Friday 3 February 2012

Freshen Up With Archaeology Friday (Post V)



Civil War Submarine Finally Revealed:

The Confederate submarine (Photo by Reuters)
For the first time since the U.S. Civil War, the Confederate vessel H.L. Hunley—the world's first submarine to sink an enemy ship—was revealed on January 12 (pictured) after 11 years of conservation work. 

Shown in a South Carolina conservation facility, the Hunley sank the U.S.S. Housatonic off Charleston in 1864. Within minutes the sub itself sank too-killing its eight-man crew and creating an enduring mystery.

Five years after the Hunley wreck's discovery in 1995, conservators raised the sub using a special steel truss that was removed only weeks ago.

"No one alive has ever seen the Hunley complete," said engineer John King on January 12 as a crane lifted the truss at Clemson University's Warren Lasch Conservation Center in North Charleston, Reuters reported on January 13. 
"We're going to see it today."
Explaining Mayan Deforestation and Drought:

A rather interesting article by NASA that deserves a mention here.

Sometime during the ninth century A.D., an apparently prosperous Mayan society collapsed within decades. Why? Could the collapse of the Mayan civilization be a warning to us today?

One possible explanation for the downfall is drought. Central America is naturally prone to drought, but one recent study suggests that Mayan activities may have deepened the dry conditions. In an effort to sustain one of the highest population densities in history, the Mayans transformed the land. They removed nearly all of the forest and replaced it with agricultural crops.

The top map shows how little native forest (dark green) remained at the end of the Mayan period around 950 AD. By cutting down the forest, the Mayans changed their local climate. When NASA scientist Ben Cook examined land use for the era in the Goddard Institute for Space Studies general circulation model, he found that the climate was warmer and drier during the rainy season (June, July, and August) than it would have been had natural forest remained in place.
Map courtesy of NASA.
 Though deforestation didn’t cause a drought, it amplified natural droughts when they occurred. The center and lower images illustrate the change. Places that are drier (brown) and warmer (red) than normal correspond to areas where the forest had been cleared.

How could cutting a forest have such a big impact? Plants interact with the atmosphere. Dark plants—such as dense tropical forest—absorb a lot of energy from the Sun. Lighter colored plants (crops) reflect some energy. When a forest is replaced by lighter colored plants, the land reflects more sunlight, which cools the atmosphere. Cool air sinks, while water vapor needs to rise and condense to create a rainstorm. Without warm, unstable air rising into the atmosphere, rainstorms became less common. The drying pattern is shown in the center image.

The lack of rain helped raise temperatures on land. When energy from the Sun reaches the ground, it either heats the ground or it causes water to evaporate from the soil or transpire from plants. With forests producing less moisture and croplands holding less water, droughts deepened as more and more of the Sun’s energy heated the ground, (lower image).

How permanent was the change? Cook compared climate conditions during the late Mayan era with conditions during the early colonial era (1500-1650), when land use was at a minimum and forests had re-grown over Central America. The warming and drying trend disappeared.

Today, much of the colonial-era forest is gone, but large swaths remain on the Yucatan Peninsula. This forest may help moderate drought. But if it were cut down, Central America might become warmer and drier again.

Why Were the Dinosaurs so Huge ?

My favourite article of the week and a MUST-READ , this article from Discovery explains a lot.

How did some dinosaurs reach such soaring heights -- up to 100 feet high in some cases? Efficient lungs and respiration, along with egg laying, might have given dinos a growth edge when compared to other animals, suggests new research.

The study also negates a popular theory that animals tended to become bigger over the course of their evolution.

While some dinosaurs grew ever larger over subsequent generations, not all did.

"We look at the early history of archosaurs, including some early dinosaurs," said Roger Benson who co-authored the study published in the Proceedings of the Royal Society B.

"We can see that some lineages obtained gigantic body sizes, but others remained small and a few showed evolutionary size reductions."

"Although mammal-like reptiles are small, and dinosaurs in general are big, by the end of our study period, this did not occur to be directed by evolutionary trends. Instead, large-bodied mammal-like reptiles became preferentially extinct, and archosaurs radiated to fill a wide range of body sizes, including giant."
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Benson, a vertebrate paleontologist at the University of Cambridge, explained that "pterosaurs, the flying reptiles, are a good example of a lineage that remained small during our study interval. There were also many small herbivores, like the dinosaur Heterodontosaurus, and small predators like the dinosaur Coelophysis.
Why were dinosaurs so huge ??
 Scan Unwraps Mummy's secrets:


News from Scotland, courtesy of the Scotsman:
 
An Edinburgh University team of radiologists and forensic pathologists have identified the remains as those of a 2,000-year-old Egyptian woman, aged 25-29, with a plate of metal, probably solid gold, in the shape of a flying scarab, placed on her skull.

Another metal disc has also been found on her stomach, and she is clutching a rolled scroll in her right hand against her thigh. The scroll is likely to be a funerary text, combining directions for mummification with guidance for the afterlife, and it could give the mummy’s lineage or name.

Why she died remains a mystery despite the sophisticated scanning techniques normally used to diagnose disease in live patients. The experts believe she is likely to have expired following a common infection, such as then untreatable pneumonia, rather than TB, or syphilis, which would typically have showed up in the bone structure.
The scan (image from The Scotsman)

There is no sign either of injury from broken bones, though the scan does reveal the holes cut in the small bones at the back of her nose by Egyptian embalmers to remove her brain.

Even her teeth appear to be in remarkably good condition, although there are some signs of disease, suggesting she may have suffered from toothache.

Jim Tate, head of conservation and analytical research at the National Museum of Scotland (NMS), said: “Apart from being dead, she was in good health.”

The mummy was brought back to Scotland in 1857 by Alexander Rhind, a 24-year-old Scottish Egyptologist, who discovered it in a tomb in the ancient city of Thebes, now known as Luxor. Meticulous about cataloguing only what he saw, he was critical of so-called “archaeologists” whom he claimed indulged in little more than looting by unwrapping mummies as it destroyed the carefully preserved corpses.

His find was shipped back to Scotland undisturbed and has been in the museum’s collections ever since.
Relatively late in historical terms – from about 10BC – the mummy was “a handsome specimen of the style of ornamenting externally, by means of inlaid or impressed emblems of gold and coloured vitreous composition”, Rhind wrote. But he left the contents untouched.

Ancient Mummy had Prostate Cancer!

Sticking to the Mummy theme, here is some news from Egypt.


A professor from American University in Cairo says discovery of prostate cancer in a 2,200-year-old mummy indicates the disease was caused by genetics, not environment.


The genetics-environment question is key to understanding cancer.

AUC professor Salima Ikram, a member of the team that studied the mummy in Portugal for two years, said Sunday the mummy was of a man who died in his forties.

She said this was the second oldest known case of prostate cancer.

"Living conditions in ancient times were very different; there were no pollutants or modified foods, which leads us to believe that the disease is not necessarily only linked to industrial factors," she said.

A statement from AUC says the oldest known case came from a 2,700 year-old skeleton of a king in Russia.

Recorded Voice of Otto Von Bismarck Released !

It's a great day for German-o-philes today!


A wax cylinder recording of German statesman Otto von Bismarck has been released, the first time his voice has been heard for more than 100 years.

The recording was made in 1889 by a technician working for the inventor of the phonograph, Thomas Edison.

It has now been restored using digital technology by the Thomas Edison National Historical Park museum.
The Otto Von Bismarck Foundation in Germany has called the discovery "sensational".
The Foundation had believed the recordings to be lost.

The cylinder was among 17 found in 1957 in an unlabelled box at Edison's laboratory in the US state of New Jersey.

Bismarck is barely audible on the recordings but can be heard reciting extracts of poetry, songs, and giving words of advice to his son.

Intriguingly, at one point he also breaks into the first lines of the French national anthem, La Marseillaise.
The cylinders have also yielded songs and rhapsodies by German and Hungarian musicians, including what is thought to be the first ever recording of a work by Polish composer Frederyk Chopin.

Why More Maps Should Be Upside Down

If you've utilised a map at any point in your life, whether it's Google Maps to find out which right turn you just missed on the hig...