Alchemical symbol for arsenic

Image via Wikipedia

After a 24-hour-long media hype, the official anonuncement came at NASA press conference. No, it’s not about “alien life” evidences recently found. At least, *not yet*. But the results of a recent research are really stunning: Life may exist elsewhere in the universe, under the circumstances we couldn’t even dream of. “Arsenic, in place of phosporus” ? Ground-breaking for sure.

Amplify’d from www.nytimes.com

Scientists said Thursday that they had trained a bacterium to eat and grow on a diet of arsenic, in place of phosphorus — one of six elements considered essential for life — opening up the possibility that organisms could exist elsewhere in the universe or even here on Earth using biochemical powers we have not yet dared to dream about.

The bacterium, scraped from the bottom of Mono Lake in California and grown for months in a lab mixture containing arsenic, gradually swapped out atoms of phosphorus in its little body for atoms of arsenic.

Scientists said the results, if confirmed, would expand the notion of what life could be and where it could be. “There is basic mystery, when you look at life,” said Dimitar Sasselov, an astronomer at the Harvard-Smithsonian Center for Astrophysics and director of an institute on the origins of life there, who was not involved in the work. “Nature only uses a restrictive set of molecules and chemical reactions out of many thousands available. This is our first glimmer that maybe there are other options.”

Felisa Wolfe-Simon, a NASA astrobiology fellow at the United States Geological Survey in Menlo Park, Calif., who led the experiment, said, “This is a microbe that has solved the problem of how to live in a different way.”

Read more at www.nytimes.com

Biologists think, the strange green thing seen on the 3D computer image was one of the earliest living creatures on the earth. The fossil was found in England and is probably more than 400 million years old.

Amplify’d from www.archaeologydaily.com
The leathery Drakozoon kept tentacles hidden in a hood which it would then fling out to trap passing prey
The unique animal lived in the ocean approximately 425 million years ago and has been revealed for the first time today.

A 3D computer mode of a primitive Drakozoon has been created from the only known fossilised specimen of the creature.

The model will help researchers understand what primitive species on early Earth looked like and how they might have evolved into the types of creatures that are around today.

The Drakozoon specimen was found in the Herefordshire Lagerstätte, one of England’s richest deposits of soft-bodied fossils.

Drakozoon lived in the ocean during the Silurian Period, 444 to 416 million years ago, and today’s model hints at how it lived.

The research reveals that Drakozoon was a cone-shaped creature with a hood and it probably had a leathery exterior skin.

It appears to have survived in the ocean by attaching itself to hard surfaces such as rock.

It was approximately 3mm long, and used filament-bearing tentacles to catch and eat organic particles in seawater. It pulled its hood down over its body for protection against predators, pulling it back again to expose its tentacles when danger passed.

Some scientists think the creatures had repeated units, similar to a caterpillar with its many segments and legs, while others think that their bodies were structured in more free-form ways, similar to slugs.

The research was published today in the journal Biology Letters.

In today’s study, the researchers analysed their 3D model and discovered that Drakozoon had eight deep ridges on either side of its body.

They suggest that these deep ridges are the genetic remnants from a time when Drakozoon had a body made of repeated units, supporting the theory that the earliest creatures on Earth were also made of repeated units.

The researchers created their 3D model by physically slicing a fossil into 200 pieces. These pieces were individually photographed and the images were fed into a computer, which generated the 3D model.

The scientists say it is very rare to find ancient soft bodied creatures intact because they normally decompose before they can be preserved in sediment.

The soft bodied Drakozoon was perfectly preserved because it lived in an area that was covered in volcanic ash, following a volcanic eruption that instantly entombed it and other creatures living with it, keeping it intact for 425 million years.

Read more at www.archaeologydaily.com

Since 1998, our view on Mars have been changing very fast: from a “dead planet” with “nothing interesting at all” to an exciting world that hides the mysteries of life in it.This sounds intriguing to me:

If microbes survive deep below Mars, they could be transported to the surface by water gushing up from deep underground.

Keep an eye on Mars; it seems we’ll get a series of “shocking news” very soon.

clipped from news.bbc.co.uk

White tips may be areas of freshly exposed ice

A probable active glacier has been identified for the first time on Mars.

The icy feature has been spotted in images from the European Space Agency’s (Esa) Mars Express spacecraft.
Ancient glaciers, many millions of years old, have been seen before on the Red Planet, but these ones may only be several thousand years old.
The young glacier appears in the Deuteronilus Mensae region between Mars’ rugged southern highlands and the flat northern lowlands.
“If it was an image of Earth, I would say ‘glacier’ right away,” Dr Gerhard Neukum, chief scientist on the spacecraft’s High Resolution Stereo Camera (HRSC) told BBC News.
“We have not yet been able to see the spectral signature of water. But we will fly over it in the coming months and take measurements. On the glacial ridges we can see white tips, which can only be freshly exposed ice.
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