleagues analyzed twenty-four relatively nearby, luminous merging galaxies to see how often and to what extent AGN activity powered the energetics. They extracted the most meticulous SED information in thirty-three spectral bands from seven NASA missions for these galaxies, correcting for backgrounds, confusion, and other extraneous signals. They then used a new computational code to fit the shape of the SED and to derive the most likely value of the AGN contribution, as well to measure the star formation rate, the dust properties, and numerous other physical parameters. The scientists tested the reliability of the code by using it on simulations of galaxy mergers and found excellent agreement.

The astronomers find that the AGN contribution in their sample of galaxies reaches as high as ninety percent of the total luminosity; in other cases it falls below twenty percent and is possibly negligible. The team makes efforts to relate the magnitude of the AGN contribution to the merger stage of the system (from beginning to coalescing stages), but their modest sample size limited the generality of the conclusions. They are expanding their analysis to several hundred other mergers in order to strengthen the conclusions.

Source: Harvard-Smithsonian Center for Astrophysics [July 09, 2018]




Plasma-spewing quasar shines light on universe’s youth, early galaxy formation

Carnegie’s Eduardo Banados led a team that found a quasar with the brightest radio emission ever observed in the early universe, due to it spewing out a jet of extremely fast-moving material.

Plasma-spewing quasar shines light on universe's youth, early galaxy formation
Artist’s conception of a radio jet spewing out fast-moving material from the newly discovered
quasar, which formed within the first billion years of the universe’s existence
[Credit: Artwork by Robin Dienel, Carnegie Institution for Science]

Banados’ discovery was followed up by Emmanuel Momjian of the National Radio Astronomy Observatory, which allowed the team to see with unprecedented detail the jet shooting out of a quasar that formed within the universe’s first billion years of existence.

The findings, published in two papers in The Astrophysical Journal, will allow astronomers to better probe the universe’s youth during an important period of transition to its current state.

Quasars are comprised of enormous black holes accreting matter at the centers of massive galaxies. This newly discovered quasar, called PSO J352.4034-15.3373, is one of a rare breed that doesn’t just swallow matter into the black hole but also emits a jet of plasma traveling at speeds approaching that of light. This jet makes it extremely bright in the frequencies detected by radio telescopes. Although quasars were identified more than 50 years ago by their strong radio emissions, now we know that only about 10 percent of them are strong radio emitters.

What’s more, this newly discovered quasar’s light has been traveling nearly 13 billion of the universe’s 13.7 billion years to reach us here in Earth. P352-15 is the first quasar with clear evidence of radio jets seen within the first billion years of the universe’s history.

“There is a dearth of known strong radio emitters from the universe’s youth and this is the brightest radio quasar at that epoch by an order of magnitude,” Banados said.

“This is the most-detailed image yet of such a bright galaxy at this great distance,” Momjian added.

The Big Bang started the universe as a hot soup of extremely energetic particles that were rapidly expanding. As it expanded, it cooled and coalesced into neutral hydrogen gas, which left the universe dark, without any luminous sources, until gravity condensed matter into the first stars and galaxies. About 800 million years after the Big Bang, the energy released by these first galaxies caused the neutral hydrogen that was scattered throughout the universe to get excited and lose an electron, or ionize, a state that the gas has remained in since that time.

It’s highly unusual to find radio jet-emitting quasars such as this one from the period just after the universe’s lights came back on.

“The jet from this quasar could serve as an important calibration tool to help future projects penetrate the dark ages and perhaps reveal how the earliest galaxies came into being,” Banados concluded.

Source: Carnegie Institution for Science [July 09, 2018]




Charcoal: Major missing piece in the global carbon cycle

Most of the carbon resulting from wildfires and fossil fuel combustion is rapidly released into the atmosphere as carbon dioxide. Researchers at the University of Zurich have now shown that the leftover residue, so-called black carbon, can age for millennia on land and in rivers en route to the ocean, and thus constitutes a major long-term reservoir of organic carbon. The study adds a major missing piece to the puzzle of understanding the global carbon cycle.

Charcoal: Major missing piece in the global carbon cycle
Rivers transport black carbon from land to sea [Credit: Gabriela Santilli, ETH Zurich]

Due to its widespread occurrence and tendency to linger in the environment, black carbon may be one of the keys in predicting and mitigating global climate change. In wildfires, typically one third of the burned organic carbon is retained as black carbon residues rather than emitted as greenhouse gases.

Initially, black carbon remains stored in the soil and in lakes, and is then eroded from river banks and transported to the ocean. However, black carbon is not taken into account in global carbon budget warming simulations, because its role in the global carbon cycle is not well understood as a result of a lack of knowledge about fluxes, stocks, and residence times in the environment.

First worldwide assessment of black carbon river transport

“Our study is the first to address the flux of black carbon in sediments by rivers on a global scale. We found that a surprisingly large amount of black carbon is exported by rivers,” says lead author Alysha Coppola, a postdoctoral researcher in the Department of Geography at the University of Zurich (UZH).

Charcoal: Major missing piece in the global carbon cycle
Global black carbon cycle in large reservoirs [Credit: MELS/SIVIC, UZH]

The study includes some of the largest rivers worldwide, such as the Amazon, Congo, Brahmaputra, and major Arctic rivers. It is the first global river assessment of the radiocarbon age values and amount of black carbon transported as particles. The researchers found that the more total river sediment is transported by rivers to the coast, the more black carbon travels with it and is ultimately buried in ocean sediments, forming an important long-term sink for atmospheric carbon dioxide.

Black carbon can age in intermediate reservoirs

To gain an overview of the processes occurring in the world’s rivers, the UZH researchers teamed up with colleagues from ETH Zurich, and the US-based Global Rivers Observatory at the Woods Hole Oceanographic Institution and the Woods Hole Research Center.

They discovered that the black carbon pathway from land to ocean is mainly shaped by erosion in river drainage basins. Surprisingly, they found that some black carbon can be stored for thousands of years before being exported to the ocean via rivers. This insight is new, since it was previously always assumed that after a fire, the remaining black carbon was quickly eroded by wind and water.

However, the authors found that black carbon does not always originate from recent wildfires, but could be up to 17,000 years old, particularly in the Arctic. “This explains the mystery as to why black carbon is continuously present in river waters, regardless of wildfire history. We found that black carbon can age in intermediate reservoirs that act as holding pools before being exported to the ocean,” says Alysha Coppola.

The study is published in Nature Geoscience.

Source: University of Zurich [July 09, 2018]




Long term use of some pesticides is killing off dung beetle populations

New research led by scientists at the University of Bristol has uncovered that long-term use of some pesticides to treat cattle for parasites is having a significantly detrimental effect on the dung beetle population.

Long term use of some pesticides is killing off dung beetle populations
Credit: University of Bristol

Researchers studied 24 cattle farms across south west England and found that farms that used certain pesticides had fewer species of dung beetle.

Dr Bryony Sands, from the University’s School of Biological Sciences, who led the research, said: “Dung beetles recycle dung pats on pastures, bringing the nutrients back into the soil and ensuring the pastures are fertile.

“Damage to dung beetle populations is therefore concerning, and could result in economic loss for farmers.”

This is the first landscape-scale study to show that long-term use of the pesticides has negative impacts on dung beetle populations on farms.

Professor Richard Wall, a co-author on the study, first discovered 30 years ago that pesticide residues in dung could kill these important beetles.

Dr Sands added: “It is now clear that long-term use of these pesticides could cause declines in beetle biodiversity on a large scale.”

The study, published in the journal Agriculture, Ecosystems & Environment, also found that pesticides known as synthetic pyrethroids were less damaging to dung beetles than macrocyclic lactone pesticides.

These are generally thought of as a safer alternative for farmers who want to protect biodiversity on their farms.

Dr Sands said: “Although these chemicals do appear to be less damaging, farms that used them still had a smaller proportion of certain dung beetles, which are very important in removing dung from pastures by burying it.

“The conservation of dung beetles is vital for the health and future sustainability of our farmland.

“Biodiversity losses such as these could result in loss of the services dung beetles provide to our ecosystems: dung decomposition, nutrient cycling, soil fertility and the preventing disease transmission.”

Dr Sands and her colleagues hope the findings of the study will go some way to inform farmers about the negative impacts of these pesticides – some of which now have specific warnings labels on the bottles.

Source: University of Bristol [July 09, 2018]




The sea anemone, an animal that hides its complexity well

Despite its apparent simplicity — a tube-like body topped with tentacles -, the sea anemone is actually a highly complex creature. Scientists from the Institut Pasteur, in collaboration with the CNRS, have just discovered over a hundred different cell types in this small marine invertebrate as well as incredible neuronal diversity. This surprising complexity was revealed when the researchers built a real cell atlas of the animal. Their findings, which will add to discussions on how cells have diversified and developed into organs during evolution, have been published in the journal Cell.

The sea anemone, an animal that hides its complexity well
(Left): a sea anemone, Nematostella vectensis. (Center) Living (green) and dead (red) cells isolated after
dissociation. (Right) N. vectensis neurons revealed by the specific expression of a transgenic marker
[Credit: © Institut Pasteur]

The sea anemone Nematostella vectensis provides a perfect model for researchers — apart from its stinging tentacles perhaps. It is a small marine invertebrate that is easy to keep in the laboratory and whose genome is simple enough to study its workings and close enough to that of humans for conclusions to be drawn. “When the sea anemone genome was sequenced in 2007, scientists discovered that it was very similar to the human genome, both in terms of the number of genes (roughly 20,000) and its organization, explains Heather Marlow, a specialist in developmental biology in the (Epi)genomics of Animal Development Unit at the Institut Pasteur and the main author of this study. These similarities make the sea anemone an ideal model for studying the animal genome and understanding interactions existing between genes.” It also has another advantage — its strategic position in the tree of life. The cnidaria branch that anemones belong to separated from the bilateria branch, in other words from most other animals, including humans, over 600 million years ago. “The anemone can therefore also help us to understand the origin and evolution of the multiple cell types making up the bodies and organs of animals, and particularly their nervous systems,” sums up Heather Marlow.

To try and understand a little more about sea anemones — and consequently about the whole animal kingdom -, Heather Marlow’s team decided to examine this cnidarian, cell by cell. Thanks to an innovative technique, the animal’s tiny cells — that measure no more than 1 micron in diameter — were isolated one by one, and their RNA analyzed. As although chromosomal DNA contains all genes, RNA shows those that are active. “The development of genome approaches at single-cell level can be used to accurately list the different cell types and also identify the genes responsible for the function of each of these cells,” explains Heather Marlow. In total, and unexpectedly, over a hundred different cell types were identified, grouped into eight main cell families (muscle, digestive, neuronal, epidermal, etc.). And one of the greatest surprises of this research concerns the nervous system. Close to thirty different types of neurons — peptidergic, glutamatergic or even insulinergic — were identified, revealing a relatively complex nervous and sensory system.

This research should therefore help evolution specialists to establish the common ancestor of cnidaria (anemones) on the one hand and bilateria (humans) on the other. Undoubtedly this ancestor already had some level of cell complexity. In addition, even though the sea anemone appears to be very different from us, it reveals the fundamental rules that today enable its cells, and our own, to perform so many different functions. “The cell is the basic element making up living beings.” By defining how the information coded by the genome determines the identity of each cell, we hope to uncover the mechanisms conserved by all animals that are essential for their development and homeostasis ,” concludes Heather Marlow.

Source: Institut Pasteur [July 09, 2018]




Cross species transfer of genes has driven evolution

Far from just being the product of our parents, University of Adelaide scientists have shown that widespread transfer of genes between species has radically changed the genomes of today’s mammals, and been an important driver of evolution.

Cross species transfer of genes has driven evolution
A graphic representation of the BovB element which shows how it has appeared in species that are
wide apart on the evolutionary tree — for example sea urchins and elephants, cows and snakes
[Credit: University of Adelaide]

In the world’s largest study of so-called “jumping genes”, the researchers have traced two particular jumping genes across 759 species of plants, animals and fungi. These jumping genes are actually small pieces of DNA that can copy themselves throughout a genome and are known as transposable elements.

They have found that cross-species transfers, even between plants and animals, have occurred frequently throughout evolution.

Both of the transposable elements they traced – L1 and BovB – entered mammals as foreign DNA. This is the first time anyone has shown that the L1 element, important in humans, has jumped between species.

“Jumping genes, properly called retrotransposons, copy and paste themselves around genomes, and in genomes of other species. How they do this is not yet known although insects like ticks or mosquitoes or possibly viruses may be involved – it’s still a big puzzle,” says project leader Professor David Adelson, Director of the University of Adelaide’s Bioinformatics Hub.

“This process is called horizontal transfer, differing from the normal parent-offspring transfer, and it’s had an enormous impact on mammalian evolution.”

For example, Professor Adelson says, 25% of the genome of cows and sheep is derived from jumping genes.

“Think of a jumping gene as a parasite,” says Professor Adelson. “What’s in the DNA is not so important – it’s the fact that they introduce themselves into other genomes and cause disruption of genes and how they are regulated.”

Published in the journal Genome Biology, in collaboration with the South Australian Museum, the researchers found horizontal gene transfer was much more widespread than had been thought.

“L1 elements were thought to be inherited only from parent to offspring,” says lead author Dr Atma Ivancevic, postdoctoral researcher in the University of Adelaide’s Medical School. “Most studies have only looked at a handful of species and found no evidence of transfer. We looked at as many species as we could.”

L1 elements in humans have been associated with cancer and neurological disorders. The researchers say that understanding the inheritance of this element is important for understanding the evolution of diseases.

The researchers found L1s are abundant in plants and animals, although only appearing sporadically in fungi. But the most surprising result was the lack of L1s in two key mammal species – the Australian monotremes (platypus and echidna) – showing that the gene entered the mammalian evolutionary pathway after the divergence from monotremes.

“We think the entry of L1s into the mammalian genome was a key driver of the rapid evolution of mammals over the past 100 million years,” says Professor Adelson.

The team also looked at the transfer of BovB elements between species. BovB is a much younger jumping gene: it was first discovered in cows, but has since been shown to jump between a bizarre array of animals including reptiles, elephants and marsupials. Earlier research, led by Professor Adelson, found that ticks were the most likely facilitators of cross-species BovB transfer.

The new research extended the analysis to find that BovB has jumped even more widely than previously anticipated. BovB has transferred at least twice between frogs and bats, and new potential vector species include bed bugs, leeches and locusts.

The team believes that studying insect species will help find more evidence of cross-species transfer. They also aim to study other jumping genes and explore the possibility of aquatic vectors, such as sea worms and nematodes.

“Even though our recent work involved the analysis of genomes from over 750 species, we have only begun to scratch the surface of horizontal gene transfer,” says Professor Adelson. “There are many more species to investigate and other types of jumping genes.”

Source: University of Adelaide [July 09, 2018]




Artery Alert System Holistic medical practitioners may tell…

Artery Alert System

Holistic medical practitioners may tell people, in a metaphorical sense, to ‘listen to their bodies’. But, with the development of smart implants, biomedical engineers may one day make this literally possible. Take this smart stent (pictured) for example. It’s designed to be placed inside a person’s artery, to monitor blood flow, and to ‘talk’ wirelessly to an external reader providing continuous updates. Many patients who receive normal arterial stents – to treat narrowing of the blood vessels caused by the build up of cholesterol – are at risk of post-surgical re-narrowing (restenosis), which can ultimately lead to a blockage and an unexpected heart attack or stroke. The new smart stent, which has so far only been tested in pigs, would essentially function just like a normal stent but have the added advantage of being able to alert a patient or doctor to an impending deadly narrowing event.

Written by Ruth Williams

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HiPOD (11 July 2018): Fractures on Pavonis Mons   – This…

HiPOD (11 July 2018): Fractures on Pavonis Mons

   – This observation was suggested by students at the Mars Academy in Brazil. Here is their original rationale: “This “stressed-out” region of the northeastern slopes of Pavonis Mons contains multiple sets of sub-parallel faults, with down-thrown blocks indicating tensional stretching of the crustal layers. We wish to examine a couple of these features in detail using HiRISE images, in order to address several questions, including: Do the sizes/extent of these fractures correlate with slope breaks or apparent mineralogical changes? Are these tectonic/volcanic features, or could they be more reflective of surface processes? Are the fractures topographic lows (i.e., ditches) that have accumulated mass wasting products and/or demonstrate over-printing signs of fluvial erosion?”

NASA/JPL/University of Arizona (258 km above the surface. Black and white is less than 5 km across; enhanced color is less than 1 km.)


Following the fresh water: Fingerprint of ancient abrupt climate change found in Arctic

A research team led by Woods Hole Oceanographic Institution (WHOI) found the fingerprint of a massive flood of fresh water in the western Arctic, thought to be the cause of an ancient cold snap that began around 13,000 years ago.

Following the fresh water: fingerprint of ancient abrupt climate change found in Arctic
In 2013, a team of researchers set sail to the eastern Beaufort Sea in search of evidence for the flood near where the
Mackenzie River enters the Arctic Ocean, forming the border between Canada’s Yukon and Northwest territories.
From aboard the US Coast Guard Cutter Healy in ice-covered waters, the team gathered sediment cores from
along the continental slope east of the Mackenzie River. Above, the piston corer is shown in horizontal
position, with the gravity corer hanging vertically ready to be launched
[Credit: Lloyd Keigwin, Woods Hole Oceanographic Institution]

“This abrupt climate change — known as the Younger Dryas — ended more than 1,000 years of warming,” explains Lloyd Keigwin, an oceanographer at WHOI and lead author of the paper published in the journal Nature Geocscience.

The cause of the cooling event, which is named after a flower (Dryas octopetala) that flourished in the cold conditions in Europe throughout the time, has remained a mystery and a source of debate for decades.

Many researchers believed the source was a huge influx of freshwater from melting ice sheets and glaciers that gushed into the North Atlantic, disrupting the deep-water circulation system — Atlantic Meridional Overturning Circulation (AMOC) — that transports warmer waters and releases heat to the atmosphere. However, geologic evidence tracing its exact path had been lacking.

In 2013, a team of researchers from WHOI, Scripps Institution of Oceanography at the University of California San Diego, and Oregon State University, set sail to the eastern Beaufort Sea in search of evidence for the flood near where the Mackenzie River enters the Arctic Ocean, forming the border between Canada’s Yukon and Northwest territories. From aboard the U.S. Coast Guard Cutter Healy, the team gathered sediment cores from along the continental slope east of the Mackenzie River. After analyzing the shells of fossil plankton found in the sediment cores, they found the long sought-after geochemical signal from the flood.

Following the fresh water: fingerprint of ancient abrupt climate change found in Arctic
When it comes to regulating global climate, the circulation of the Atlantic Ocean plays a key role. The Gulf Stream
carries warm, salty water to the Labrador Sea and the Nordic Seas, where it releases heat to the atmosphere and
warms Western Europe. The cooler, denser water then sinks to great depths to propel currents around the world
and eventually circulate water back up to the Gulf Stream. Influxes of fresh water can disrupt the deep-water
system resulting in impacts on climate, such as what occurred around 13,000 years ago with the Younger Dryas
cooling event. Recent research found the system hasn’t been running at peak strength since the mid-1800s
and is currently at its weakest point in the past 1,600 years. Continued weakening
could disrupt weather patterns from the U.S. and Europe to the African Sahel
[Credit: Natalie Renier, Woods Hole Oceanographic Institution]

“The signature of oxygen isotopes recorded in foraminifera shells preserved in the sediment allowed us to fingerprint the source of the glacial lake discharge down the MacKenzie River 13,000 years ago,” said co-principal investigator Neal Driscoll, a professor of geology and geophysics at Scripps Oceanography. “Radiocarbon dating on the shells provided the age constraints. Circulation models for the Arctic Ocean reveal that low-salinity surface water is efficiently transported to the North Atlantic. How exciting it is when the pieces of a more than 100-year puzzle come together.”

Next steps in future research, Keigwin says, will be for scientists to answer remaining questions about the quantity of fresh water delivered to the North Atlantic preceding the Younger Dryas event and over how long of a period of time.

“Events like this are really important, and we have to understand them better,” adds Keigwin. “In the long run, I think the findings from this paper will stimulate more research on how much fresh water is really necessary to cause a change in the system and weakening of the AMOC. It certainly calls further attention to the warming we’re seeing in the Arctic today, and the accelerated melting of Greenland ice.”

Earlier this year, a paper by researchers at the University College London and WHOI found evidence that the AMOC hasn’t been running at peak strength since the mid-1800s and is currently at its weakest point in the past 1,600 years. Continued weakening could disrupt weather patterns from the U.S. and Europe to the African Sahel.

Source: Woods Hole Oceanographic Institution [July 09, 2018]




Oxygen levels on early Earth rose, fell several times before great oxidation even

Earth’s oxygen levels rose and fell more than once hundreds of millions of years before the planetwide success of the Great Oxidation Event about 2.4 billion years ago, new research from the University of Washington shows.

Oxygen levels on early Earth rose, fell several times before great oxidation even
The Jeerinah Formation in Western Australia, where a UW-led team found a sudden shift in nitrogen isotopes. “Nitrogen
 isotopes tell a story about oxygenation of the surface ocean, and this oxygenation spans hundreds of kilometers
across a marine basin and lasts for somewhere less than 50 million years,” said lead author Matt Koehler
[Credit: Roger Buick/University of Washington]

The evidence comes from a new study that indicates a second and much earlier “whiff” of oxygen in Earth’s distant past — in the atmosphere and on the surface of a large stretch of ocean — showing that the oxygenation of the Earth was a complex process of repeated trying and failing over a vast stretch of time.

The finding also may have implications in the search for life beyond Earth. Coming years will bring powerful new ground- and space-based telescopes able to analyze the atmospheres of distant planets. This work could help keep astronomers from unduly ruling out “false negatives,” or inhabited planets that may not at first appear to be so due to undetectable oxygen levels.

“The production and destruction of oxygen in the ocean and atmosphere over time was a war with no evidence of a clear winner, until the Great Oxidation Event,” said Matt Koehler, a UW doctoral student in Earth and space sciences and lead author of a new paper published in the Proceedings of the National Academy of Sciences.

“These transient oxygenation events were battles in the war, when the balance tipped more in favor of oxygenation.”

In 2007, co-author Roger Buick, UW professor of Earth and space sciences, was part of an international team of scientists that found evidence of an episode — a “whiff” — of oxygen some 50 million to 100 million years before the Great Oxidation Event. This they learned by drilling deep into sedimentary rock of the Mount McRae Shale in Western Australia and analyzing the samples for the trace metals molybdenum and rhenium, accumulation of which is dependent on oxygen in the environment.

Now, a team led by Koehler has confirmed a second such appearance of oxygen in Earth’s past, this time roughly 150 million years earlier — or about 2.66 billion years ago — and lasting for less than 50 million years. For this work they used two different proxies for oxygen — nitrogen isotopes and the element selenium — substances that, each in its way, also tell of the presence of oxygen.

“What we have in this paper is another detection, at high resolution, of a transient whiff of oxygen,” said Koehler. “Nitrogen isotopes tell a story about oxygenation of the surface ocean, and this oxygenation spans hundreds of kilometers across a marine basin and lasts for somewhere less than 50 million years.”

The team analyzed drill samples taken by Buick in 2012 at another site in the northwestern part of Western Australia called the Jeerinah Formation.

Oxygen levels on early Earth rose, fell several times before great oxidation even
Impact spherules (white spheres) from an asteroid colliding with Earth ~2.63 billion years ago deposited in a formation
used in this study [Credit: Katherine French (Massachusetts Institute of Technology, Cambridge, MA]

The researchers drilled two cores about 300 kilometers apart but through the same sedimentary rocks — one core samples sediments deposited in shallower waters, and the other samples sediments from deeper waters. Analyzing successive layers in the rocks years shows, Buick said, a “stepwise” change in nitrogen isotopes “and then back again to zero. This can only be interpreted as meaning that there is oxygen in the environment. It’s really cool — and it’s sudden.”

The nitrogen isotopes reveal the activity of certain marine microorganisms that use oxygen to form nitrate, and other microorganisms that use this nitrate for energy. The data collected from nitrogen isotopes sample the surface of the ocean, while selenium suggests oxygen in the air of ancient Earth. Koehler said the deep ocean was likely anoxic, or without oxygen, at the time.

The team found plentiful selenium in the shallow hole only, meaning that it came from the nearby land, not making it to deeper water. Selenium is held in sulfur minerals on land; higher atmospheric oxygen would cause more selenium to be leached from the land through oxidative weathering — “the rusting of rocks,” Buick said — and transported to sea.

“That selenium then accumulates in ocean sediments,” Koehler said. “So when we measure a spike in selenium abundances in ocean sediments, it could mean there was a temporary increase in atmospheric oxygen.”

The finding, Buick and Koehler said, also has relevance for detecting life on exoplanets, or those beyond the solar system.

“One of the strongest atmospheric biosignatures is thought to be oxygen, but this study confirms that during a planet’s transition to becoming permanently oxygenated, its surface environments may be oxic for intervals of only a few million years and then slip back into anoxia,” Buick said.

“So, if you fail to detect oxygen in a planet’s atmosphere, that doesn’t mean that the planet is uninhabited or even that it lacks photosynthetic life. Merely that it hasn’t built up enough sources of oxygen to overwhelm the ‘sinks’ for any longer than a short interval.

“In other words, lack of oxygen can easily be a ‘false negative’ for life.”

Koehler added: “You could be looking at a planet and not see any oxygen — but it could be teeming with microbial life.”

Author: Peter Kelley | Source: University of Washington [July 09, 2018]




Scientists discover the world’s oldest colours in the geological record

Scientists from The Australian National University (ANU) and overseas have discovered the oldest colours in the geological record, 1.1 billion-year-old bright pink pigments extracted from rocks deep beneath the Sahara desert in Africa.

Scientists discover the world's oldest colours in the geological record
Biogeochemistry Lab Manager Janet Hope from the ANU Research School of Earth Sciences
holds a vial of pink colored porphyrins representing the oldest intact pigments in the world
[Credit: The Australian National University]

Dr Nur Gueneli from ANU said the pigments taken from marine black shales of the Taoudeni Basin in Mauritania, West Africa, were more than half a billion years older than previous pigment discoveries. Dr Gueneli discovered the molecules as part of her PhD studies.

“The bright pink pigments are the molecular fossils of chlorophyll that were produced by ancient photosynthetic organisms inhabiting an ancient ocean that has long since vanished,” said Dr Gueneli from the ANU Research School of Earth Sciences.

The fossils range from blood red to deep purple in their concentrated form, and bright pink when diluted.

ANU led the research with support from Geoscience Australia and researchers in the United States and Japan.

The researchers crushed the billion-year-old rocks to powder, before extracting and analysing molecules of ancient organisms from them.

“The precise analysis of the ancient pigments confirmed that tiny cyanobacteria dominated the base of the food chain in the oceans a billion years ago, which helps to explain why animals did not exist at the time,” Dr Gueneli said.

Senior lead researcher Associate Professor Jochen Brocks from ANU said that the emergence of large, active organisms was likely to have been restrained by a limited supply of larger food particles, such as algae.

“Algae, although still microscopic, are a thousand times larger in volume than cyanobacteria, and are a much richer food source,” said Dr Brocks from the ANU Research School of Earth Sciences.

“The cyanobacterial oceans started to vanish about 650 million years ago, when algae began to rapidly spread to provide the burst of energy needed for the evolution of complex ecosystems, where large animals, including humans, could thrive on Earth.”

The research is published in the Proceedings of the National Academy of Sciences.

Source: Australian National University [July 09, 2018]




Bale monkeys living in different areas have very different DNA

Bale monkey’s that live in continuous bamboo forests have different mitochondrial DNA to Bale monkeys living in fragmented forests, according to a study published in the open access journal, BMC Evolutionary Biology.

Bale monkeys living in different areas have very different DNA
Bale monkey from Kokosa forest fragment [Credit: Addisu Mekonnen]

Dr Addisu Mekonnen and colleagues at The University of Oslo, Norway, looked at the genetic diversity of the two populations of Bale monkeys. Analysis of mitochondrial DNA suggested strong genetic differences between the Bale monkeys who lived in continuous forests or fragmented forests. The researchers found that the populations of Bale monkeys were so different from each other that the Bale monkeys from fragmented forests were more similar to vervets and grivets than Bale monkeys from continuous forests.

Dr Addisu Mekonnen, corresponding author of the study, explains: “Remarkably, our phylogenetic analysis showed that Bale monkeys in fragmented forests are more closely related to their sister species, vervets and grivets, than Bale Monkeys from continuous forests. This suggests that hybridization had taken place between Bale monkeys from fragmented forests and vervet and grivet monkeys, but not with bale monkeys in continuous forests. This hybridization could be due to habitat fragmentation and close proximity to similar monkeys.”

The authors explain that Bale monkeys, similar to giant pandas and bamboo lemurs, are particularly vulnerable to changes in their habitat as they rely heavily on bamboo and inhabit a small geographic area and are assumed to be less flexible at adapting to a changing environment than a species who don’t rely so heavily on one food source and one area.

Bale monkeys living in different areas have very different DNA
Bale monkey from Odobullu continuous forest of the Bale Mountains [Credit: Addisu Mekonnen]

Bale Monkeys are severely affected by habitat fragmentation and have the most restricted range of all green monkeys. The results of this study suggest that the altered gene pool of Bale Monkeys in Fragmented Forests has made them less dependent on bamboo lifestyle. “Similar to other bamboo specialist mammals, such as giant pandas and bamboo lemurs, Bale monkeys are currently at high risk of extinction in the wild because of habitat alteration. They are classified as a vulnerable species by the IUCN Red List of Threatened Species with a general trend of population decline.”

Bale monkeys are one of the least studied African primates so collecting baseline data on population genetic structure and evolutionary history are crucial for assessing their conservation status and protecting them. In terms of advising conservation, because of two isolated populations (with one cluster consisting of hybrids) 2 separate management structures should be defined to preserve the unique genetic diversity of the species and the evolutionary potential. For the CF population they recommend special protection as these represent what are thought to be typical Bale monkeys.

Improved protection from logging of bamboo could help them. For the FF population they recommend connecting forest fragments to increase gene flow between isolated groups.

Faecal samples were collected from May to December 2013 at three localities in Continuous Forest and nine localities in Fragmented Forest. Mitochondrial DNA was extracted from these samples and analysed.

The authors note that the genetic analysis should be interpreted with caution because they used a single and maternally inherited mitochondrial DNA locus that tells only the maternal history. The researchers explain that further future research focusing on bi-parentally and paternally inherited genetic markers, as well as morphological and ecological studies is needed to further understand the evolutionary history of this unusual and rare species.

Source: BioMed Central [July 09, 2018]




Mosaics provide clues on life in an ancient Galilean Jewish village

Recent discoveries by a team of specialists and students at Huqoq in Israel’s Galilee, led by University of North Carolina at Chapel Hill professor Jodi Magness, shed new light on the life and culture of an ancient Jewish village. The discoveries indicate villagers flourished under early fifth century Christian rule, contradicting a widespread view that Jewish settlement in the region declined during that period. The large size and elaborate interior decoration of the Huqoq synagogue point to an unexpected level of prosperity.

Mosaics provide clues on life in an ancient Galilean Jewish village
Spies Panel from UNC-Chapel Hill professor Dr. Jodi Magness’ 2018 Huqoq excavation
 [Credit: Jim Haberman]

“The mosaics decorating the floor of the Huqoq synagogue revolutionize our understanding of Judaism in this period,” said Magness. “Ancient Jewish art is often thought to be aniconic, or lacking images. But these mosaics, colorful and filled with figured scenes, attest to a rich visual culture as well as to the dynamism and diversity of Judaism in the Late Roman and Byzantine periods.”

The first mosaics in the Huqoq synagogue were discovered by Magness’ team in 2012. Since then, Magness, director of the Huqoq excavations and Kenan Distinguished Professor of Early Judaism in the department of religious studies in Carolina’s College of Arts & Sciences, assisted by Shua Kisilevitz of the Israel Antiquities Authority and Tel Aviv University have uncovered additional mosaics every summer. This year, the team’s specialists and students focused their efforts on a series of mosaic panels in the north aisle. Magness said this series is part of the richest, most diverse collection of mosaics ever found in an ancient synagogue.

Along the north aisle, mosaics are divided into two rows of panels containing figures and objects with Hebrew inscriptions. One panel labeled “a pole between two” depicts a biblical scene from Numbers 13:23. The images show two spies sent by Moses to explore Canaan carrying a pole with a cluster of grapes. Another panel referencing Isaiah 11:6 includes the inscription “a small child shall lead them.” The panel shows a youth leading an animal on a rope. A fragmentary Hebrew inscription concluding with the phrase “Amen selah,” meaning “Amen forever,” was uncovered at the north end of the east aisle.

During this eighth dig, the team also continued to expose a rare discovery in ancient synagogues: columns covered in colorful, painted plaster still intact after nearly 1,600 years.

The mosaics have been removed from the site for conservation and the excavated areas have been backfilled. Excavations are scheduled to continue in the summer of 2019. Additional information and updates can be found at the project’s website: http://www.huqoq.org.

Mosaics uncovered by this project include:

2012: Samson and the foxes

2013: Samson carrying the gate of Gaza on his shoulders

2013, 2014 and 2015: a Hebrew inscription surrounded by human figures, animals and mythological creatures including cupids; and the first non-biblical story ever found decorating an ancient synagogue — perhaps the legendary meeting between Alexander the Great and the Jewish high priest

2016: Noah’s Ark; the parting of the Red Sea showing Pharaoh’s soldiers being swallowed by giant fish

2017: a Helios-zodiac cycle; Jonah being swallowed by three successive fish; the building of the Tower of Babel

Source: University of North Carolina at Chapel Hill [July 09, 2018]




Researchers discover the oldest giant dinosaur species that inhabited the Earth

Scientists presented Ingentia prima, the first giant dinosaur that inhabited the Planet more than 200 million years ago. It exceeds three times the size of the largest Triassic dinosaurs known to date. The discovery was made at the Balde de Leyes deposit, southeast of the province of San Juan.

Researchers discover the oldest giant dinosaur species that inhabited the Earth
The Balde de Leyes site was first discovered in 2001 and started unearthing bone fragments in 2014
[Credit: Jorge A. González]

Dinosaurs were not always giants. The evolutionary history took millions of years for some species to double the weight of a current elephant and reach between eight and ten meters in length, but that time was much less than was believed: hence the great importance of the finding of Ingentia prima, which would have had a body mass of up to ten tons.

Dr. Cecilia Apaldetti, researcher at the Institute and Museum of Natural Sciences of the University of San Juan (IMCN) and CONICET, told the Agencia CTyS-UNLaM that “this new species shows a strategy of growth unknown until now and indicates that the origin of gigantism came much earlier than previously thought”.

“Before this discovery, gigantism was considered to have emerged during the Jurassic period, approximately 180 million years ago, but Ingentia prima lived at the end of the Triassic, between 210 and 205 million years ago”, specified the study’s principal author which was published in the prestigious journal Nature Ecology & Evolution.

Researchers discover the oldest giant dinosaur species that inhabited the Earth
Researchers admit the discovery of the giant dinosaur was a surprise
[Credit: Jorge A. González]

Paleontologist Ricardo Martinez, co-author of the publication and also researcher at IMCN, commented, “the name of this new species, ‘Ingentia’, refers to its colossal size, while ‘prima’ indicates that it is the first known giant to today on the Planet”.

“Giant, above all, for his moment in evolution”, remarked Apaldetti. He added: “We see in Ingentia prima the origin of gigantism, the first steps so that, more than 100 million years later, sauropods of up to 70 tons could come into existence like those that lived in Patagonia”.

The largest quadruped and long-necked herbivorous dinosaurs of record, such as Patagotitan, Puertasaurus and Argentinosaurus, derived from the Triassic sauropodomorphs as Ingentia prima; what was not known, until now, is that gigantism had already developed more than 200 million years ago.

Researchers discover the oldest giant dinosaur species that inhabited the Earth
Several bone fragments from the neck, tail, fore and hind legs have been found
[Credit: Jorge A. González]

The researcher at the Institute of Research in Paleo biology and Geology of the National University of Río Negro (IIPG-CONICET, UNRN) Ignacio Cerda analyzed the bones of this new species to understand how it was growing in life: “Just as growth seasons can be observed in a tree, the bony cuts in Ingentia prima show that it had cyclical, seasonal growth, but what is striking is that the type of tissue that was deposited in the bones during these periods of growth is different from the other sauropods we knew so far. “

“This fabric allowed him to achieve a very rapid growth”, assumed Cerda. And he explained: “To differentiate the form of growth that it had, we can make an analogy with a car that goes at a continuous high speed, at 100 kilometers per hour, imagining that this is how the sauródopos grew, while Ingentia prima made a part of the trek to 300 kilometers per hour, during the seasons of growth, to stop later during the seasons of winter or shortage and, later, to grow back to 300 kilometers per hour”.

Cyclic growth was common among the primitive sauropodomorphs of the Triassic, but no other species exceeded three meters in length and three tons of body mass. “The difference is that the tissue formed in the rest of these sauropodomorphs did not have such a rapid deposition speed”, said Dr. Cerda, who also works at the Carlos Ameghino Provincial Museum in Cipolletti.

Researchers discover the oldest giant dinosaur species that inhabited the Earth
Ingenia prima weighed around the same as two or three African elephants
[Credit: Jorge A. González]

Although you can see these growth rings in the same way as trees, it is not possible to know the exact age at which this specimen died. “In this case, it is difficult to trace the continuity of the concentric lines, but we estimate that he was a subadult individual, who was still maturing, so he could have grown a little more”, commented the IIPG-CONICET researcher.

The first giant in the world already has a family

Beyond the fact that Ingentia prima, the first dinosaur to reach gigantism, was far from reaching the 70 tons that had the most giant sauropods of the late Cretaceous, the speed of bone tissue accumulation was not only superior to the species of its epoch, but also greater than that of the largest giants that inhabited Patagonia.

Dr. Diego Pol of the Egidio Feruglio Museum (MEF) and of CONICET, who was one of the authors of the study that presented the largest dinosaur of which one has knowledge -Patagotitan-, also participated in the analysis of Ingentia prima to determine its relations of kinship with other previously known species.

Researchers discover the oldest giant dinosaur species that inhabited the Earth
Reconstruction of the sauropodomorph dinosaur Ingentia prima showing an improved avian-like
respiratory system with developed cervical air sacs (green structure). Lungs in brown colour
[Credit: Jorge A. González]

“What we demonstrate is the existence of a family that had not been recognized, of which Ingentia prima is a part, a species of South Africa and another of South America, which is further evidence of the close connection that existed between both continents at that time when everyone made up a supercontinent called Pangea”, Dr. Pol told to the Agencia CTyS-UNLaM.

The MEF researcher assured that “the discovery of this new species of the Triassic has a great implication for the evolutionary history, because it corresponds to the first stage of the dinosaurs and it is important to know that, at the moment they began to expand by the world, the first gigantic species have already appeared”.

“This finding gives a new look at the magnitude of the evolutionary explosion that the dinosaurs had”, said paleontologist Pol. He added: “This evolutionary explosion was so great that it explains the success the dinosaurs had during the rest of their era”.

Researchers discover the oldest giant dinosaur species that inhabited the Earth
Reconstruction of Ingentia prima from the Late Triassic (205- 210Ma) of Argentina.
Total length 8-10 metres [Credit: Jorge A. González]

Giantism is an evolutionary survival strategy, especially for herbivorous animals, because size is a form of defense against predators. “In order to achieve gigantism, Ingentia prima also had to adapt its physiology and develop an efficient food apparatus to be able to cover the energy requirement of an animal of that size,” specified Pol.

The director of the IMCN Oscar Alcober stressed that this new species had another evolutionary feature that also would have favored its gigantism: “Cavities are observed in the bones of Ingentia, which lightened the weight of this species and would have favored it to acquire a larger size bodily”.

“These pneumatic cavities indicate that this new species had highly developed air sacs and a very efficient breathing system, similar to what happens in modern birds, which also helped it to keep its body cool despite its large size”, paleontologist Cecilia Apaldetti asserted.

Researchers discover the oldest giant dinosaur species that inhabited the Earth
Dr. Cecilia Apaldetti with an illustration of Ingentia prima
[Credit: Jorge A. González]

Ingentia prima allows us to recognize that gigantism and diverse evolutionary patterns originated during the first stage of the emergence of dinosaurs. The Triassic period ended about 200 million years ago, at which time there was a great extinction, although the sauropods continued with their existence throughout the Jurassic and until the end of the Cretaceous, when they died, 65 million years ago, all species of non-avian dinosaurs.

An extraordinary site from the end of the Triassic

The researchers of the Institute and Museum of Natural Sciences of the University of San Juan have the privilege of having in their province the famous site of Ischigualasto, one of the most important of the Triassic world. As if this were not enough, a few years ago, they discovered the extraordinary location of the Bucket of Laws in the Marayes basin, with which they can complete the puzzle of the early days of the dinosaurs.

Dr. Ricardo Martinez told the Agencia CTyS-UNLaM that “Bucket of Laws is a new site with a whole unknown fauna until now, while in Ischigualasto we have a succession of Triassic rocks between 250 and 213 million years old, in this new site we have from the 235 million years until the end of the Triassic and, even, the first stage of the Jurassic Period”.

In Balde de Leyes, in addition to discovering the giant herbivore Ingentia prima, they have also found and named the carnivore Lucianovenator bonoi. “Lucianovenator and Ingentia are from the same period”, said Martínez. And he analyzed: “Although Lucianavenator was not very big, because it measured a meter and a half, it was a bug of care and could have fed on Ingentia, perhaps making a group attack or taking advantage of any of this giants was injured or in old age”.

“However, we have also found teeth that belong to a carnivore with a skull of between 60 and 80 centimeters, so we know that there was a larger predator circling there and that it could have been a theropod or some predecessor of the crocodiles “, added the researcher.

With each new campaign, more species and groups continue to appear. Regarding what the environment was like at that time, Martínez said: “The temperature was higher and the weather varied a lot between the seasons; meanwhile, although we have not found fossil remains of the flora in the Balde de Leyes, we know that if Ingentia, a large herbivore, lived there had to be enough vegetation to feed it”.

The site was a kind of savanna at the end of the Triassic. In addition to the dinosaurs that were discovered, there were also giant iguanas, turtles, and species with a shape similar to mice, which could be linked to the origin of mammals.

However, as the end of the Triassic approached, the environment became more arid, which ended up causing a series of extinctions that culminated 200 million years ago, after which new species would emerge in the Jurassic period. All this information has been preserved in the rocks of the new site and will be revealed in future campaigns and research.

Source: Agencia CTyS-UNLaM [July 10, 2018]




2018 July 11 Symbiotic R Aquarii Image Credit: Hubble, NASA,…

2018 July 11

Symbiotic R Aquarii
Image Credit: Hubble, NASA, ESA; Processing & License: Judy Schmidt

Explanation: You can see it change in brightness with just binoculars over the course of a year. Variable star R Aquarii is actually an interacting binary star system, two stars that seem to have a close, symbiotic relationship. About 710 light years away, this intriguing system consists of a cool red giant star and hot, dense white dwarf star in mutual orbit around their common center of mass. The binary system’s visible light is dominated by the red giant, itself a Mira-type long period variable star. But material in the cool giant star’s extended envelope is pulled by gravity onto the surface of the smaller, denser white dwarf, eventually triggering a thermonuclear explosion and blasting material into space. The featured image from the Hubble Space Telescope shows the still-expanding ring of debris which spans less than a light year and originated from a blast that would have been seen in the early 1770s. The evolution of less understood energetic events producing high energy emission in the R Aquarii system has been monitored since 2000 using Chandra X-ray Observatory data.

∞ Source: apod.nasa.gov/apod/ap180711.html


Tooth of 16,000-year-old cave lion discovered in France’s Puy-de-Dôme

A cave lion’s tooth has been discovered by archaeologists near Vic-le-Comte (Puy-de-Dôme), on a site that has been excavated for two years.

Tooth of 16,000-year-old cave lion discovered in France's Puy-de-Dôme
The cave lion disappeared about 10,000 years ago, at the end of the last Ice Age
[Credit: WikiCommons/Sehmur]

The tooth measures about 4 centimetres and is believed to date back 16,000 years. Several objects from the same period have already been found at the site.

The cave lion is close to the African lion. Males could weigh up to 300 kg. These animals disappeared about 10,000 years ago, at the end of the last Ice Age.

Tooth of 16,000-year-old cave lion discovered in France's Puy-de-Dôme
The cave lion’s tooth is believed to be 16,000 years old [Credit: La Montagne]

This discovery is a real surprise for Frédéric Surmely, heritage curator at the regional archaeology department of the Drac: “In 25 years of career and excavations, it is the first time that I have made such a discovery in Auvergne. There have been no others to my knowledge.”

However, he believes that “it is not surprising” to find the prehistoric animal in Auvergne: “What is surprising is the level at which it was found. At that point, global warming was already underway and the cave lion was in decline.”

This is not the first time that archaeologists have made a significant discovery in the area. In 2009, they had already found a mammoth molar just 150 metres from the lion’s tooth.

Source: Ouest-France [July 05, 2018]





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