Science & Technology


New Study Finds Apex Chert Formation Fossils Aren't Life

microscopic fossils
The Apex Chert microfossils formed in association with hot fluids near a volcanic structure.
Scientists have been arguing for years about microscopic structures in 3.5-billion-year-old rocks: some think they are the earliest fossilized life yet found, while others see just geology. A new study says the structures are not fossils after all, and cautions that how we interpret such structures will affect our search for life beyond Earth.

Structures thought of as the oldest known fossils of microbes might actually be microscopic mineral formations not associated with life, suggesting that astrobiologists have to be careful calling alien objects "life" when scientists have trouble telling what is or was alive on Earth.

More than 20 years ago, microscopic structures uncovered in the roughly 3.5-billion-year-old Apex Chert formation in western Australia were described as the oldest microbial fossils. These structures were interpreted as cyanobacteria, once known as blue-green algae, embedded in a silica-loaded rock formed in a shallow marine setting. These structures were all detected in slices of rock just 300 microns thick, or roughly three times the diameter of a human hair.
Magic Wand

Genetic mutation as a factor of evolutionary survival and biodiversity: Research shows not only the fittest survive

© Unknown
Darwin's notion that only the fittest survive has been called into question by new research published today (27 March 2011) in Nature.

A collaboration between the Universities of Exeter and Bath in the UK, with a group from San Diego State University in the US, challenges our current understanding of evolution by showing that biodiversity may evolve where previously thought impossible.

The work represents a new approach to studying evolution that may eventually lead to a better understanding of the diversity of bacteria that cause human diseases.

Conventional wisdom has it that for any given niche there should be a best species, the fittest, that will eventually dominate to exclude all others.

This is the principle of survival of the fittest. Ecologists often call this idea the 'competitive exclusion principle' and it predicts that complex environments are needed to support complex, diverse populations.

Professor Robert Beardmore, from the University of Exeter, said: "Microbiologists have tested this principle by constructing very simple environments in the lab to see what happens after hundreds of generations of bacterial evolution, about 3,000 years in human terms. It had been believed that the genome of only the fittest bacteria would be left, but that wasn't their finding. The experiments generated lots of unexpected genetic diversity."

The coolest star in the sky! Newly discovered 'Brown Dwarf' has same temperature as a cup of tea

Brown dwarf sun

At last: The coldest ever brown dwarf, right, was found hiding beside a brighter star 75m light years away
Scientists were this week amazed after the discovery of space's dimmest and coldest star - with a temperature the same as a cup of tea.

The two brown dwarf stars stunned astronomers when they were spotted through a set of three high-powered telescopes.

Both of them are about the same size as Jupiter but the smaller, more distant, star has a surface temperature of around 100 degrees.

The incredibly cool temperature - the same as a freshly boiled cup of tea - makes it the coldest one in the night sky.

A warmer and brighter companion had originally obscured the brown dwarf which has been named CFBDSIR J1458+1013B.

But with new, more powerful telescopes, astronomers were able to see the star, which is almost five times dimmer and 130 degrees cooler than the previous record.

The brown dwarf may represent a new class of cosmic objects straddling the division between stars and planets.

'We were very excited to see that this object had such a low temperature, but we couldn't have guessed that it would turn out to be a double system and have an even more interesting, even colder component,' said star-gazer Philippe Delorme of the Institut de planétologie et d'astrophysique de Grenoble which studied the brown dwarf.

2,500-Year-Old Preserved Human Brain Discovered

oldest brain
© York Archaeological Trust
Heslington brain
A piece of the preserved Heslington brain after it was removed from the skull in which it was found.
A 2,500-year-old human skull uncovered in England was less of a surprise than what was in it: the brain. The discovery of the yellowish, crinkly, shrunken brain prompted questions about how such a fragile organ could have survived so long and how frequently this strange type of preservation occurs.

Except for the brain, all of the skull's soft tissue was gone when the skull was pulled from a muddy Iron Age pit where the University of York was planning to expand its Heslington East campus.

"It was just amazing to think that a brain of someone who had died so many thousands of years ago could persist just in wet ground," said Sonia O'Connor, a postdoctoral research fellow at the University of Bradford. O'Connor led a team of researchers who assessed the state of the brain after it was found in 2008 and looked into likely modes of preservation.

"It's particularly surprising, because if you talk to pathologists who deal with fresh dead bodies they say the first organ to really deteriorate and to basically go to liquid is the brain because of its high fat content," O'Connor said.

When it was found, the skull - which belonged to a man probably between 26 and 45 years old - was accompanied by a jaw and two neck vertebrae, bearing evidence of hanging and then decapitation. Cut marks on the inside of the neck indicate that the head was severed while there was still flesh on the bones, O'Connor said. There is, however, no indication of why he was hanged, and the rest of his remains have yet to be found.

More than a decade earlier, O'Connor was involved in the discovery of 25 preserved brains within medieval-era remains from Kingston-upon-Hull in England. Aside from the brains, only bones remained, and all other soft tissue was gone.

Nuclear Waste and "Spent Nuclear Fuel" : The Largest Concentration of Radioactivity on the Planet is in the USA

Spent fuel pool
© n/a
Spent fuel pool at the top of a nuclear reactor
US stores spent nuclear fuel rods at 4 times pool capacity

In a recent interview with The Real News Network, Robert Alvarez, a nuclear policy specialist since 1975, reports that spent nuclear fuel in the United States comprises the largest concentration of radioactivity on the planet: 71,000 metric tons. Worse, since the Yucca Mountain waste repository has been scrapped due to its proximity to active faults (see last image), the US Nuclear Regulatory Commission has allowed reactor operators to store four times more waste in the spent fuel pools than they're designed to handle.

Each Fukushima spent fuel pool holds about 100 metric tons, he says, while each US pool holds from 500-700 metric tons. A single pool fire would release catastrophic amounts of radioactivity, rendering 17-22,000 square miles of area uninhabitable. That's about the size of New Hampshire and Vermont - from one pool fire.

UK: 100 Bombs are Washed up by the Supermoon: Lunar Phenomenon Blamed as World War II Devices are Detonated

100 bombs are washed up by the Supermoon: Lunar phenomenon blamed as Second World War devices are detonated on Hampshire beach

For decades they lay beneath the sea, undisturbed by time or tide.

But after 70 years, almost 100 Second World War bombs finally fulfilled their explosive destiny yesterday, thanks to the power of the 'Supermoon'.

A Navy bomb disposal team detonated them after abnormal tides thought to be caused by the unusual proximity of the moon washed them up on a Southampton beach.

Prehistoric Protein Components Revealed in Reptile Skin

© N. P. Edwards
50-Million-year-old reptile skin from the Green River Formation, USA. A team of researchers led by the University of Manchester in the UK have used modern infrared technology to show that protein residue has survived within the remarkably preserved skin. The small sample is about 8 cm long.
Scientists from the UK's University of Manchester have imaged skin compounds from a reptile that lived 50 million years ago, according to a paper published online March 23 in Proceedings of the Royal Society B: Biological Sciences.

Known as amides, these chemicals of the ancient life are now visible to the human eye using infrared and x-ray technology to unveil the structure of fossilized soft tissues.

The technique is called non-destructive Fourier Transform InfraRed (FTIR), and results were corroborated using other quantitative methods as well as comparison with the skin of living reptiles.

"Here physics, palaeontology and chemistry have collided to yield incredible insight to the building blocks of fossilized soft tissue," said study coauthor Dr. Phil Manning of the University of Manchester in a press release from the university. "It was a privilege to work with some of the world's top scientists from multiple disciplines, all to help unlock secrets locked in the sands of time."

"The results of this study have wider implications, such as understanding what happens to buried wastes over long periods of time. The fossil record provides us with a long-running experiment, from which we can learn in order to help resolve current problems," Manning said.

Milky Way's 'twin' discovered as astronomers find a supermassive black hole

Lookalike: The centre of spiral galaxy, NGC 253, hosts a twin of Sagittarius A*, the bright radio source at the heart of our own Milky Way
It's enough to make TV's favourite physicist, Brian Cox, excited.

Astronomers have found that the centre of the galaxy nearest to our own hosts a twin of Sagittarius A*, the bright radio source that lies at the core of our Milky Way and which harbors a massive black hole.

Scientists studied the spectacular spiral galaxy, NGC 253, with Chile's Very Large Telescope (VLT) and NASA's Hubble Space Telescope when they made the find.

Andrea Ghez, professor of physics and astronomy at UCLA, who studied the stars and planets, told the Daily Galaxy website that through combining these observations they learnt the black hole was born billions of years ago, perhaps as very massive stars collapsed at the end of their life cycles and joined together to create a single, supermassive object.

Is Homosexuality Based on a Brain Chemical?

Brain Regions
© Dreamstime
The brain chemical serotonin could be responsible for male-male attraction.

A male mouse's desire to mate with either a male or a female is determined by the brain chemical serotonin, scientists report in a new study. The finding demonstrates for the first time that a neurotransmitter governs sexual preference in mammals.

Serotonin is known to regulate sexual behaviors, such as erection, ejaculation and orgasm, in both mice and men. The compound generally dampens sexual activity; for instance, antidepressants that increase the amount of serotonin in the brain sometimes decrease sex drive.

Neuroscientist Yi Rao of Peking University and the National Institute of Biological Sciences in Beijing, and his collaborators have now shown that serotonin also underlies a male's decision to woo a female or another male. They published their results in the March 24 issue of the journal Nature.

Rao and his team genetically engineered male mice to lack either serotonin-producing neurons or a protein that is crucial for making serotonin in the brain. Both types of altered mouse couldn't make serotonin.

Looking Up: Waiting for the Next Supernova

© European Southern Observatory
This photo shows the newly discovered Supernova 1992C in the barred spiral galaxy NGC 3367. The supernova is the bright, star-like object in the lower left area (southeast of the centre of the galaxy), at the tip of a spiral arm. The 16.5-magnitude supernova was discovered by ESO astronomer Hans van Winckel on January 28, 1992.

One of these days we might see a supernova. It might seem more correct to say "one of these nights," but a star exploding in our galaxy as a supernova would easily be so bright it would be seen in a blue daytime sky, outshining any star or planet in the night sky.

We are long overdue. Supernovae are very rare, although astronomers say they should occur on the average every few hundred years. The last one seen in the Milky Way Galaxy was in 1680.

A supernova can become so bright - for a brief time- that the star outshines every star in the galaxy. The one in 1680 was not particularly brilliant as seen from Earth, but some have been- notably the great supernova of 1572 in Cassiopeia and another in the year 1054 in Taurus.

Several notable supernovae have been recorded through history, but none in our own galaxy since the early days of the telescope! Much of what we know today about these cosmic catastrophes come from observations of other galaxies.

Distant galaxies generally are so far away we cannot discern individual stars, although large professional observatories have photographed faint stars in nearer galaxies such as the great Andromeda Galaxy, visible to the unaided eye as a hazy patch.

While we wait for the next supernova in our home galaxy to dazzle our eyes, for both professional and amateur backyard-variety astronomers, it is a wonder to see a star within the faint smudge of a far away galaxy, where no star had been seen before.