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A giant sloth graveyard shows how these enormous animals died — and lived – CBC.ca

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An enormous pile of enormous bones excavated in Ecuador has given new insight into the behaviour of extinct giant ground sloths.  

Giant ground sloths lived in North and South America for millions of years until their extinction around the end of the last ice age — about 11,000 years ago. The largest species of giant ground sloths rivalled African elephants in size, and this new research suggests that their behaviour might have been very elephant-like as well.

“Between 10,000 and 50,000 years ago, depending on which continent you’re on, basically all ice-free continents had ecosystems that looked a lot more like a modern African ecosystem,” said researcher Emily Lindsey in an interview with Bob McDonald on Quirks & Quarks

“There were a lot of very large animals in that ecosystem and these sloths … were some of the largest.”

Seeping tar was the key to fossil preservation

Giant ground sloth remains have been found in many locations in the Americas, but the find at a site called Tanque Loma in Ecuador in the early 2000s was unique. First uncovered by an oil company during exploration, the site was a “tar seep” in which plant and animal remains had been sealed in naturally occurring tar.

The most famous similar site is Lindsey’s research home — she’s assistant curator and excavation site director at the La Brea Tar Pits in Los Angeles. But she said the preservation here is a little different.

Researcher Emily Lindsey at the excavation site in Ecuador surrounded by sloth bones. (Emily Lindsey)

“It’s a site that probably formed not through large animals getting actually trapped in the tar, but from an asphalt seep that arose after a bone bed was deposited, and just fortuitously preserved the bone bed in situ.”

Excavations over a period of nearly two decades revealed that the tar seep had preserved various plant and animal remains. The most notable were hundreds of bones from one of the largest species of giant sloth that ever lived, known scientifically as Eremotherium laurillardi, which survived as a species for about five million years.

Adults of this species weighed upward of three tonnes and could reach a length of up to six metres. They were ground dwelling herbivores who could feed on foliage high in tree tops by rearing up on their powerful hind legs.

Possibly a family group 

The excavated bones turned out to be from at least 22 individual animals, from small, dog-sized infants to full-sized adults. The context in which the bones were found suggested the animals died at roughly the same time, and also revealed the nature of the location.

“We believe that the site was a spring-fed marsh,” said Lindsey. “[It] probably had a lot of vegetation and it was probably an attractive area for large animals to come and spend time in [an] otherwise still somewhat arid tropical environment.”

La Brea Tar Pits staff and Ecuadoran students excavate and collect giant sloth bones at the Tanque Loma tar pit locality in Ecuador. (Emily Lindsey)

This seemed like a benign environment for giant sloths, so finding the remains of so many animals that had died at the same time was a mystery.

Fortunately the tar seep had preserved more evidence than bones. In and around the remains was a large amount of plant material — small branches, stems and twigs, all sharply cut into roughly 2.5-centimetre lengths.

At first Lindsey didn’t know what to make of this material. 

“It wasn’t until later when I was talking with a friend who is a retired professor of geography, and he told me a story that he had been monitoring a hippo wallow in Africa back in the ’70s,” she said.

Her colleague described how a drought had concentrated hippos around the small pond, and as a matter of course, the hippos defecated into it. A large amount of feces concentrated in the water. 

“It created this very unsanitary environment and thus this contributed to this rapid development of this disease that ended up wiping out their population,” she said.

Lindsey then realized that the characteristically shaped plant material she’d found associated with the sloth bones had probably been cut by their teeth, and was either gut contents or feces — a large amount of it.

Hippos congregate in large numbers in pools in Africa, contaminating them with feces. Observations of a die-off at such a pool inspired the idea that a group of ancient ground sloths might have died in a similar way. (Chris Dutton)

Contaminated water might have led to catastrophe

“At least a plausible explanation for how these animals died was something similar to what happened with this hippopotamus population that my co-author had observed in Africa,” Lindsey said.

Animals trapped by drought conditions near the shrinking wallow contaminated it, and this led to the mass death.

That meant they had a likely explanation for how the animals died. But more interesting was what the remains and the site said about how giant sloths lived.

“It’s not implausible to think, based on group situations that we see in other very large animals today, like elephants or other large savanna vertebrates, that there’s some sort of familial connection,” said Lindsey.

“These animals all died at a very similar time and were probably part of one large group. So they probably were social or gregarious animals.”


Written and produced by Jim Lebans

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See Astronaut's Sublime Shot of Total Lunar Eclipse Snapped From the ISS – CNET

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Earthlings on Earth weren’t the only ones who got to witness the lovely blushing of the “flower blood moon” total lunar eclipse on Sunday night and Monday morning. Residents of the International Space Station had a great view of the spectacular celestial event.

European Space Agency astronaut Samantha Cristoforetti shared a beautiful series of photos of the eclipse as seen from orbit. “A partially eclipsed moon playing hide-and-seek with our solar panel,” Cristoforetti tweeted on Monday.

The photos show the eclipse in progress, with the moon peeking under the station’s solar panels. One stunning view also shows Earth below, clouds visible against an expanse of blue. The images highlight the subtle shading of the moon as our planet threw its shadow across it.

Cristoforetti shared another look with just the eclipsed moon peeking over the curve of Earth.

Cristoforetti is an accomplished space photographer, having snapped plenty of gorgeous images during her last stay on the ISS in 2014 and 2015. Her most recent stint started in late April as part of NASA’s Crew-4 mission launched by SpaceX. 

I watched the eclipse last night from New Mexico. As the shadow moved across the moon, the ISS flew over, a bright bead of light crossing against the starry sky. So as I was seeing the ISS, Cristoforetti was likely tracking the eclipse, too. It doesn’t matter whether you’re on the ground or up in orbit, an eclipse is worth witnessing.

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NASA's InSight still hunting marsquakes as power levels diminish – Phys.org

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InSight captured this image of one of its dust-covered solar panels on April 24, 2022, the 1,211th Martian day, or sol, of the mission. Credit: NASA/JPL-Caltech

Dusty solar panels and darker skies are expected to bring the Mars lander mission to a close around the end of this year.

NASA’s InSight Mars lander is gradually losing power and is anticipated to end science operations later this summer. By December, InSight’s team expects the lander to have become inoperative, concluding a mission that has thus far detected more than 1,300 marsquakes—most recently, a magnitude 5 that occurred on May 4—and located quake-prone regions of the Red Planet.

The information gathered from those quakes has allowed scientists to measure the depth and composition of Mars’ crust, mantle, and core. Additionally, InSight (short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) has recorded invaluable weather data and studied remnants of Mars’ ancient magnetic field.

“InSight has transformed our understanding of the interiors of rocky planets and set the stage for future missions,” said Lori Glaze, director of NASA’s Planetary Science Division. “We can apply what we’ve learned about Mars’ inner structure to Earth, the Moon, Venus, and even rocky planets in other solar systems.”

InSight landed on Mars Nov. 26, 2018. Equipped with a pair of solar panels that each measures about 7 feet (2.2 meters) wide, it was designed to accomplish the mission’s primary science goals in its first Mars year (nearly two Earth years). Having achieved them, the spacecraft is now into an extended mission, and its solar panels have been producing less power as they continue to accumulate dust.

Because of the reduced power, the team will soon put the lander’s robotic arm in its resting position (called the “retirement pose”) for the last time later this month. Originally intended to deploy the seismometer and the lander’s heat probe, the arm has played an unexpected role in the mission: Along with using it to help bury the heat probe after sticky Martian soil presented the probe with challenges, the team used the arm in an innovative way to remove dust from the solar panels. As a result, the seismometer was able to operate more often than it would have otherwise, leading to new discoveries.

[embedded content]

NASA’s InSight Mars lander team speak about the mission’s science and the innovative ways they took on engineering challenges. During its time on Mars, InSight has achieved all its primary science goals and continues to hunt for quakes. Its mission is expected to conclude around the end of 2022. Credit: NASA/JPL-Caltech

When InSight landed, the produced around 5,000 watt-hours each Martian day, or sol—enough to power an electric oven for an hour and 40 minutes. Now, they’re producing roughly 500 watt-hours per sol—enough to power the same electric oven for just 10 minutes.

Additionally, seasonal changes are beginning in Elysium Planitia, InSight’s location on Mars. Over the next few months, there will be more dust in the air, reducing sunlight—and the lander’s energy. While past efforts removed some dust, the mission would need a more powerful dust-cleaning event, such as a “dust devil” (a passing whirlwind), to reverse the current trend.

“We’ve been hoping for a cleaning like we saw happen several times to the Spirit and Opportunity rovers,” said Bruce Banerdt, InSight’s principal investigator at NASA’s Jet Propulsion Laboratory in Southern California, which leads the mission. “That’s still possible, but energy is low enough that our focus is making the most of the science we can still collect.”

If just 25% of InSight’s panels were swept clean by the wind, the lander would gain about 1,000 watt-hours per sol—enough to continue collecting science. However, at the current rate power is declining, InSight’s non-seismic instruments will rarely be turned on after the end of May.

Energy is being prioritized for the lander’s seismometer, which will operate at select times of day, such as at night, when winds are low and marsquakes are easier for the seismometer to “hear.” The seismometer itself is expected to be off by the end of summer, concluding the science phase of the .

At that point, the lander will still have enough power to operate, taking the occasional picture and communicating with Earth. But the team expects that around December, will be low enough that one day InSight will simply stop responding.


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NASA’s InSight still hunting marsquakes as power levels diminish (2022, May 17)
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Peek-a-Boo Moon: Astronaut on Space Station Captures Spectacular Photos of the Lunar Eclipse – SciTechDaily

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ESA astronaut Samantha Cristoforetti captured pictures of the May 2022 lunar eclipse from the International Space Station.

On the evening of May 15, 2022, Earth passed between the Sun and the Moon blocking sunlight and casting a shadow on the lunar surface. ESA astronaut Samantha Cristoforetti witnessed this lunar eclipse from the International Space Station and captured it in a series of photographs.

During a lunar eclipse, Earth’s atmosphere scatters sunlight. The blue light from the Sun scatters away, and longer-wavelength red, orange, and yellow light pass through, turning our Moon red.

Lunar Eclipse From International Space Station 1

An image of a lunar eclipse as seen from the International Space Station. Credit: ESA-S.Cristoforetti

In these images, the Moon appears to play hide and seek with one of the International Space Station’s solar panels:

Lunar Eclipse From International Space Station 4

A partially eclipsed Moon playing hide and seek with the solar panel of the International Space Station. Credit: ESA-S.Cristoforetti

Lunar Eclipse From International Space Station 3

A partially eclipsed Moon playing hide and seek with the solar panel of the International Space Station. Credit: ESA-S.Cristoforetti

Lunar Eclipse From International Space Station 2

A partially eclipsed Moon playing hide and seek with the solar panel of the International Space Station. Credit: ESA-S.Cristoforetti

Samantha is living and working aboard the Space Station for her second mission, ‘Minerva’. Learn more about Samantha and the Minerva mission.

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