The headline items in the de Young Museum's new special exhibit, "Olmec: Colossal Masterworks of Ancient Mexico" are indeed colossal, similar to the iconic - if much more contemporary - Easter Island heads.

The unique show, organized by many and led by the de Young's Kathleen Berrin and Virginia M. Fields of the Los Angeles County Museum of Art, represents the only chance for visitors to see 140 ancient objects outside their homes in 25 Mexican and U.S. museums. In addition to the huge heads, the exhibition also features many small, fascinating works of art.

The Olmec ("people of the rubber country") created a pre-Columbian civilization in south-central Mexico, now the states of Veracruz and Tabasco. Thriving some 3,500 years ago, the Olmec pre-dated other Mesoamerican civilizations, such as the Zapotecs, Teotihuacans, Aztecs and Mayans.

Unlike many other ancient civilizations, the Olmec disappeared without a trace, leaving uncertainty behind them. Their contemporaries were the golden age of Greece and the Zhou dynasty of China, both known in great detail today, unlike the Olmec.

Details of a mystery cylinder floating in the sky over Torquay, star-shaped lights with vapour trails over Torbay and a silver ship hovering over Brixham are revealed for the first time today.

All three UFO incidents are included in the largest-ever release of official files on unexplained phenomena.

But the Herald Express had already solved one of the 'mysteries' seven years ago thanks to a group of local teenagers and a £13 balloon.

Files released today by The National Archives reveal how UFOs were discussed at the highest level worldwide.

Among the files is a sighting reported by an un-named man from Torquay.

He wrote: "On April 28 1967 I, along with 100 others including schoolteachers, witnessed a silver UFO pass over Torquay at approximately 11.30am.

"The UFO traveled towards Brixham, where it remained stationary for approximately one hour.

"The object was observed by Brixham Coastguards, which was reported to the RAF in Plymouth.

"The object, after remaining stationary over the town, proceeded to fly off."

A freelance archaeologist and his wife came face to face with a chunk of unique Roman history as they walked across a Wigton farm.

Karl James Langford, 36, and his wife Lisa, 43, are over the moon with their chance discovery of a sandstone fragment which still bears part of a Roman inscription.

The couple had gone with their two children - a boy aged two and a five-month-old girl - to visit the remnant of the Maglona Roman fort near Wigton last week when Lisa spotted the stone on the ground. It had been exposed by a heavy rain storm.

Still clearly visible on the sandstone fragment - which is about the size of a tea saucer - are the Roman letters M, R and P.

Karl, 36, believes the artefact may once have spelled the name of the settlement, which was abandoned a few decades before the Romans pulled out of Britain in AD 410.

Contractors working in the Christchurch Square area have unearthed two artefacts, exposed by the force of the 6.3 quake a week ago.

Christchurch Mayor Bob Parker presented the two time capsules at a media briefing today - and says he hopes they will serve as a symbol for the city's recovery.

The capsules, a glass one with a hand-written letter on gold parchment inside, and the other yet to be opened but in a metal container, were found beneath a statue of founding citizen John Robert Godley at Cathedral Square.

It was found by one of the crane operators for Daniel Smith Industries (DSI) and his boss said his first thought was to contact Parker.

Guided by computer simulations that reconstruct a lost world now lying at the bottom of Lake Huron, a team of scientists is preparing to search this spring for ancient artifacts along an underwater ridge that straddles the U.S.-Canada border - a place the researchers believe was a caribou-hunting hot spot about 10,000 years ago for some of the earliest inhabitants of North America.

The planned probe of the Alpena-Amberley Ridge - named for the Michigan and Ontario towns that respectively mark the western and eastern ends of the 160-kilometre-long lake bottom feature - is expected to involve remotely operated sonar devices for mapping the underwater terrain, as well as a team of scuba divers to comb the long-submerged landscape in search of spearheads and other signs of hunting activity from the end of the last ice age.

University of Michigan researchers first announced in 2009 that they'd discovered rock formations along the drowned ridge that appeared eerily similar to well-documented caribou-hunting structures used in prehistoric times by the "Paleo-Indian" peoples who once occupied Canada's Arctic and sub-Arctic territories.

Now under about 35 metres of water, the Lake Huron ridge was once a 16-km-wide upland corridor in a lake-dotted landscape that linked caribou wintering grounds in the south to their summer ranges in present-day Northern Ontario and beyond.

"Scientifically, it's important, because the entire ancient landscape has been preserved and has not been modified by farming, or modern development," project leader John O'Shea, a University of Michigan archeologist, said when the rock structures were discovered. "That has implications for ecology, archeology and environmental modelling.''

The remains of 27 ancient men, women, and children have been found in cliffside caves in Nepal. Many of the bones bear cut marks that point to a previously unknown Himalayan death ritual, experts say.

The corpses - many of which had been stripped of flesh - were placed in the high mortuaries some 1,500 years ago, the team announced Friday.

Nearly 67 percent of the bodies' had been defleshed, most likely with a metal knife, say the researchers, who found the remains in 2010.

After the de-fleshing process, the corpses had been neatly laid to rest on wide wooden shelves, the researchers speculate. But due to centuries of exposure to the elements, the bones and bunks - and much of the caves themselves - had collapsed by the time the team entered the chambers.

Also in the jumble: goat, cow, and horse remains - perhaps sacrificial offerings for the dead, though their purpose remains a mystery.

Dug into characteristically reddish cliffs of the Upper Mustang district, the human-made caves lie at 13,800 feet (4,200 meters) above sea level, high above the village of Samdzong.

In ancient times, rock outcrops and probably ladders would have eased access to the caves. Since then, however, erosion has rendered the chambers accessible to only expert climbers, such as seven-time Everest summiter Pete Athans, who co-led the team.

DNA - deoxyribonucleic acid - is the basis of life. Its molecular structure was discovered in 1953, revealing how it carries all the genetic information needed for organisms to live and reproduce.

Scientists describe it in sequences of letters, and humans inherit three billion from each of their parents. As generations move from place to place, distinctive DNA markers are carried by each and every one of us. In a programme of pioneering research at Edinburgh University, Dr Jim Wilson has been gathering samples of DNA from Scots across the country and this week, in a new book by Alistair Moffat, and in a series of features in The Scotsman, we discover what his innovative work has revealed - and where the Scots came from. Day 1 looks at our origins.

It could force historians to reconsider the origins of the mighty Inca empire.

Archaeologists have discovered and excavated nine tombs in Peru from the pre-Hispanic Wari civilisation, the Peruvian government said yesterday.

The finding in the southern Cusco region suggests the Wari, who flourished in the Peruvian Andes between 700 and 1200 AD, may have controlled areas where the Inca empire later flourished.

Juan Ossio, Peru's minister of culture, said: 'The Incas could have been inspired by the Wari culture, enabling them to develop their entire political system.'

The Incas built the largest empire in the New World between 1400 and 1532 AD.

Burial remains of a dog that lived over 7,000 years ago in Siberia suggest the male Husky-like animal probably lived and died similar to how humans did at that time and place, eating the same food, sustaining work injuries, and getting a human-like burial.

"Based on how northern indigenous people understand animals in historic times, I think the people burying this particular dog saw it as a thinking, social being, perhaps on par with humans in many ways," said Robert Losey, lead author of a study about the dog burial, which has been accepted for publication in the Journal of Anthropological Archaeology.

Syria (Daraa) - The discovery of a Neolithic settlement at al-Maysara archaeological site in 2003, 4 km south east of Daraa governorate, represented a turning point in the history of archaeological discoveries in the governorate.

A preliminary archaeological survey of Yasser Abu Noktah revealed caves, stone grinders and stone mortars and pestles in the area.

In a statement to SANA, Director of Daraa Museum Ayham al-Zoubi said a number of archaeological surveys over the last few years indicated to the presence of prehistoric societies at al-Maysara archaeological site.

He added that the studies of archaeological findings uncovered at the site showed that they belong to the Neolithic Period (8000-5500 B.C.).

Excavation works in 2004 unearthed a number of stone scrapers, awls, spears, arrowheads and axes of different sizes generally used for daily life activities, farming and hunting, he said.