Thursday, June 14, 2012

Romney's Wacky Jobs Chart

Job chart in Romney’s economic plan seems wrong

I was asked to comment on the speech Mitt Romney made in front of the Business Roundtable, so I decided to do some light background reading: Believe in America: Mitt Romney’s Plan for Jobs and Economic Growth.(pdf)

I noticed something odd in the jobs section of the plan—this chart (ripped directly from the Romney PDF):




I know jobs numbers and recoveries, and these looked wrong to me. For one, the absolute peak-to-trough employment loss following 2007’s Great Recession was 8.8 million jobs (between Jan. 2008 and Feb. 2010)  not the 8.9 million that the chart claims.

And given that this is the peak job loss, this means, by definition, that anything measured after this trough couldn’t be negative, as the chart implies. I also know that the U.S. economy didn’t begin adding jobs after the 2001 recession until the second half of 2003, so the 2001 numbers looked off, too.

So I decided to do the chart correctly—actually show job losses during the official recessions (i.e., not just employment peak to trough) and the 24 months following and sure enough:



Romney’s numbers are all slightly off, which is odd.

Odder is that the respective performance of the recoveries following the 2001 and 2007-2009 recession are reversed. Look closely at the the last two sets of bars in the respective figures.
The Romney chart  has jobs growing in the first 24 months of recovery following the 2001 recession, but shrinking in the first 24 months following the 2007-2009 recession. That’s the opposite pattern of what actually occurred—jobs shrank for the first two years after the 2001 recession and grew modestly in the first two years after the 2007-2009 recession.

I’ll note that we also tried to match the Romney numbers with quarterly data, with household-survey employment counts, with household-adjusted-for-payroll concepts survey data … nothing worked.

A little curious as to what’s going on here.

And since there’s been lots of discussion about the relative health of the private and public sectors, here’s the correct graph for private-sector jobs only.


The Meaning of Occupy

Revealing the Failure of 21st Century U.S. Capitalism
by PETER BOHMER

The Occupy movement in the United States is part of a global upsurge that began in Tunisia in late 2010, spread to Egypt and the Middle East, Wisconsin, Chile, Spain, Greece, Wall Street and the rest of the United States and now Quebec. I focus on the United States, particularly the Pacific Northwest where I have been an active participant.

I would like to acknowledge the moment. So often, we are alienated, or apathetic to the economic and social injustices taking place. This is a hopeful period when resistance and uprising in one place have resonated and spread. In the United States, we are living in a period of obscene inequality of income and wealth, a broken economic and political system that needs to be transformed not patched up. The income of the top 1% today is 42 times the bottom 90%, three times greater than the already high income inequality of 1979. 50 million people do not have health insurance, 1 in 3 are poor or near poor. Millions have lost their homes. Over 2 million people are in prison, disproportionately Black and Latino.

Over 20 million are unemployed; the rate for Blacks is twice that of whites. According to the New York Times of June 6th, 2012, of those who graduated from high school between 2009 and the present and who are not in college full time, one in six have full time jobs. For recent college graduates it’s not as bad but there is an ongoing crisis of unemployment and underemployment. The unemployment rate for young adults in Egypt, Spain, Greece and Portugal is even worse and has been an important factor in their uprisings. Whether we are living in a full-fledged global economic crisis is debatable, but the much higher than normal rates of unemployment is striking. The ongoing high unemployment rates and poor job prospects with high levels of student debt are an important factor in the participation and support for the Occupy Movement.

There was significant participation of veterans from Iraq and Afghanistan in the physical occupation of public space, Occupy, Olympia, Seattle and Portland, which peaked in October and early November 2011 and were closed down by various police forces over the next month. Most of the vets participating couldn’t find jobs and many were suffering from PTSD, often undiagnosed —another symptom of our imperialist system and poorly functioning health-care system.

The majority of the people who lived in tents at the Occupy Olympia site lacked access to health care, regular jobs and housing. Many had felony convictions, a testament to the U.S. having the highest prison rate in the world. Felons are openly discriminated against in getting jobs, housing, and higher education (see Michelle Alexander, The New Jim Crow.)

Those active in the Occupy Movement were motivated by unemployment and housing foreclosures, by the growing inequality of income and wealth, by the corporate domination of our daily lives, and corporate control of the government. There is a lot of anger at the decline in the social safety net, the bailout of banks and not people, and the “Citizens United” Supreme Court decision.

The Occupy Movement has forced public discussion and debate of these issues. Growing numbers, particularly young people, have begun to feel that they can and should act, that their actions matter. Through actions and media attention and by resonating with the lived experiences of the “99%”, the Occupy Movement has brought the economic and political crisis out of the closet.

By economic crisis, I do not necessarily mean a full-blown economic crisis in the Marxist sense. Even if profits are up; the economy is not working for working people and the unemployed. By political crisis I do not mean we are in a possible revolutionary situation, such as Greece, but rather there is a rapid loss of legitimacy of the Democrats and Republicans, of the Supreme Court and a growing awareness of the ongoing destruction of democracy and the growing surveillance state.

Prefigurative Movements

Among activists in the Occupy Movement, a very popular ideology is anarchist, although increasingly an anarchism not hostile to Marxism. I agree with Grubajic and Lynd in Wobblies and Zapatistas, that we need to end the sectarianism and division between anarchists, Marxists and participatory socialists. Although, I would not call the Occupy Movement as a whole, anti-capitalist, many of the participants identify that way. In Seattle, on May Day, 2012, there was an overtly anti-capitalist march, organized by Occupy Seattle, of 800 people.

A priority in the occupations has been meeting the needs of poor people for medical care, housing, food, security and safety, and community and political discussion and education. There was a serious effort by activists to provide these services on-site and to encourage the active participation of the residents of the occupation. These actions show the failure of the current capitalist system to provide for human needs; its discarding of poor people. We made visible the human costs of the U.S. political economy.

A community and democratic structure, although somewhat chaotic and imperfect and with few resources, provided a place for people to live, to learn, and be secure. There has been the development of community in the Occupy Movement; meaningful discussions between people who usually don’t talk to each other, of people looking out for each other. There were problems of limited and difficult communication between activists, mainly students or college educated, with the homeless, but it’s a beginning.

There were fights and drug problems, and problems of male dominance and sexual violence. Nonetheless, I disagree with the commonly held point of view that the Occupy Movement has been weakened by the large participation of homeless people. They are “the canary in the coal mine”. Over time, many identified as protesters.

Although imperfect, this is a concrete demonstration on a small scale of key values of a participatory socialist system. The meeting of basic human needs was a priority of the occupations and was universally understood as a human right. There was discussion of how to move from a makeshift medical tent on-site to the development of a fully functioning and accessible free health clinic. There was sharing of tents and clothing and resources.

There has been an emphasis on direct democracy, encouraging all voices to be heard with consensus decision-making. While this sometimes led to the general assembly being unable to reach decisions, it reflected a key value of the occupiers, of participatory democracy, and horizontal and non-hierarchical decision making. There was a rotation of tasks and facilitators at meetings. There was an emphasis on building an alternative community, ourselves. There was less emphasis on demanding resources from the state. Many participants believe in building a new society with a different economy, politics, culture, and interpersonal relationships–by having these alternative small communities spread until they became a new society.

Limitations

By the time of the December, 2011 police raid, participation at Olympia, Occupy had declined. The wet and cold weather was a major cause as was the large time commitment. Since then the Occupy Movement has not been able to regain its momentum. The lack of structure is a factor as is the lack of a clear strategic way to move forward. Should there be physical occupations of public or private space; or campaigns around specific demands, e.g., stopping housing foreclosures; or direct action and/or demonstration, such as mobilizations against the G-8 in Chicago in May, 2012, or at the upcoming Democratic and Republican Convention? None of these tactics have garnered much enthusiasm or active participation. The anger and awareness about the systemic failures of our system continue as does a growing anti-capitalist consciousness, but there is a lull in activism.

A major problem has been how to build a movement that unites the 99% while simultaneously making central the concerns of the most oppressed–by not having our only talking point be the excess wealth and power of the 1%. How do we build a movement that includes immigrant rights, environmental justice, racial justice, LGBT and reproductive/women rights, anti-war and global justice? Most participants in Occupy are sympathetic to amnesty for undocumented immigrants and against U.S. wars; but these have not been principles nor put forth as demands. A major challenge of Occupy is how to be simultaneously broad, inclusive and principled.

A common criticism has been there have been no demands, especially at a national level. Given the divergence of ideologies– many flavors of reformism and of left radicalism– making demands has been difficult and not desirable at this early stage of the movement. There is a need as this movement develops for demands for non-reformist reforms (see Gorz, Strategy for Labor) to emerge, that campaigns can be built around, where there is national coordination and excitement and passion Full employment with living wage jobs is a possible demand.

In fall, 2011, the Occupy Movement in the U.S. broke through feelings of powerlessness. Six months later, this movement is weaker although the movement against neoliberalism and austerity in Greece and Quebec is growing and powerful. New activists have learned organizing skills and have deepened their political understanding. Stay tuned for the next chapter.

Wednesday, June 13, 2012

TPP secrets: Obama covertly granting more power to multinational corporations

Published: 13 June, 2012 - RT


Despite the White House’s efforts to keep a proposed free trade agreement concealed from the public — and even Congress — an excerpt from the TPP leaked Wednesday reveals that President Obama is prepared to bow to multinational corporations.

The United States has been engaged in discussion with eight Pacific nations to come to agreement on the terms of the proposed Trans-Pacific Partnership, a free trade contract that would allow for a more open system of exchange between the US and less developed nations. Critics have been concerned, however, over how provisions of the project could drive up the price of medications and other goods across the world. The White House’s reluctance to provide details to even leading lawmakers responsible for America’s trade plans has caused a rift within the president’s own political party as his administration remains adamant about protecting the items being heard.

A section of the proposed Trans-Pacific Partnership was leaked to the Web early Wednesday, and its contents suggest that US President Barack Obama was perhaps not so genuine with promises made while campaigning in 2008 and even offers some insight into why his administration has been eerily secretive about the TPP.

Details about negotiations determined during meetings between White House officials and leaders from the eight Pacific nations involved in the TPP have been so hidden from the public that even some members of the US Congress have called on the president to come forth with information. In a leak published this week by the advocacy website Public Citizen, though, it’s made clear that the Obama administration has every intention of backpedaling on previous promises that could largely impact regulations that will directly affect the safety and financial security of millions of Americans and international citizens.

According to the leaked excerpt, the Obama administration has been considering TPP provisions that would allow foreign corporations operating within the United States to appeal regulations on the environment and banking that would be forced on American-owned businesses with no chance of reprieve. While the United States could be sanctioned for failing to impose regulations on American-run businesses, multinational corporations are practically encouraged to do as much because the TPP outlines a clear avenue to file an appeal. If one of the eight Pacific nations chooses to do as much, their plea would be heard by an international tribunal that could overrule US law.

Such key components of the leaked TPP document conflict directly with campaign promises harped by then-candidate President Obama while vying for the White House. Huffington Post reports that during the 2008 campaign, Barack Obama was clear in emphasizing, "We will not negotiate bilateral trade agreements that stop the government from protecting the environment, food safety or the health of its citizens; give greater rights to foreign investors than to US investors; require the privatization of our vital public services; or prevent developing country governments from adopting humanitarian licensing policies to improve access to life-saving medications.”

On the contrary, President Obama is reportedly not so concerned today. Condemning the president over how the TPP could alter intellectual property standards are many critics who fear that the agreement would lead to the monopolization of life-saving drugs and thus propel the prices to an unaffordable amount.

"Bush was better than Obama on this," Judit Rius of Doctors Without Borders Access to Medicines Campaign tells HuffPo. "It's pathetic, but it is what it is. The world's upside-down."

Last month, Senator Ron Wyden (D-Oregon) introduced legislation that specifically targets the Obama administration by demanding that the White House open up on details about the proposed TPP. Despite serving as chair of the United States Senate Finance Subcommittee on International Trade, Customs, and Global Competitiveness, Sen. Wyden has been largely left uninformed about the details of the TPP all while the White House has opened up to the multinational corporations expected to profit through the proposal.

“The majority of Congress is being kept in the dark as to the substance of the TPP negotiations, while representatives of U.S. corporations – like Halliburton, Chevron, PHRMA, Comcast, and the Motion Picture Association of America – are being consulted and made privy to details of the agreement,” said Wyden. The senator’s legislation would require the United States Trade Representative office “to provide documents related to trade negotiations to members of Congress and their staff upon request.”

U.S. trade proposal would let corporations overrule laws

By Stephen C. Webster - RAW Story
Wednesday, June 13, 2012


The Trans-Pacific Partnership (TPP), a forthcoming U.S. trade agreement that looks to solidify a seamless regional economy in the Pacific-rim, would give multinational corporations the power to challenge and even avoid compliance with laws in member countries — including the U.S. — provided a super-national corporate tribunal agrees with their claim.

That’s according to documents leaked this week by the Citizens Trade Campaign, an activist group responsible for leaking TPP proposals on intellectual property last year. The latest leak details a TPP draft chapter on “investments,” which proposes an independent dispute arbitration process that would be empowered to supersede domestic laws or regulatory actions in member states if they are seen as conflicting with the TPP’s framework.

Consumer advocacy group Public Citizen said Wednesday that it “has verified that the text is authentic,” and described the proposals as being fraught with “dangers.”

“It reveals that negotiators already have agreed to many radical terms granting expansive new rights and privileges for foreign investors and their private corporate enforcement through extra-judicial ‘investor-state’ tribunals,” they explained.

“Although TPP has been branded as a ‘trade’ agreement, the leaked text shows that TPP would limit how signatory countries may regulate foreign firms operating within their boundaries, with requirements to provide them greater rights than domestic firms,” Public Citizen’s analysis added. “The leaked text reveals a two-track legal system, with foreign firms empowered to skirt domestic courts and laws to directly sue TPP governments in foreign tribunals. There they can demand compensation for domestic financial, health, environmental, land use laws and other laws they claim undermine their new TPP privileges.”

The tribunals, which already exist under the framework established by prior trade deals during the Clinton and Bush administrations — like NAFTA and CAFTA — are also problematic, according to Public Citizen. Because their proceedings are conducted in private, no media may access their deliberations, and various international trade attorneys take turns filling the role of judges, who are selected by stakeholders.

In the event of a dispute between two entities incorporated in two different countries that are both members of one of these treaties, a trade tribunal serves essentially as a parallel legal system that exists outside of national laws and wields the power to knock down those laws or free multinational corporations from their obligation to comply with them. Considerations pertaining to labor rights or environmental protections are often not factored in to these decisions.

Although President Barack Obama had pledged during the 2008 presidential campaign to “not support NAFTA style trade agreements in the future,” he appears to have embraced them instead.

The TPP agreement has been in negotiations for years now, with major revisions being made during each successive round of talks, so it’s not clear if these proposals are set in stone just yet. Public Citizen noted that while nearly all of the TPP member states have agreed to these terms — including New Zealand, Singapore, Malaysia, Vietnam, Chile and Peru — Australia has not, which could hold up the continuing talks, set to resume this July in San Diego.

One of the reasons Australia appears hesitant is the country’s own experience with corporate trade tribunals organized through the World Trade Organization (WTO). British American Tobacco has admitted that it provided assistance to other big tobacco companies looking to use that system to fight forthcoming regulations that ban artwork on cigarette packaging. By incorporating in a country that has a trade agreement with Australia that’s similar to the TPP proposal, those tobacco companies gain access to the WTO’s trade tribunal process, which could ultimately overrule the country’s own laws.

But even if Australia’s reluctance does cause a problem for TPP negotiators, the press and public won’t likely find out about it, as U.S. trade talks are always conducted behind closed doors and usually with stakeholders from private industry present. With the TPP talks, that secrecy has been particularly contentious, and even some of President Barack Obama’s own allies in Congress have called upon him to force the U.S. Trade Representative to open the meetings to press and publish documents online.

Despite the push-back from members of his own party, President Obama has called the creation of “a seamless regional economy” in the Pacific-rim a “top priority” for his administration. “And we consider it a top priority because we’re not going to be able to put our folks back to work and grow our economy and expand opportunity unless the Asia-Pacific region is also successful,” he explained last November.

Public Citizen’s Lori Wallach explained in prepared text that the most startling details in TPP’s leaked “investment” chapter “may well be why U.S. trade officials have been so extremely secretive about these past two years of TPP negotiations.”

“Via closed-door negotiations, U.S. officials are rewriting swaths of U.S. law that have nothing to do with trade and in a move that will infuriate left and right alike have agreed to submit the U.S. government to the jurisdiction of foreign tribunals that can order unlimited payments of our tax dollars to foreign corporations that don’t want to comply with the same laws our domestic firms do,” she said.

The U.S. Trade Representative’s public affairs office did not respond to Raw Story’s request for comment.

Tuesday, June 12, 2012

"Flame" Malware Code Traced To Stuxnet, US Govt.

Researchers find a link between the two different pieces of malware, suggesting that the U.S. government may be behind both.
By Mathew J. Schwartz -- InformationWeek
Did the U.S. government commission the recently discovered Flame malware? According to new research, the developers of the Stuxnet and Flame malware families crossed paths--swapping source code at least once--which suggests that the U.S. government didn't just commission Stuxnet, but Flame as well. 

"In 2009, part of the code from the Flame platform was used in Stuxnet," said Alex Gostev, the chief malware researcher at Kaspersky Lab, Monday in a blog post. "We believe that source code was used, rather than complete binary modules," he said, which suggests some degree of collaboration or crossover.


But based on Kaspersky's ongoing teardowns of the Flame malware discovered in late May, he believes that "since 2010, the platforms have been developing independently from each other, although there has been interaction at least at the level of exploiting the same vulnerabilities."

According to published news reports, senior White House officials have said that the the United States led Stuxnet development, working with Israel. Hence if Stuxnet and Flame are related, it suggests that the United States is also behind the complex Flame malware.
 
That Stuxnet credit-taking--read by some as election-year boasting and by others as a direct warning to Iran--has led to charges that government officials mishandled classified information, although many security experts said all signs clearly pointed to the two governments having been behind Stuxnet and the related malware Duqu. Now add Flame to that equation.

But Gostev said there appear to have been different development groups behind the two malware families--each working independently since 2007 or 2008--which he refers to as "Team F" (for Flame) and "Team T" (for Tilded, which is the platform on which Stuxnet and Duqu were built).

"Flame and Tilded are completely different projects based on different architectures and each with their own distinct characteristics," he said. "For instance, Flame never uses system drivers, while Stuxnet and Duqu's main method of loading modules for execution is via a kernel driver."

According to Kaspersky Lab, Stuxnet appears to have been created in the first half of 2009, while Flame had been created by the summer of 2008. "The Stuxnet code of 2009 used a module built on the Flame platform, probably created specifically to operate as part of Stuxnet," said Gostev. That module, which he suspects exploited a then-unknown--a.k.a. zero-day--Windows kernel vulnerability later patched by Microsoft, was apparently removed in 2010. Its removal was likely prompted by Stuxnet's developers having created a new way to allow their malware to propagate, by exploiting a then-unknown Windows shell vulnerability, later patched by Microsoft.

While the two groups of malware developers appear to have shared code, "after 2009, the evolution of the Flame platform continued independently from Stuxnet," said Gostev.

Flame includes numerous attack capabilities, including the ability to spread via Windows Update by using a spoofed digital certificate. As a result, the malware can automatically install itself on targeted computers, providing another computer on the same network had first been compromised.

But Microsoft has been working quickly to patch the certificate bug exploited by Flame. Notably, Microsoft released an update Friday for Windows Server Update Services (WSUS) 3.0 Service Pack 2 (SP2), which according to the release notes "strengthens the WSUS communication channels ... [by] trusting only files that are issued by the Microsoft Update certification authority."

Microsoft is also set to issue an update Tuesday--as part of its monthly Patch Tuesday--that will further update all supported versions of Windows to block Flame. Security experts are recommending that all users install the update as soon as possible, since attackers will likely attempt to use the certificate vulnerability before it becomes widely patched. "Apply the certificate patch released a week ago today if you haven't done so already," said SANS Institute chief research officer Johannes B. Ullrich in a blog post. "This way, no patch signed by the bad certificate should be accepted tomorrow. Patch Tuesday is one of the best dates to launch such an attack, as you do expect patches anyway."

When installing the update, however, do so preferably only if using a trusted environment. "Avoid patches while 'on the road.' Apply them in your home [or] work network whenever possible," said Ullrich. "This doesn't eliminate the chance of a 'man in the middle' (MitM) attack, but it reduces the likelihood."

For users who must update while on the road, perhaps because they travel frequently, always use a VPN connection back to the corporate network, said Ullrich, since hotel networks can be malware and attack hotbeds. "Hotel networks and public hotspots frequently use badly configured HTTP proxies that can be compromised and many users expect bad SSL certificates--because of ongoing MitM attacks," he said.

Sunday, June 10, 2012

CDC: Teens now favor pot over cigarettes


Well, at least they'll live longer...-jef
 
 ++++
 
 
 
A study released Friday (PDF) by the Centers for Disease Control (CDC) found that in 2011, for the first time ever, more American teens were smoking marijuana than cigarettes.

The CDC’s annual Youth Risk Behavior Survey tracks drug abuse, among other potential destructive behaviors, by surveying high school students across the country. The agency said it collected data from more than 15,000 surveys taken in 43 states and 21 large urban school districts.

The result: Marijuana is officially more popular than cigarettes among U.S. teens, for the first time ever. A full 23 percent of students surveyed told the CDC they had used marijuana within the last month, whereas just 18 percent said they had smoked cigarettes.

The findings are consistent with a Raw Story analysis of the 2011 Partnership for a Drug-Free America report on teen drug abuse, which found that marijuana’s popularity has exploded since 2008. By comparing the Partnership’s data to prior CDC studies, Raw Story concluded that marijuana use had finally exceeded cigarette smoking among U.S. teens, which the CDC has now confirmed directly.

The Partnership’s report noted that almost half of American teens (47 percent) said they have used marijuana at least once, representing a 21 percent increase over their 2008 study. The CDC, on the other hand, noted in 2009 that 30 percent of high school students reported having experimented with cigarette smoking at least once, down from 39 percent in 2000, while about 24 percent had used a tobacco product (including chewing tobacco) recently, down from 34.5 percent.

There are several possible ways to contextualize the swing among American teens from cigarettes to marijuana, but one sticks out above all the rest: the economic recession.

Researchers at the University of New Hampshire reported in 2010 that they had debunked the “gateway drug” theory through scientific analysis of assorted risk factors that contribute to the desire to abuse more destructive drugs like heroin or prescription pills. Instead of early experiences with marijuana weighing significantly on that decision, researchers found that other stress factors like unemployment weigh much more in determining a teen’s likelihood to become addicted to harder, potentially lethal drugs.

“Employment in young adulthood can protect people by ‘closing’ the marijuana gateway, so over-criminalizing youth marijuana use might create more serious problems if it interferes with later employment opportunities,” one of the study’s authors said in a press release.

The U.S. Bureau of Labor Statistics reported in April that teen unemployement was hovering around 25 percent, down from 27 percent in 2009 — its highest rate since the Great Depression, and roughly 10 percent higher than the teen unemployment rate in the years leading up to the near economic collapse of 2008.

Added: Since no such regulatory framework exists for marijuana, and since drug dealers do not tend to check IDs, most youths told the National Center on Addiction and Substance Abuse in 2009 (PDF) that pot is easier to purchase than regulated substances.

The Campaign for Tobacco-Free Kids has consistently raised issue with “youth-penalty laws” (PDF) that punish kids for using tobacco, saying the laws are favored by tobacco companies because they oppose the truly effective means of control, like public education, restrictions on marketing and increased retail prices. By agreeing to penalize the end user, the Campaign claims that lawmakers ultimately just “divert the police from their efforts to stop retailers from illegally selling tobacco products to kids,” which results in breeding “disrespect for the law” among young people.

The Drug Policy Alliance, America’s leading drug policy reform group, says something startlingly similar about marijuana.

“It’s time to step back and ask ourselves what’s the best way to solve the problem we’re trying to solve—how to reduce drug abuse and addiction—and use the best available evidence to guide us,” Jag Davies, publications manager for The Drug Policy Alliance, said in a recent advisory. “And, ultimately, it’s time to bring marijuana out of the shadows and under the rule of law. The evidence shows that the most effective way to reduce teen marijuana use would be to regulate it in a manner similar to alcohol, with age limits, licensing controls, and other regulatory restrictions.”

Sima de los Huesos: The largest deposit of human fossils in history

The largest deposit of human fossils in history
by Ignacio Martínez, Ana Gracia & Juan Luis Arsuaga


Sierra de Atapuerca nevadaThe Sima de los Huesos is a small pit situated in one of the corners of the Cueva Mayor in the Sierra Atapuerca, a modest rise in the terrain located approximately 12 kilometers east of the city of Burgos. At 3,700 meters, the geological complex denominated Cueva Mayor-Cueva de Silo is one of the longest in the Duero River Basin and has two entrances. One of them, known as the Portalón, contains one of the largest Bronze Age sites in the northern Spanish Meseta. An enigmatic cave painting in red lines representing the shape of a horse’s head can be seen on one of its walls.

At the eastern edge of Portalón is the access to the Galería del Sílex, which contains a spectacular prehistoric sanctuary from the end of the Neolithic and the Bronze Age. This sanctuary was discovered intact at the end of the 1970’s by members of the Grupo de Espeleología Edelweiss (GEE), a cave exploration society from Burgos, after the opening of a passage closed by natural causes thousands of years ago. As we will see, the GEE has always played an outstanding role in the great discoveries made in the Sierra de Atapuerca.

Sala del Coro (Cueva Mayor, Atapuerca)On the western edge of the Portalón there is access to another corridor that, after a narrow passage, opens into a colossal cavern with a high ceiling, named the Sala del Coro. At the other extreme of this cavern, about 100 meters from Portalón, three main galleries cross one another and diverge in different directions: to the north, the Galería de las Estatuas, to the northwest the Galería Baja, and to the south the Galería del Silo. The Galería Baja crosses the Trinchera del Ferrocarril at the site called Sima del Elefante, which was one of the ancient entrances (now sealed) to the Cueva Mayor.

Following the Galería del Silo, and after passing through a set of very narrow, tight passageways, another huge gallery is reached, the Sala de los Cíclopes, located about 600 meters from the cave mouth at the Portalón. The excavations in this cavern have revealed that this was a place chosen by bears to hibernate. The bears belonged to a species that went extinct more than 120,000 years ago and their scientific name is 'Ursus deningeri'. Fossils of this bear species were found in the Sala de los Cíclopes, along with circular impressions in the clay floor (hibernation beds) which were left by the animals when they hibernated. In addition, on the still fresh clay walls there are traces of bear clawmarks and paw prints.

Paso de la Gatera en la Cueva MayorIn the southeast extreme of the Sala de los Cíclopes a steep ramp ascends to reach a small blind recess that houses a deep pit around four meters wide and thirteen meters deep. This is the Sima de los Huesos. At the base of this pit descends a clay ramp with a low ceiling around three meters wide by nearly ten meters long. This sector of the site is denominated SR (Sima-Rampa) and it ends in a small rectangular room, of around seven meters in length by three meters in width, denominated SH (Sima de los Huesos). This area, systematically excavated since 1984, contains the largest accumulation of human fossils ever discovered.

History of a Discovery

Although the Sierra de Atapuerca is internationally known for its Pleistocene sites, the earliest investigations were focused on more recent prehistoric periods. In 1910 Jesús Carballo published the first archaeological and paleontological discoveries of the Cueva Mayor, mentioning the existence of the horse’s head, painted in red, in the Portalón, which Henri Breuil classified as Franco-Cantabrian Paleolithic art. Other important researchers of the time, such as Hugo Obermaier, Emilio Alcalde del Río or Martínez Santa-Olalla, also studied this site.

Primera excavación en la Cueva Mayor (Atapuerca) en 1973, a cargo de J.M. ApellánizLater, in 1964 Francisco Jordá and Geoffrey Clark in 1971 carried out the first systematic excavations in the Portalón, documenting an important stratagraphic sequence. After opening a blocked access which had been closed for millenia, in 1972 the GEE discovered the Galería del Silex which dates from the Neolithic to the Bronze Age and preserves burial chambers, numerous examples of rock art, interesting ceramics, and evidence of flint extraction. All of this was preserved intact up to the present day. Between 1973 and 1983, José María Apellániz carried out new excavations in Portalón, investigating a much more extended surface area than before, and also coordinated the research carried out in the Galería del Sílex.

Coinciding with the excavations of Apellániz, in 1976, an unexpected event changed the orientation of the excavations in the Cueva Mayor forever. That year Trinidad Torres, an expert in bear evolution in the Iberian Peninsula, studied the Pleistocene levels of the Trinchera (in the sites Gran Dolina and Galeria) searching for mammal fossils, particularly bear remains. During his fieldwork, members of the GEE alerted Torres about the large quantity of bear fossils in Sima de los Huesos.

Pintada del S.XVI en la Cueva Mayor de AtapuercaIn fact, as graffiti on the cave walls attested, the area of Cueva Mayor where the Sima de los Huesos is located has been visited for centuries by people from neighboring villages. The Sima de los Huesos was a particularly attractive place because of its richness in bear remains, with the bear canines being the most coveted prize for the people that visited over the decades.

Encouraged by these reports, Torres organized a short excavation campaign with the GEE in the Sima de los Huesos that same year. Unexpectedly, a human jawbone was found among the numerous bear remains that were recovered. The connection between this human fossil and the bear fossils, which belong to a species extinct for over 120,000 years, suggested a considerable antiquity for the human mandible.

Realizing the significance of the finding, Torres took the human mandible to his thesis adviser, an expert in human evolution, Emiliano Aguirre, who recognized the presence of archaic features typical of European human populations of the Middle Pleistocene, highlighting its relevance. Later on, a more detailed inspection of the fossils acquired in the 1976 excavation, resulted in the recognition of more human fossils: some teeth, new fragments of jaw, skull, and long bones.

Mandíbula humana AT-1, el primer fósil humano identificado en la Sima de los Huesos en el año 1976Two years later in 1978, Aguirre started the new task of excavating the Pleistocene sites of the Sierra de Atapuerca, located in the Trinchera del Ferrocarril and in the Sima de los Huesos. To do so, he organized an interdisciplinary team, consisting of specialists in geology, archaeology, and paleontology, which started to work at the sites of the Trinchera del Ferrocarril. Although the Sima de los Huesos, where human fossils had been found, was the most attractive site, its particular conditions did not allow systematic excavation until 1984. However, in 1983 a small sample was collected from the site in which new human fossils were discovered.

El interior del yacimiento de la Sima de los Huesos en plena excavaciónSima de los Huesos has no comparison with any other site in the world. At no other site does one have to walk through a kilometer of winding subterranean passages, descend to the bottom of a deep pit and work in an extremely oxygen-poor atmosphere. In addition, the activities of the amateur spelunkers that have descended to the site over the years searching for coveted bear fossils have altered the superficial levels of sediments, breaking many bones and mixing them up with trash and limestone blocks in a uniform jumble. As a result, before starting to plan a systematic and rigorous excavation, it was necesary to evacuate tons of these altered sediments and limestone blocks from the site in order to access the intact levels.

In a short visit to the site in 1983, a few kilos of sediment were collected to test if there were still human fossils in Sima de los Huesos. The discovery of two human teeth while carefully cleaning and screening the obtained sediments confirmed the great scientific potential of the site. In light of these findings, systematic excavation of the site was begun during the next field season.

Los 14 metros de altura del pozo que conduce al yacimiento de la Sima de los Huesos, se descienden a través de una escala.In the 1984 field season, a new excavation strategy was determined and the basic infrastructure was installed to carry it out. The altered sediments were removed in backpacks, each one carried out of the Sima by members of the excavation team. The team then took the sediments to the edge of the neighboring Arlanzón River were they were washed on screens to recover the bone fragments. These fragments were later sifted to more carefully search for the human remains.

To work at the site, it was necessary to install an electric light in the Sima de los Huesos, since the use of gas lamps was already consuming much of the oxygen present at the site. To solve this, the team ran an electrical cable of almost a kilometer in length, from the Portalón to the Sima de los Huesos, where they installed a simple electrical setup consisting of a few sockets and lightbulbs. They also installed a hanging grid system, attached to the ceiling of the cave, in order to locate and map future fossil discoveries following proper archaeological protocols.

During the final days of the 1984 excavations, a small area of unaltered sediments was discovered at the western edge of the site, where the level of the disturbed sediments was very thin. In this zone (know as Area A), four human fossils were discovered, adding to the 78 specimens that were recovered while washing and screening the overlying disturbed sediments.

During the 1985 field season, Area A was systematically excavated, yielding three new human fossils. The level with human fossils, however, was very thin and was quickly exhausted. It was evident, then, that the main efforts had to be concentrated in the removal of the disturbed sediments which occupied most of the site, with the hope of finding the same level with human fossils discovered in Area A under the layer of altered sediments at other parts of the site.

This work, already begun in 1984, was carried out from 1985-1989, during which time more than 12 tons of limestone blocks and sediments were extracted from the Sima de los Huesos, without the use of any type of machinery, resulting in the discovery of 131 new human fossils.

In 1987, the team designed and installed a suspended platform at the site, anchored to the walls, which allowed work to proceed without stepping on the floor. In addition, a perforation was drilled from the outside through the ceiling of the neighboring Sala de los Cíclopes to facilitate the removal of sediments and improve the ventilation in the Sima de los Huesos.

Muchos de los fósiles que se han encontrado en la Sima de los Huesos han aparecido en el lavado de los sedimentosThis removal of altered sediments was completed during the 1989 field season. However, the most important discovery of that year was that the level of human fossils found in Area A in 1984, and apparently exhausted in 1985, extended across a larger area than was originally suspected. The last phase of the 1989 campaign and part of the 1990 field season was dedicated to the systematic excavation of this level, yielding 47 new human fossils.

The 1990 campaign marked a turning point in the excavations in the Sima de los Huesos. On one hand, the extension of the fertile level of human remains in the A area was delimited, and turned out to be quite small, giving the impression that the site was close to be exhausted. Secondly, the precise location was located within the cave of where the disturbed sediments were secondarily dumped after their removal from the Sima by the original team which excavated in 1976. These sediments were removed to the outside during the 1989 and 1991 campaigns. The cleaning and sifting of this material produced 161 new human remains. Finally, during the last days of the 1990 excavation six human remains in another area of the Sima were found next to the northern wall. This new excavation area was called Area B. The newly recovered human remains in Area B were the most complete and best preserved among all the discoveries to date.

Between 1984 and 1990 in the Sima de los Huesos, 389 human remains had been found. Of these, 335 came from sediments which had been disturbed by the amateur spelunkers, and 54 had been found among undisturbed sediments in Areas A and B. Although the number of fossils was impressive, being larger than all of the other sites of the Middle Pleistocene (780,000-120,000 years ago), most of the fossils were small fragments that apparently could not provide much information (as some of our colleagues liked to remind to us, a bit maliciously). Yet, this was a false impression. There were two fairly abundant skeletal elements in the Sima de los Huesos sample, which provided very relevant information.

Los dientes, gracias a su resistencia y al gran número de piezas por individuo, son un fósil muy abundantes en Sima de los Huesos. Representan al menos a 28 individuosOn the one hand were the teeth, that helped establish the presence of at least 20 individuals (or dentitions) within the sample. This was a very large number at any site containing human remains, regardless of the location or chronology. Human remains are among the rarest of paleontological discoveries, making them very valuable. Only a small fraction of archaeological sites have yielded human remains, and one can count with one hand the number of sites with the same antiquity of the Sima de los Huesos where the minimum number of individuals found exceeds half a dozen. The significance is not simply to break a record (“my site has more individuals than yours”), but rather takes on a singular scientific importance. If the number of individuals in a sample is very small, it is not possible to know the variability of the original population, and therefore it is very difficult to evaluate the research results. On the contrary, when the number of individuals is large, it is possible to determine the causes and degree of biological variability and arrive at firm conclusions about the human remains. In this context, one can understand the significance of the large number of individuals preserved at the Sima.

However, on the other hand, it is not very useful to have identified many individuals by their teeth if there is not much left of their skeletons. At this point, the other abundant skeletal elements in the sample from the Sima de los Huesos gains significance, most notably the phalanges of the hands and feet. These small bones are among the most fragile and delicate in the human skeleton, and they are exceptional in sites as old as the Sima de los Huesos. In fact, among all the archaeological sites of the Middle Pleistocene, just a single human phalanx has been found, from the site of Zhoukoudian in China (the well known “Pekín Man” site). Over the years, more than 60 phalanges were recovered from the Sima de los Huesos, an amazing number. This suggested to the members of the excavation team that if these fragile bones were found at the site, it was logical to believe that other parts of the skeleton would also be preserved.

Todas las regiones del esqueleto están reperesentadas en la Sima de los Huesos. Si las juntasemos podriamos tener un esqueleto compuesto como el de la imagen, si bien muy probablemente no represente un único individuoThe 1991 field season began under a new scientific leadership. Until 1990, the year in which he retired, Emiliano Aguirre was the director of the excavations at the diverse Pleistocene sites of the Sierra de Atapuerca. During those years, the excavation team had been organized around three outstanding collaborators of Aguirre: Juan Luis Arsuaga, José María Bermúdez de Castro and Eudald Carbonell. This situation led the team to aquire a different and relatively original structure, with a collaborative leadership under the direction of the three leaders of the different teams. Following this reorganization, Arsuaga, who had been in charge of the excavation in the Sima de los Huesos under Aguirre’s management, continued this work.

In the 1991 campaign, the team completed the excavation of the dumped deposits from the original 1976 excavation (adding 54 new human remains), and the systematic excavation of Area B was undertaken, where as mentioned previously, six very complete human fossils had been found in 1990. Soon after, it was realized that the level where those fossils were found had not been altered by the amateur spelunkers, which made the team hopeful about finding new complete and well preserved human remains in Area B. The expectations were entirely justified since by the end of the campaign, in a surface area of just an eighth of a square meter (1/8 m2) excavated to a depth of only 20 cm, they had recovered 112 new human fossils. However, the most important fact was not the number of fossils found in an intact geological level, but the extraordinary state of preservation of the fossils. In addition, bones from parts of the skeleton were found that had never before been recovered (or were extremely rare) at any other site of the same time period. The Sima de los Huesos started to become recognized as an exceptional site, for both the number of fossils and their scientific significance.

Excavación del Cráneo número 4 (Agamenón) en el año 1992But this new situation also presented new working conditions and new challenges. The fossils coming from the intact sediments were much more fragile than the ones from the distrubed sediments, which made their excavation a much more delicate task. A hardening solution was needed to extract the skeletal remains from the sediments without them deteriorating. Given the very high relative humidity in the air at the Sima de los Huesos, it was not possible to use the most common hardening solution, which is dissolved in water, and it was necessary to make new ones dissolved instead in acetone. On the other hand, to excavate in the intact levels a different, more systematic methodology is necessary compared to working with disturbed sediments. In essence, the objective is to register as accurately as possible the three-dimensional position of each fossil before it is removed. This method is commonplace in any archaeological excavation.

But there is no single excavation in the world comparable to the Sima de los Huesos. At no other site do they recover hundreds of human fossils each field season. Thus, it was decided to modify the traditional archaeological method in an important detail. While the excavation maps at most other sites are made at a 1:10 scale, in the Sima de los Huesos they are drawn at a 1:1 scale. This change of scale implies a relative increase in the prescision of the maps, given that 1:1 scale is ten times more exact than that of 1:10. But this increase of precision also significantly increased the work necesary to make the maps at this new scale.

Una vez excavados, los fósiles de la Sima de lo Huesos son mapados. De este modo, podemos conocer la posición exacta en la que se encontraban los restos antes de su extracciónIn addition to modifing the field methods during the excavation, it was also necessary to change the work plan in the laboratory. There were now many more fossils to clean, preserve, and catalog, all without losing the exact place of origin of each fossil. To this end, all the excavation and laboratory methods were reconsidered and new protocols were established to optimize the labor within the reduced time during the field season.

The excavation of 1992 was planned with an extremely ambitious objective. On the one hand, the systematic excavation of the dense levels of human fossils in Area B was continued, and at the same time, excavation in more limited and selected (test) areas along the access ramp to the site (designated Sima-Rampa, or SR) were initiated. The excavation in these test points (named SRB, SRM, SRA) contributed very valuble information in understanding the stratigraphy and formation of the site. In addition, 16 human fossils were recovered in SRB and SRM, some of which could be joined to other fragments in sediments from SH, making it clear that the human remains were originally deposited on the ramp.

Although these finds were important, the most incredible discoveries during this year came from Area B – finds that would catapult the Sima de los Huesos Site, and in turn the Sierra de Atapuerca, to the forefront of the scientfic world.

Un momento histórico: despues de trabajar durante toda la campaña de 1992 en su extracción, el Dr. Martínez entrega al Profesor Arsuaga el Cráneo 4 de la Sima de los HuesosIn the first fews days of excavation a complete neurocranium was discovered (Cranium 4), informally baptized “Agamemnon,” in homage to classical archaeology. To demonstrate the importance of this find, it is sufficient to point out that there is only a single skull of comparable antiquity in the whole archaeological record of Europe. The task of excavating this fossil occupied almost the entirety of the field season and occupied an area of around one quarter square meters (1/4 m2), to a depth of some 25cm. In this same area, an additional 200 human fossils were subsequently excavated, including a second human skull (Cranium 5), named Miguelón in honor of the 5-time champeon of the Tour de France, Miguel Indurain. In contrast to Agamemnon, Miguelon also preserved the facial bones and, to this day, is the best preserved and most complete fossil human skull ever discovered. In addition, several skull fragments found this year, together with others recovered during previous field seasons, allowed the reconstruction of a third very complete skull belonging to an individual who died at around 13 years of age and named "Rui", in honor of the legendary figure from Burgos, Rodrigo Diaz de Vivar.

El Cráneo 5 de la Sima de los Huesos, aparecido en el año 1992The 1992 finds proved to be an important turning point in the international recognition of the site, which now began to be considered one of the most important sites for human fossils in the world, and key to the understanding of human evolution in Europe during the Middle Pleistocene.

Since then, the excavations have continued uninterrupted in the Sima de los Huesos, summer after summer. Over the years, the site has continued to produce incredible finds. In 1994, the same year that the first fossils of 'Homo antecessor' were found in level TD6 of the Gran Dolina, the only practially complete and undeformed human pelvis (Pelvis 1) in the fossil record was recovered from the Sima. Following the tradition of giving informal names to exceptional fossils, it was coined Elvis, in memory of the pelvic gyrations of the King of Rock and Roll, Elvis Presley. In the last 14 years we have encountered thousands of human fosils at the Sima de los Huesos, up to a provisional total of 5,500. This is an extraordinary number, that excedes the total number of human fossils found the rest of the sites on the planet.

La Pelvis 1 ('Elvis') de la Sima de los Huesos (Burgos, Atapuerca). Es la más completa del registro fósil mundial y pertenece a un individuo masculino de la especie 'H. heidelbergensis'Above all, the most intriguing find, and perhaps the most far-reaching of all in the Sima de los Huesos, has not been a human fossil. In 1998, in the same level as the human fossils, the only stone tool ever found at the site was recovered: a stone handaxe (or biface), made of red quartzite, which we named Excalibur.

The type of flaking corresponds to Mode 2, or Acheulean, technology, which coincides with the human type (see below) found in the Sima de los Huesos. This type of technology is widely found in other sites of Atapuerca, in the Trinchera de Ferrocarril, of a similar geological age, such as Galeria and the upper levels of Gran Dolina. It’s interesting to point out that at these sites, similar-sized tools made of the same raw material as the handaxe at the Sima de los Huesos are rare.

All these discoveries, Elvis, Excalibur and most of the thousands of new fossils came from Area B in SH, where excavation is far from being completed. The new field seasons (2002-2005) have been carried out pursuing a new scientific strategy. Instead of continuing work in Area B, whose richness in human remains is well established, major efforts have been focused on the SR and other locations, different from Area B, in SH. The aim is to enhance the data on other relevant aspects of the site: to confirm the proposed stratigraphy, to refine the dating of the site and to determine the geometry of the deposit.

La única pieza de industría lítica encontrada en la Sima de los Huesos: un bifaz realizado en cuarcíta roja y apodado ExcaliburAs the result of these activities, several dozen new human remains have been found in the highest area of SR (in a location called SRA), which undoubtedly belong to the same individuals that were found in SH, confirming the results of prior campaigns in the original place of deposition of the skeletons. In addition, in this spot (SRA) it has been possible to date the fossil deposit with absolute accuracy at more than 350,000 years old. Later we will discussin detail the question of dating the fossils from the Sima de los Huesos. However, we will first devote some lines to a question that inspires curiosity in the general public: How much is still left to excavate in the Sima de los Huesos?

This is a question without a definitive answer given the nature of the site. In fact, many years of work were necessary to begin to understand the geological complexity from the data recovered during many field seasons.

Entre los fósiles humanos de la Sima de los Huesos aparecen mexclados los restos de al menos 167 osos, pertenecientes a la especie 'Ursus deningeri', un antepasado del oso de las cavernasThe human remains appear, together with bear remains (the Ursus deningeri" species), in a red clay stratum. This sedimentary level was deposited on an irregular relief already present, resulting from prior periods of sediment erosion and deposition. This level of red clay rich in human remains was in turn altered by subsequent water circulation at the site, resulting in a new irregular relief. Later on, another level containing fossils of the same bear species and of other carnivores (see below) covered the sediments rich in human remains. In this way, different levels do not have a constant thickness throughout the site, nor are they horizontally located one above the other, but make contact laterally.

To this irregular geometry of the deposit, a consequence its complex geological history, it must be added that the human remains are not homogeneously distributed in their corresponding red clay level. On the contrary, they have accumulated in some parts of the SH, such as Areas A and B, while in other areas of the site there are hardly any fossils. This chaotic distribution is the result of the bones which reached the SH being carried there by small mud slides from their original place of deposition in the ramp (SR).

Una vez que los fósiles son recuperados del yacimiento y lavados, se extienden hasta que se secan por completoAs a result, it is not possible to predict exactly how long it will take to complete the excavation of the site. However, there is one very interesting piece of information. The team working at SH has estimated the percentage of human remains which have been recovered in relation to the total initially accumulated in the site. This calculation is based on the certainty that in the Sima de los Huesos there has been an accumulation of complete skeletons of at least 28 individuals. This information, along with other studies on the pattern of fracturing of human remains at the site, allows a prudent estimate of the number of human remains expected in the site. The team believes that to date just a third of the existing human remains at the site have been recovered.

Dating a Site

One of the most fascinating questions for the general public in the field of paleontology is the age of the fossils. It seems amazing that it is possible to know the date of such remote events that no one witnessed with such precision. Although a detailed explanation of the different techniques that scientists use to date fossils is beyond the scope of these pages, we explain some general considerations that are useful to understand the basics of the methods and evaluate the results.

In paleontology there are two ways of dating an event. One is to establish a relative date, that is, to situate an event within a temporal order of events. For this procedure, the antiquity of the object is established in terms of “before, or after,” but does not imply knowledge of the exact date. This concept can be illustrated with an example from daily life. The terms, grandmother, mother, and daughter establish a relative date between three women - the grandmother the oldest, the mother in the middle, and the daughter being the youngest – but we don’t know the exact age of the women. Establishing the exact (or reasonably precise) age of the events is the objective of absolute dating.

Los materiales y métodos de excavación son el punto de partida para el trabajo de gabinete y la posterior publicación de los resultadosIt is a common mistake to think of the word “absolute”, when refering to a date, as indicating “definitive” or “incontestable.” In paleontology, definitive or incontestable dates do not exist, since they are always subject to contrast with the results of other techniques. Only when the dates obtained by various methods (relative or absolute) agree can they be thought to reasonably estimate (although constantly improved by new techniques) the date of a fossil or site.

Establishing the relative date of sites (and, thus the fossils contained in them) is a task done through the use of biostratigraphy. Essentially, this attempts to construct a chronological framework (or chronobiostratigraphic scale) that temporally organizes the distinct species that have lived throughout the history of biological life. To do this scientists employ concepts and methods from the field of geology (such as the law of stratigraphic superposition) and biology (like the irreversible nature of the evolutionary process). In this way, the different fosilized species that appear in a site indicate to a biostratigrapher the temporal period to which they correspond.

For their part, the techniques commonly used to obtain absolute dates are based on natural radioactive phenomona to establish how much time has passed since the occurence of a certain event. The relative porportions of certain isotopos (which give their name to each technique) are measured, since these proportions change as a direct function of the amount of time passed. If the event dated is the death of the organism that produced the fossil (as in the case of the well-known Carbon 14 technique), the antiquity of the fossil can be directly established. More commonly, the event to be dated by these methods is the formation of certain types of rocks, such as volcanic basalt (Potassium/Argon technique) or flowstones, stalactites and stagmites (Uranium-series technique).

Gracias al mapado de los fósiles en la Sima de los Hueso, podemos dónde y en qué posición se encontraba cada fósil en el yacimientoThere is one very important question when attempting to understand and analyze dates obtained by these methods: the maximum reach, limit or range of the method. This is the maximum age that can be reached, with acceptable precision, with each given technique. Currently, the limit of the method of the Carbon 14 technique is around 40,000 years. Beyond this date, the results of the technique are not reliable and it is not used to date events that are older than this. Essentially, the maximum effectiveness of each technique has is limited by its capacity to precisely measure the exact number of atoms of the corresponding isotopes. Inevitably, all measurement instruments have a margin of error, and the magnitude of this error determines the realiability of the results based on a determined date, which varies with each method. When a technological advance is produced that reduces the error and changes the precision of the measurement, then the maximum age limit is increased. This happened, for instance, when the reach of Carbon 14 increased by employing particle accelerators in association with the measuring instruments.

After this brief foray into the world of dating techniques, let’s return to the case of the Sima de los Huesos. As mentioned previously, when the first human mandible was discovered at the site in 1976, its association with Ursus deningeri bear fossils suggested a great antiquity. Since this species of bear went extinct around 120,000 ago, this appeared to be the minimum age attributable to the human fossil. However, the fact that the levels of the deposits from which both the bear and human fossils derived may have been disturbed by amateur spelunkers called this date into question. Some researchers have suggested that the bear fossils could hve come from a different stratigraphic level than that of the humans and, for this reason, they have different dates.

This doubt was not put to rest until the 1991 excavation when, once the disturbed sediments were cleared away, the intact levels were exposed and confirmed that they contained both 'Ursus deningeri' and human fosils. As such, the association between both species was confirmed and established a minimum age of 120,000 years for the site. While this highly significant date confirmed the great antiquity of the human fossils, it was still much too imprecise. At that time, no datable rock had been found at the site that showed a clear stratigraphic relationship with the human fossils, which led to two independent lines into the question. On the one hand, the rest of the faunal remains from the site were studied. At the same time, new experimental techniques were applied to date the fossils. The results of both methods coincided with an older minimum age for the Sima de los Huesos fossils of around 250,000 years ago.


El Cráneo número 5 apareció fragmentado en distintas piezas, una de ellas fue el hueso frontal de la imagenFinally, after more than 10 years of excavation in different areas at the site, during the 2001 field season a discovery was made that allowed for a more precise date. That year a horizontal stalagmite was found in the upper portion of the ramp (in the place designated SRA) that was deposited directly over the fossil-bearing levels which contained dozens of fossils of the same individuals found in SH. This type of sedimentary rock can be reliably dated by the uranium-series dating technique mentioned above. The results obtained from the stalagmite at SRA showed its age exceeds the maximum reach of that technique, established at 350,000 years, and as a result the human fossils are older than this date.

There is one final consideration to conclude this section on the antiquity of Sima de los Huesos. It is a common mistake to confuse the minimum age of a site with its absolute date. A minimum date of 350,000 years does not mean, as it is often mistaken in the media, that the site is exactly 350,000 years old, but rather that it is older than this date (without knowing how much older). This is an important point to make clear since we are sometimes approached by people who claim that we continue to change the date of the site over the years, making it older each time. This is not correct. What has happened is that the minimum age has been refined from 120,000 years ago in the beginning to 350,000 years ago currently. When technological advances lead to improvements in the measuring devices, thereby lowering their error, the date of the stalagmite of SRA will become even more precise and establish another adjusted minimum age for the site, which will inevitably be even older.


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Scientists accused of distorting theory of human evolution by misdating bones
By Robin McKie, The Observer
Saturday, June 9, 2012

 
Homo_heidelbergensis-Cranium_ via Wikimedia

 
Briton says Spanish researchers are out by 200,000 years and have even got the wrong species

It is the world’s biggest haul of human fossils and the most important palaeontology site in Europe: a subterranean chamber at the bottom of a 50ft shaft in the deepest recesses of the Atapuerca cavern in northern Spain. Dozens of ancient skeletons have been unearthed.
La Sima de los Huesos – the Pit of Bones – has been designated a Unesco world heritage site because of its importance to understanding evolution, and millions of euros, donated by the EU, have been spent constructing a museum of human antiquity in nearby Burgos.

But Britain’s leading expert on human evolution, Professor Chris Stringer, of the Natural History Museum, has warned in the journal Evolutionary Anthropology that the team in charge of La Sima has got the ages of its fossils wrong by 200,000 years and has incorrectly identified the species of ancient humans found there.

Far from being a 600,000-year-old lair of a species called Homo heidelbergensis, he believes the pit is filled with Neanderthal remains that are no more than 400,000 years old. The difference in interpretation has crucial implications for understanding human evolution.

“The Atapuerca finds are hugely important,” said Stringer. “There is no other site like it in terms of numbers of bones and skulls of our ancient predecessors. It is the world’s biggest collection of ancient human fossils and the team there has done a magnificent job in excavating the site. However, if we cannot correctly fix the age and identity of the remains then we are in trouble. Getting that wrong even affects how we construct our own evolution.”

La Sima de los Huesos was discovered by potholers exploring Atapuerca’s cavern system. One brought back a few fragments of human bone. Excavations led by Juan Luis Arsuaga, of Madrid university, began in 1990 and within two years had uncovered two complete human brain cases. Ribcages, leg bones and jawbones were also dug up. Arsuaga tentatively dated the finds as being 300,000 years old.

Since then, the remains of 28 bodies have been dug up, the world’s greatest single haul of ancient human fossils. During this time, Arsuaga and his team pushed back the dates of their finds to 600,000 years ago and assigned them as belonging to Homo heidelbergensis.
This dating and identification has caused increasing upset among other palaeontologists. The scientists at La Sima believe H heidelbergensis is an ancestor of Neanderthals but not of Homo sapiens. However, others, including Stringer, believe it is indeed an ancestor of our species.

“The problem is that many of the skeletons unearthed at La Sima clearly have Neanderthal features,” said Stringer. “In particular, their teeth and jaws are shaped very like those of Neanderthals. But all other evidence indicated Neanderthals did not appear on the scene for another 200,000 years. Dating these bones to such an early date completely distorts our picture of our evolution.”

This criticism is supported by Phillip Endicott of the Musée de l’Homme, Paris. His studies of human and Neanderthal DNA have shown the latter did not appear as a separate species until 400,000 years ago. “Yet the bones in La Sima, which bear Neanderthal features, are supposed to be 600,000 years old,” he said. “This cannot be true.”

Another criticism is of the method used to date the Pit of Bones. A stalagmite found just above the remains has been dated as 600,000 years old, using natural uranium isotopes, and Sima scientists argue that the fossils must be older. They say the 28 bodies were thrown into the pit as an act of reverence for the dead and that the stalagmite grew over the sediment containing the bones.

However, this interpretation is controversial. No one has found any other evidence of ceremonial behaviour in humans of that antiquity. In addition, there is a deficit of small finger and toe bones. “If complete bodies were thrown in there, you would expect to see every piece of human anatomy down there,” said Stringer. “But you don’t. A lot of skeletal parts seem to be missing.”

Yolanda Fernández-Jalvo and Peter Andrews, of, respectively, the Natural History Museums of Madrid and London, suggest the absence of small bones is best explained by assuming the bodies came from the cave system and were washed there by flood. Fingers and toes would have been lost as skeletons were swept into the pit where the stalagmite could already have formed.

However, Arsuaga has rejected this analysis. “You can call [the fossils] early Neanderthals or give them another name, it does not matter. I prefer to give a different name.” But he admitted the 600,000-year age his team had put on the Sima fossils did look too early. “We are working on that,” he said.