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A 'beautiful' dinosaur tail found preserved in amber

Tail amber
© Current Biology
Feathered tail preserved in amber from North-Eastern Myanmar
The tail of a feathered dinosaur has been found perfectly preserved in amber from Myanmar. The one-of-a-kind discovery helps put flesh on the bones of these extinct creatures, opening a new window on the biology of a group that dominated Earth for more than 160 million years.

Examination of the specimen suggests the tail was chestnut brown on top and white on its underside. The tail is described in the journal Current Biology.

"This is the first time we've found dinosaur material preserved in amber," co-author Ryan McKellar, of the Royal Saskatchewan Museum in Canada, told the BBC News website.

The study's first author, Lida Xing from the China University of Geosciences in Beijing, discovered the remarkable fossil at an amber market in Myitkina, Myanmar.

The 99-million-year-old amber had already been polished for jewelry and the seller had thought it was plant material. On closer inspection, however, it turned out to be the tail of a feathered dinosaur about the size of a sparrow.

Better Earth

High-precision map reveals Antarctica's ice sheet bed topography

Antarctic
© Mathieu Morlighem / UCI
"Ultimately, BedMachine Antarctica presents a mixed picture: Ice streams in some areas are relatively well-protected by their underlying ground features, while others on retrograde beds are shown to be more at risk from potential marine ice sheet instability," says Mathieu Morlighem, UCI associate professor of Earth system science and lead author of the paper describing the newly released Antarctica bed topography map.
A University of California, Irvine-led team of glaciologists has unveiled the most accurate portrait yet of the contours of the land beneath Antarctica's ice sheet — and, by doing so, has helped identify which regions of the continent are going to be more, or less, vulnerable to future climate warming.

Highly anticipated by the global cryosphere and environmental science communities, the newly released Antarctica topography map, BedMachine, and related findings were published today in the journal Nature Geoscience.

Among the most striking results of the BedMachine project are the discovery of stabilizing ridges that protect the ice flowing across the Transantarctic Mountains; a bed geometry that increases the risk of rapid ice melting in the Thwaites and Pine Island glaciers sector of West Antarctica; a bed under the Recovery and Support Force glaciers that is hundreds of meters deeper than previously thought, making those ice sheets more susceptible to retreat; and the world's deepest land canyon below Denman Glacier in East Antarctica.

Comment: In Did Earth 'Steal' Martian Water?, Pierre Lescaudron's provides fascinating insight into Antarctica's unusual topography and ice cover:
Does the bedrock of Antarctica show any sign of positive electric scarring, i.e. a massive canyon-like geological feature? Indeed it does. As shown in the satellite picture above, Antarctica is considered to host the largest canyon on Earth, according to a 2016 geological survey:
[...] the largest unsurveyed region on the icy continent is a region called Princess Elizabeth Land. Now a team of geologists has scoured that area to reveal a massive subglacial lake and a series of canyons, one of which — more than twice as long as the Grand Canyon — could rank as Earth's largest.
[...]

The question then arises: why is there so much more ice in Antarctica compared to the Arctic? Why does Antarctica ice extend 2,500 meters below sea level and reach the bedrock, while Arctic ice is a mere 4 meter thick layer floating on the ocean?

[...]

In any case, no endogenous cause (snowfall difference, temperature difference) can explain the marked difference in depth and volume between the Antarctic ice sheet and the Arctic one. A massive and sudden inflow of exogenous water (in ice form) in Antarctica would, however, explain these discrepancies.
See also: And check out SOTT radio's:


Better Earth

1,000 mile long "Dark River" may be flowing beneath Greenland's ice

Greenland
© Chambers et al
The model on the right shows water flow in northern Greenland in the presence of a valley extending under glacial ice.
Far below the frozen cover of the Greenland ice sheet sprawls miles of bedrock — and extending through that bedrock for close to 1,000 miles (1,600 kilometers) is a valley that may contain a subterranean river, transporting water from central Greenland to the northern coast.

In the past, planes flying overhead had partially mapped a rocky, subsurface valley under the ice, but their radar coverage of the region left gaps, said Christopher Chambers, a researcher at Hokkaido University in Sapporo, Japan.

To build a clearer picture of what lurks below Greenland's surface, Chambers and his colleagues created simulations to explore the valley at different depths and model how water might melt from the surface of a glacier to the depths below — perhaps creating a flowing river, Chambers told Live Science. He presented their findings on Dec. 9 here at the annual meeting of the American Geophysical Union (AGU).

Comment: See also:


Jupiter

NASA's Juno spacecraft captures stunning photos of newly discovered Jovian tempest

Juno spacecraft Jupiter cyclone south pole
© Credits: NASA/JPL-Caltech/SwRI/ASI/INAF/JIRAM
A new, smaller cyclone can be seen at the lower right of this infrared image of Jupiter's south pole taken on Nov. 4, 2019, during the 23rd science pass of the planet by NASA's Juno spacecraft.
Jupiter's south pole has a new cyclone. The discovery of the massive Jovian tempest occurred on Nov. 3, 2019, during the most recent data-gathering flyby of Jupiter by NASA's Juno spacecraft. It was the 22nd flyby during which the solar-powered spacecraft collected science data on the gas giant, soaring only 2,175 miles (3,500 kilometers) above its cloud tops. The flyby also marked a victory for the mission team, whose innovative measures kept the solar-powered spacecraft clear of what could have been a mission-ending eclipse.

"The combination of creativity and analytical thinking has once again paid off big time for NASA," said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. "We realized that the orbit was going to carry Juno into Jupiter's shadow, which could have grave consequences because we're solar powered. No sunlight means no power, so there was real risk we might freeze to death. While the team was trying to figure out how to conserve energy and keep our core heated, the engineers came up with a completely new way out of the problem: Jump Jupiter's shadow. It was nothing less than a navigation stroke of genius. Lo and behold, first thing out of the gate on the other side, we make another fundamental discovery."

When Juno first arrived at Jupiter in July 2016, its infrared and visible-light cameras discovered giant cyclones encircling the planet's poles — nine in the north and six in the south. Were they, like their Earthly siblings, a transient phenomenon, taking only weeks to develop and then ebb? Or could these cyclones, each nearly as wide as the continental U.S., be more permanent fixtures?

Comment: Anomalous storms and turbulence have recently been reported on a number of planets:


Info

Study suggests genetics can predict a species' maximum lifespan

Wolly Mammoth
© AUSTRALIAN MUSEUM
A new “genetic clock” can reveal the lifespans of extinct species such as woolly mammoths.
"Would you want to know when you'll die?" has always been a hypothetical question - until now.

A study published in the journal Scientific Reports reveals that researchers from Australia's CSIRO and the University of Western Australia have figured out a way to tell how long a species' life clock will keep ticking.

"Our method for estimating maximum natural lifespan is based on DNA," says Ben Mayne, a postdoctoral fellow with CSIRO. "If a species' genome sequence is known, we can estimate its lifespan."

The "lifespan clock" screens 42 selected genes from short pieces of DNA in 252 vertebrate species. The density of these genes is correlated with lifespan to predict how long members of a given vertebrate species may live.

The authors suggest that their findings may inform research into the ecology and evolution of living and extinct species, the protection of threatened species, and sustainable fishing.

"Until now it has been difficult to estimate lifespan for most wild animals, particularly long-living species of marine mammals and fish," Mayne says.

When studying extinct animals, researchers used a species' descendant as reference.

Monkey Wrench

We need to know what happened to CRISPR twins Lulu and Nana

gene editing
© MS TECH Peggy Peterson
The unpublished research paper by He Jiankui about the creation of the babies shows proof of attempted gene editing gone awry.

It's been a year since He Jiankui announced that he'd made the world's first gene-edited human babies, twin girls with the pseudonyms Lulu and Nana. Widespread condemnation of his actions followed the announcement. But the facts of the case remain unclear, because he has not been transparent about his work.

In his single public appearance following his announcement, at the Second International Summit on Human Genome Editing in Hong Kong in November 2018, He presented his work by racing through about 60 slides in just 20 minutes. Although he showed data about what he had done to the twins' genes, it was blink-and-you'll-miss-it, and not enough to convince anyone of his claim that he'd safely edited the genomes of the human IVF embryos that became Lulu and Nana.

Comment: The CRISPR baby scandal gets worse by the day


Blue Planet

Granny killer whales pass along wisdom — plus extra fish — to their grandchildren

orca calf mother killer whale
© NOAA Fisheries
A mother orca and her calf near Port Renfrew, British Columbia.
Many human grandmothers love to spoil their grandchildren with attention and treats, and for good reason: Studies have shown that having a living grandmother increases a child's chance of survival. Now, new research shows the same may be true for killer whales. By providing young animals with some freshly caught salmon now and then — or perhaps with knowledge on where to find it — grannies increase their grand-offspring's chance of survival.

The new study is the first direct evidence in nonhuman animals of the "grandmother hypothesis." The idea posits that females of some species live long after they stop reproducing to provide extra care for their grandchildren.

"It's very cool that these long-lived cetaceans have what looks like a postfertile life stage," says Kristen Hawkes, an anthropologist at the University of Utah in Salt Lake City who has dedicated much of her career to studying the grandmother effect; she was not involved in the new study.

Fish

MBARI: Thousands of holes discovered on seafloor off California coast

Big Sur
© GlobalLookPress/ZUMAPRESS.com/Joanna Glikeson
Pacific Ocean, Big Sur, California
Researchers have discovered thousands of mysterious holes or pits in the seafloor — measuring 36 feet across and three feet deep on average — off Big Sur, California.

A team led by Eve Lundsten from the Monterey Bay Aquarium Research Institute (MBARI) discovered the so-called "micro-depressions" during a survey of North America's largest pockmark field.

Pockmarks are similar to micro-depressions albeit much larger, measuring around 600 feet across on average and 16 feet deep in this particular field. Since 1999, MBARI scientists have uncovered more than 5,200 of these almost-circular and evenly-spaced pockmarks across an area of around 500 square miles off Big Sur.
Pockmark locations
© 2019 MBARI
Pockmark locations
For their latest survey, the Lundsten and colleagues wanted to investigate this pockmark field because there are proposals to build a wind-energy farm in the area.

Info

Electrons flowing like water imaged for the first time

River of Electrons
© Weizmann Institute of Science
A “river” of electrons flowing in a graphene channel. The viscosity generated by the repulsion between electrons (red balls) causes them to flow with a parabolic current density, illustrated here as a white foam wavefront.
We often speak of electrons "flowing" through materials, but in fact, they do not normally move like a liquid. Such "hydrodynamic" electron flow had been predicted, though, and Weizmann Institute of Science researchers recently managed, with the help of a unique technique to image electrons flowing like the water flowing in a pipe. This is the first time such "liquid electron flow" has been visualized, and it has vital implications for future electronic devices.

Electrons usually move through conductors more like a gas thana liquid. That is, they do not collide with one another, but rather, they tend to bounce off impurities and imperfections in the material. A fluid flow, in contrast, takes it shape - be it waves or whirlpools - from frequent collisions between the particles in liquid.

To make electrons flow like a liquid, one needs a different kind of conductor, and the team turned to graphene, which is a one-atom-thick sheet of carbon, and which can be made exceptionally clean. "Theories suggest that liquid electrons can perform cool feats that their non-liquid counterparts cannot. But to get a clear-cut proof that electrons can, indeed, form a liquid state, we wanted to directly visualize their flow," said Prof. Shahal Ilani head of the team in the Institute's Condensed Matter Physics Department.

Fish

Predators may make prey get smart and grow more brain cells

fish
© U.S. Geological Survey, Bugwood.org
Where predators are common, this fish has more brain cells
Sometimes stress can be good for a fish. When there are more predators around, killifish in Trinidad grow more brain cells than those that face no predators, and they do so even into adulthood.

"I was surprised to find this because in previous studies, we found that predators inhibit the production of brain cells," says Kent Dunlap at Trinity College in Connecticut. It seems that killifish swim their own way.

Dunlap and his colleagues examined the brains of a type of wild caught killifish (Rivulus hartii) from three streams on the Caribbean island. In each stream, they gathered about eight adult fish from a location with a high number of predators and about eight from a location with little to no predation. They only used males because previous research on these fish showed that predation affects male but not female brains.

The researchers measured the size of the males' brains as well as the density of newly grown cells. They found that fish from both spots in each stream had brains similar in size relative to their bodies, but those that had to fight off more predators had nearly double the amount of new brain cells. Dunlap says this may mean that instead of fairly static brains that respond to predators in a timid way, the new brain cells could allow for more responsive behaviour.