Monday, April 19, 2010

Science Watch (April 2010)

Here are this week's top scientific stories...

Hammerhead leap into the tons category.
Australian fishermen were excited when they captured a giant Smooth Hammerhead Shark in the east coast of the Australia Sea. The shark weighs 1.25 tons, has a length of approximately 6 meters. It is thought to be 40 years old at least. The Smooth Hammerhead Shark is an endangered species. They are famous for never attacking human beings.

There's life where you think nothing is.
Although these microscopic creatures may look beautiful in photographs, but many of them are not even visible to the human eye. Most are microbes of bacteria, though there are also worms burrowing into the sea bed and ocean insects less than 1mm long.
The only way scientists have been able to make the discoveries is using new technology like DNA sequencing that tells the different species apart and remotely operated submarines that can operate thousands of feet under the sea.
The survey was carried out by scientists around the world as part of a 10-year international project to find out more about the oceans, the Census of Marine Life.
One project took ocean samples from more than 1,200 sites around the world in order to find out more about microbial life. It found microbes with 18 million different DNA sequences, suggesting there could be millions of species although only a few thousand have been described.
Another study found 7,000 new genus of bacteria in the Western English Channel alone. A sponge from Australia's Great Barrier Reef was home to almost 3,000 different types of bacteria.
Previously it was thought there was around 100,000 microbial cells in every litre of seawater but scientists now think there could be one billion.
A separate study of holozooplankton, that look like tiny transparent insects, doubled the number of known species from 7,000 to 14,000.
A study into roundworms found 500,0000 in a single square metre of ocean floor, while there are now 16,000 known species of seaworms.
John Baross of the University of Washington, who is a contributor to the census, said microscopic life in the oceans sustains 90 per cent of life.
He said the new findings was opening up a "huge frontier" in science that could help explain changes in the food chain, weather patterns and carbon cycles. It will also help predict how climate change will affect the oceans.
"Marine animals alone may account for hundreds of millions microbial species. This is a huge frontier for next decade," he said.

There's a new leech king of the jungle.
The new species—dubbed Tyrannobdella rex, or "tyrant leech king"—was discovered in the remote  Pereuvian Amazon, according to a new study.
Puzzling scientists from the start, the up-to-three-inch-long (about seven-centimeter-long) bloodsucker has large teeth, like its dinosaur namesake Tyrannosaur rex.
The T. rex leech uses its teeth to saw into the tissues of mammals' orifices, including eyes, urethras, rectums, and vaginas.
The leech was first recognized from a specimen plucked from the nose of a girl in Peru's central Chanchamayo Province in 2007. After two years of subsequent field research, the team comprising Mark Siddal and colleagues discovered the leech belongs to a globally scattered group of leeches that all suck on mammalian mucus membranes.
Ironically, the ferocious leech may one day help people. Siddall and his team study leeches to develop anticoagulants—treatments that stop patients' blood from clotting.
Medicinal leeches have been used for more than a century for various medical therapies. Finding a new leech helps scientists better understand the molecules that make leech saliva so beneficial.

Deep in the Mediterranean, scientists have discovered the first complex animals known to live without oxygen.
It was previously thought that only viruses and single-celled microbes could survive without oxygen long-term.
But three new species of multicellular animals found during recent research expeditions live comfortably in oxygen-free depths, said team leader Roberto Danovaro of Italy.
"The bodies of multicellular animals have previously been discovered [in oxygen-free zones] but were thought to have sunk there from upper, oxygenated waters," Danovaro said in a statement. "Our results indicate that the animals we recovered were alive. Some, in fact, also contained eggs."
The new animals are microscopic—each measuring less than a millimeter across—and they resemble tiny jellyfish

The creatures seem to thrive in the extremely salty sediments of the Mediterranean seafloor, one of the most extreme environments on Earth.
Most multicellar organisms, including humans, have structures inside their cells called mitochondria, which use oxygen to convert nutrients into energy molecules known as ATP. While these new animals appear to have modified versions of mitochondria called hydrogenosomes, which can produce ATP without oxygen.

Hair Anybody??
Scientists the US are bullish about the discovery of a new hair-loss gene, something that could help the many millions of men with male pattern baldness.
While the gene is specifically linked to a form of hereditary childhood baldness, the researchers from Columbia, Rockefeller and Stanford universities in the US believe that the discovery may in time help those with adult baldness.
The hereditary form, known as hypotrichosis simplex, causes “hair follicle miniaturisation”, says Dr Angela Christiano, professor of dermatology and genetics and development at Columbia. She and colleagues publish their findings this morning in the journal Nature.
The errant gene culprit, APCDD1, was identified by analysing genetic information from several families from Pakistan and Italy affected by hereditary childhood hair loss.
While this occurs in children affected by hypotrichosis simplex, shrinking follicles are also central to male pattern baldness, says Dr Christiano. In both cases the follicles shrink, causing normal thick hair to be replaced by thin fine hair, also known as “peach fuzz”, the authors write.
Dr Christiano points out that while both conditions deliver a similar result, the gene discovery does not fully explain what lies behind male baldness. Yet, the discovery is important for what it might tell us about the onset of thinning hair.
“The identification of this gene underlying hereditary hypotrichosis simplex has afforded us an opportunity to gain insight into the process of hair follicle miniaturisation, which is most commonly observed in male pattern hair loss or androgenetic alopecia,” Dr Christiano says.

Planets can also go in reverse gear! or rather remain in reverse gear!!!

The nine new planets discovered recently by the European astronomers, two of them orbiting backwards around their nearby star, managed to shake an important planetary theory. However, in such solar systems no Earth-like planets are capable to survive.
It was always believe that all planets orbit in the same direction as the rotation of their host star. However, the prevailing theories of how planets are formed may no longer valid after the astronomers’ announced the discovery of nine new transiting exoplanets, two of which having opposite orbits. 
The standard theories of how solar systems are formed indicate “planets coalesce together out of protoplanetary discs of dust and gas that spin around a star’s equator. As these discs rotate in the same direction as the star spins on its axis, planetary orbits ought also to follow this pattern”. 
However, this discovery proves that those theories will not always apply, especially when the solar system contain giant gas planets that orbit very close to their stars. Those gas planets are called “hot Jupiters” which are believed to migrate inwards after forming in the outer parts of solar systems. 
"The new results really challenge the conventional wisdom that planets should always orbit in the same direction as their stars spin”, said Professor Andrew Cameron of the University of St Andrews when his team presented this discovery at the Royal Astronomical Society’s annual meeting in Glasgow, Scotland. 
Unlike the planets in our solar system, two of the newly discovered planets were orbiting backwards around their star. “Our picture of planetary formation and migration may have been colored by the simplicity of our own solar system”, said Professor Andrew. 
Those backwards orbiting planets suggest that giant gas planets could be caught by the "gravitational tug-of-war" between distant objects like nearby stars or planets, which could turn over their orbital alignment, pushing them into an unusual orbit around their transit stars. 
However, “A dramatic side effect of this process is that it would wipe out any other smaller Earth-like planet in these systems”, said Didier Queloz, another leader of the research team, because Jupiter-sized retrograde planets tend to knock out smaller planets.
Links to sources;


Anonymous said...

cool dude btw lucky you have listed the sources or i wud hav reported this content...just kidding dude!!

sigma'91 said...

good boil down of the week hope you don't disconitnue it...

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