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The worst land grab in decades in the Brazilian Amazon is threatening the survival of isolated tribes that have no contact with the outside world, a rights group said Wednesday.

Ranchers and settlers in the remotest reaches of northwestern Brazil are voraciously cutting down rainforest to farm crops, encroaching on the ancestral lands of three uncontacted groups, said Survival International.

The land grab is also threatening another tribe, the Uru Eu Wau Wau, or "Harpy Eagle" people, that has only limited contact with the outside world, said the London-based group.

Warning the groups face "annihilation," it accused local politicians in the state of Rondonia of backing the deforestation, even though the area is officially designated as an indigenous reserve and sits within a national park, Pacaas Novas.

Because isolated peoples' immune systems have never been exposed to the outside world's diseases, the land grab risks causing devastating outbreaks, Survival said.

"Around the world, industrialized society is stealing tribal lands in the pursuit of profit. What's happening in Brazil is simply a continuation of the invasion and genocide which characterized the European colonization of the Americas," said the group's director, Stephen Corry.

The organization quoted a letter the Harpy Eagle tribe sent to Brazilian police, in which they call the land grab "extremely serious."

"We are very worried because the invasions are close to our villages and putting the lives of women, old people, children and men at risk," said the letter.

Experts estimate between 50 and 90 percent of the populations of Brazil's isolated tribes were wiped out when the government initiated contact with them in the 1970s and 80s—official policy at the time.

Today, the government tries to avoid any contact with isolated peoples, in order to protect them.

Brazil is home to some 900,000 indigenous people from 305 different ethnic groups.

Source: AFP [October 27, 2016]

Researchers have observed wild-bearded capuchin monkeys in Brazil deliberately break stones, unintentionally creating flakes that share many of the characteristics of those produced by early Stone Age hominins. The difference is that the capuchins' flakes are not intentional tools for cutting and scraping, but seem to be the by-product of hammering or 'percussive behaviour' that the monkeys engage in to extract minerals or lichen from the stones.

In a paper, >published in Nature, the research team says this finding is significant because archaeologists had always understood that the production of multiple stone flakes with characteristics such as conchoidal fractures and sharp cutting edges was a behaviour unique to hominins. The paper suggests that scholars may have to refine their criteria for identifying intentionally produced early stone flakes made by hominins, given capuchins have been observed unintentionally making similar tools.

The research is authored by researchers from the University of Oxford, University College London and University of Sao Paulo in Brazil. The team observed individual monkeys in Serra da Capivara National Park unintentionally creating fractured flakes and cores. While hominins made stone flake tools for cutting and butchery tasks, the researchers admit that it is unclear why monkeys perform this behaviour. They suggest that the capuchins may be trying to extract powdered silicon (known to be an essential trace nutrient) or to remove lichen for some as yet unknown medicinal purpose. At no point did the monkeys try to cut or scrape using the flakes, says the study.

Lead author Dr Tomos Proffitt, from the School of Archaeology at the University of Oxford, comments: 'Within the last decade, studies have shown that the use and intentional production of sharp-edged flakes are not necessarily linked to early humans (the genus Homo) who are our direct relatives, but instead were used and produced by a wider range of hominins. However, this study goes one step further in showing that modern primates can produce archaeologically identifiable flakes and cores with features that we thought were unique to hominins.

'This does not mean that the earliest archaeological material in East Africa was not made by hominins. It does, however, raise interesting questions about the possible ways this stone tool technology developed before the earliest examples in the archaeological record appeared. It also tells us what this stone tool technology might look like. There are important questions too about the uniqueness of early hominin behaviour. These findings challenge previous ideas about the minimum level of cognitive and morphological complexity required to produce numerous conchoidal flakes.'

The monkeys were observed engaging in 'stone on stone percussion', whereby they individually selected rounded quartzite cobbles and then using one or two hands struck the 'hammer-stone' forcefully and repeatedly on quartzite cobbles embedded in a cliff face. This action crushed the surface and dislodged cobbled stones, and the hand-held 'hammer stones' became unintentionally fractured, leaving an identifiable primate archaeological record. As well as using the active hammer-stone to crush 'passive hammers' (stones embedded in the outcrop), the capuchins were also observed re-using broken hammer-stones as 'fresh' hammers.

The research team examined 111 fragmented stones collected from the ground immediately after the capuchins had dropped them, as well as from the surface and excavated areas in the site. They gathered complete and broken hammer-stones, complete and fragmented flakes and passive hammers. Around half of the fractured flakes exhibited conchoidal fracture, which is typically associated with the hominin production of flakes.

Bearded capuchins and some Japanese macaques are known to pound stones directly against each other, but the paper remarks that the capuchins in Serra da Capivara National Park are the only wild primates to be observed doing this for the purpose of damaging the stones.

Co-author and leader of the Primate Archaeology (Primarch) project Michael Haslam, from the University of Oxford, says: 'Our understanding of the new technologies adopted by our early ancestors helps shape our view of human evolution. The emergence of sharp-edged stone tools that were fashioned and hammered to create a cutting tool was a big part of that story. The fact that we have discovered monkeys can produce the same result does throw a bit of a spanner in the works in our thinking on evolutionary behaviour and how we attribute such artefacts. While humans are not unique in making this technology, the manner in which they used them is still very different to what the monkeys seem capable of.'

Source: University of Oxford [October 19, 2016]

Uplift associated with the Great Rift Valley of East Africa and the environmental changes it produced have puzzled scientists for decades because the timing and starting elevation have been poorly constrained.

Now paleontologists have tapped a fossil from the most precisely dated beaked whale in the world -- and the only stranded whale ever found so far inland on the African continent -- to pinpoint for the first time a date when East Africa's mysterious elevation began.

The 17 million-year-old fossil is from the beaked Ziphiidae whale family. It was discovered 740 kilometers inland at an elevation of 620 meters in modern Kenya's harsh desert region, said vertebrate paleontologist Louis L. Jacobs, Southern Methodist University, Dallas.

At the time the whale was alive, it would have been swimming far inland up a river with a low gradient ranging from 24 to 37 meters over more than 600 to 900 kilometers, said Jacobs, a co-author of the study.

The study, published in the Proceedings of the National Academy of Sciences, provides the first constraint on the start of uplift of East African terrain from near sea level.

"The whale was stranded up river at a time when east Africa was at sea level and was covered with forest and jungle," Jacobs said. "As that part of the continent rose up, that caused the climate to become drier and drier. So over millions of years, forest gave way to grasslands. Primates evolved to adapt to grasslands and dry country. And that's when -- in human evolution -- the primates started to walk upright."

Identified as a Turkana ziphiid, the whale would have lived in the open ocean, like its modern beaked cousins. Ziphiids, still one of the ocean's top predators, are the deepest diving air-breathing mammals alive, plunging to nearly 10,000 feet to feed, primarily on squid.

In contrast to most whale fossils, which have been discovered in marine rocks, Kenya's beached whale was found in river deposits, known as fluvial sediments, said Jacobs, a professor in the Roy M. Huffington Department of Earth Sciences of SMU's Dedman College of Humanities and Sciences. The ancient large Anza River flowed in a southeastward direction to the Indian Ocean. The whale, probably disoriented, swam into the river and could not change its course, continuing well inland.

"You don't usually find whales so far inland," Jacobs said. "Many of the known beaked whale fossils are dredged by fishermen from the bottom of the sea."

Determining ancient land elevation is very difficult, but the whale provides one near sea level.

"It's rare to get a paleo-elevation," Jacobs said, noting only one other in East Africa, determined from a lava flow.

Beaked whale fossil surfaced after going missing for more than 30 years

The beaked whale fossil was discovered in 1964 by J.G. Mead in what is now the Turkana region of northwest Kenya.

Mead, an undergraduate student at Yale University at the time, made a career at the Smithsonian Institution, from which he recently retired. Over the years, the Kenya whale fossil went missing in storage. Jacobs, who was at one time head of the Division of Paleontology for the National Museums of Kenya, spent 30 years trying to locate the fossil. His effort paid off in 2011, when he rediscovered it at Harvard University and returned it to the National Museums of Kenya.

The fossil is only a small portion of the whale, which Mead originally estimated was 7 meters long during its life. Mead unearthed the beak portion of the skull, 2.6 feet long and 1.8 feet wide, specifically the maxillae and premaxillae, the bones that form the upper jaw and palate.

The researchers reported their findings in "A 17 million-year-old whale constrains onset of uplift and climate change in East Africa" online at the PNAS web site.

Modern cases of stranded whales have been recorded in the Thames River in London, swimming up a gradient of 2 meters over 70 kilometers; the Columbia River in Washington state, a gradient of 6 meters over 161 kilometers; the Sacramento River in California, a gradient of 4 meters over 133 kilometers; and the Amazon River in Brazil, a gradient of 1 meter over 1,000 kilometers.

Source: Southern Methodist University [March 17, 2015]

The appearance of infectious diseases in new places and new hosts, such as West Nile virus and Ebola, is a predictable result of climate change, says a noted zoologist affiliated with the Harold W. Manter Laboratory of Parasitology at the University of Nebraska-Lincoln.

In an article published online today in conjunction with a special issue of the Philosophical Transactions of the Royal Society B, Daniel Brooks warns that humans can expect more such illnesses to emerge in the future, as climate change shifts habitats and brings wildlife, crops, livestock, and humans into contact with pathogens to which they are susceptible but to which they have never been exposed before.

"It's not that there's going to be one 'Andromeda Strain' that will wipe everybody out on the planet," Brooks said, referring to the 1971 science fiction film about a deadly pathogen. "There are going to be a lot of localized outbreaks putting pressure on medical and veterinary health systems. It will be the death of a thousand cuts."

Brooks and his co-author, Eric Hoberg, a zoologist with the U.S. National Parasite Collection of the USDA's Agricultural Research Service, have personally observed how climate change has affected very different ecosystems. During his career, Brooks has focused primarily on parasites in the tropics, while Hoberg has worked primarily in Arctic regions.

Each has observed the arrival of species that hadn't previously lived in that area and the departure of others, Brooks said.

"Over the last 30 years, the places we've been working have been heavily impacted by climate change," Brooks said in an interview last week. "Even though I was in the tropics and he was in the Arctic, we could see something was happening." Changes in habitat mean animals are exposed to new parasites and pathogens.

For example, Brooks said, after humans hunted capuchin and spider monkeys out of existence in some regions of Costa Rica, their parasites immediately switched to howler monkeys, where they persist today. Some lungworms in recent years have moved northward and shifted hosts from caribou to muskoxen in the Canadian Arctic.

But for more than 100 years, scientists have assumed parasites don't quickly jump from one species to another because of the way parasites and hosts co-evolve.

Brooks calls it the "parasite paradox." Over time, hosts and pathogens become more tightly adapted to one another. According to previous theories, this should make emerging diseases rare, because they have to wait for the right random mutation to occur.

However, such jumps happen more quickly than anticipated. Even pathogens that are highly adapted to one host are able to shift to new ones under the right circumstances.

Brooks and Hoberg call for a "fundamental conceptual shift" recognizing that pathogens retain ancestral genetic capabilities allowing them to acquire new hosts quickly.

"Even though a parasite might have a very specialized relationship with one particular host in one particular place, there are other hosts that may be as susceptible," Brooks said.

In fact, the new hosts are more susceptible to infection and get sicker from it, Brooks said, because they haven't yet developed resistance.

Though resistance can evolve fairly rapidly, this only changes the emergent pathogen from an acute to a chronic disease problem, Brooks adds.

"West Nile Virus is a good example - no longer an acute problem for humans or wildlife in North America, it nonetheless is hhere to stay," he said.

The answer, Brooks said, is for greater collaboration between the public and veterinary health communities and the "museum" community - the biologists who study and classify life forms and how they evolve.

In addition to treating human cases of an emerging disease and developing a vaccine for it, he said, scientists need to learn which non-human species carry the pathogen.

Knowing the geographic distribution and the behavior of the non-human reservoirs of the pathogen could lead to public health strategies based on reducing risk of infection by minimizing human contact with infected animals, much likethose that reduced the incidence of malaria and yellow fever by reducing human contact with mosquitos.

Museum scientists versed in understanding the evolutionary relationships among species could use this knowledge to anticipate the risk of the pathogen becoming established outside of its native range.

Brooks, who earned his bachelor's and master's degrees from the University of Nebraska-Lincoln, was a zoology professor at the University of Toronto for 30 years until he retired early in 2011 to devote more time to his study of emerging infectious disease. In addition to being a senior research fellow with UNL's Manter Laboratory, he is a visiting senior fellow at the Universidade Federal do Parana, Brazil, funded by the Ciencias sem Fronteiras (Sciences without Borders) of the Brazilian government, and a visiting scholar with Debrecen University in Hungary.

Brooks' and Hoberg's article, "Evolution in action: climate change, biodiversity dynamics and emerging infectious disease," is part of a Philosophical Transactions of the Royal Society B issue on "Climate change and vector-borne diseases of humans," edited by Paul Parham, a specialist in infectious disease epidemiology at Imperial College in London.

"We have to admit we're not winning the war against emerging diseases," Brooks said. "We're not anticipating them. We're not paying attention to their basic biology, where they might come from and the potential for new pathogens to be introduced."

Source: University of Nebraska-Lincoln [February 16, 2015]

Astronomers have discovered a 'treasure trove' of rare dwarf satellite galaxies orbiting our own Milky Way. The discoveries could hold the key to understanding dark matter, the mysterious substance which holds our galaxy together.

A team of astronomers from the University of Cambridge have identified nine new dwarf satellites orbiting the Milky Way, the largest number ever discovered at once. The findings, from newly-released imaging data taken from the Dark Energy Survey, may help unravel the mysteries behind dark matter, the invisible substance holding galaxies together.

The new results also mark the first discovery of dwarf galaxies -- small celestial objects that orbit larger galaxies -- in a decade, after dozens were found in 2005 and 2006 in the skies above the northern hemisphere. The new satellites were found in the southern hemisphere near the Large and Small Magellanic Cloud, the largest and most well-known dwarf galaxies in the Milky Way's orbit.

The Cambridge findings are being jointly released today with the results of a separate survey by astronomers with the Dark Energy Survey, headquartered at the US Department of Energy's Fermi National Accelerator Laboratory. Both teams used the publicly available data taken during the first year of the Dark Energy Survey to carry out their analysis.

The newly discovered objects are a billion times dimmer than the Milky Way, and a million times less massive. The closest is about 95,000 light years away, while the most distant is more than a million light years away.

According to the Cambridge team, three of the discovered objects are definite dwarf galaxies, while others could be either dwarf galaxies or globular clusters -- objects with similar visible properties to dwarf galaxies, but not held together with dark matter.

"The discovery of so many satellites in such a small area of the sky was completely unexpected," said Dr Sergey Koposov of Cambridge's Institute of Astronomy, the study's lead author. "I could not believe my eyes."

Dwarf galaxies are the smallest galaxy structures observed, the faintest of which contain just 5000 stars -- the Milky Way, in contrast, contains hundreds of billions of stars. Standard cosmological models of the universe predict the existence of hundreds of dwarf galaxies in orbit around the Milky Way, but their dimness and small size makes them incredibly difficult to find, even in our own 'backyard'.

"The large dark matter content of Milky Way satellite galaxies makes this a significant result for both astronomy and physics," said Alex Drlica-Wagner of Fermilab, one of the leaders of the Dark Energy Survey analysis.

Since they contain up to 99 percent dark matter and just one percent observable matter, dwarf galaxies are ideal for testing whether existing dark matter models are correct. Dark matter -- which makes up 25 percent of all matter and energy in our universe -- is invisible, and only makes its presence known through its gravitational pull.

"Dwarf satellites are the final frontier for testing our theories of dark matter," said Dr Vasily Belokurov of the Institute of Astronomy, one of the study's co-authors. "We need to find them to determine whether our cosmological picture makes sense. Finding such a large group of satellites near the Magellanic Clouds was surprising, though, as earlier surveys of the southern sky found very little, so we were not expecting to stumble on such treasure."

The closest of these pieces of 'treasure' is 97,000 light years away, about halfway to the Magellanic Clouds, and is located in the constellation of Reticulum, or the Reticle. Due to the massive tidal forces of the Milky Way, it is in the process of being torn apart.

The most distant and most luminous of these objects is 1.2 million light years away in the constellation of Eridanus, or the River. It is right on the fringes of the Milky Way, and is about to get pulled in. According to the Cambridge team, it looks to have a small globular cluster of stars, which would make it the faintest galaxy to possess one.

"These results are very puzzling," said co-author Wyn Evans, also of the Institute of Astronomy. "Perhaps they were once satellites that orbited the Magellanic Clouds and have been thrown out by the interaction of the Small and Large Magellanic Cloud. Perhaps they were once part of a gigantic group of galaxies that -- along with the Magellanic Clouds -- are falling into our Milky Way galaxy."

The Dark Energy Survey is a five-year effort to photograph a large portion of the southern sky in unprecedented detail. Its primary tool is the Dark Energy Camera, which -- at 570 megapixels -- is the most powerful digital camera in the world, able to see galaxies up to eight billion light years from Earth. Built and tested at Fermilab, the camera is now mounted on the four-metre Victor M Blanco telescope at the Cerro Tololo Inter-American Observatory in the Andes Mountains in Chile. The camera includes five precisely shaped lenses, the largest nearly a yard across, designed and fabricated at University College London (UCL) and funded by the UK Science and Technology Facilities Council (STFC).

The Dark Energy Survey is supported by funding from the STFC, the US Department of Energy Office of Science; the National Science Foundation; funding agencies in Spain, Brazil, Germany and Switzerland; and the participating institutions.

The Cambridge research, funded by the European Research Council, will be published in The Astrophysical Journal.

Source: University of Cambridge [March 10, 2015]

Genes that drive the shape of human noses have been identified by a UCL-led study. The four genes mainly affect the width and 'pointiness' of noses which vary greatly between different populations. The new information adds to our understanding of how the human face evolved and may help contribute to forensic DNA technologies that build visual profiles based on an individual's genetic makeup.

The study, published today in >Nature Communications, analysed a population of over 6,000 people with varied ancestry across Latin America to study the differences in normal facial features and identify the genes which control the shape of the nose and chin.

The researchers identified five genes which play a role in controlling the shape of specific facial features. DCHS2, RUNX2, GLI3 and PAX1 affect the width and pointiness of the nose and another gene -- EDAR -- affects chin protrusion.

"Few studies have looked at how normal facial features develop and those that have only looked at European populations, which show less diversity than the group we studied. What we've found are specific genes which influence the shape and size of individual features, which hasn't been seen before.

"Finding out the role each gene plays helps us to piece together the evolutionary path from Neanderthal to modern humans. It brings us closer to understanding how genes influence the way we look, which is important for forensics applications," said the first author of the report, Dr Kaustubh Adhikari, UCL Cell & Developmental Biology.

People have different shaped facial features based on their genetic heritage and this is partly due to how the environment influenced the evolution of the human genome. The nose, for example, is important for regulating the temperature and humidity of the air we breathe in so developed different shapes in warmer and cooler climates.

"It has long been speculated that the shape of the nose reflects the environment in which humans evolved. For example, the comparatively narrower nose of Europeans has been proposed to represent an adaptation to a cold, dry climate. Identifying genes affecting nose shape provides us with new tools to examine this question, as well as the evolution of the face in other species. It may also help us understand what goes wrong in genetic disorders involving facial abnormalities," explained Professor Andrés Ruiz-Linares UCL Biosciences, who led the study.

The team collected and analysed DNA samples from 6,630 volunteers from the CANDELA cohort recruited in Brazil, Colombia, Chile, Mexico and Peru. After an initial screen, a sample size of 5,958 was used. This group included individuals of mixed European (50%), Native American (45%) and African (5%) ancestry, resulting in a large variation in facial features.

Both men and women were assessed for 14 different facial features and whole genome analysis identified the genes driving differences in appearance.

A subgroup of 3,000 individuals had their features assessed using a 3D reconstruction of the face in order to obtain exact measurements of facial features and the results identified the same genes.

The study identified genes that are involved in bone and cartilage growth and the development of the face. GLI3, DCHS2 and PAX1 are all genes known to drive cartilage growth -- GLI3 gave the strongest signal for controlling the breadth of nostrils, DCHS2 was found to control nose 'pointiness' and PAX1 also influences nostril breadth. RUNX2 which drives bone growth was seen to control nose bridge width.

The genes GLI3, DCHS2 and RUNX2 are known to show strong signals of recent selection in modern humans compared to archaic humans such as Neanderthals and Denisovans; GLI3 in particular undergoing rapid evolution.

Source: University College London [May 19, 2016]

A new study says that more than 17,000 marine species worldwide remain largely unprotected, with the U.S. among the bottom in supporting formal marine protected areas (MPAs) that could safeguard marine biodiversity.

The study, which is the first comprehensive assessment of protected areas coverage on marine life, appears in the international journal Scientific Reports. Authors include scientists from University of Queensland, the Australian Research Council Centre of Excellence for Environmental Decisions (CEED), UC Santa Barbara, the National Center for Ecological Analysis and Synthesis, Imperial College London and the Wildlife Conservation Society.

The authors looked at the ranges of some 17,348 species of marine life, including whales, sharks rays and fish, and found that 97.4 percent have less than 10 percent of their range represented in marine protected areas. Nations with the largest number of "gap species" or species whose range lie entirely outside of protected areas include the U.S., Canada, and Brazil.

Despite these dismal results, the authors say the study underscores opportunities to achieve goals set by the Convention on Biological Diversity to protect 10 percent of marine biodiversity by 2020. For example, the majority of species that were considered very poorly represented (less than two percent of their range found in marine protected areas) are found in exclusive economic zones. This suggests an important role for particular nations to better protect biodiversity.

"The process of establishing MPAs is not trivial as they impact livelihoods. It is essential that new MPAs protect biodiversity whilst minimizing negative social and economic impacts. The results of this study offer strategic guidance on where MPAs could be placed to better protect marine biodiversity." said the study's lead author Dr Carissa Klein of the University of Queensland and CEED.

The authors say that it is imperative that new MPAs are systematically identified and take into account what has already been protected in other places, in addition to socioeconomic costs of implementation, feasibility of success, other aspects driving biodiversity.

"The increase in the number MPAs in recent years is encouraging, but most of this increase has come from a few very large MPAs," said Dr. Ben Halpern of UC Santa Barbara and NCEAS. "Those very large MPAs provide important value, but they can be misleading in thinking that biodiversity is being well protected because of them. Species all around the planet need protection, not just those in some locations. Our results point out where the protection gaps exist."

Said co-author Dr. James Watson of WCS and the University of Queensland: "As most marine biodiversity remains extremely poorly represented, the task of implementing an effective network of MPAs is urgent. Achieving this goal is imperative for not just for nature but for humanity, as millions of people depend on marine biodiversity for important and valuable services."

Source: Wildlife Conservation Society [December 03, 2015]

Extensive systems of fossilised riverbeds have been discovered on an ancient region of the Martian surface, supporting the idea that the now cold and dry Red Planet had a warm and wet climate about 4 billion years ago, according to UCL-led research>.

The study, >published in Geology and funded by the Science & Technology Facilities Council and the UK Space Agency, identified over 17,000km of former river channels on a northern plain called Arabia Terra, providing further evidence of water once flowing on Mars.

"Climate models of early Mars predict rain in Arabia Terra and until now there was little geological evidence on the surface to support this theory. This led some to believe that Mars was never warm and wet but was a largely frozen planet, covered in ice-sheets and glaciers. We've now found evidence of extensive river systems in the area which supports the idea that Mars was warm and wet, providing a more favourable environment for life than a cold, dry planet," explained lead author, Joel Davis (UCL Earth Sciences).

Since the 1970s, scientists have identified valleys and channels on Mars which they think were carved out and eroded by rain and surface runoff, just like on Earth. Similar structures had not been seen on Arabia Terra until the team analysed high resolution imagery from NASA's Mars Reconnaissance Orbiter (MRO) spacecraft.

The new study examined images covering an area roughly the size of Brazil at a much higher resolution than was previously possible -- 6 metres per pixel compared to 100 metres per pixel. While a few valleys were identified, the team revealed the existence of many systems of fossilised riverbeds which are visible as inverted channels spread across the Arabia Terra plain.

The inverted channels are similar to those found elsewhere on Mars and Earth. They are made of sand and gravel deposited by a river and when the river becomes dry, the channels are left upstanding as the surrounding material erodes. On Earth, inverted channels often occur in dry, desert environments like Oman, Egypt, or Utah, where erosion rates are low -- in most other environments, the channels are worn away before they can become inverted.

"The networks of inverted channels in Arabia Terra are about 30m high and up to 1-2km wide, so we think they are probably the remains of giant rivers that flowed billions of years ago. Arabia Terra was essentially one massive flood plain bordering the highlands and lowlands of Mars. We think the rivers were active 3.9-3.7 billion years ago, but gradually dried up before being rapidly buried and protected for billions of years, potentially preserving any ancient biological material that might have been present," added Joel Davis.

"These ancient Martian flood plains would be great places to explore to search for evidence of past life. In fact, one of these inverted channels called Aram Dorsum is a candidate landing site for the European Space Agency's ExoMars Rover mission, which will launch in 2020," said Dr Matthew Balme, Senior Lecturer at The Open University and co-author of the study.

The researchers now plan on studying the inverted channels in greater detail, using higher-resolution data from MRO's HiRISE camera.

Source: University College London [August 23, 2016]