Secret History
Geneticists studying DNA now say that, to the contrary, a previously unknown archaic species of human, a cousin of the Neanderthals, may have lingered in Africa until perhaps 25,000 years ago, coexisting with the modern humans and on occasion interbreeding with them.
The geneticists reached this conclusion, reported on Thursday in the journal Cell, after decoding the entire genome of three isolated hunter-gatherer peoples in Africa, hoping to cast light on the origins of modern human evolution. But the finding is regarded skeptically by some paleoanthropologists because of the absence in the fossil record of anything that would support the geneticists' statistical calculations.
Two of the hunter-gatherers in the study, the Hadza and Sandawe of Tanzania, speak click languages and carry ancient DNA lineages that trace to the earliest branchings of the human family tree. The third group is that of the forest-dwelling pygmies of Cameroon, who also have ancient lineages and unusual blood types.
The geneticists, led by Joseph Lachance and Sarah A. Tishkoff of the University of Pennsylvania, decoded the entire genomes of five men from each of these groups. The costs of whole-genome sequencing have fallen so much that the technique can now be applied to populations for the first time, said Dr. Tishkoff, who paid the company Complete Genomics around $10,000 for each of the 15 genomes.
1. The Maya
The Maya are perhaps the classic example of a civilization that was completely lost, its great monuments, cities and roads swallowed up by the central American jungles, and its peoples scattered to small villages. Though the languages and traditions of the Maya still survive up to the present day, the civilization's peak was during the first millennium AD, when their greatest architectural feats and massive agricultural projects covered a vast region in the Yucatán - today, an area stretching from Mexico to Guatemala and Belize. One of the largest Mesoamerican civilizations, the Maya made extensive use of writing, math, an elaborate calendar, and sophisticated engineering to build their pyramids and terraced farms. Though it's often said that the Maya civilization began a mysterious decline in roughly the year 900, a great deal of evidence points to climate change in the Yucatán combined with internecine warfare, which resulted in famine and abandonment of the city centers.
About 40,000 years ago, a huge volcanic eruption west of what is now Naples, Italy, showered ash over much of central and Eastern Europe. Some researchers have suggested that this super-eruption, combined with a sharp cold spell that hit the Northern Hemisphere at the same time, created a "volcanic winter" that did in the Neandertals. But a new study of microscopic particles of volcanic glass left behind by the explosion concludes that the eruption happened after the Neandertals were already mostly gone, putting the blame for their extinction on competition with modern humans.
Why the Neandertals disappeared is one of archaeology's longest-running debates. Over the years, opinions have shifted back and forth between climate change, competition with modern humans, and combinations of the two. Earlier this year, the climate change contingent got a boost when a European team determined that the Italian eruption, known as the Campanian Ignimbrite (CI), was two to three times larger than previous estimates. The researchers calculated that ash and chemical aerosols released into the atmosphere by the eruption cooled the Northern Hemisphere by as much as 2°C for up to 3 years.

A life-size granite lion sculpture discovered in the town of Karakiz in Turkey. Dating back more than 3,200 years, to the time of the Hittite Empire, the lion is shown "prowling forward" with rippling muscles and a curved tail. In antiquity there would have been a second lion connected to it, bringing the total weight of the sculpture to about 5 tons (10,000 pounds).
One idea is that the statues, created between 1400 and 1200 B.C., were meant to be part of a monument for a sacred water spring, the researchers said.
The lifelike lions were created by the Hittites who controlled a vast empire in the region at a time when the Asiatic lion roamed the foothills of Turkey.
"The lions are prowling forward, their heads slightly lowered; the tops of their heads are barely higher than the napes," write Geoffrey Summers, of the Middle East Technical University, and researcher Erol Özen in an article published in the most recent edition of the American Journal of Archaeology.
The two lion sculptures have stylistic differences and were made by different sculptors. The lion sculpture found in the village of Karakiz is particularly lifelike, with rippling muscles and a tail that curves around the back of the granite boulder.
"The sculptors certainly knew what lions looked like," Summers told LiveScience in an interview. He said that both archaeological and ancient written records indicate that the Asiatic lion, now extinct in Turkey, was still very much around, some even being kept by the Hittites in pits.
Curiously the sculpture at Karakiz has an orange color caused by the oxidization of minerals in the stone. Summers said that he doesn't believe it had this color when it was first carved.

A rare accounting document, half-concealed beneath a coat of arms design, has revealed the activities of Italian bankers working in early 15th century London, decades before the capital became a financial powerhouse.
Among the pages of a bound collection of traditional English crests held at the London College of Arms -- the headquarters of British heraldry -- are several papers belonging to a book of debtors and creditors for Florentine merchant-banking company, Domenicio Villani & Partners.
The coats of arms are estimated to have been painted in 1480, during a time when good quality paper was scarce and anything that was available was re-used.
The banking records, only half-covered by the design, date from 1422-24 and hint at the extensive trade in wool and other commodities produced in Britain during the era.

Snefru's Red Pyramid at Dahshur. This was Egypt's first true pyramid. Credit:
The first king of the 4th dynasty, Snefru (reigned 2575-2551 BC) built Egypt's first true pyramid at Dashur, after a couple of failures. The task was overshadowed by his son Khufu, or Cheops, when he built the Great Pyramid at Giza.
More than 3.5 million cubic meters (123 million cubic feet) of building material were mined and transported at Dashur, some 20 miles from Cairo, yet very little evidence remains of what went on at the pyramid practice site some 4500 years ago. Nature wiped virtually any trace of human activity.
To expose the ancient pyramid playground, a team of Earth scientists from Germany turned to fractals.
Fractals are natural or artificially created geometric patterns that form designs. These appear to repeat themselves over and over when magnified.
Deltas created where rivers meet the ocean often display fractal properties. Dissected by river channels which drain into the floodplain of the Nile, the area around Dahshur was indeed supposed to show an abundance of natural fractals. The new study showed that was't really the case.
This earthlodge observatory is located at the Ocmulgee Mounds National Monument in Macon, Georgia, a site which dates to around 900 AD. The Ocmulgee Mounds site contains an enormous earthen pyramid ninety feet tall known as the Great Temple Mound. (The Mayan pyramid at Chichen Itza is only 75 feet tall by comparison.) This pyramid was stuccoed in bright orange Georgia clay and magnetometer scans showed that it had a spiral ramp leading to its summit angled to the Ocmulgee River below. A smaller earthen pyramid known as the Lesser Temple Mound forms a right angle with the Great Temple Mound and the two pyramids form the boundaries of a giant central plaza.
Sorry, Amelia, no birthday present this year. But it's not been for a lack of trying.
Throughout the years there have been a number of search attempts to find Earhart or wreckage of her plane. Now 75 years after she vanished in her Lockheed Model 10 Electra over the Pacific Ocean, the most recent hope of finding evidence of Earhart's plane is fading.
Discovery News reported last week that a $2.2 million expedition by The International Group for Historic Aircraft Recovery (TIGHAR) came to an end due to the challenges of exploring a steep, underwater coral cliff.
You remember, a couple of months ago, Secretary of State Hillary Clinton held a press conference, and gave an boost to the credibility to the TIGHAR hunt for Earhart's plane.
TIGHAR researchers believed that when Earhart and her navigator Fred Noonan went missing July 2, 1937, they made an emergency landing on a reef near the uninhabited island Nikumaroro.

A statue of Genghis Khan, the founder of the Mongol Empire, in Ulaanbatar, Mongolia.
Historians have long speculated that periods of drought pushed the Mongol hordes to conquer their neighbors, but preliminary new findings suggest that theory may be exactly backward. Instead, consistent rain and warm temperatures may have given the Mongols the energy source they needed to conquer Eurasia: grass for their horses.
This idea, bolstered by the discovery of tree rings that preserve a climate history of Mongolia back to 657 A.D., is still in the preliminary stages of investigation.
LiveScience spoke with Amy Hessl, the dendochronologist, or tree-ring researcher, who along with collaborators Neil Pederson and Baatarbileg Nachin first discovered the preserved trees hinting at the weather during the era of the Mongols.

The silver recovered from the S.S. Gairsoppa, as seen by scanners of the Odyssey expedition.
The haul was retrieved from the S.S. Gairsoppa, a 412-foot steel-hulled British cargo ship that sank in February 1941.
The expedition, by Odyssey Marine Exploration, a company specializing in shipwreck exploration, recovered 1,203 bars of silver, totaling 1.4 million ounces. Viewers will have the chance to follow the pursuit of the lost treasure on an upcoming Discovery Channel special produced by JWM Productions.
The cache has been transported to a secure facility in the United Kingdom, which contracted the project under the Department of Transport. Under the contract, Odyssey will retain 80 percent of the net value of recovered goods, after expenses, according to a press release.
Comment: Very interesting... it makes us wonder whether other so-called "tombs" were in fact meant for counting down the days the until the return of the "sky gods"...
Newgrange, Ireland: older than the Great Pyramid