Painstaking study of 'Little Foot' fossil sheds light on human origins - Reuters

By Will Dunham

4 Min Read

(Reuters) - Sophisticated scanning technology is revealing intriguing secrets about Little Foot, the remarkable fossil of an early human forerunner that inhabited South Africa 3.67 million years ago during a critical juncture in our evolutionary history.

The skeleton of Little Foot is seen in Sterkfontein, South Africa, in this undated handout photo, obtained by Reuters on March 1, 2021. RJ Clarke/Handout via REUTERS

Scientists said on Tuesday they examined key parts of the nearly complete and well-preserved fossil at Britain’s national synchrotron facility, Diamond Light Source. The scanning focused upon Little Foot’s cranial vault - the upper part of her braincase - and her lower jaw, or mandible.

The researchers gained insight not only into the biology of Little Foot’s species but also into the hardships that this individual, an adult female, encountered during her life.

Little Foot’s species blended ape-like and human-like traits and is considered a possible direct ancestor of humans. University of the Witwatersrand paleoanthropologist Ron Clarke, who unearthed the fossil in the 1990s in the Sterkfontein Caves northwest of Johannesburg and is a co-author of the new study, has identified the species as Australopithecus prometheus.

“In the cranial vault, we could identify the vascular canals in the spongious bone that are probably involved in brain thermoregulation - how the brain cools down,” said University of Cambridge paleoanthropologist Amélie Beaudet, who led the study published in the journal e-Life.

“This is very interesting as we did not have much information about that system,” Beaudet added, noting that it likely played a key role in the threefold brain size increase from Australopithecus to modern humans.

Little Foot’s teeth also were revealing.

Slideshow ( 4 images )

“The dental tissues are really well preserved. She was relatively old since her teeth are quite worn,” Beaudet said, though Little Foot’s precise age has not yet been determined.

The researchers spotted defects in the tooth enamel indicative of two childhood bouts of physiological stress such as disease or malnutrition.

“There is still a lot to learn about early hominin biology,” said study co-author Thomas Connolley, principal beamline scientist at Diamond, using a term encompassing modern humans and certain extinct members of the human evolutionary lineage. “Synchrotron X-ray imaging enables examination of fossil specimens in a similar way to a hospital X-ray CT-scan of a patient, but in much greater detail.”

Little Foot, whose moniker reflects the small foot bones that were among the first elements of the skeleton found, stood roughly 4-foot-3-inches (130 cm) tall. Little Foot has been compared in importance to the fossil called Lucy that is about 3.2 million years old and less complete.

Both are species of the genus Australopithecus but possessed different biological traits, just as modern humans and Neanderthals are species of the same genus - Homo - but had different characteristics. Lucy’s species is called Australopithecus afarensis.

“Australopithecus could be the direct ancestor of Homo - humans - and we really need to learn more about the different species of Australopithecus to be able to decide which one would be the best candidate to be our direct ancestor,” Beaudet said.

Our own species, Homo sapiens, first appeared roughly 300,000 years ago.

The synchrotron findings build on previous research on Little Foot.

The species was able to walk fully upright, but had traits suggesting it also still climbed trees, perhaps sleeping there to avoid large predators. It had gorilla-like facial features and powerful hands for climbing. Its legs were longer than its arms, as in modern humans, making this the most-ancient hominin definitively known to have that trait.

“All previous Australopithecus skeletal remains have been partial and fragmentary,” Clarke said.

Reporting by Will Dunham in Washington, Editing by Rosalba O’Brien

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Engine shutdown led to failed Falcon 9 booster landing - SpaceNews

WASHINGTON — A Falcon 9 first stage failed to land after a launch last month because one of its engines shut down during flight after hot gas breached a worn-out cover.

During a NASA press conference March 1 about the upcoming Crew-2 commercial crew flight, Benji Reed, senior director for human spaceflight programs at SpaceX, said that while the booster used on that Feb. 15 launch was making its sixth flight, some components on it were “life leaders” that had flown more often than any other in the Falcon 9 fleet.

That included “boots,” or covers around parts of the Merlin engines in the first stage. “This was the highest count number of flights that this particular boot design had seen,” he said.

However, one of those boots had a “little bit of a hole” that allowed hot gas to get into parts of the engine during flight, he said. “A little bit of hot gas got to where it’s not supposed to be, and it caused that engine to shut down,” he said.

Reed didn’t mention at what point in the launch the engine shut down, but he suggested it took place during ascent. “A great thing about Falcon 9 is that we have engine-out capability,” he said, meaning that one of the first stage’s nine engines can shut down without jeopardizing the mission. “The vehicle got to orbit and put the satellites exactly where they want to be. The primary mission was accomplished.”

The shutdown of the engine, though, kept the first stage from landing. “When that booster came to return home, because of the problem with that particular engine, we didn’t have enough thrust to get back to where we needed to be, and didn’t land where we wanted to be,” he said.

Reed’s comments offered the most details to date on why the booster failed to land, breaking a streak of two dozen consecutive landings dating back nearly a year. Hans Koenigsmann, a longtime SpaceX executive who is currently a senior adviser for build and flight reliability at the company, said Feb. 23 that “heat damage” was to blame, but didn’t go into more details.

The Falcon 9 has not launched since that Feb. 15 mission, although the company attempted a launch Feb. 28 of another set of Starlink satellites. The launch was scrubbed 84 seconds before the scheduled 8:37 p.m. Eastern liftoff, and the company has not set a new date for the launch or provided more information about the cause of the scrub.

During the webcast of that launch attempt, the SpaceX hosts did not discuss the failed landing. However, they noted that there would be no video from the first stage on that launch, a break with the company’s standard practices.

Reed said the engine problem was “a great lesson that we learned” as the company works to better understand the lifetime of Falcon 9 boosters and which components are most susceptible to wear and tear. The company is also working to upgrade control systems on the vehicle “to even further detect and control what the vehicle needs to do” in circumstances like that.

NASA has been following the investigation to understand if there are any problems that may pose safety issues to the Falcon 9 that will launch the Crew-2 mission, currently scheduled for no earlier than April 20. “We will follow along with SpaceX’s investigation,” Steve Stich, manager of NASA’s commercial crew program, said at the briefing, including making sure they understand the problem before giving approval to launch the mission.

A big difference between the Starlink missions and Crew-2 is the number of flights. “We’re about to embark on our first reuse here for a crewed vehicle,” he said. The Falcon 9 booster that will launch Crew-2 previously launched the Crew-1 mission in November 2020, but with no flights in between. “SpaceX Starlink flights are pretty far out there” in terms of number of reuses of the boosters, he noted.

The astronauts who will fly on Crew-2 have also been keeping track of this and potentially other Falcon 9 issues. “We’ve been briefed about every month on the updates of our spacecraft as well as the rocket, so we’re very confident that they’re going to figure out what’s going wrong.” said Shane Kimbrough, the NASA astronaut who will command Crew-2. “It’s just been a few little things on a few of these rockets.” He didn’t elaborate on what those “few little things” are.

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Boeing Starliner test flight postponed - FRANCE 24

Issued on: 02/03/2021 - 02:28Modified: 02/03/2021 - 02:26

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Washington (AFP)

An unmanned test mission of Boeing's Starliner space capsule, which is eventually to transport astronauts to the International Space Station, has had to be postponed, NASA said Monday.

The test, which had previously been postponed until early April, will suffer another delay, this time due to unprecedented cold temperatures in Texas that caused extensive power outages in the southern US state.

"We did lose time with the weather in Houston. We lost about a week of time," said Steve Stich, the manager of NASA's Commercial Crew Program, during a press conference.

NASA is "continuing to evaluate options" for the new test date.

The Starliner's first crewed flight is currently scheduled for September, Stich added.

During an initial test flight in December 2019, the Starliner capsule failed to dock at the ISS and returned to Earth prematurely -- a setback for aerospace giant Boeing.

Since then, its program has fallen far behind SpaceX, the other company -- owned by Tesla CEO Elon Musk -- chosen by NASA to develop a vessel to transport astronauts to the ISS.

SpaceX's Crew Dragon capsule already carried astronauts to the station in June and November 2020. Four other astronauts, including Frenchman Thomas Pesquet, will return to the ISS in April.

© 2021 AFP

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'Fireball' meteor spotted across England thanks to clear skies - The Telegraph

[unable to retrieve full-text content]

1. 'Fireball' meteor spotted across England thanks to clear skies  The Telegraph
2. Meteor Streaks Like a Firework Across U.K. Night Sky  The New York Times
3. Giant METEOR flashes over UK rooftops 'like a firework'  The Sun
4. Meteorites may be just north of Cheltenham  BBC News
5. Fireball Meteor Streaks Across Night Sky Over U.K.  Bloomberg Quicktake: Now
6. View Full Coverage on Google News

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Neanderthals Listened to the World Much Like Us - The New York Times

A reconstructed Neanderthal ear adds a new piece to the puzzle of whether the early humans could speak.

If you were somehow able to travel back in time some 130,000 years and chance upon a Neanderthal, you might find yourself telling them about some of humanity’s greatest inventions, such as spanakopita and TikTok. The Neanderthal would have no idea what you were saying, much less talking about, but they might be able to hear you perfectly, picking up on the voiceless consonants “t,” “k” and “s” that appear in many modern human languages.

A team of scientists has reconstructed the outer and middle ear of Neanderthals and concluded that they listened to the world much like we do. Their study, published Monday in Nature Ecology & Evolution, found that Neanderthals had the anatomical ability to perceive a similar range of sounds as modern Homo sapiens, including upper speech frequencies that mainly involve consonant production.

The authors believe this research has implications beyond the ear. Any insight into how Neanderthals heard can offer new clues into one of the most-debated, unresolved questions about the ancient hominids: whether Neanderthals spoke.

Hearing and speech are often coupled in the animal kingdom, according to Dan Dediu, a language scientist at the Lumière University Lyon 2 in France, who was not involved with the research. “It would be meaningless for an animal to produce a frequency that can’t be heard by conspecifics,” he said.

The study offers new evidence that Neanderthals may have had some kind of recognizable spoken language, according to Sverker Johansson, a researcher at Dalarna University who was not involved with the research. “It is satisfying to find further confirmation that Neanderthals really were Neander-talkers,” Dr. Johansson wrote in an email.

For decades, the debate hinged on a single Neanderthal bone: the horseshoe-shaped hyoid, which is a key to speaking. The hyoid, which sits in the vocal tract, is small, fragile and not connected to any other bone. The only complete Neanderthal hyoid was recovered from a skeleton in a cave in Israel in the 1980s, and its striking similarity to a human hyoid led to a flurry of attempts to reconstruct the Neanderthal voice box and vocal tract.

But it is difficult to draw sweeping conclusions from a single fossilized bone, let alone one untethered from the skeleton and no longer held aloft with long-lost soft tissues. “You don’t get a lot of preserved Neanderthal tongues,” said Anna Goldfield, an anthropologist and host of “The Dirt” podcast.

So some scientists took a different approach. Twenty years ago, Ignacio Martínez, a paleontologist at the University of Alcalá in Spain and an author on the study, had an odd idea: to study the evolution of language by reconstructing hearing in early humans.

“It was a harebrained, and also kind of brilliant idea,” said Rolf Quam, a paleoanthropologist at Binghamton University and an author on the study, who was working with Dr. Martínez as a graduate student at the time. The researchers didn’t know if they would be able to reconstruct a Neanderthal ear — no one had done it before — but spent the next two decades developing, testing and retesting ear models.

In the new study, the researchers used high-resolution CT scans of ear structures in five Neanderthals, 10 modern Homo sapiens and nine early hominids from Sima de los Huesos, an archaeological site in what is now Spain, who lived before Neanderthals.

The team created 3-D models of these ear structures and ran the measurements through a software model to calculate the sound power transmission, which describes the way sound energy moves from the environment into the ear canal and winds its way toward the cochlea — essentially how much of the sound energy ultimately makes it to your inner ear.

The researchers used this metric to calculate the occupied bandwidth, which reflects the range of frequencies in which at least 90 percent of the sound power reaches the inner ear — the “sweet spot” of hearing, according to Dr. Quam. This sweet spot is the range we hear best in, where our ears are most tuned to sound.

Three-dimensional reconstruction of the external auditory canal (green), middle ear cavity (blue) and mastoid air cells (purple/gray) in Neanderthals.Conde-Valverde et al., Nature Ecology & Evolution 2021

The study found the Neanderthal ear’s sweet spot extended toward frequencies of 3 to 5 kHz, which are specifically dedicated to consonant production. The researchers believe this optimization toward consonants could be a key sign that Neanderthals had verbal language.

“The use of consonants distinguishes human language from mammalian communication, which is almost completely vowels,” Dr. Quam said. “Like grunts, howls, shrieks.”

In fact, the study found Neanderthals’ sweet spot was the same as modern human hearing, whereas the early hominids from Sima de los Huesos had a hearing range somewhere between chimpanzees and modern humans.

According to the researchers’ calculations, Neanderthals most likely would have been able to hear voiceless consonants that are produced without the vocal cords. These included voiceless stops, such as “t” and “k,” and voiceless fricatives including “f,” “s” and “th.” Voiceless consonants cannot be broadcast loudly throughout a landscape — try screaming “ththth” or “sssss” — which could indicate that these consonants were used for close-by communication between members of the same species.

Even though Neanderthals had all the right anatomy to support human speech, the authors concede that Neanderthals’ physical ability does not imply mental ability, or the cognition required for human language.

“Speech isn’t necessary for language,” said Robert Berwick, a computational linguist at the Massachusetts Institute of Technology who was not involved with the study. Dr. Berwick was not convinced of the authors’ interpretation of what the reconstructed ear indicates about Neanderthal communication; in his view, the Neanderthals’ consonant-friendly sweet spot does not imply an ability to acquire human language. “If we evolved with differently shaped ears, then we’d simply make different use of the contrasts we’re still able to perceive,” he said.

The question of Neanderthal speech may never be fully resolved, even as evidence continues to accumulate. “There are no Neanderthals left to speak,” Dr. Goldfield said.

Numerous recent discoveries around the nature of Neanderthal life present a compelling case that they behaved symbolically, wearing jewelry, making cave art and burying their dead. These revelations have helped emancipate Neanderthals from the longstanding perception that the early humans were primitive brutes, a myth partly rooted in racist ideology.

For a long time, scientists tended to think there was a “jump” that separated modern humans from the rest of the biological world, such as cognition and language, according to Dr. Dediu. “But Neanderthals were probably just as human as us, just in a different way,” he said.

The most striking evidence of Neanderthal interiority lies at the back of Bruniquel Cave in France, where archaeologists found two concentric rings of broken stalagmites, traces of fire and burned bones. The stalagmites had been snapped off 176,500 years ago — a time when Neanderthals were the only humans in the area.

The intentionality of the act suggests that the site was special in some way to Neanderthals. “I’m an empiricist, and unwilling to go beyond what the evidence says, but it baffles me to think they wouldn’t have had a spoken language,” Dr. Goldfield said.

When Dr. Quam began studying Neanderthals, he visited the ear-bone fossils at museums and measured them by hand, with calipers; some of the Neanderthals included in this study he first encountered years ago in France and Israel. CT scans now make it possible to understand the fossils on a much deeper level, but Dr. Quam says it still helps to see fossils in real life as he continues to research how Neanderthals might have spoken.

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Argentine titanosaur may be oldest yet: study - Al Jazeera English

The 20-metre lizard, discovered in Argentina in 2014, roamed what is now Patagonia some 140 million years ago.

A colossal dinosaur dug up in Argentina could be the oldest titanosaur ever found, having roamed what is now Patagonia some 140 million years ago at the beginning of the Cretaceous period, scientists said on Sunday.

The 65-foot (20-metre) lizard, Ninjatitan zapatai, was discovered in 2014 in the Neuquen province of southwest Argentina, the La Matanza University reported in its analysis.

“The main importance of this fossil, apart from being a new species of titanosaur, is that it is the oldest recorded for this group worldwide,” a statement quoted researcher Pablo Gallina of the Conicet scientific council as saying.

Titanosaurs were members of the sauropod group – gigantic plant-eating lizards with long necks and tails that may have been the largest animals ever to walk the Earth.

The new discovery, the statement said, meant titanosaurs lived longer ago than previously thought – at the beginning of the Cretaceous period that ended with the demise of the dinosaurs some 66 million years ago.

Fossils from 140 million years ago are “really very scarce” said Gallina, main author of a study published in the Argentinian scientific journal Ameghiniana.

The creature was named after Argentinian paleontologist Sebastian Apesteguia, nicknamed “El Ninja”, and technician Rogelio Zapata.

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Perseverance Seen From Space by ESA’s ExoMars Orbiter - Universe Today

A little over a week ago (February 18^th, 2021), NASA’s Perseverance rover landed in the Jezero crater on the surface of Mars. In what was truly a media circus, people from all over the world tuned to watch the live coverage of the rover landing. When Perseverance touched down, it wasn’t just the mission controllers at NASA who triumphantly jumped to their feet to cheer and applaud.

In the days that followed, the world was treated to all kinds of media that showed the surface of Mars and the descent. The most recent comes from the Trace Gas Orbiter (TGO), which is part of the ESA-Roscosmos ExoMars program. From its vantage point, high above the Martian skies, the TGO caught sight of Perseverance in the Jezero crater and acquired images that show the rover and other elements of its landing vehicle.

Since 2016, the TGO has orbited Mars and gathered vital data on the composition of its atmosphere. Specifically, TGO has been looking for traces of atmospheric methane and other gases that could be the result of geological or biological activity. These efforts are part of a larger effort to determine if life existed on Mars billions of years ago (and whether or not it still does).

Image of Perseverance and mission elements, as captured by the orbiter’s CaSSIS camera on Feb. 23rd, 2021. Credit: ESA

In addition, the orbiter has conducted other important scientific operations, like relaying data from robotic missions on the surface and acquiring images of space. On February 23^rd, the TGO took advantage of its orbit to snap pictures with its Colour and Stereo Surface Imaging System (CaSSIS) that showed the Perseverance rover – as well as its parachute, heat shield, and descent stage elements – within the Jezero crater.

In the first image (above), the elements are discernible as a series of dark and bright pixels, which are indicated in the second image (below). As you can see, the descent stage and heatshield are dark spots spaced around two smaller craters while the parachute and backshell are visibly bright spots in close proximity to each other. The Perseverance rover, near the bottom center, is a relatively faint spot by a small ridge leading from one crater.

It is here that Perseverance will spend the next two years (which will likely be extended) searching for signs of past microbial life. Based on its features, which include a preserved river delta and clay-rich sedimentary deposits, the Jezero crater is known to have hosted a standing body of water billions of years ago. For this reason, it was selected as the landing site for the mission, since it is believed to be a good place to find evidence of past life.

Perseverance will also conduct an ambitious and unprecedented operation, where it will collect samples of Martian rocks and soil and set them aside in a cache. These will be returned to Earth by a separate ESA-NASA Mars Sample Return mission that will consist of a lander, a rover (to retrieve the samples), and small launcher (for launching them to orbit). Once there, an orbiter will pick them up and bring them home for analysis.

Close-up of the images taken by the TGO of Perseverance and mission elements in the Jezero crater. Credit: ESA

The ExoMars TGO also provided a significant amount of assistance for the Perseverance rover during its landing, such as data relay services. Videos of the landing, as well as imagery and sound recordings, were captured by instruments aboard the rover’s Entry, Descent, and Landing (EDL) vehicle. These were sent back to Earth with the assistance of the TGO, as well as NASA’s Mars Reconnaissance Orbiter (MRO).

The orbiter will continue to provide data relay support between Earth and Mars for future missions to the surface, particularly the the next ExoMars mission. Known as ExoMars 2022, this mission will launch from the Baikonur Cosmodrome on Sept. 20^th, 2022, and arrive at the Red Planet by June 10^th, 2023. It will consist of the Russian Kazachok surface platform and the Rosalind Franklin rover.

Meanwhile, the Trace Gas Orbiter will continue to orbit Mars and conduct its own science operations, focusing on the analysis of Mars’ atmosphere and the search for gases that point the way towards past (or present) life. Recently, the orbiter detected traces of hydrogen chloride gas leaving the planet’s atmosphere, indicating that this salt exists on the surface which made it to orbit.

On Earth, this process has been observed with sodium chloride salts, where salt water evaporates from our oceans and is pushed into the upper atmosphere by strong winds. The TGO has also monitored water vapor leaving the Martian atmosphere and escaping to space. Together, these findings have provided new clues as to where the abundant surface water Mars had billions of years ago escaped to.

Orbital picture of the Jezero crater, showing its fossil river delta. Credit: NASA/JPL/JHUAPL/MSSS/BROWN UNIVERSITY

Further Reading: ESA

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