Friday, September 4, 2015

Borneo mountain hotbed of young biodiversity

Mount Kinabalu (Source: J. Kong/Sabah Parks)

 A species of stalk-eyed fly (Teleopsis pallifacies that lives along streams, such as the Kemantis waterfall.

 This jumping spider (Myrmarachne malayana) mimics ants, presumably to avoid being predated on. Its large jaws can be seen ready to snap at its own prey. It is a widespread species that lives both on the mountain and on the lowlands.
  

On the tip of Borneo stands the World Heritage-listed Mount Kinabalu, which like other tropical mountains is known to be a hotbed of biodiversity.
 
Only now, however, have researchers carried out a systematic DNA analysis of biodiversity on the mountain to get an insight into how it evolved.

By comparing organisms found on the mountain with those found elsewhere, they not only estimated when the species evolved, but where they came from.

The analysis follows collection of tens of thousands of plants, animals (mainly insects, spiders and mites) and mushrooms, many of which are unique to the mountain, says lead author, Professor Menno Schilthuizen, an evolutionary biologist at the Naturalis Biodiversity Center and Leiden University in the Netherlands.

The findings suggest that most of the species have an average age of only 1.5 million years, while the mountain itself is at least six million years old, says Schilthuizen.

The discovery that most of the species on Mount Kinabalu are so much younger than the mountain itself puts another nail in the coffin of the idea that tropical mountains are refuges for plants and animals that have been around for a very long time, says Schilthuizen.

"For example, tablelands in Venezuela are called 'lost worlds'," he says. "The idea is that on top you have these ancient lineages that have been outcompeted elsewhere."

He says about two thirds of the species on Mount Kinabalu are descendants from species at lower altitudes, that became adapted to cooler conditions," he says.

The rest live higher on the mountain and have come from spores, seeds and tiny animals, transported from further afield by high aerial currents.

"There's constantly a soup of very tiny organisms floating in the air and that's a very important source for colonisation for islands and high mountains," says Schilthuizen.

Because the temperature and environment change rapidly as you go up a mountain, this means that niches for different species change similarly rapidly, which means species may be restricted to certain areas, such as the summit of the mountain.

As the climate warms, such species will have limited 'room to move', says Schilthuizen, and may be threatened with extinction.

The findings are published today in the journal Nature.

Earth has three trillion trees, and falling

There are about three trillion trees on Earth, roughly 422 for every person and eight times more than previously estimated, researchers say.
 
A 15-nation team led by Yale University experts used a combination of old-fashioned headcounts and state-of-the-art satellite and supercomputer technology to produce what they claim is the most comprehensive tree census ever.

"I don't know what I would have guessed, but I was certainly surprised to find that we were talking about trillions," says the study's lead author Thomas Crowther of the Yale School of Forestry and Environmental Studies in Connecticut in the United States.

But there was bad news, the researchers reported in the journal Nature.

The calculation revealed that tree cover had nearly halved since the start of human civilisation.
And the pace of deforestation has not abated: our species is currently felling some 15 billion trees every year, the study found.

The team based their research on verified tree counts from some 400,000 forest plots.

They then used satellite imagery to determine how factors like climate, topography, vegetation, soil conditions and human impact affected tree density.

Developing models to estimate tree numbers at regional levels, they then drew a global map of Earth's estimated 3.04 trillion trees.

"The highest densities of trees were found in the boreal forests in the sub-arctic regions of Russia, Scandinavia and North America," the researchers say.

"But the largest forest areas, by far, are in the tropics, which are home to about 43 percent of the world's trees."

The bad news

The team's calculations revealed that of all the factors impacting tree numbers, human activity had by far the biggest effect, largely through deforestation and land-use change.

There has been in total a 46-percent drop in tree numbers since humans began to clear land to plant seeds, the study found.

"In short, tree densities usually plummet as the human population increases," the scientists say.
"We've nearly halved the number of trees on the planet, and we've seen the impacts on climate and human health as a result," says Crowther.

"The study highlights how much more effort is needed if we are to restore healthy forests worldwide."

Apart from offering oxygen, fuel and shelter, trees store important quantities of carbon, which, if released, contribute to global warming.

Sunday, August 23, 2015

Temple of the Feathered Serpent, Teotihuacan



View of the tunnel using a laser scanner. Image: INAH


 A reconstruction of the Ciudadela. The Temple of the Feathered Serpent can be seen at the upper center, with the Adosada directly in front of it.

At a recent INAH press conference on the Tlalocan project, it was announced that a substantial offering and three chambers have been discovered at the far end of a tunnel discovered under the Temple of the Feathered Serpent at Teotihuacan, Mexico. The tunnel had been closed off around 1,800 years ago by the occupants of the city, and was only re-discovered by chance.
Lead archaeologist Sergio Gómez Chávez gave a brief account of the work that began at Teotihuacan 11 years ago.

An extensive offering
It started, he explained, when heavy rains revealed a small cavity, that then became a shaft leading to a tunnel of approximately 120m long under the Temple of the Feathered Serpent. Recently, at 103 feet along the tunnel the archaeologists discovered an abundant offering covering a space of 4m wide by 8m in length. Located at a depth of 18 metres, this offering, known as “number 48″, may well be an announcement that something extremely important lies within the next three chambers, perhaps says Gómez Chávez, the people linked to the power structure of Teotihuacan. 

The offering is composed of four green stone anthropomorphic sculptures, dozens of large snails from the Gulf of Mexico and Caribbean, thousands of beads made from various materials, imported Guatemalan jade, rubber balls, the bones and fur of big cats, beetle skeletons, pyrite discs, and a wooden box containing worked shells.

“As we continue to explore, the offerings are becoming increasingly numerous, rich and varied,” said Sergio Gómez Chávez.

Apart from the most recent deposit, in the last sections of the tunnel the archaeologists recovered “more than 4,000 objects of wood in a perfect state of conservation,” over 15 thousand seeds of different plant remains and remnants of skin, possibly human, to be submitted for analysis.

The Miccaotli phase
All this ritual activity was carried out between 150-200 AD, in the Miccaotli phase, when Teotihuacan was modified in three stages, and previous structures demolished. At the Citadel remnants of a previous building to the Temple of the Feathered Serpent pyramid were discovered, as well as a  ball game court, 137m in length, and 100m from the entrance of the tunnel.

“We have all the evidence that corroborate that the Citadel was used as a sanctuary to recreate not only the creation myths, but also for political purposes. The powerful people almost certainly used this space to justify their rule” explained Gómez Chávez.


Tuesday, August 11, 2015

A CONTEMPORARY DERIVATIVE OF A PORTOLAN CHART.



This map of the Black Sea takes its coastal outline and names from a portolan chart, but it omits the navigational rhumb lines. It is from a manuscript island book, the Insularum illustratum, by Henricus Martellus Germanus, who worked in Florence ca. 1480-96.

To the historian of late medieval and early modern European cartographyl the portolan charts are fundamental documents, if mysterious in their origin and precocious in their precision. Their importance has long been acknowledged, and "The First True Maps" was the enthusiastic title of an article by Charles Raymond Beazley in 1904. More recently, Armando Cortesao considered the "advent of the portolan chart ... one of the most important turning points in the whole history of cartography." Alberto Magnaghi went further, describing them as a unique achievement not only in the history of navigation but in the history of civilization itself. For Monique de La Ronciere the work of the first named practitioner, Pietro Vesconte, was so exact that the Mediterranean outlines would not be improved until the eighteenth century. In terms of the economic history of cartography, Vesconte and his contemporaries may have been the first, in the plausible opinion of a recent writer, "to pursue mapmaking as a full-time commercial craft.

From the earliest extant copies, probably a little before 1300, the outline they gave for the Mediterranean was amazingly accurate. In addition, their wealth of placenames constitutes a major historical source. Their improvement over the Ptolemaic maps relating to the same area is obvious at a glance, and the North African coast with its clearly defined Syrtes is the most striking advance. Moreover, the Ptolemaic maps began to circulate widely through Europe only in the fifteenth century, by which time the portolan charts were well established. Though a linear scale was implied on Ptolemy's maps by their grid of longitude and latitude, the medieval sea charts were the first cartographic documents to regularly display one. This should be contrasted with the history of European topographical mapping, which shows that the first local map since Roman times to be drawn explicitly to scale was a plan of Vienna dating from about 1422.8 As P. D. A. Harvey further points out, virtually no local maps produced during the period under discussion, that is up to 1500, made "the slightest attempt at consistency of scale.

An even greater gulf divided the portolan charts from the medieval mappaemundi, the cartographic content of which was largely shaped by their theological message. It is worth recalling that the earliest known portolan chart is thought to be almost exactly contemporary with the Hereford world map. It cannot be claimed, of course, that the portolan charts were totally free from what today we call superstition, but neither were medieval sailors. Yet Prester John, the four rivers of paradise, the mythical Atlantic islands, and other legendary features found on some charts are all placed in the little-known interior or around the periphery. The continental coastlines that constitute the charts' primary purpose are in no way affected. The unidentified author of the Genoese world map of 1457, whose depiction of the Mediterranean is based on the portolan charts, neatly sums up the chartmakers' attitude: "This is the true description of the world of the cosmographers, accommodated to the marine [chart], from which frivolous tales have been removed."

The medieval sea chart is the clearest statement of the geographic and cartographic knowledge available in the Mediterranean. Occasionally the coverage was extended to the East, as in the case of the Catalan atlas. Contact with China, however, ceased after the mid-fourteenth century with the collapse of that Tatar empire at which the Polos had marveled. But in the West the portolan charts of the fourteenth and fifteenth centuries provide the best, and at times the only, documentation of the first chapter of Renaissance discovery-the exploration of the Atlantic islands and the charting of Africa's entire west coast. The Spanish and Portuguese seaborne empires whose foundations were to be laid by Christopher Columbus and Vasco da Gama were the fruits of these preparatory voyages.

The medieval mappaemundi are the cosmographies of thinking landsmen. By contrast, the portolan charts preserve the Mediterranean sailors' firsthand experience of their own sea, as well as their expanding knowledge of the Atlantic Ocean. They are strikingly original, signaling, as Gerald R. Crone pointed out, a "complete break with tradition." Whatever their antecedents might have been, these cannot be identified with any confidence today; but this is only one of the many unanswered questions these documents pose. How was the prototype constructed and when? How were copies manufactured for some four hundred years without steadily increasing distortion? Did the Catalans influence the Italians, or vice versa? And most fundamental of all, what was their function?


Monday, July 20, 2015

Mysterious Viking Sword Made With Technology From the Future?


By Tara MacIsaac, Epoch Times


The Viking sword Ulfberht was made of metal so pure it baffled archaeologists. It was thought the technology to forge such metal was not invented for another 800 or more years, during the Industrial Revolution.

About 170 Ulfberhts have been found, dating from 800 to 1,000 A.D. A NOVA, National Geographic documentary titled “Secrets of the Viking Sword”, first aired in 2012, took a look at the enigmatic sword’s metallurgic composition.

In the process of forging iron, the ore must be heated to 3,000 degrees Fahrenheit to liquify, allowing the blacksmith to remove the impurities (called “slag”). Carbon is also mixed in to make the brittle iron stronger. Medieval technology did not allow iron to be heated to such a high temperature, thus the slag was removed by pounding it out, a far less effective method.

The Ulfberht, however, has almost no slag, and it has a carbon content three times that of other metals from the time. It was made of a metal called “crucible steel.”

It was thought that the furnaces invented during the industrial revolution were the first tools for heating iron to this extent.

Modern blacksmith Richard Furrer of Wisconsin spoke to NOVA about the difficulties of making such a sword. Furrer is described in the documentary as one of the few people on the planet who has the skills needed to try to reproduce the Ulfberht.

“To do it right, it is the most complicated thing I know how to make,” he said.

He commented on how the Ulfberht maker would have been regarded as possessing magical powers. “To be able to make a weapon from dirt is a pretty powerful thing,” he said. But, to make a weapon that could bend without breaking, stay so sharp, and weigh so little would be regarded as supernatural.

Furrer spent days of continuous, painstaking work forging a similar sword. He used medieval technology, though he used it in a way never before suspected. The tiniest flaw or mistake could have turned the sword into a piece of scrap metal. He seemed to declare his success at the end with more relief than joy.

It is possible that the material and the know-how came from the Middle East. The Volga trade route between the Viking settlements and the Middle East opened at the same time the first Ulfberhts appeared and closed when the last Ulfberhts were produced.

The article, ‘Mysterious Viking Sword Made with Technology from the Future’ was originally published on The Epoch Times,

Researchers confirm: The Largest Pyramid in Mexico has been found


Aingi Oranais
Zon Staff

Researchers discover immense pyramid in Mexico, larger than Teotihuacan’s Pyramid of the Sun. Researchers in Mexico have discovered a Pyramid that, according to initial measurements, is larger than the Great Pyramid of the Sun in Teotihuacan. Initial excavations were done in 2010.

The Pyramid, 75 meters in height, was explored by specialists from the National Institute of Anthropology and History (INAH) on the acropolis of Tonina, Chiapas, estimated to be around 1700 years old.

Emiliano Gallaga, director of the archaeological zone, explained that work has been done in the last two years, and by means of a “three-dimensional, researchers verified that in the northeastern part of the site, stands one of the largest construction in Mesoamerica, comparable in size only to great Mayan cities like Tikal and El Mirador in Guatemala.

Another features which makes this “unique” pre-hispanic structure stand out are the seven platforms which integrate it and were specific spaces intended to serve as palaces, temples, housing and administrative units. It is a unique structure for various specific functions within the social, political, economic and religious structure, which is not repeated in any other archaeological site of the Mayan world stated researchers from INAH.

“It’s a big surprise to see that the pyramid was done almost entirely by pre-Hispanic architects and therefore is more artificial than natural. “This is because it was believed that the entire structure was a natural hill, but recent evidence has revealed that the structure was almost entirely built by ancient inhabitants.

Archaeologists added that the pyramid is bigger than we had anticipated. The structure is connected by roads located on top of surrounding elevations.

Gallaga added that, after all of the information, we can confirm that this pyramid exceeds in height the pyramid of the Sun at Teotihuacan which measures 65 meters. INAH researchers have determined that the city center had an architectural continuity between 10 and 12 hectares, which is the double of what was previously thought and mainly corresponds to the south facade of the Acropolis, one of the most important Mayan areas known to researchers.

Sunday, July 5, 2015

Madaba Map

Discovered in a church in Madaba, Jordan, in 1884, the Madaba Map is the oldest surviving cartographic depiction of the Holy Land. Created in the form of a mosaic it dates to somewhere between A.D. 560-565 and originally showed an area that stretched from southern Syria to central Egypt. By the time it was discovered much of the map was already gone, however its remains include a detailed depiction of Jerusalem. "The bird's-eye view shows an oval-shaped walled city in the very center of the map with six gates and twenty-one towers, the colonnaded main thoroughfare … and thirty-six other identifiable public buildings, churches and monasteries," writes Jerome Mandel in an article published in the book "Trade, Travel and Exploration in the Middle Ages: An Encyclopedia" (Routledge, 2000). At the time it was created the Byzantine Empire ruled the Holy Land. 

On the sixth-century mosaic map of Palestine that paved the floor of a church in Madaba in Transjordan, Jerusalem holds a dominant position (Avi-Yonah 1954: 50-60, plate 7, nos 52-3). The colonnaded main street of Hadrian's Aelia Capitolina, the cardo maximus, is clearly visible, running southwards from what is now the Damascus Gate in the direction of Mount Zion, which lay outside the southern city wall until changes brought to the line of the city wall at the time of the Empress Eudocia in the middle of the fifth century. In a distinguished central position on the west side of this street, breaking the colonnade, are the steps leading to the propylea of Constantine's basilica; its three doorways are clearly visible. The complex of buildings on Golgotha is the largest edifice depicted, and is clearly meant to be seen as the focal point of the city, culminating in the domed rotunda which by that date covered the Holy Sepulchre. The steps leading directly to the main entrance of the basilica off the street recall Eusebius' description of its fronting onto the main thoroughfare. 

The deliberate emphasis on the central position of the Constantinian buildings at Jerusalem on the Madaba map reflects the importance of the Constantinian foundations. If Jerusalem was for the Christians the centre of the world, then the centre of Jerusalem itself could only be the place of Christ's death and resurrection. By contrast with the church of the `Upper Room' where the Jerusalem community had worshipped down the ages, tucked away outside the city on Mount Zion, Constantine's Holy Sepulchre was on the site of the Hadrianic temenos, alongside the forum and near the central crossroads, approached by an impressive flight of steps from the main thoroughfare; the new Christian monuments, and no longer the pagan temples, were the highlights of the city. 

Thus fourth-century Jerusalem saw Christianity symbolically transported from its place outside the walls to the very heart of the city. Roman Aelia was now the Christian Jerusalem. It was Constantine's creation of the `new Jerusalem' of Rev 21:2 - `And I John saw the holy city, new Jerusalem, coming down from God out of heaven, prepared as a bride adorned for her husband' - which lay at the heart of the Holy Land's emergence as a goal of pilgrimage in the fourth century (Hunt 1982).