New Details of Ancient Roman Town Uncovered

New Details of Ancient Roman Town Uncovered

 
Reconstruction of how the Caistor Roman town may have looked in the 4th century AD, showing the settlement's temple.

 
Reconstruction of how the Caistor Roman town may have looked in the 4th century A.D., showing the street grid and public buildings, including bath houses.

New details of a buried ancient Roman town in England are being revealed for the first time using the latest technology.

The newly uncovered features include street grids, clustered public buildings such as temples and baths, the town’s water supply system and possibly a large theater.

The Roman town of Venta Icenorum at Caistor St. Edmund in Norfolk, England, was initially discovered in 1928 when Royal Air Force craft snapped images of the site. Due to the particularly dry summer that year, details of the Roman town stood out as parched lines in the barley fields.

On March 4, 1929, the pictures donned the front page of The Times of London, causing a public sensation.

Now, with a so-called cesium vapor magnetometer that detects changes in magnetic field lines, scientists can "see" more beneath the open fields. The results are confirming the street plan shown by previous aerial photographs as well as a series of public buildings known from earlier excavations.

"The results of the survey have far exceeded our expectations," said lead researcher Will Bowden of the University of Nottingham in England. "It's not an exaggeration to say that the survey has advanced our knowledge of Caistor to the same extent that the first aerial photograph did 80 years ago."

Town map

The survey showed clear traces of a large semi-circular building next to the town's temples, a typical location for a theater in Roman Britain.

"This is a fantastic discovery, and it goes to show that Caistor Roman town still has a great number of secrets to be disclosed in the years ahead through surveys or excavations," said David Gurney, the principal archaeologist at Norfolk Museums & Archaeology Service.

Caistor lies in the territory of the Iceni, the tribe of the British queen Boudica who famously rebelled against the invading forces of the Roman Empire in the first century A.D.

Caistor's long preservation can be attributed to the fact that the town was ultimately supplanted by medieval Norwich and transformed into green fields rather than demolished for modern city buildings. In contrast, most Roman towns with a similar long occupation history were replaced by, and buried beneath, modern towns of Britain and Europe.

Major settlement?

The new survey challenges earlier interpretations of the ancient town, which reconstruction paintings often depicted as a crowded urban area. While the survey showed buildings clustered along the town's main streets, other areas within the street grid were empty and possibly used for agriculture, the researchers say.

They also suggest that the seeming provincial Roman Caistor may have actually been a major settlement from the Iron Age until the 9th century A.D. It was previously thought that life at Roman Caistor ended in the 5th century A.D. when the Roman occupation ended and the Saxons came into power.

However, the new survey clearly shows a large ditched enclosure that cuts the surface of a Roman street, indicating people must have inhabited the area. This along with an earlier discovery of middle Saxon coins and metalwork near the site and the presence of two early Saxon cemeteries in the vicinity suggest the enclosures are possibly signs of continued life in the town after the Roman period. 

Ancient Toolkit Gives Glimpse of Prehistoric Life

Ancient Toolkit Gives Glimpse of Prehistoric Life

Toolkit Contents
The owner of a 14,000-year-old bag was well equipped for hunting and gathering. The contents, pictured, here, include a sickle for harvesting wild plants, a cluster of flint spearheads, a flint core for making more spearheads, a cluster of gazelle toe bones, and part of a second bone tool.

Before the end of the last ice age, a hunter-gatherer left a bag of tools near the wall of a roundhouse residence, where archaeologists have now found the collection 14,000 years later.

The tool set -- one of the most complete and well preserved of its kind -- provides an intriguing glimpse of the daily life of a prehistoric hunter-gatherer.

The contents, as described to Discovery News by Phillip Edwards, a senior lecturer in the Archaeology Program at Melbourne's La Trobe University, show the owner of the bag was well equipped for obtaining meat and edible plants in the wild.

"There was a sickle for harvesting wild wheat or barley, a cluster of flint spearheads, a flint core for making more spearheads, some smooth stones (maybe slingshots), a large stone (maybe for striking flint pieces off the flint core), a cluster of gazelle toe bones which were used to make beads, and part of a second bone tool," he said.

Edwards outlines the finds, attributed to the Natufian culture from a site called Wadi Hammeh 27 in Jordan, in the latest issue of Antiquity.

He believes the tools were enclosed in a hide or wickerwork bag with a strap that would have been worn over the shoulder. Such bags rarely had compartments, so the owner probably protected valuable items by wrapping them in rolls of bark or leather before placing them at the bottom of the bag.

The sickle, constructed out of two carefully grooved horn pieces, was fitted with color-matched tan and grey bladelets. It would have been a marvel of form and function for its day and is the only tool of its kind ever linked to the Natufian people.

The rest of the items were designed to immobilize and then kill game such as aurochs, red deer, hares, storks, partridges, owls, tortoises and the major source of meat -- gazelles.

"A lone hunter or a group of hunters might wait for gazelles to cross their path while waiting behind a low 'hide' made of twigs and brush," Edwards explained.

"They might have worked on making bone beads to wile away the time. Then a hunter could get off a shot while the animals were off their guard. A first shot might wound, but not kill, and then a hunter or a group of them will track the wounded animal."

He added, "We don't know if Natufian hunters had the bow and arrow, or just spears."

The mountain gazelles targeted by the Near Eastern hunters probably weighed between 39 and 55 pounds, so a strong adult "could carry an entire carcass over his shoulders without much trouble."

But the bag's owner wasn't necessarily a man; women are thought to have been in charge of plant gathering. The tools, therefore, either belonged to a woman hunter-gatherer, or work activities were more gender-blind than thought during prehistoric times, Edwards theorized.

Francois Valla, director of the French Research Center in Jerusalem and a noted archaeologist, told Discovery News that similar ancient clusters of tools have been excavated, but this latest one is "the most spectacular of them all."

"The clustering of these items is due to a decision made by some Natufian individual," Valla said. "As such, it is a rare testimony of the behavior of a person 14,000 years ago."

The toolkit's showpiece item, its double-bladed sickle, is now on display in the museum of the Faculty of Archaeology & Anthropology at Jordan's Yarmouk University.

Small group of US experts insist global warming not man-made

Small group of US experts insist global warming not man-made

The moon is seen above the "Feegletscher" (Fairy Glacier), near the ski resort of Saas-Fee, in Switzerland. A small group of US experts stubbornly insist that, contrary to what the vast majority of their colleagues believe, humans may not be responsible for the warming of the planet Earth.

A small group of US experts stubbornly insist that, contrary to what the vast majority of their colleagues believe, humans may not be responsible for the warming of the planet Earth.

These experts believe that global warming is a natural phenomenon, and they point to reams of data they say supports their assertions.

These conclusions are in sharp contradiction to those of the United Nations Intergovernmental Panel on Climate Change (IPCC), which reached its conclusions using largely similar data.

The UN body of about 3,000 experts, including several renown US scientists, jointly won the award with former US vice president Al Gore for their work to raise awareness about the disastrous consequences of global warming.

In mid-November the IPCC adopted a landmark report stating that the evidence of a human role in the warming of the planet was now "unequivocal."

Retreating glaciers and loss of snow in Alpine regions, thinning Arctic summer sea ice and thawing permafrost shows that climate change is already on the march, the report said.

Carbon pollution, emitted especially by the burning of oil, gas and coal, traps heat from the Sun, thus warming the Earth's surface and inflicting changes to weather systems.

A group of US scientists however disagree, and have written an article on their views that is published in The International Journal of Climatology, a publication of Britain's Royal Meteorological Society.

"The observed pattern of warming, comparing surface and atmospheric temperature trends, doesn't show the characteristic fingerprint associated with greenhouse warming," wrote lead author David Douglas, a climate expert from the University of Rochester, in New York state.

"The inescapable conclusion is that human contribution is not significant and that observed increases in carbon dioxide and other greenhouse gases make only a negligible contribution to climate warming," Douglas wrote.

According to co-author John Christi from the University of Alabama, satellite data "and independent balloon data agree that the atmospheric warming trends do not exceed those of the surface," while greenhouse models "demand that atmospheric trend values be two to three times greater."

Data from satellite observations "suggest that greenhouse models ignore negative feedback produced by clouds and by water vapor, that diminish the warming effects" of human carbon dioxide emissions.

The journal authors "have good reason, therefore, to believe that current climate models greatly overestimate the effects of greenhouse gases."

For Fred Singer, a climatologist at the University of Virginia and another co-author, the current warming "trend is simply part of a natural cycle of climate warming and cooling that has been seen in ice cores, deep sea sediments and stalagmites . . . and published in hundreds of papers in peer reviewed journals."

How these cyclical climate take place is still unknown, but they "are most likely caused by variations in the solar wind and associated magnetic fields that affect the flux of cosmic rays incident on cloudiness, and thereby control the amount of sunlight reaching the earth's surface and thus the climate."

Singer said at a recent National Press Club meeting in Washington that there is still no definite proof that humans can produce climate change.

The available data is ambiguous, Singer said: global temperatures, for example, rose between 1900 and 1940, well before humans began to burn the enormous quantities of hydrocarbons they do today. Then they dropped between 1940 and 1975, when the use of oil and coal increased, he said.

Singer believes that other factors -- like variations of solar winds and terrestrial magnetic field that impact cloud formations and the amount of sunlight reaching the Earth's surface, and thus determining the temperature -- are much more influential than human-generated greenhouse gas emissions.

Japan scientists develop fearless mice

Japan scientists develop fearless mice

In this undated photo released by Tokyo University's Department of Biophysics and Biochemistry Graduate School of Science, a genetically modified mouse approaches a cat in Tokyo. Using genetic engineering, scientists at Tokyo University say they have successfully switched off the rodents' instinct to cower at the smell or presence of cats, showing that fear is genetically hardwired and not leaned through experience, as commonly believed.

Cat and mouse may never be the same. Japanese scientists say they've used genetic engineering to create mice that show no fear of felines, a development that may shed new light on mammal behavior and the nature of fear itself.

Scientists at Tokyo University say they were able to successfully switch off a mouse's instinct to cower at the smell or presence of cats — showing that fear is genetically hardwired and not learned through experience, as commonly believed.

"Mice are naturally terrified of cats, and usually panic or flee at the smell of one. But mice with certain nasal cells removed through genetic engineering didn't display any fear," said research team leader Ko Kobayakawa.

In his experiment, the genetically altered mice approached cats, even snuggled up to them and played with them. Kobayakawa said he chose domesticated cats that were docile and thus less likely to pounce.

Kobayakawa said his findings, published in the science magazine Nature last month, should help researchers shed further light on how the brain processes information about the outside world.

Kim Dae-soo, a neural genetics professor at the Korea Advanced Institute of Science and Technology in Seoul, who was not involved in the research, said Kobayakawa's research could explain further what fear is, and how to control it.

"People have thought mice are fearful of cats because cats prey on them, but that's not the case," Kim said.

"If we follow the pathway of related signals in the brain, I think we could discover what kind of networks in the brain are important for controlling fear."

Run of the Mill: Finding galactic building blocks in early universe

Run of the Mill: Finding galactic building blocks in early universe

For more than 3 decades, astronomers have scoured the skies for tiny, ultrafaint galaxies that could be the early building blocks of the massive galaxies common in the universe today. Now researchers report that they have found 27 remote galaxies that appear to fill the bill.

 

LITTLE GUYS. A glow of hydrogen gas emanates from a population of low-mass, weakly star-forming galaxies believed to be the building blocks of bright, present-day galaxies.

 

These galaxies have low rates of star formation and appear to be 20 times as numerous as other, larger galaxies previously found from the same early era, when the universe was just 2 billion years old. Their properties suggest that the newly discovered bodies are part of a long-sought population of average-size galaxies that merged to form larger galaxies like the Milky Way.

Using the European Southern Observatory's Very Large Telescope (VLT) in Paranal, Chile, Michael Rauch of the Carnegie Observatories in Pasadena, Calif., and his colleagues studied a tiny patch of sky for an unprecedented 92 hours, recording extraordinarily faint levels of a particular wavelength of light. That wavelength, known as Lyman-alpha, is emitted when energetic radiation from newborn, massive stars bombards hydrogen gas within galaxies, causing the gas to glow.

As observed from Earth, the ultraviolet Lyman-alpha radiation is shifted to longer, or redder, wavelengths by the expansion of the universe. The more distant the galaxy, the greater the redshift. The redshifted Lyman-alpha radiation detected by Rauch and his colleagues indicates that the 27 galaxies reside nearly 12 billion light-years from Earth, the team will report in the March 1, 2008 Astrophysical Journal.

The weak Lyman-alpha emission indicates that these galaxies are forming stars at a sluggish rate, equaling a tenth of the sun's mass every year. In addition, the density of the galaxies found in such a small area of sky suggests that the galaxies are about 20 times as common as a well-documented collection of brighter but equally remote galaxies that make stars more prodigiously. Those galaxies, known as Lyman-break, were found using a different detection technique. They are not only rarer than the new group but also more massive, Rauch says.

Hints of the newly found building blocks for larger galaxies emerged when astronomers began studying the detailed spectra of the brilliant beacons known as quasars. The spectra revealed that as the quasar light journeyed to Earth, some of the radiation was absorbed by intervening blobs of hydrogen gas. Rauch and his collaborators now suggest that those blobs, previously revealed only as shadows on the quasar light, are the small, Lyman-alpha-emitting galaxies his team has detected.

Images of another sky region, studied intensively with the Hubble Space Telescope and known as the Hubble Ultra Deep Field, may also show signs of these run-of-the-mill galaxies, notes Rychard Bouwens of the University of California, Santa Cruz.

The 92-hour VLT study, pieced together from odd corners of the night over several years, "is a heroic observation, and I hope that it represents the start of an era rather than something the world decides is too expensive to repeat," comments David Weinberg of the Ohio State University in Columbus. Although the objects are detected at a low signal-to-noise ratio and the sample is small, the team "most likely is detecting star formation in small galaxies, mapping out the iceberg of which the previously known Lyman-break galaxies are the tip," says Weinberg. "Knowing what is going on for these more run-of-the-mill systems will be valuable for testing theories of the [early] galaxy population."

The observation bodes well for finding many more of the building blocks with ground-based telescopes, rather than having to conduct such studies in space, says Rauch.