Official "Science News" Thread

[cheesehead]

A blog entry, rather than "news":

http://blogs.scientificamerican.com/...-from-a-stone/

[kladner]

I think Andrew Zimmern of Bizarre Foods has covered things like that. It's an interesting story, too.

[ewmayer]

Bizarre 500-Million-Year-Old Creature Unearthed: During the Cambrian explosion, the diversity of life exploded and bizarre sea creatures such as the Helcocystis moroccoensis flourished.

A new fossilized, cigar-shaped creature that lived about 520 million years ago has been unearthed in Morocco.

The newfound species, Helicocystis moroccoensis, has "characteristics that place it as the most primitive echinoderm that has fivefold symmetry," said study co-author Andrew Smith, a paleontologist at the Natural History Museum in London, referring to the group of animals that includes starfish and sea urchins. Modern echinoderms typically have five-point symmetry, such as the five arms of the starfish or the sand dollar's distinctive pattern.

The primitive sea creature, described Tuesday in the journal Proceedings of the Royal Society B, could even change its body shape from slender to stumpy. Researchers say it is a transitional animal that could help explain how early echinoderms evolved their unique body plans, Smith said.

Cambrian explosion expert Dr. Sigmund Schaden-Freud of the University of Vienna commented, "Sometimes a cigar is just an echinoderm."


Astronomers spy on galaxies in the raw: A CSIRO radio telescope has detected the raw material for making the first stars in galaxies that formed when the Universe was just three billion years old.

[only_human]

Genetic sequencing from a >500,000 year old horse bone.
First horses arose 4 million years ago (nature.com)

“We have beaten the time barrier,” says evolutionary biologist Ludovic Orlando of the University of Copenhagen, who led the work with colleague Eske Willerslev. Noting that the oldest DNA sequenced before this came from a polar bear between 110,000 and 130,000 years old, Orlando says: “All of a sudden, you have access to many more extinct species than you could have ever dreamed of sequencing before.”

The team was able to sequence such old DNA partly because of the freezing ground temperatures in the area where the bone was found, which would have slowed the rate of DNA decay.

But the researchers were also successful because they had perfected techniques for extracting and preparing the DNA to preserve its quality for sequencing. They targeted tissue within the fossil which has high DNA content, such as collagen. They also combined DNA sequencing techniques to get maximum DNA coverage — using routine next-generation sequencing with single-molecule sequencing in which a machine directly reads the DNA without the need to amplify it up which can lose some DNA sequences.

Ancient horse is oldest creature to reveal DNA sequence (latimes.com)

Orlando and an international team of collaborators pieced together even the tiniest of DNA fragments recovered from the bone. Such genetic puzzle assembly generally includes multiple samples from each part of the genome, sometimes as many as five or 10. In this case, the so-called coverage was just 1.12.

That's not enough detail to say much about what the horse looked like, said Eske Willerslev, an evolutionary biologist at the Natural History Museum of Denmark who worked on the study. Team members suggested the horse was about the size of a modern Icelandic or Arabian horse, though it probably was less muscular, and perhaps slower.

"If they were fast runners, it was not because of the same genes we know of today," Orlando said.

As part of the genetic sleuthing, the team also sequenced the DNA of a 43,000-year-old horse fossil, five modern domesticated horses, a wild Przewalski's horse native to the Mongolian steppes, and a donkey from the Copenhagen Zoo named Willy.

By comparing all of these genomes, the researchers determined that the most recent common ancestor of all these species — as well as zebras — lived 4 million to 4.5 million years ago. That's about 2 million years earlier than previously thought, and allows for far more time for horses to have evolved into the animals we know today.

World's Oldest Genome Sequenced From 700,000-Year-Old Horse DNA (nationalgeographic.com)

Studies on the half-life of DNA suggest that even under ideal circumstances, DNA sequences older than 1.5 million years will be too short to be readable.

As is the case with the majority of ancient fossils, most of the DNA they found was from bacteria that had populated the bone after the horse died. Using DNA from modern horses as a reference, the team was able to identify "endogenous" DNA that belonged to the ancient horse itself.

"We sequenced 12 billion DNA molecules, of which 40 million [were of] horse origin," said Orlando. "There was a bit of horse DNA in an ocean of microbial DNA."

[Xyzzy]

http://arstechnica.com/science/2013/...-rat-revealed/

[science_man_88]

NASA probe finds new zone at doorstep to interstellar space

CAPE CANAVERAL, Florida (Reuters) - Reports last summer than NASA's long-lived Voyager 1 space probe had finally left the solar system turned out to be a bit premature, scientists said on Thursday.

[kladner]

Originally Posted by science_man_88

NASA probe finds new zone at doorstep to interstellar space

Your link is missing the "h" in "http".

[science_man_88]

Massive Earthquakes Make Volcanoes Sink

The biggest earthquakes also move mountains.
The massive earthquakes that struck Japan and Chile in 2011 and 2010, respectively, sank several big volcanoes by up to 6 inches (15 centimeters), two new

[Xyzzy]

http://arstechnica.com/science/2013/...ves-in-norway/

[kladner]

Originally Posted by Xyzzy

http://arstechnica.com/science/2013/...ves-in-norway/

Excellent article! Fascinating stuff.

[Uncwilly]

Awesome video of Martian moon Phobos passing overhead, shot by NASA's Curiosity probe: