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Flowing water filled Gale Crater on Mars: Indian-origin scientist

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Washington: Around 3.3-3.8 billion years ago, a series of streams and lakes existed on the Red Planet, filling the Gale Crater with sediment deposited as layers that formed the foundation for the mountain named Mouth Sharp, an Indian-origin scientist has revealed.

According to Ashwin Vasavada, project scientist with NASA’s Mars Science Laboratory (MSL), the Red Planet appears to have had a more massive atmosphere billions of years ago than it does today, with an active hydrosphere capable of storing water in long-lived lakes.

The MSL team has concluded that this water helped to fill Gale Crater, Curiosity’s landing site.

“Observations from Curiosity rover suggest that a series of long-lived streams and lakes existed at some point in the past, delivering sediment that slowly built up the lower layers of Mount Sharp,” explained Vasavada.

Using Curiosity data, MSL scientists have pieced together an increasingly coherent and compelling story about the evolution of this region of Mars.

Before Curiosity landed on Mars, scientists proposed that Gale Crater had filled with layers of sediments.

Some hypotheses implied that the sediments accumulated from wind-blown dust and sand whereas others focused on the possibility that sediment layers were deposited in ancient streams and lakes.

The latest results indicate that these wetter scenarios were correct for the lower portions of Mount Sharp.

“During the traverse of Gale, we have noticed patterns in the geology where we saw evidence of ancient fast-moving streams with coarser gravel as well as places where streams appear to have emptied out into bodies of standing water,” Vasavada emphasised.

The prediction was that we should start seeing water-deposited, fine-grained rocks closer to Mount Sharp.

“Now that we have arrived, we are seeing finely laminated mud-stones in abundance. These silty layers in the strata are interpreted as ancient lake deposits,” he pointed out.

“These finely laminated mud-stones are very similar to those we see on Earth,” added Woody Fischer, professor of geobiology and coauthor of the paper.

The mud-stones indicates the presence of bodies of standing water in the form of lakes that remained for long periods of time, possibly repeatedly expanding and contracting during hundreds to millions of years.

These lakes deposited the sediment that eventually formed the lower portion of the mountain.

A lingering question surrounds the original source of the water that carried sediment into the crater.

For flowing water to have existed on the surface, Mars must have had a thicker atmosphere and warmer climate.

Curiosity has been exploring Gale Crater since August 2012.

In mid-September 2014, the rover reached the foothills of Mount Sharp. Curiosity has been exploring the base of the mountain since then.

The new findings were published in the journal Science.

(IANS)

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Scientists Take Peek Behind Those Sad Puppy Dog Eyes and Find a Unique Muscle

Pooches use the muscle to raise their eyebrows and make the babylike expression

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Scientists, Sad, Puppy
FILE - Lexy, a therapy dog, is seen at Fort Bragg, N.C., Feb. 18, 2014. A study released June 17, 2019, suggests that over thousands of years of dog domestication, people preferred dogs that could pull off the "puppy dog" eyes look. VOA

What’s behind those hard-to-resist puppy dog eyes?

New research suggests that over thousands of years of dog domestication, people preferred pups that could pull off that appealing, sad look. And that encouraged the development of the facial muscle that creates it.

Today, pooches use the muscle to raise their eyebrows and make the babylike expression. That muscle is virtually absent in their ancestors, the wolves.

“You don’t typically see such muscle differences in species that are that closely related,” said Anne Burrows of Duquesne University in Pittsburgh, an author of the study released Monday by the Proceedings of the National Academy of Sciences.

Scientists, Sad, Puppy
FILE – A female red wolf emerges from her den sheltering newborn pups at the Museum of Life and Science in Durham, N.C., May 13, 2019. VOA

Dogs differ from wolves in many ways, from having shorter snouts, smaller sizes and more expressive faces. And unlike wolves, dogs heavily rely on human eye contact, whether to know when someone’s talking to them or when they can’t solve a problem, like hopping a fence or getting out the door.

Burrows and her colleagues examined the eye muscles in the cadavers of six dogs and two wolves. They found dogs have a meaty eye muscle to lift their eyebrows and make puppy dog eyes. But in wolves, the same muscle was stringy or missing.

The scientists also recorded 27 dogs and nine wolves as each stared at a person. Pet pooches frequently and intensely pulled back their eyebrows to make sad expressions, while the wolves rarely made these faces, and never with great intensity.

The researchers believe dogs, over their relatively short 33,000 years of domestication, used this eye muscle to communicate, possibly goading people to feed or care for them — or at least take them out to play. And people, perhaps unwittingly, obliged.

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‘Profound’ implications

Dog experts not involved with the study were impressed.

“The implications are quite profound,” said Brian Hare from Duke University, who edited the article. Hare wrote in an email that these muscles almost certainly developed because they gave dogs an advantage when interacting with people, and people have been unaware of it.

“The proof has been in their puppy dog eyes all this time!” he said.

Scientists, Sad, Puppy
Over thousands of years of dog domestication, people preferred pups that could pull off that appealing, sad look. Pixabay

Evan MacLean at the University of Arizona called the findings fascinating, but cautioned that the muscle difference could be an indirect effect of other changes rather than a specific response to human influence.

Clive Wynne of the Canine Science Collaboratory at Arizona State University said: “Kudos to the researchers for thinking of a cool way to investigate an important aspect of dogs’ success” with humans.

But he noted in an email that the study has a few snags, particularly the small sampling — only five dog breeds were examined and videos were mainly of Staffordshire bull terriers — and the lack of background information about each animal.

“Did these wolves regularly meet people bearing gifts that might be worth asking for with an endearing face?” he asked.

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Burrows said she planned follow-up studies to examine more breeds. (VOA)