More than bear bones: Awesome Atapuerca

If it had not been for an English mining company, Europe's oldest human species would still be undiscovered, the fossil remains of over a million years trapped inside a Spanish hill that turned out to be riddled with holes and paleoanthropological significance. Atapuerca, a rural parish to the east of Burgos, became a magical name among archeologists in 2007 when the jawbone of an adolescent was shown to belong to a previously unknown hominid species, tuning on its head the previous theory of human presence in Europe.

At the dawn of the 20th century, Basque industry required iron and coal in larger amounts than existing mines in Asturias and León were then able to provide. The Sierra de Demanda in the central Iberian mountain system proved to offer an alternative. The rail route built to link the new mines with the north coast passed through the district of Atapuerca. "Rather than go around the sierra, which as you can see is not very big, these English engineers decided to blast straight through," explains our guide David, himself an archeologist at the site, as the bus picks its way through the green wheat fields between the rivers Arlanzón and Vena that flank the flat-topped Atapuerca range. Some have speculated that the motive was not to build a straighter track, but rather a desire for a limestone bonus once the trench had been blasted deep through the rock, almost, but not quite, straight like a noncommittal smile. The cutting is gated at each end. There is something of Jurassic Park about the site. There has to be something both mysterious and precious inside.

That limestone karst had offered shelter from the elements, safety from animals (and other humans?), natural traps for hunters and even walls to paint for people over a million years. These humans were Homo antecessor - the new species to which that 1.2-million-year-old jawbone belonged - Homo heidelbergensis (previously considered the first Europeans), Homo neanderthalensis and Homo sapiens, who were here right up to the Iron Age, a fact attested to by their zig-zag patterned ceramics. Caves had formed by the action of water and been used by men before successively being filled with sediments, the layers of which are now being skimmed off and analyzed to piece together the history of humankind at Atapuerca.

Did a bowler-hatted mining engineer or the local navvies carving out the railway cutting stop to wonder about the glints of white bone fragments, visible in the galleries that open directly on to the trench? It seems not. The metallurgical railway long gone, the next link in the chain is Trinidad de Torres, a mining engineer who was looking for cave bear fossils as part of his PhD thesis, David continues. "Trino," our unlikely hero, fell in with speleologists, who told him where he could find some bear bones; he found many, and something more. In 1976 Torres went to the anthropologist Emiliano Aguirre with what he thought were human fossils. By 1980 the Sima de los Huesos (Pit of Bones), accessible via a 500-meter crawl through the rock and now a sanctuary only open to the chosen few, became a focus of increasingly feverish archeological activity and would eventually yield the cranium of Miguelón (a heidelbergensis who has become a symbol of the area around Atapuerca) and signs that hundreds of thousands of years ago, man symbolically deposed of its dead.

More holes within Atapuerca's "Swiss cheese" were uncovered, David reveals. Like Galería, a pit which sometime between 200,000 and 400,000 years ago was used as a trap by hunters. Fooled by the judiciously placed vegetation, animals such as deer would fall, perhaps breaking a limb or dying outright at the bottom of this 16-meter chimney. Given that the pit linked to other caves, "would the hunters stay there to feast," our guide enquires? With cave lions or saber-toothed tigers on the loose, the answer is a definite no. What to do? How to haul a great carcass out of the pit? "We have found animal skulls, ribs and vertebrae in there," the guide explains. "But no legs." It seems that even the earliest Iberians were ham freaks.

Stone and later flint axes would be used to butcher the prey. But how can we know when a stray tool or a piece of jawbone, impossible to DNA test due to its great age, is from a certain period? Here a wonderful thing comes into play, explains David. Over the Earth’s history the poles periodically change - north becomes south and vice versa. Iron deposits in rock and sediment can be analyzed and their alignment shown to swing one way and then the other, allowing archeologists and paleontologists to equate the passage of time with an object’s position in a geological formation. Awe at or.

Why here? The area looks like so many other tracts of land across the Castilian meseta: rolling wheat fields, interrupted by craggy hilltops covered in scrub. In fact, Sierra de Atapuerca is in the Bureba Corridor, a geographic passage linking the Ebro and Duero river basins, with the mountains of Sierra de la Demanda to the south and the foothills of the Cantabria Range to the north. Particularly in times of glaciation, this would be an inevitable place of passage for herds of herbivores crossing the northern half of the Iberian peninsula. Groups of four different human species "have walked, slept, hunted, gathered and eaten across the beautiful landscapes that form Sierra de Atapuerca. Horses, rhinos, bison, fallow deer, wild boars, deer, bears, tigers, lynxes, lions and many other animals have shared forests of evergreen oak, juniper, English oak, chestnuts, birch , beech, pine trees and riverine coppices," in the words of the Atapuerca Foundation's excellent website.

So what is left to be discovered? Funnily enough, the 2013 excavation season started this month with the hope of nailing a Neanderthal, that species which has left such abundant remains across the Iberian peninsula. Atapuerca operatives have established beyond all doubt that the heavy-browed human was present at and near the site, thanks to finds of the Neanderthal calling card: the flint ax. But bones to seal the full four-species deal have been stubbornly absent so far. Decades of work lie ahead, and the fortuitous nature of its discovery and the vast amount of sediment still to be excavated means that many more surprises could be in store in Atapuerca - and in who knows how many as-yet unnamed sites across the world. It just needs a railway engineer or a fossil-hunting student to break the seal on an unknown truth.

Comments

[Publicado por: Ivan]

As nice blog:)

[Publicado por: connexion]

in my opinion, the is an awesome arhitecture in mexic and spain some images is here: http://conexion.ro
involve a lot of work