Oct 27, 2023

Uranus aurora discovery offers clues to habitable icy worlds

The presence of an infrared aurora on the cold, outer planet of Uranus has been confirmed for the first time by University of Leicester astronomers.

The discovery could shed light on the mysteries behind the magnetic fields of the planets of our solar system, and even on whether distant worlds might support life.

The team of scientists, supported by the Science and Technology Facilities Council (STFC), have obtained the first measurements of the infrared (IR) aurora at Uranus since investigations began in 1992. While the ultraviolet (UV) aurorae of Uranus has been observed since 1986, no confirmation of the IR aurora had been observed until now. The scientists' conclusions have been published in the journal Nature Astronomy.

The ice giants Uranus and Neptune are unusual planets in our solar system as their magnetic fields are misaligned with the axes in which they spin. While scientists have yet to find an explanation for this, clues may lie in Uranus's aurora.

Aurorae are caused by highly energetic charged particles, which are funnelled down and collide with a planet's atmosphere via the planet's magnetic field lines. On Earth, the most famous result of this process are the spectacles of the Northern and Southern Lights. At planets such as Uranus, where the atmosphere is predominately a mix of hydrogen and helium, this aurora will emit light outside of the visible spectrum and in wavelengths such as the infrared (IR).

The team used infrared auroral measurements taken by analysing specific wavelengths of light emitted from the planet, using the Keck II telescope. From this, they can analyse the light (known as emission lines) from these planets, similar to a barcode. In the infrared spectrum, the lines emitted by a charged particle known as H3+ will vary in brightness depending on how hot or cold the particle is and how dense this layer of the atmosphere is. Hence, the lines act like a thermometer into the planet.

Their observations revealed distinct increases in H3+ density in Uranus's atmosphere with little change in temperature, consistent with ionisation caused by the presence of an infrared aurora. Not only does this help us better understand the magnetic fields of the outer planets of our own solar system, but it may also help in identifying other planets that are suitable of supporting life.

Lead author Emma Thomas, a PhD student in the University of Leicester School of Physics and Astronomy, said: "The temperature of all the gas giant planets, including Uranus, are hundreds of degrees Kelvin/Celsius above what models predict if only warmed by the sun, leaving us with the big question of how these planets are so much hotter than expected? One theory suggests the energetic aurora is the cause of this, which generates and pushes heat from the aurora down towards the magnetic equator.

"A majority of exoplanets discovered so far fall in the sub-Neptune category, and hence are physically similar to Neptune and Uranus in size. This may also mean similar magnetic and atmospheric characteristics too. By analysing Uranus's aurora which directly connects to both the planet's magnetic field and atmosphere, we can make predictions about the atmospheres and magnetic fields of these worlds and hence their suitability for life.

"This paper is the culmination of 30 years of auroral study at Uranus, which has finally revealed the infrared aurora and begun a new age of aurora investigations at the planet. Our results will go on to broaden our knowledge of ice giant auroras and strengthen our understanding of planetary magnetic fields in our solar system, at exoplanets and even our own planet."

The results may also give scientists an insight into a rare phenomenon on Earth, in which the north and south pole switch hemisphere locations known as geomagnetic reversal.

Read more at Science Daily

75% of exclusive hardwood may be illegally harvested

The tropical wood type ipê is popular for building exclusive wooden decks, and in North America and Europe, the demand for the material has increased sharply. Now, a study from Chalmers University of Technology, Sweden, shows that more than three-quarters of all ipêfrom the top producing region in Brazil could have been harvested illegally. "The study reveals where in the chain the greatest risks lie. It can be a tool to counteract illegal logging," says Caroline S.S. Franca, PhD student at Chalmers.

Ipê is one of the world's hardest woods. It is therefore particularly suitable for building balconies, conservatories, stairs or piers. Demand for the exclusive, tropical wood has increased steadily in recent years, especially on European, American and Canadian markets. In Brazil, the country of origin for 96 percent of all ipê on the market, exports have increased by over 76 percent in volume over the past decade.

This development means an increased risk of illegal logging of ipê, which in November 2022 was included on the Cites list of species threatened by overexploitation due to its popularity and increasing demand through international trade.

"Some products from the rainforest are more valuable and therefore more vulnerable to illegal logging. Ipê is at the top of that list. At the same time, ipê trees grow slowly, which means that regrowth takes a long time. The risk of extinction is real, and today there are no reliable figures on the amount of remaining trees and the damage to existing stands that has already been done," says Caroline S.S. Franca, PhD student in Physical Resource Theory at Chalmers.

Mapping where risks are greatest

Caroline S.S. Franca is the lead author of a research study on the risks for illegal logging of ipê in Brazil, which was recently published in Nature Sustainability. In the study, the researchers analysed extensive amounts of data to identify where in the supply chains there are significant risks that logging has taken place illegally.

The conclusion is that more than three-quarters of all ipê from Pará -- the top producing state of this wood in Brazil and a major source of exports -- in the period 2009-2019 may have been illegally harvested.

"In the study, we see, for example, that 16 percent of the ipê that ends up on the market is harvested without proper permits, and that landowners claim that they have felled more ipê on their land than is likely to exist on the stated area. We also show that there is more wood in circulation than the official production figures indicate," she says.

Paving the way for better enforcement and practices

"We know that illegal logging is driving forest degradation, and is linked to organised crime, conflict and the destruction of forest-dependent local communities," continues Caroline S.S. Franca, adding that "degradation of Amazon forests does not only affect the local environment and the ecological diversity of the rainforest, it is also as large of a contributor to climate change as outright deforestation."

She hopes that her research results can contribute to an increased awareness of the extent of illegal logging among decision-makers and actors in the supply chain, as well as among consumers.

"The novel methods developed in the study, exploring existing patterns in the data for transactions and approvals of ipê exploration have an enormous potential both to improve forest control systems in Brazil, as well as to support supply-chain actors in their efforts to make timber sourcing more responsible and sustainable," says Marco Lentini, a co-author of the study with a long-standing experience working on sustainable forest management in the Brazilian Amazon.

The information already exists, now there is political will to use it

Recent numbers form Brazil's forest monitoring system shows that deforestation in the Amazon have been almost halved in 2023, compared to last year. Brazilian President Luiz Inácio Lula da Silva also initiated the so-called Belém Declaration -- an alliance among eight South American countries to combat the deforestation of the Amazon, adopted on August 8, 2023.

"This declaration is a welcome expression of renewed political will to reduce deforestation," comments Martin Persson, co-author of the ipê study and a Chalmers researcher with extensive experience of research on the devastation of the Amazon.

But he also emphasises that the danger is far from over, and that the declaration itself will not lead to change.

"Halting deforestation and forest degradation requires concrete policy measures. And what we point out in our study is that there is already data and information that can be used by authorities to get to those who harvest forests illegally," he says.

Important for consumers to ask questions

There is a certification for sustainably produced wood, FSC, which can serve as a guide for consumers who want to avoid buying non-sustainable or illegally harvested wood. But regardless of whether the wood has an FSC certification or not, Caroline S.S. Franca emphasises that it is always important to ask a few basic questions before buying.

"Where exactly does the wood come from? Is there documentation of the origin of the wood and its path through the production chain? As a consumer, you have a greater opportunity to make an informed decision if you get answers to those questions," she says.

Read more at Science Daily

Scientists find two ways that hurricanes rapidly intensify

Hurricanes that rapidly intensify for mysterious reasons pose a particularly frightening threat to those in harm's way. Forecasters have struggled for many years to understand why a seemingly commonplace tropical depression or tropical storm sometimes blows up into a major hurricane, packing catastrophic winds and driving a potentially deadly surge of water toward shore.

Now scientists have shed some light on why this forecasting challenge has been so difficult to overcome: there's more than one mechanism that causes rapid intensification. New research by scientists at the U.S. National Science Foundation (NSF) National Center for Atmospheric Research (NCAR) uses the latest computer modeling techniques to identify two entirely different modes of rapid intensification. The findings may lead to better understanding and prediction of these dangerous events.

"Trying to find the holy grail behind rapid intensification is the wrong approach because there isn't just one holy grail," said NCAR scientist Falko Judt, lead author of the new study. "There are at least two different modes or flavors of rapid intensification, and each one has a different set of conditions that must be met in order for the storm to strengthen so quickly."

One of the modes discussed by Judt and his co-authors occurs when a hurricane intensifies symmetrically, fueled by favorable environmental conditions such as warm surface waters and low wind shear. This type of abrupt strengthening is associated with some of the most destructive storms in history, such as Hurricanes Andrew, Katrina, and Maria. Meteorologists were stunned this week when the winds of Hurricane Otis defied predictions and exploded by 110 miles per hour in just 24 hours, plowing into the west coast of Mexico at category 5 strength.

Judt and his co-authors also identified a second mode of rapid intensification that had previously been overlooked because it doesn't lead to peak winds reaching such destructive levels. In the case of this mode, the strengthening can be linked to major bursts of thunderstorms far from the storm's center. These bursts trigger a reconfiguration of the cyclone's circulation, enabling it to intensify rapidly, reaching category 1 or 2 intensity within a matter of hours.

This second mode is more unexpected because it typically occurs in the face of unfavorable conditions, such as countervailing upper-level winds that shear the storm by blowing the top in a different direction than the bottom.

"Those storms are not as memorable and they're not as significant," Judt said. "But forecasters need to be aware that even a storm that's strongly sheared and asymmetric can undergo a mode of rapid intensification."

The new study appeared in the Monthly Weather Review, a journal of the American Meteorological Society. It was funded by the U.S. Navy Office of Naval Research and by the U.S. National Science Foundation, which is NCAR's sponsor. It was co-authored by NCAR scientists Rosimar Rios-Berrios and George Bryan.

A serendipitous finding

Rapid intensification occurs when the winds of a tropical cyclone increase by 30 knots (about 35 miles per hour) in a 24-hour period. Judt came across the two modes of rapid intensification when working on an unrelated project.

The discovery emerged after Judt produced a very high-resolution, 40-day computer simulation of the global atmosphere, using the NCAR-based Model for Prediction Across Scales (MPAS). That simulation, run at the NCAR-Wyoming Supercomputing Center, was designed for an international project comparing the output of leading atmospheric models, which have achieved unprecedented detail because of increasingly powerful supercomputers.

Once Judt produced the model, he was curious to examine storms in the simulation that rapidly intensified. By looking at a number of cases across the world's ocean basins, he noticed that rapid intensification occurred in two distinct ways. This had not previously been apparent in models, partly because previous simulations captured only individual regions instead of allowing scientists to track a spectrum of hurricanes and typhoons across the world's oceans.

Judt and his co-authors then combed through actual observations of tropical cyclones and found a number of real-world instances of both modes of rapid intensification.

"It was kind of a serendipitous finding," Judt said. "Just by looking at the storms in the simulation and making plots, I realized that storms that rapidly intensify fall into two different camps. One is the canonical mode in which there's a tropical storm when you go to bed and when you wake up it's a category 4. But then there's another mode that goes from a tropical storm to a category 1 or 2, and it fits the definition of rapid intensification. Since nobody has those storms on their radar, that mode of rapid intensification went undetected until I went through the simulation."

Meteorologists have long known that favorable environmental conditions, including very warm surface waters and minimal wind shear, can generate rapid intensification and bring a cyclone to category 4 or 5 strength with sustained winds of 130 mph or higher. In their new paper, Judt and his co-authors referred to that mode of rapid intensification as a marathon because the storm keeps intensifying symmetrically at a moderate pace while the primary vortex steadily amplifies.

Judt described Hurricane Otis as a fast marathon because it intensified symmetrically but at an unusually rapid pace, marked by an 80 mph increase in wind speed during a 12-hour period.

The study team labeled the other mode of rapid intensification as a sprint because the intensification is extremely quick but generally doesn't last as long, with storms peaking at category 1 or 2 strength and sustained winds of 110 mph or less. In such cases, explosive bursts of thunderstorms lead to a rearrangement of the cyclone and the emergence of a new center, enabling the storm to become more powerful -- even in the face of adverse environmental conditions.

The paper concludes that the two modes may represent opposite ends of a spectrum, with many cases of rapid intensification falling somewhere in between. For instance, rapid intensification may begin with a chain of discrete events such as a burst of thunderstorms that are characteristic of the sprint mode, but then transition into a more symmetrical mode of intensification that is characteristic of the marathon mode.

A question for future research is why bursts of thunderstorms can cause about 10% of storms in an unconducive environment to rapidly intensify, even though the other 90% do not, Judt said.

Read more at Science Daily

Fruit, nectar, bugs and blood: How bat teeth and jaws evolved for a diverse dinnertime

They don't know it, but Darwin's finches changed the world. These closely related species -- native to the Galapagos Islands -- each sport a uniquely shaped beak that matches their preferred diet. Studying these birds helped Charles Darwin develop the theory of evolution by natural selection.

A group of bats has a similar -- and more expansive -- evolutionary story to tell. There are more than 200 species of noctilionoid bats, mostly in the American tropics. And despite being close relatives, their jaws evolved in wildly divergent shapes and sizes to exploit different food sources. A paper published Aug. 22 in Nature Communications shows those adaptations include dramatic, but also consistent, modifications to tooth number, size, shape and position. For example, bats with short snouts lack certain teeth, presumably due to a lack of space. Species with longer jaws have room for more teeth -- and, like humans, their total tooth complement is closer to what the ancestor of placental mammals had.

According to the research team behind this study, comparing noctilionoid species can reveal a lot about how mammalian faces evolved and developed, particularly jaws and teeth. And as a bonus, they can also answer some outstanding questions about how our own pearly whites form and grow.

"Bats have all four types of teeth -- incisors, canines, premolars and molars -- just like we do," said co-author Sharlene Santana, a University of Washington professor of biology and curator of mammals at the Burke Museum of Natural History & Culture. "And noctilionoid bats evolved a huge diversity of diets in as little as 25 million years, which is a very short amount of time for these adaptations to occur."

"There are noctilionoid species that have short faces like bulldogs with powerful jaws that can bite the tough exterior of the fruits that they eat. Other species have long snouts to help them drink nectar from flowers. How did this diversity evolve so quickly? What had to change in their jaws and teeth to make this possible?" said lead author Alexa Sadier, an incoming faculty member at the Institute of Evolutionary Science of Montpellier in France, who began this project as a postdoctoral researcher at the University California, Los Angeles.

Scientists don't know what triggered this frenzy of dietary adaptation in noctilionoid bats. But today different noctilionoid species feast on insects, fruit, nectar, fish and even blood -- since this group also includes the infamous vampire bats.

The team used CT scans and other methods to analyze the shapes and sizes of jaws, premolars and molars in more than 100 noctilionoid species. The bats included both museum specimens and a limited number of wild bats captured for study purposes. The researchers compared the relative sizes of teeth and other cranial features among species with different types of diets, and used mathematical modeling to determine how those differences are generated during development.

The team found that, in noctilionoid bats, certain "developmental rules" caused them to generate the right assortment of teeth to fit in their diet-formed grins. For example, bats with long jaws -- like nectar-feeders -- or intermediate jaws, like many insect-eaters, tended to have the usual complement of three premolars and three molars on each side of the jaw. But bats with short jaws, including most fruit-eating bats, tended to ditch the middle premolar or the back molar, if not both.

"When you have more space, you can have more teeth," said Sadier. "But for bats with a shorter space, even though they have a more powerful bite, you simply run out of room for all these teeth."

Having a shorter jaw may also explain why many short-faced bats also tended to have wider front molars.

"The first teeth to appear tend to grow bigger since there is not enough space for the next ones to emerge," said Sadier.

"This project is giving us the opportunity to actually test some of the assumptions that have been made about how tooth growth, shape and size are regulated in mammals," said Santana. "We know surprisingly little about how these very important structures develop!"

Many studies about mammalian tooth development were done in mice, which have only molars and heavily modified incisors. Scientists are not entirely sure if the genes and developmental patterns that control tooth development in mice also operate in mammals with more "ancestral" sets of chompers -- like bats and humans.

Sadier, Santana and their colleagues believe their project, which is ongoing, can start to answer these questions in bats -- along with many other outstanding questions about how evolution shapes mammalian features. They're expanding this study to include noctilionoid incisors and canines, and hope to uncover more of the genetic and developmental mechanisms that control tooth development in this diverse group of bats.

"We see such strong selective pressures in these bats: Shapes have to closely match their function," said Santana. "I think there are many more evolutionary secrets hidden in these species."

Read more at Science Daily

Oct 26, 2023

Massive space explosion observed creating elements needed for life

Scientists have observed the creation of rare chemical elements in the second-brightest gamma-ray burst ever seen -- casting new light on how heavy elements are made.

Researchers examined the exceptionally bright gamma-ray burst GRB 230307A, which was caused by a neutron star merger. The explosion was observed using an array of ground and space-based telescopes, including NASA's James Webb Space Telescope, Fermi Gamma-ray Space Telescope, and Neil Gehrels Swift Observatory.

Publishing their findings today in Nature (25 Oct), the international research team which included experts from the University of Birmingham, reveal that they found the heavy chemical element tellurium, in the aftermath of the explosion.

Other elements such as iodine and thorium, which are needed to sustain life on earth, are also likely to be amongst the material ejected by the explosion, also known as a kilonova.

Dr Ben Gompertz, Assistant Professor of Astronomy at the University of Birmingham, and co-author of the study explains: "Gamma-ray bursts come from powerful jets travelling at almost the speed of light -- in this case driven by a collision between two neutron stars. These stars spent several billion years spiralling towards one another before colliding to produce the gamma-ray burst we observed in March this year. The merger site is the approximate length of the Milky Way (about 120,000 light-years) outside of their home galaxy, meaning they must have been launched out together.

"Colliding neutron stars provide the conditions needed to synthesise very heavy elements, and the radioactive glow of these new elements powered the kilonova we detected as the blast faded. Kilonovae are extremely rare and very difficult to observe and study, which is why this discovery is so exciting."

GRB 230307A was one of the brightest gamma-ray bursts ever observed -- over a million times brighter than the entire Milky Way Galaxy combined. This is the second time individual heavy elements have been detected using spectroscopic observations after a neutron star merger, providing invaluable insight into how these vital building blocks needed for life are formed.

Lead author of the study Andrew Levan, Professor of Astrophysics at Radboud University in the Netherlands, said: "Just over 150 years since Dmitri Mendeleev wrote down the periodic table of elements, we are now finally in the position to start filling in those last blanks of understanding where everything was made, thanks to the James Webb Telescope."

GRB 230307A lasted for 200 seconds, meaning it is categorised as a long-duration gamma-ray burst. This is unusual as short gamma-ray bursts, which last less than two seconds, are more commonly caused by neutron star mergers. Long gamma-ray bursts like this one are usually caused by the explosive death of a massive star.

The researchers are now seeking to learn more about how these neutron star mergers work and how they power these huge element-generating explosions.

Dr Samantha Oates, a co-author of the study while a postdoctoral research fellow at the University of Birmingham (now a lecturer at Lancaster University) said: "Just a few short years ago discoveries like this one would not have been possible, but thanks to the James Webb Space Telescope we can observe these mergers in exquisite detail."

Read more at Science Daily

Bizarre new fossils shed light on ancient plankton

A scientist from the University of Leicester has discovered a new type of fossil that reveals life in the oceans half a billion years ago.

The tiny organisms, detailed in a new study in the journal Proceedings of the Royal Society B, resemble modern-day algae and might also give scientists an insight into the climate changes that affected our oceans.

The fossils are microscopic and look like spiny balls connected together. The study's author Dr Tom Harvey, from the University of Leicester School of Geography, Geology and the Environment, said: "When I first saw them, I had no idea what they were. I wondered if they could be animal eggs, or some new type of organism. There's nothing quite like them, living or extinct."

But as further specimens came to light, Dr Harvey identified similarities with modern green algae that live floating in the plankton of ponds and lakes. He explains: "The fossils have the same sort of colonial structure as the modern algae, with cells linking together, explaining their neat, geometric arrangements. Surprisingly, though, the fossil examples lived in the sea, giving a rare glimpse of the early marine plankton."

The importance of the fossils lies in their immense age. They lived around the time when animals were first evolving, during the Cambrian 'explosion' of life -- and this is probably no coincidence. In today's world, phytoplankton provides the fundamental food source for almost all life in the oceans. However, the modern groups of phytoplankton evolved relatively recently, and we do not know which groups inhabited the Cambrian oceans.

Dr Harvey explains: "When we look at modern plankton, we see that algae develop colonies when animals are trying to eat them. It's a defence mechanism. So, the existence of colonial algae in the Cambrian Period suggests that early animals were evolving to feed in the plankton, starting a predator-prey relationship that has continued ever since.

"Considering that the plankton underpins life in the oceans, and fossil plankton helps us build ancient climate models, these small fossils have a big role in telling the history of life on Earth."

The new discovery will prompt a re-think on other early microfossils. For years, scientists have thought that the spiny balls found individually were the dormant cysts of single-celled life.

Read more at Science Daily

Rider on the storm: Shearwater seabird catches an 11 hour ride over 1,000 miles in a typhoon

New research from Japan published in the Ecological Society of America's journal Ecology suggests that increasingly severe weather driven by climate change may push oceangoing seabirds to their limits.

In August 2019, Kozue Shiomi, a seabird biologist at Tohoku University, attached GPS bio-loggers to 14 adult streaked shearwaters (Calonectris leucomelas) from a nesting colony on Mikurajima, a small island near Tokyo, as part of a study on the species homing behavior.

In September of that same year, an exceptionally powerful storm, Typhoon Faxai, barreled into southeastern Japan, causing considerable physical damage to the mainland. But the typhoon, with windspeeds nearing 200 km/hr, also provided scientists with a rare glimpse into the capacity of seabirds to withstand extreme storm conditions -- conditions that seabirds may increasingly be faced with under future climates.

Analysis of tracking data following the passage of Typhoon Faxai revealed that, while most of the tagged shearwaters appeared to be either unaffected by or had managed to circumvent the storm, one male had not been so lucky. Over the 11-hour period during which this shearwater bird was tracked, it completed five full circular loops of 50-80 km diameter each and was transported a total distance of 1,146 km.

Under normal conditions, streaked shearwaters typically fly at speeds of 10-60 km/hr and altitudes below 100 m, and remain at sea; by contrast, tracking data indicated that the bird caught in the storm had attained speeds of 90-170 km/hr, soared to an altitude of 4700 m, and was carried over mainland Japan before the typhoon swung back into the Pacific Ocean.

Although it cannot be known for certain, it is possible that the shearwater was capable of escaping from the typhoon but instead chose to ride it out until the storm moved back over the ocean. Like most birds adapted to a life at sea, streaked shearwaters typically fly at very low altitudes, an efficient flight strategy over the open ocean that also puts them at higher risk of collisions with buildings, power lines and vehicles when over land. Moreover, they are clumsy on solid ground, and if forced to land have difficulty taking off, rendering them highly vulnerable to predation.

Pelagic birds resort to a wide range of tactics to avoid being caught within the tumult of large storms. Red-footed boobies and great frigatebirds, for instance, often take to the wing and ascend to high altitudes, allowing storms to pass below, whereas Eastern brown pelicans simply sit them out, remaining grounded until conditions improve. Still others elect to stay within the eye of the storm, where winds are calmer.

Read more at Science Daily

Study suggests that having common ancestors can jeopardize fertility for generations

When it comes to the architecture of the human genome, it's only a matter of time before harmful genes -- genes that could compromise future generations -- arise in a population. These mutations accumulate in the gene pool, primarily affected by a population's size and practices like marrying within a small community, according to researchers.

But much of the information about the effects of a population's mutation load is based on genetic theory, with limited direct evidence concerning the effects on evolutionary fitness, or fertility.

New research from University of California, Davis, provides rare direct evidence showing that increased homozygosity -- meaning two identical alleles in a genome -- leads to negative effects on fertility in a human population. The paper was published Oct. 17 in the Proceedings of the National Academy of Sciences journal.

"People have known since Darwin that if you take people who are first cousins and they have children together, the children are more likely to develop certain diseases or be less healthy," said Brenna Henn, an associate professor of anthropology in the College of Letters and Science at UC Davis.

The research assesses the consequences of homozygosity among Namibia's Himba community, an isolated, agro-pastoralist population in which marriage between people with the same ancestor occurs. The research was led by Natalie Swinford, who received her doctoral degree in 2022 in evolutionary anthropology and human population genetics, and Henn.

"They're what we call an 'endogamous population,' meaning people are meeting their partners just from within that Himba group," said Henn. "They also have a unique system of marriage and reproduction, where men and women can have multiple boyfriends or girlfriends during their marriage. That means there are a lot of half-siblings in the population. That's a unique feature and it means that we can leverage that social structure to look at different genetic effects."

Echoes in the genome

In the study, the team gathered genetic data from 681 individuals from the Himba population. Genetic analyses revealed that the Himba have genetic markers that show higher levels of inbreeding.

Known as runs of homozygosity, or ROH, these markers are multiple and particularly long in the genomes of the analyzed Himba, which indicates that their parents had a high likelihood of sharing an ancestor.

While the Himba population has historically exhibited a preference for consanguinity, Henn and Swinford were surprised to find that none of the individuals in their sample population had parents who were actually first cousins. The lengths of the ROH in the genomes indicated otherwise.

The researchers found that these genetic effects can pool and accumulate over time. So, bottleneck events, like a decrease in population that leads to inbreeding, can have genetic echoes that don't manifest until generations later. The researchers concluded that such events occurred within the past 12 to 18 generations of the Himba population.

"People may not be full first-cousins," Henn said. "But they may be half-cousins once removed and then their grandparents might have been half-cousins. Anytime something like that happens, it's going to contribute to there being identical DNA in the offspring."

A negative effect on fertility

The Himba are a pronatalist community, meaning they encourage their members to have many children. Typically, there are short intervals between births, roughly between one and three years, researchers said.

To gauge the effects of long ROH on fertility, the researchers measured the reproductive success of post-reproductive women in their sample population. The researchers defined reproductive success as the number of children who survived to at least 5.

The research team used statistical models to analyze the relationship between the amount of ROH in the genome and the number of children a woman had. They found that the greater the proportion of the genome that was in ROH, the more likely a woman was to have fewer children than a woman who had less ROH.

"This means that a woman who has parents who are more related is more likely to have fewer children throughout her lifetime than a woman who has parents who are less related," said Swinford.

Read more at Science Daily

Oct 25, 2023

Astrophysicists scan the Galaxy for signs of life

Astrophysicists from Trinity College Dublin are scanning the Universe for "technosignatures" emanating from distant planets that would provide support for the existence of intelligent, alien life.

Using the Irish LOFAR telescope and its counterpart in Onsala, Sweden, the team -- led by Professor Evan Keane, Associate Professor of Radio Astronomy in Trinity's School of Physics, and Head of the Irish LOFAR Telescope -- plans to monitor millions of star systems.

Scientists have been searching for extraterrestrial radio signals for well over 60 years. Many of these have been carried out using single observatories which limits the ability to identify signals from the haze of terrestrial interference on Earth. Much of the effort has focused on frequencies above 1 GHz because the single-dish telescopes employed operate at these frequencies.

Now, a new collaboration led by Trinity College Dublin, with the Breakthrough Listen team and Onsala Space Observatory in Sweden, is perfecting a multi-site, multi-telescope technique that allows them to search at much lower frequencies of 110 -- 190 MHz.

The Breakthrough Listen programme is the most comprehensive search for technologically advanced extraterrestrial life, developing dedicated instruments at the Irish and Swedish LOFAR stations. Using multiple sites has the major benefit that it is much less likely to provide a "false positive" signal; such signals arise due to interference from many human sources on Earth.

The team has just published details of their method and their ongoing search in the Astronomical Journal They have already scanned 1.6 million star systems flagged as interesting targets by the Gaia and TESS space missions, run by ESA and NASA respectively. So far these searches have drawn a blank.

But the search has only just begun...

Prof. Keane said: "In the last 50 years evidence has steadily mounted that the constituents and conditions necessary for life are relatively common in the Universe, which begs one of life's greatest unanswered questions: are we really alone?

"To some people the 'Search for Extra-terrestrial Intelligence, or SETI' might seem like something from a movie, but it has been a scientific pursuit for decades, and for a host of very good reasons. With this project we are basing our search on the common assumption that civilisations elsewhere in the Universe may employ similar technologies to those developed on Earth. As a result radio frequencies are a logical domain for conducting SETI surveys due to the widespread use of telecommunications and radar and our access to next-gen radio telescopes offers a great chance for a deep dive into the Universe."

Owen Johnson, PhD Candidate in Trinity's School of Physics, is the first author of the journal article, and the first Irish person to ever undertake a PhD on the topic of SETI. He added:

"What makes surveys like this one truly captivating is the fact that we're pushing these telescopes to their absolute limits, directing them towards substantial portions of the sky. As a result, we have the exciting possibility of discovering all sorts of wild and wondrous phenomena during this process and if we're very fortunate, even encountering our cosmic neighbours.

"LOFAR is soon to undergo a staged series of upgrades across all stations in the array across Europe, which will allow an even broader SETI at ranges of 15 -- 240 MHz. We have billions of star systems to explore and will be relying on some machine learning techniques to sift through the immense volume of data.

Read more at Science Daily

Origin of ancient mummified baboons found in Egypt

In ancient Egypt, various deities were portrayed as animals. Thoth, the god of learning and wisdom was represented by a hamadryas baboon. Baboons, probably held in captivity in Egypt, were mummified as votive offerings after their deaths. Today, no wild baboons live in Egypt, and there is no evidence to suggest that these primates did so in the past. In an interdisciplinary project involving biologists, Egyptologists and anthropologists, Gisela Kopp, a biologist from Konstanz who conducts research on non-human primates, pursued the question of how and from where baboons came to Egypt. The results have been published in the current issue of the journal eLife.

Baboons were imported

To pay homage to the deity Thoth, baboons were probably imported from distant regions and kept in captivity in ancient Egypt. As studies of skeletons show, they had their dangerous canine teeth removed. To determine the geographic origin of the baboons, Gisela Kopp and her team used genetic analyses. The region from which the animals originate can be determined with the help of the mitochondrial genome of the animal mummies. The distribution of baboons across the African continent and their genetic diversity is well studied.

"We have comparative samples from almost all regions where baboons live today," Gisela Kopp says. These were supplemented with approximately 100 to 150-year-old specimens from museum collections. Comparisons of samples from the widely separated time periods are possible because the location of the different genetic variants of the baboon populations is very consistent over time.

Comparative sample points to Adulis

One of the study's collaborators, anthropologist Nathaniel Dominy from Dartmouth College in the United States, had already used stable isotopes to identify the respective geographic locations of mummified baboons. This method of using chemical signatures can be employed to distinguish between where animals were born and where they grew up. The study, published in 2020, was able to identify the Horn of Africa as the baboons' region of origin. Using genetic analysis, which has higher geographic precision and can also determine where the animals and their ancestors came from originally, the location was narrowed down to a well-defined area in Eritrea and neighbouring regions. A comparative sample that was most similar to the genetic variant of the mummy specimen originates from the coastal region in Eritrea, where, in ancient times, the port of Adulis was probably located. Ancient texts refer to Adulis as a trading place for luxury goods and animals.

The mummy specimen used by Gisela Kopp and her team was excavated in 1905 in the "Valley of the Monkeys" and is now held in the Musée des Confluences in Lyon. The mummy is estimated to date back to between 800 and 500 BCE in the Late Period of ancient Egypt. This is long before Adulis flourished as an important trading centre and port.

Early historical texts mention Punt as the baboons' place of origin, a legendary region from which Egypt imported luxury goods for centuries until early in the first millennium BCE. However, the exact location of Punt is unknown. "Egyptologists have long puzzled over Punt, since some scholars have seen it as a location in early global maritime trade networks, and thus the starting point for economic globalization," says Gisela Kopp.

Egyptology provides the link between Punt and Adulis

Punt is documented in ancient illustrations and texts from the same period as the mummy specimens. The Egyptological expertise in the project made it possible to link Punt to Adulis. "The specimen we studied fits chronologically with the last known expeditions to Punt. Geographically, however, it fits Adulis, a location that, centuries later, was known as a trading place, also for primates. We hypothesize that Punt and Adulis are two different names for the same place that were used at different points in time," Gisela Kopp says. And: "It was only after we put our biological findings in the context of historical research that the story really came together."

In the field of biology itself the findings are a scientific breakthrough, because it was the first time that ancient DNA from mummified non-human primates was analyzed successfully. This opens up opportunities to study, for example, the impact of human-wildlife interactions on genetic diversity and their role in the transmission of diseases. The contact ancient Egyptians had with exotic animals is evidence for early intensive interactions between wild animals and humans. The mass mummification of different animal species and primates is a very extraordinary cultural practice.

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Climate report: 'Uncharted territory' imperils life on Earth

An international coalition of climate scientists says in a paper published today that the Earth's vital signs have worsened beyond anything humans have yet seen, to the point that life on the planet is imperiled.

William Ripple, a distinguished professor in the Oregon State University College of Forestry, and former OSU postdoctoral researcher Christopher Wolf are the lead authors of the report, and 10 other U.S. and global scientists are co-authors.

"Without actions that address the root problem of humanity taking more from the Earth than it can safely give, we're on our way to the potential collapse of natural and socioeconomic systems and a world with unbearable heat and shortages of food and freshwater," Wolf said.

Published in BioScience, "The 2023 State of the climate report: Entering uncharted territory" notes that 20 of 35 planetary vital signs the authors use to track climate change are at record extremes.

The authors share new data illustrating that many climate-related records were broken by "enormous margins" in 2023, particularly those relating to ocean temperatures and sea ice. They also note an extraordinary Canadian wildfire season that produced unprecedented carbon dioxide emissions.

The report follows by four years the "World Scientists' Warning of a Climate Emergency" published by Ripple and collaborators in BioScience and co-signed by more than 15,000 scientists in 161 countries.

"Life on our planet is clearly under siege," Ripple said. "The statistical trends show deeply alarming patterns of climate-related variables and disasters. We also found little progress to report as far as humanity combating climate change."

Among the key numbers in the report:
 

  • Fossil fuel subsidies -- actions by governments that artificially lower the cost of energy production, raise the price received by producers or lower the price paid by consumers -- roughly doubled between 2021 and 2022, from $531 billion to just over $1 trillion.
  • Already this year wildfires in Canada have pumped more than 1 gigaton of carbon dioxide into the atmosphere, greater than Canada's total 2021 greenhouse gas emissions of 0.67 gigatons.
  • In 2023, there have already been 38 days with global average temperatures more than 1.5 degrees Celsius above pre-industrial levels. Until this year, such days were a rarity, the authors note.
  • The highest average Earth surface temperature ever recorded came this past July, and there's reason to believe it was the highest surface temperature the planet has seen in the last 100,000 years.


"As scientists, we are hugely troubled by the sudden increases in the frequency and severity of climate-related disasters," said Wolf, now a scientist with Corvallis-based Terrestrial Ecosystems Research Associates. "The frequency and severity of those disasters might be outpacing rising temperatures. By the end of the 21st century, as many as 3 to 6 billion people may find themselves outside the Earth's livable regions, meaning they will be encountering severe heat, limited food availability and elevated mortality rates."

The authors say policies are needed that take aim at the underlying issue of "ecological overshoot." When human demand on the Earth's resources is too large, the result in an array of environmental crises, including biodiversity decline. As long as humanity continues to put extreme pressure on the planet, any strategy that focuses only on carbon or climate will simply redistribute the pressure, they note.

"Our goal is to communicate climate facts and make policy recommendations," Ripple said. "It is a moral duty of scientists and our institutions to alert humanity of any potential existential threat and to show leadership in taking action."

The authors urge transitioning to a global economy that prioritizes human well-being and curtails overconsumption and excessive emissions by the rich. Specific recommendations include phasing out fossil fuel subsidies, transitioning toward plant-based diets, scaling up forest protection efforts and adopting international coal elimination and fossil fuel non-proliferation treaties.

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Raining cats and dogs: Global precipitation patterns a driver for animal diversity

Since the HMS Beagle arrived in the Galapagos with Charles Darwin to meet a fateful family of finches, ecologists have struggled to understand a particularly perplexing question: Why is there a ridiculous abundance of species some places on earth and a scarcity in others? What factors, exactly, drive animal diversity?

With access to a mammoth set of global-scale climate data and a novel strategy, a team from the Department of Watershed Sciences in Quinney College of Natural Resources and the Ecology Center identified several factors to help answer this fundamental ecological question. They discovered that what an animal eats (and how that interacts with climate) shapes Earth's diversity.

The work was recently published in the high-impact journal Ecology Letters.

"Historically studies looking at the distribution of species across Earth's latitudinal gradient have overlooked the role of trophic ecology -- how what animals eat impacts where they are found," said Trisha Atwood, author on the study from the Department of Watershed Sciences and the Ecology Center. "This new work shows that predators, omnivores and herbivores are not randomly scattered across the globe. There are patterns to where we find these groups of animals."

Certain locations have an unexpected abundance of meat-eating predators -- parts of Africa, Europe and Greenland. Herbivores are common in cooler areas, and omnivores tend to be more dominant in warm places. Two key factors emerged as crucial in shaping these patterns: precipitation and plant growth.

Precipitation patterns across time play a big role in determining where different groups of mammals thrive, Atwood said. Geographical areas where precipitation varies by season, without being too extreme, had the highest levels of mammal diversity.

"Keep in mind that we aren't talking about the total amount of rain," said Jaron Adkins, lead author on the research. "If you imagine ecosystems around the world on a scale of precipitation and season, certain places in Utah and the Amazon rainforest fall on one end with low variability -- they have steady levels of precipitation throughout the year. Other regions, like southern California, have really high variability, getting about 75 percent of the annual precipitation between December and March."

But the sweet spot for predators and herbivores fell in a middle zone between the two extremes, he said. Places like Madagascar, where precipitation patterns had an equal split between a wet season and a dry one (six months each), had the ideal ecological cocktail for promoting conditions for these two groups. Omnivore diversity tends to thrive in places with very stable climates.

The second important factor connected with mammal diversity the work uncovered was a measure of the amount of plant growth in an area, measured as "gross primary productivity."

"It makes intuitive sense for plant-eating animals to benefit from plant growth," Adkins said.

But this measure actually impacted carnivores most, according to the research. The strong relationship between predators and plant growth highlights the importance of an abundance of plants on an entire food chain's structural integrity.

"It was surprising that this factor was more important for predators than omnivores and herbivores," Atwood said. "Why this is remains a mystery."

Although evolutionary processes are ultimately responsible for spurring differences in species, climate conditions can impact related factors -- rates of evolutionary change, extinction and animal dispersal -- influencing species and trait-based richness, according to the research.

Animal diversity is rapidly declining in many ecosystems around the world through habitat loss and climate change. This has negative consequences for ecosystems. Forecasting how climate change will disrupt animal systems going forward is extremely important, Atwood said, and this research is a first step in better managing future conditions for animals around the world.

"Animal diversity can act as an alarm system for the stability of ecosystems," Atwood said. "Identifying the ecological mechanisms that help drive richness patterns provides insight for better managing and predicting how diversity could change under future climates."

Read more at Science Daily

Oct 24, 2023

Curiosity rover finds new evidence of ancient Mars rivers, a key signal for life

New analysis of data from the Curiosity rover reveals that much of the craters on Mars today could have once been habitable rivers.

"We're finding evidence that Mars was likely a planet of rivers," said Benjamin Cardenas, assistant professor of geosciences at Penn State and lead author on a new paper announcing the discovery. "We see signs of this all over the planet."

In a study published in Geophysical Research Letters, the researchers used numerical models to simulate erosion on Mars over millennia and found that common crater formations -- called bench-and-nose landforms -- are most likely remnants of ancient riverbeds.

The study was the first to map the erosion of ancient Martian soil by training a computer model on a combination of satellite data, Curiosity images and 3D scans of the stratigraphy -- or layers of rock, called strata, deposited over millions of years -- beneath the Gulf of Mexico seafloor. The analysis revealed a new interpretation for common Martian crater formations which, until now, have never been associated with eroded river deposits.

"We have everything to learn about Mars by better understanding how these river deposits can be interpreted stratigraphically, thinking about rocks today as layers of sediment deposited over time," Cardenas said. "This analysis is not snapshot, but a record of change. What we see on Mars today is the remnants of an active geologic history, not some landscape frozen in time."

Prior studies of satellite data from Mars had identified erosional landforms called fluvial ridges as being possible candidates for ancient river deposits. Using data collected by the Curiosity rover at Gale crater, the team found signs of river deposits that are not associated with fluvial ridges, but rather bench-and-nose landforms that have never been linked to ancient river deposits.

"This suggests that there could be undiscovered river deposits elsewhere on the planet, and that an even larger section of the Martian sedimentary record could have been built by rivers during a habitable period of Mars history," Cardenas said. "On Earth, river corridors are so important for life, chemical cycles, nutrient cycles and sediment cycles. Everything is pointing to these rivers behaving similarly on Mars."

In designing their computer model, Cardenas and his team found a new use for 25-year-old scans of Earth's stratigraphy. Collected by oil companies, the scans of beneath the Gulf of Mexico seafloor provided an ideal comparison to Mars, Cardenas explained.

The team simulated Mars-like erosion using the 3D scans of actual, recorded stratigraphy on Earth. When they ran the simulation, the model revealed erosional Martian landscapes that formed topographic benches and noses, rather than fluvial ridges, appearing almost identical to landforms observed by the Curiosity rover inside the Gale crater.

"Our research indicates that Mars could have had far more rivers than previously believed, which certainly paints a more optimistic view of ancient life on Mars," Cardenas said. "It offers a vision of Mars where most of the planet once had the right conditions for life."

Read more at Science Daily

The Moon is 40 million years older than previously thought

Led by researchers at the Field Museum and the University of Glasgow, the study was made possible by Northwestern University's atom-probe tomography facility, which "nailed down" the age of the oldest crystal in the sample. By revealing the age of these telltale zircon crystals -- found hidden within dust collected from the Moon -- researchers were able to piece together the timeline of the Moon's formation.

The study was published today (Oct. 23) in the journal Geochemical Perspectives Letters.

"This study is a testament to immense technological progress we have made since 1972 when the last manned Moon mission returned to Earth," said Northwestern's Dieter Isheim, who co-authored the study. "These samples were brought to Earth half-a-century ago, but only today do we have the necessary tools to perform microanalysis at the requisite level, including atom-probe tomography."

The atom-by-atom analysis enabled researchers to count how many atoms in the zircon crystals have undergone radioactive decay. When an atom undergoes decay, it sheds protons and neutrons to transform into different elements. Uranium, for example, decays into lead. Because scientists have established how long it takes for this process to unfold, they can assess the age of a sample by looking at the proportion of uranium and lead atoms.

"Radiometric dating works a little bit like an hourglass," said the Field Museum's Philipp Heck, the study's senior author. "In an hourglass, sand flows from one glass bulb to another, with the passage of time indicated by the accumulation of sand in the lower bulb. Radiometric dating works similarly by counting the number of parent atoms and the number of daughter atoms they have transformed to. The passage of time can then be calculated because the transformation rate is known."

Isheim is a research associate professor of materials science and engineering at Northwestern's McCormick School of Engineering and manager of Northwestern's Center for Atom-Probe Tomography (NUCAPT). David Seidman, the Walter P. Murphy Professor Emeritus of Materials Science and Engineering at McCormick and founding director of NUCAPT, also co-authored the study. Heck is the Field Museum's Robert A. Pritzker Curator for Meteorites and Polar Studies, senior director of the Negaunee Interactive Research Center and professor at the University of Chicago. Jennika Greer, a research associate professor at the University of Glasgow, is the study's lead author. When the research began, she was a Ph.D. candidate in Heck's laboratory.

More than 4 billion years ago, when the solar system was still young and the Earth was still growing, a giant Mars-sized object crashed into the Earth. A colossal hunk broke off Earth to form the Moon, and the energy of the impact melted the rock that eventually became the Moon's surface.

"When the surface was molten like that, zircon crystals couldn't form and survive," Heck said. "So, any crystals on the Moon's surface must have formed after this lunar magma ocean cooled. Otherwise, they would have been melted and their chemical signatures would be erased."

Because the crystals must have formed after the magma ocean cooled, determining the age of the zircon crystals would reveal the minimum possible age of the Moon. But, to pinpoint the maximum possible age of the Moon, researchers turned to Northwestern's atom-probe tomography instruments.

"In atom-probe tomography, we start by sharpening a piece of the lunar sample into a very sharp tip, using a focused ion beam microscope, almost like a very fancy pencil sharpener," Greer said. "Then, we use UV lasers to evaporate atoms from the surface of that tip. The atoms travel through a mass spectrometer, and how fast they move tells us how heavy they are, which in turn tells us what they're made of."

After determining the materials in the sample and performing radiometric dating, the researchers concluded that the oldest crystals are about 4.46 billion years old. That means the Moon must be at least that old.

It's important to know when the Moon formed, Heck said, because "the Moon is an important partner in our planetary system. It stabilizes the Earth's rotational axis. It's the reason there are 24 hours in a day. It's the reason we have tides. Without the Moon, life on Earth would look different. It's a part of our natural system that we want to better understand, and our study provides a tiny puzzle piece in that whole picture."

Read more at Science Daily

Superdeep diamonds provide a window on supercontinent growth

Diamonds contain evidence of the mantle rocks that helped buoy and grow the ancient supercontinent Gondwana from below, according to new research from a team of scientists led by Suzette Timmerman -- formerly of the University of Alberta and now at the University of Bern -- and including Carnegie's Steven Shirey, Michael Walter, and Andrew Steele. Their findings, published in Nature, demonstrate that superdeep diamonds can provide a window through space and time into the supercontinent growth and formation process.

For billions of years, Earth's landmasses have been ripped apart and smashed back together by plate tectonics, periodically forming giant supercontinents. This formation process results from large-scale convection of the planet's mantle. But the records of these events are poorly preserved, because the oceanic crust is young and continually sinks beneath the planet's surface by a process called subduction, while the continental crust only provides a limited view of Earth's deep workings.

Surprisingly, the research team was able to show that superdeep diamonds that formed between 300 and 700 kilometers below Earth's surface can reveal how material was added to the base of a once-mighty supercontinent.

"These diamonds allow us to see how deep plate tectonic processes relate to the supercontinent cycle," Shirey said.

The supercontinent Gondwana is thought to have formed between 800 and 550 million years ago in Neoproterozoic times. Starting over the present-day location of the South Pole, it incorporated the landmasses that make up present day South America, Africa, the Middle East, India, and Australia.

"By revealing the geological processes that contributed to Gondwana's growth, scientists can better understand the forces that shaped Earth's history and phenomenon of continental stability, which is -- of course -- fundamental to the eventual success of life on our planet," added Walter.

About 40 to 250 kilometers beneath the surface, geologic formations called mantle keels act as the foundation of the continental crust. The material that forms these keels thickened, stabilized, and cooled under the continental blocks to form strong, buoyant structures that can resist the relentless destructive forces of Earth's tectonic activity.

Remnants of the mantle rocks that helped form the keel can be found in tiny silicate and sulfide inclusions hidden inside these superdeep diamonds. Typically flaws in normal gem diamonds, these inclusions are the best friends of a geoscientist. They were identified, isolated, studied crystallographically, and then radiometrically dated to determine their geologic ages.

This work was carried out by researchers at the University of Alberta and the Carnegie Institution for Science, as well as by other teams of diamond specialists at the Vrije Universiteit Amsterdam, University of Bristol, and the University of Padua. It required many steps, including shipping the diamonds around the world several times, and deployed some of the most precise mass spectrometers and X-ray diffractometers available.

"The study of such rare samples with a variety of measurement techniques required major teamwork. But even more remarkable is how careful analyses of such minute amounts of material can shed light on the evolution of Earth's largest continental landmasses," Timmerman explained.

"The age of these inclusions provides a record of when buoyant mantle was added to Gondwana from below, thereby scaffolding, underpinning, and growing the supercontinent" added Shirey.

Then, about 120 million years ago, the supercontinent once buoyed by the rocks that housed these diamonds started to break up and, eventually, 30 million years later -- around 90 million years ago -- the diamonds -- and the inclusions trapped inside them -- were brought to the Earth's surface in violent volcanic eruptions of diamond-bearing kimberlite magma.

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Mummified mice discovered atop sky-high Andean volcanoes

They were the summits of 20,000-foot volcanoes. Amid the driest desert on Earth. Where temperatures never breached freezing, where less than half of sea-level oxygen quenched lungs, where gale-force winds scoured the hardscrabble rocks littering the peaks.

So when archaeologists first reported stumbling across a few mouse cadavers during expeditions to several Andean peaks in the 1970s and '80s, they figured, naturally, that the rodents must have hitched a ride with the Incas who once pilgrimaged a thousand-plus miles to what they considered sacred sites.

Those apexes served as altars for Capacocha, the ritual sacrifice of children to several Incan gods. Maybe, the thinking went, the mice had scurried into firewood or other supplies hauled up the slopes by the Incas. Or they were among the animal sacrifices that sometimes accompanied the human.

"You can't fault the archaeologists for thinking this way, because what other explanation is there?" said Jay Storz, a Willa Cather Professor of biological sciences at the University of Nebraska-Lincoln. "Nothing could be living up there, so they had to have been brought there."

But Storz would inadvertently cast doubt on the hypothesis in early 2020. Alongside friend and fellow mountaineer Mario Pérez Mamani, he captured a live specimen of leaf-eared mouse atop the 22,000-foot peak of Llullaillaco (zhoo-zhuh-ZHEYE'-koh), a volcano straddling the Chile-Argentina border. No mammal had ever been found living at such extreme altitude.

Alongside the capture of more live specimens, Storz and his colleagues have now reported the discovery of 13 leaf-eared mouse cadavers across the summits of three neighboring volcanoes -- Salín, Púlar and Copiapó -- that each stretch nearly 4 miles above sea level.

"These are basically freeze-dried, mummified mice," Storz said.

Analyzing the baker's dozen of mummies has only reinforced the team's conviction that the seemingly modest mice ascended the volcanoes without Incan assistance. By measuring concentrations of carbon-14, an atom that decays at a known rate, the team determined that the eight mummies atop Salín and one on Copiapó died no more than a few decades ago, likely after 1955. The four mummies on Púlar perished, at most, 350 years ago -- a full century after the last of the Incan empire fell to Spanish invaders.

"It now seems more and more clear," Storz said, "that the mice got there of their own accord."

The mummified state of the mice also helped preserve their DNA, allowing Storz's collaborators from the University of Montana to compare genetic variation among leaf-eared mice collected in the lowlands, midlands and highlands of Atacama Desert. Analyzing that variation across members of a species can help trace the evolutionary history of populations separated by distance, barriers or, in this case, altitude.

Storz and his colleagues wondered whether the genomes of the skyscraping, mummified mice might represent a distinct subpopulation of the leaf-eared rodent -- one with a colonization history different from that of their lower-dwelling peers.

"Our genomic data indicate no: that the mice from the summits, and those from the flanks or the base of the volcanoes in the surrounding desert terrain, are all one big happy family," Storz said, citing it as more evidence that the mummies were not hitchhikers but mountaineers.

In fact, the team found that two pairs of the leaf-eared mummies on Salín were closely related, possibly siblings or parents and offspring. And it noted another telltale: the equal ratio of males to females among the mummies. Combined with the recent discovery of other live specimens and mouse burrows in the heights of the Puna de Atacama, or Atacama Plateau, Storz said it seems that the leaf-eared mouse is not just touring the volcanic summits, but somehow living on them.

"It's exactly what you'd expect," he said, "if you were to capture a set of mice from some localized area in an environment that's habitable."

Which is bewildering, Storz said, given that the Puna de Atacama ranks among the most inhospitable locales on the planet -- one so arid, cold and oxygen-poor that NASA has visited the Atacama to practice searching for life on Mars.

"Even at the base of the volcanoes, the mice are living in an extreme, Martian environment," he said. "And then, on the summits of the volcanoes, it's even more so. It feels like outer space.

"It just boggles the mind that any kind of animal, let alone a warm-blooded mammal, could be surviving and functioning in that environment. When you experience it all firsthand, it even further impresses upon you: How in God's name is anything living up there?"

It's one of a few questions that the researchers are continuing to pursue. Members of Storz's lab and colleagues in Santiago, Chile, have since established colonies of leaf-eared mice collected from various altitudes. By acclimating each group to conditions that simulate the Puna de Atacama at 20,000 feet, the researchers hope to pinpoint whatever physiological adaptations are helping the rodents cope.

Even more fundamental is the question of what would drive the mice to such heights in the first place. Like most small rodents, the leaf-eared mouse -- which grows to about 2 ounces -- spends a fair amount of its time, energy and attention avoiding predators. And even in the Puna de Atacama, those predators are numerous: foxes, mountain lions, smaller cats, birds of prey.

Could the dangers imposed by the Atacama summits -- the near-absence of water, the seeming lack of food, the threat of freezing to death -- really be worth the promise of escaping predation all together?

"Certainly, if you're hunkering down on top of a 6,000-meter volcano, you're at least safe from that," Storz said. "You just have other things to worry about.

Read more at Science Daily

Oct 23, 2023

NASA's Webb discovers new feature in Jupiter's atmosphere

NASA's James Webb Space Telescope has discovered a new, never-before-seen feature in Jupiter's atmosphere. The high-speed jet stream, which spans more than 3,000 miles (4,800 kilometers) wide, sits over Jupiter's equator above the main cloud decks. The discovery of this jet is giving insights into how the layers of Jupiter's famously turbulent atmosphere interact with each other, and how Webb is uniquely capable of tracking those features.

"This is something that totally surprised us," said Ricardo Hueso of the University of the Basque Country in Bilbao, Spain, lead author on the paper describing the findings. "What we have always seen as blurred hazes in Jupiter's atmosphere now appear as crisp features that we can track along with the planet's fast rotation."

The research team analyzed data from Webb's NIRCam (Near-Infrared Camera) captured in July 2022. The Early Release Science program -- jointly led by Imke de Pater from the University of California, Berkeley and Thierry Fouchet from the Observatory of Paris -- was designed to take images of Jupiter 10 hours apart, or one Jupiter day, in four different filters, each uniquely able to detect changes in small features at different altitudes of Jupiter's atmosphere.

"Even though various ground-based telescopes, spacecraft like NASA's Juno and Cassini, and NASA's Hubble Space Telescope have observed the Jovian system's changing weather patterns, Webb has already provided new findings on Jupiter's rings, satellites, and its atmosphere," de Pater noted.

While Jupiter is different from Earth in many ways -- Jupiter is a gas giant, Earth is a rocky, temperate world -- both planets have layered atmospheres. Infrared, visible, radio, and ultraviolet light wavelengths observed by these other missions detect the lower, deeper layers of the planet's atmosphere -- where gigantic storms and ammonia ice clouds reside.

On the other hand, Webb's look farther into the near-infrared than before is sensitive to the higher-altitude layers of the atmosphere, around 15-30 miles (25-50 kilometers) above Jupiter's cloud tops. In near-infrared imaging, high-altitude hazes typically appear blurry, with enhanced brightness over the equatorial region. With Webb, finer details are resolved within the bright hazy band.

The newly discovered jet stream travels at about 320 miles per hour (515 kilometers per hour), twice the sustained winds of a Category 5 hurricane here on Earth. It is located around 25 miles (40 kilometers) above the clouds, in Jupiter's lower stratosphere.

By comparing the winds observed by Webb at high altitudes, to the winds observed at deeper layers from Hubble, the team could measure how fast the winds change with altitude and generate wind shears.

While Webb's exquisite resolution and wavelength coverage allowed for the detection of small cloud features used to track the jet, the complementary observations from Hubble taken one day after the Webb observations were also crucial to determine the base state of Jupiter's equatorial atmosphere and observe the development of convective storms in Jupiter's equator not connected to the jet.

"We knew the different wavelengths of Webb and Hubble would reveal the three-dimensional structure of storm clouds, but we were also able to use the timing of the data to see how rapidly storms develop," added team member Michael Wong of the University of California, Berkeley, who led the associated Hubble observations.

The researchers are looking forward to additional observations of Jupiter with Webb to determine if the jet's speed and altitude change over time.

"Jupiter has a complicated but repeatable pattern of winds and temperatures in its equatorial stratosphere, high above the winds in the clouds and hazes measured at these wavelengths," explained team member Leigh Fletcher of the University of Leicester in the United Kingdom. "If the strength of this new jet is connected to this oscillating stratospheric pattern, we might expect the jet to vary considerably over the next 2 to 4 years -- it'll be really exciting to test this theory in the years to come."

"It's amazing to me that, after years of tracking Jupiter's clouds and winds from numerous observatories, we still have more to learn about Jupiter, and features like this jet can remain hidden from view until these new NIRCam images were taken in 2022," continued Fletcher.

Read more at Science Daily

Increased West Antarctic Ice Sheet melting 'unavoidable'

Scientists ran simulations on the UK's national supercomputer to investigate ocean-driven melting of the West Antarctic Ice Sheet: how much is unavoidable and must be adapted to, and how much melting the international community still has control over through reduction of greenhouse gas emissions.

Taking into account climate variability like El Niño, they found no significant difference between mid-range emissions scenarios and the most ambitious targets of the 2015 Paris Agreement. Even under a best-case scenario of 1.5°C global temperature rise, melting will increase three times faster than during the 20th century.

The West Antarctic Ice Sheet is losing ice and is Antarctica's largest contributor to sea-level rise. Previous modelling finds this loss could be driven by warming of the Southern Ocean, particularly the Amundsen Sea region. Collectively the West Antarctic Ice Sheet contains enough ice to raise global mean sea-level by up to five metres.

Around the world millions of people live near the coast and these communities will be greatly impacted by sea level rise. A better understanding of the future changes will allow policymakers to plan ahead and adapt more readily.

Lead author Dr Kaitlin Naughten, a researcher at the British Antarctic Survey says:

"It looks like we've lost control of melting of the West Antarctic Ice Sheet. If we wanted to preserve it in its historical state, we would have needed action on climate change decades ago. The bright side is that by recognising this situation in advance, the world will have more time to adapt to the sea level rise that's coming. If you need to abandon or substantially re-engineer a coastal region, having 50 years lead time is going to make all the difference."

The team simulated four future scenarios of the 21st century, plus one historical scenario of the 20th century. The future scenarios either stabilised global temperature rise at the targets set out by the Paris Agreement, 1.5°C and 2°C, or followed standard scenarios for medium and high carbon emissions.

All scenarios resulted in significant and widespread future warming of the Amundsen Sea and increased melting of its ice-shelves. The three lower-range scenarios followed nearly identical pathways over the 21st century. Even under the best-case scenario, warming of the Amundsen Sea sped up by about a factor of three, and melting of the floating ice shelves which stabilise the inland glaciers followed, though it did begin to flatten by the end of the century.

The worst-case scenario had more ice shelf melting than the others, but only after 2045. The authors heed that this high fossil fuel scenario, where emissions increase rapidly, is considered unlikely to occur.

This study presents sobering future projections of Amundsen Sea ice-shelf melting but does not undermine the importance of mitigation in limiting the impacts of climate change.

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Researchers identify the oldest pieces of Baltic amber found on the Iberian Peninsula: imports began over 5,000 years ago

A team of scientists from the Universities of Granada and Cambridge, as well as the Government of Catalonia, have identified the oldest pieces of Baltic amber ever found on the Iberian Peninsula, revealing that this luxury material used in jewellery and handicrafts around the world was already being imported more than 5,000 years ago.

The research was led by UGR lecturer Mercedes Murillo-Barroso and involved the collaboration of Marcos Martinón-Torres of the University of Cambridge and Araceli Martín Cólliga of the Government of Catalonia. According to Murillo-Barroso, the work "allows us to say with confidence that the arrival of Baltic amber on the Iberian Peninsula occurred at least in the 4th millennium BC, more than a millennium earlier than we thought, and that it was probably part of wider trade networks linked to the south of France."

Trade is one of the many mechanisms through which we establish social relations, and often the objects that are exchanged are not necessarily consumer goods needed to live, but rather decorative, luxury or symbolic objects. Sometimes, especially in adverse conditions, having trade networks means having a network of mutual support, but these trade networks can also generate social inequalities and relations of dependency, especially if not all the community enjoys equal access to the networks or if the objects exchanged are unequal.

In prehistoric times, amber, a fossil resin, was certainly not a raw material necessary for the development of daily life, but it was highly valued and was exchanged via the extensive trade networks that were established. The use of the multiple amber deposits on the Iberian Peninsula since the Upper Palaeolithic has been documented and, thanks to research carried out by archaeologists over the years, we know that from the 4th millennium BC onwards Sicilian amber began to reach the Iberian Peninsula through Mediterranean trade networks. However, until now it was believed that Baltic amber did not reach the Peninsula until the 2nd millennium BC, at which point it would become the primary raw material, replacing other types of amber such as Peninsular or Sicilian amber.

Regarding their research article, published in the Nature journal Scientific Reports, Mercedes Murillo-Barroso affirms: "we present the standard infrared spectroscopy analysis of an amber bead of Baltic origin found at the Cova del Frare site in a context dated between 3634-3363 cal BC."

"The site, which is truly exceptional, illustrates the transition between the Middle Neolithic of the 'Sepulcrand the Late Neolithic of Véraza," explains Araceli Martín Cólliga, director of the excavations at the site.

"As there are no written documents from prehistoric times, the only way to study human activity is through archaeological remains. To study the transport and exchange of materials, we use very precise analytical techniques, such as infrared spectroscopy, which give us a kind of fingerprint of the amber deposits and objects," says Mercedes Murillo-Barroso.

Based on a large amount of data and this type of analysis, combined with other bodies of archaeological information, the study confirms that Baltic amber arrived in the northeastern Iberian Peninsula as early as the Neolithic, which is "something that must be understood in the context of trade during this period of transition and change, either by agents of a declining 'Sepulcres de Fossa' culture, or by those who would set new cultural trends at the end of the Neolithic, led by the Véraza groups of Catalonia and southern France, and not necessarily as direct contact with northern Europe." In fact, there is currently no evidence of Baltic amber crossing the Ebro at such an early date into the southern Iberian Peninsula, where the use of Sicilian amber was predominant as a result of the Mediterranean networks.

The Baltic region is home to what is perhaps the best amber in the world for use in jewellery. Indeed, it was highly sought after in classical Rome and now sustains a whole industry, for example in Poland. We now know that it began to arrive in Iberia as early as the 4th millennium BC, and that it gradually replaced Peninsular and Sicilian amber.

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Challenging prehistoric gender roles: Research finds that women were hunters, too

It's a familiar story to many of us: In prehistoric times, men were hunters and women were gatherers. Women were not physically capable of hunting because their anatomy was different from men. And because men were hunters, they drove human evolution.

But that story's not true, according to research by University of Delaware anthropology professor Sarah Lacy, which was recently published in Scientific American and in two papers in the journal American Anthropologist.

Lacy and her colleague Cara Ocobock from the University of Notre Dame examined the division of labor according to sex during the Paleolithic era, approximately 2.5 million to 12,000 years ago. Through a review of current archaeological evidence and literature, they found little evidence to support the idea that roles were assigned specifically to each sex. The team also looked at female physiology and found that women were not only physically capable of being hunters, but that there is little evidence to support that they were not hunting.

Lacy is a biological anthropologist who studies the health of early humans, and Ocobock is a physiologist who makes analogies between modern day and the fossil record. Friends in graduate school, they collaborated after "complaining about a number of papers that had come out that used this default null hypothesis that cavemen had strong gendered division of labor, the males hunt, females gather things. We were like, 'Why is that the default? We have so much evidence that that's not the case,'" Lacy said.

The researchers found examples of equality for both sexes in ancient tools, diet, art, burials and anatomy.

"People found things in the past and they just automatically gendered them male and didn't acknowledge the fact that everyone we found in the past has these markers, whether in their bones or in stone tools that are being placed in their burials. We can't really tell who made what, right? We can't say, 'Oh, only males flintknap,' because there's no signature left on the stone tool that tells us who made it," Lacy said, referring to the method by which stone tools were made. "But from what evidence we do have, there appears to be almost no sex differences in roles."

The team also examined the question of whether anatomical and physiological differences between men and women prevented women from hunting. They found that men have an advantage over women in activities requiring speed and power, such as sprinting and throwing, but that women have an advantage over men in activities requiring endurance, such as running. Both sets of activities were essential to hunting in ancient times.

The team highlighted the role of the hormone estrogen, which is more prominent in women than men, as a key component in conferring that advantage. Estrogen can increase fat metabolism, which gives muscles a longer-lasting energy source and can regulate muscle breakdown, preventing muscles from wearing down. Scientists have traced estrogen receptors, proteins that direct the hormone to the right place in the body, back to 600 million years ago.

"When we take a deeper look at the anatomy and the modern physiology and then actually look at the skeletal remains of ancient people, there's no difference in trauma patterns between males and females, because they're doing the same activities," Lacy said.

During the Paleolithic era, most people lived in small groups. To Lacy, the idea that only part of the group would hunt didn't make sense.

"You live in such a small society. You have to be really, really flexible," she said. "Everyone has to be able to pick up any role at any time. It just seems like the obvious thing, but people weren't taking it that way."

Man the Hunter

The theory of men as hunters and women as gatherers first gained notoriety in 1968, when anthropologists Richard B. Lee and Irven DeVore published Man the Hunter, a collection of scholarly papers presented at a symposium in 1966. The authors made the case that hunting advanced human evolution by adding meat to prehistoric diets, contributing to the growth of bigger brains, compared to our primate cousins. The authors assumed all hunters were male.

Lacy points to that gender bias by previous scholars as a reason why the concept became widely accepted in academia, eventually spreading to popular culture. Television cartoons, feature films, museum exhibits and textbooks reinforced the idea. When female scholars published research to the contrary, their work was largely ignored or devalued.

"There were women who were publishing about this in the '70s, '80s and '90s, but their work kept getting relegated to, 'Oh, that's a feminist critique or a feminist approach,'" Lacy said. "This was before any of the work on genetics and a lot of the work on physiology and the role of estrogen had come out. We wanted to both lift back up the arguments that they had already made and add to it all the new stuff."

Lacy said the "man the hunter" theory continues to influence the discipline. While she acknowledges that much more research needs to be done about the lives of prehistoric people -- especially women -- she hopes her view that labor was divided among both sexes will become the default approach for research in the future.

For 3 million years, males and females both participated in subsistence gathering for their communities, and dependence on meat and hunting was driven by both sexes, Lacy said.

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Oct 22, 2023

Black holes could come in 'perfect pairs' in an ever expanding Universe

Researchers from the University of Southampton, together with colleagues from the universities of Cambridge and Barcelona, have shown it's theoretically possible for black holes to exist in perfectly balanced pairs -- held in equilibrium by a cosmological force -- mimicking a single black hole.

Black holes are massive astronomical objects that have such a strong gravitational pull that nothing, not even light, can escape. They are incredibly dense. A black hole could pack the mass of the Earth into a space the size of a pea.

Conventional theories about black holes, based on Einstein's theory of General Relativity, typically explain how static or spinning black holes can exist on their own, isolated in space. Black holes in pairs would eventually be thwarted by gravity attracting and colliding them together.

However, this is true if one assumes the Universe is standing still. But what about one which is constantly moving? Could pairs of black holes exist in harmony in an ever expanding Universe, perhaps masquerading as one?

"The standard model of cosmology assumes that the Big Bang brought the Universe into existence and that, approximately 9.8 billion years ago, it became dominated by a mysterious force, coined 'dark energy', which accelerates the Universe at a constant rate," says Professor Oscar Dias of the University of Southampton.

Scientists refer to this mysterious force as a 'cosmological constant'. In a Universe explained by Einstein's theory with a cosmological constant, black holes are immersed in a cosmological accelerated background. This moves the theoretical goal posts over how black holes can interact and exist together.

Through complex numerical methods, the team behind this latest study show that two static (non-spinning) black holes can exist in equilibrium -- their gravitational attraction offset by the expansion associated with a cosmological constant. Even in the acceleration of an ever expanding Universe, the black holes remain locked at a fixed distance from one another. As hard as expansion may try to pull them apart, the gravitational attraction compensates.

"Viewed from a distance, a pair of black holes whose attraction is offset by cosmic expansion would look like a single black hole. It might be hard to detect whether it is a single black hole or a pair of them," comments Professor Dias.

Professor Jorge Santos of the University of Cambridge adds: "Our theory is proven for a pair of static black holes, but we believe it could be applied to spinning ones too. Also, it seems plausible that our solution could hold true for three or even four black holes, opening up a whole range of possibilities."

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Cobalt-free battery for cleaner, greener power

High-capacity and reliable rechargeable batteries are a critical component of many devices and even modes of transport. They play a key role in the shift to a greener world. A wide variety of elements are used in their production, including cobalt, the production of which contributes to some environmental, economic, and social issues. For the first time, a team including researchers from the University of Tokyo presents a viable alternative to cobalt which in some ways can outperform state-of-the-art battery chemistry. It also survives a large number of recharge cycles, and the underlying theory can be applied to other problems.

The chances are, you are reading this article on a laptop or smartphone, and if not, you probably own at least one of those. Inside either device, and many others, you will find a lithium-ion battery (LIB). For decades now, LIBs have been the standard way of powering portable or mobile electronic devices and machines. As the world transitions from fossil fuels, they are seen as an important step for use in electric cars and home batteries for those with solar panels. But just as batteries have a positive end and a negative end, LIBs have negative points set against their positive ones.

For one thing, although they are some of the most power-dense portable power sources available, many people wish that LIBs could yield a larger energy density to make them either last longer or power even more demanding machines. Also, they can survive a large number of recharge cycles, but they also degrade with time; it would be better for everyone if batteries could survive more recharge cycles and maintain their capacities for longer. But perhaps the most alarming problem with current LIBs lies in one of the elements used for their construction.

Cobalt is widely used for a key part of LIBs, the electrodes. All batteries work in a similar way: Two electrodes, one positive and one negative, promote the flow of lithium ions between them in what's called the electrolyte when connected to an external circuit. Cobalt, however, is a rare element; so rare in fact that there is only one main source of it at present: a series of mines located in the Democratic Republic of Congo. Many issues have been reported over the years about the environmental consequences of these mines, as well as the labor conditions there, including the use of child labor. From a supply perspective also, the source of cobalt is an issue due to political and economic instability in the region.

"There are many reasons we want to transition away from using cobalt in order to improve lithium-ion batteries," said Professor Atsuo Yamada from the Department of Chemical System Engineering. "For us the challenge is a technical one, but its impact could be environmental, economic, social and technological. We are pleased to report a new alternative to cobalt by using a novel combination of elements in the electrodes, including lithium, nickel, manganese, silicon and oxygen -- all far more common and less problematic elements to produce and work with."

The new electrodes and electrolyte Yamada and his team created are not only devoid of cobalt, but they actually improve upon current battery chemistry in some ways. The new LIBs' energy density is about 60% higher, which could equate to longer life, and it can deliver 4.4 volts, as opposed to about 3.2-3.7 volts of typical LIBs. But one of the most surprising technological achievements was to improve upon the recharge characteristics. Test batteries with the new chemistry were able to fully charge and discharge over 1,000 cycles (simulating three years of full use and charging), whilst only losing about 20% of their storage capacity.

"We are delighted with the results so far, but getting here was not without its challenges. It was a struggle trying to suppress various undesirable reactions that were taking place in early versions of our new battery chemistries which could have drastically reduced the longevity of the batteries," said Yamada. "And we still have some way to go, as there are lingering minor reactions to mitigate in order to improve the safety and longevity even further. At present, we are confident that this research will lead to improved batteries for many applications, but some, where extreme durability and lifespan are required, might not be satisfied just yet."

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Ancient sea monster remains reveal oldest mega-predatory pliosaur

The fossils of a 170-million-year-old ancient marine reptile from the Age of Dinosaurs have been identified as the oldest-known mega-predatory pliosaur -- a group of ocean-dwelling reptiles closely related to the famous long-necked plesiosaurs. The findings are rare and add new knowledge to the evolution of plesiosaurs. The study has been published in the journal Scientific Reports.

The fossils were found 40 years ago in north-eastern France. An international team of palaeontologists from the Naturkunde-Museum Bielefeld in Germany, the Institute of Paleobiology of the Polish Academy of Sciences in Warsaw, Poland, the Natural History Museum in Luxembourg and The Museum of Evolution at Uppsala University in Sweden have now analysed them and identified them as a new pliosaur genus: Lorrainosaurus.

Pliosaurs were a type of plesiosaur with short necks and massive skulls. They appeared over 200 million years ago, but remained minor components of marine ecosystems until suddenly developing into enormous apex predators. The new study shows that this adaptive shift followed feeding niche differentiation and the global decline of other predatory marine reptiles over 170 million years ago.

Lorrainosaurus is the oldest large-bodied pliosaur represented by an associated skeleton. It had jaws over 1.3 m long with large conical teeth and a bulky 'torpedo-shaped' body propelled by four flipper-like limbs.

"Lorrainosaurus was one of the first truly huge pliosaurs. It gave rise to a dynasty of marine reptile mega-predators that ruled the oceans for around 80 million years," explains Sven Sachs, a researcher at the Naturkunde-Museum Bielefeld, who led the study.

This giant reptile probably reached over 6 m from snout to tail, and lived during the early Middle Jurassic period. Intriguingly, very little is known about plesiosaurs from that time.

"Our identification of Lorrainosaurus as one of the earliest mega-predatory pliosaurs demonstrates that these creatures emerged immediately after a landmark restructuring of marine predator ecosystems across the Early-to-Middle Jurassic boundary, some 175 to 171 million years ago. This event profoundly affected many marine reptile groups and brought mega-predatory pliosaurids to dominance over 'fish-like' ichthyosaurs, ancient marine crocodile relatives, and other large-bodied predatory plesiosaurs," adds Daniel Madzia from the Institute of Paleobiology of the Polish Academy of Sciences, who co-led the study.

Pliosaurs were some of the most successful marine predators of their time.

"Famous examples, such as Pliosaurus and Kronosaurus -- some of the world's largest pliosaurs -- were absolutely enormous with body-lengths exceeding 10 m. They were ecological equivalents of today's Killer whales and would have eaten a range of prey including squid-like cephalopods, large fish and other marine reptiles. These have all been found as preserved gut contents," said senior co-author Benjamin Kear, Curator of Vertebrate Palaeontology and Researcher in Palaeontology at The Museum of Evolution, Uppsala University.

The recovered bones and teeth of Lorrainosaurus represent remnants of what was once a complete skeleton that decomposed and was dispersed across the ancient sea floor by currents and scavengers.

"The remains were unearthed in 1983 from a road cutting near Metz in Lorraine, north-eastern France. Palaeontology enthusiasts from the Association minéralogique et paléontologique d'Hayange et des environs recognised the significance of their discovery and donated the fossils to the Natural History Museum in Luxembourg," said co-author Ben Thuy, Curator at the Natural History Museum in Luxembourg.

Other than a brief report published in 1994, the fossils of Lorrainosaurus remained obscure until this new study re-evaluated the finds. Lorrainosaurus indicates that the reign of gigantic mega-predatory pliosaurs must have commenced earlier than previously thought, and was locally responsive to major ecological changes affecting marine environments covering what is now western Europe during the early Middle Jurassic.

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