A 120,000 Year Old Neandertal from Krapina who had Fibrous Dysplasia

Tags

, , , , , , , , , ,

The internets are buzzing about the news of the earliest known bone tumor on record, predating others by more than 100,000 years. The tumor has been found on the left rib of a 120,000 year old Neandertal from Krapina, Croatia. The original paper is published under the title, “Fibrous Dysplasia in a 120,000+ Year Old Neandertal from Krapina, Croatia” in the journal PLoS ONE.

In the world of pathology, there are many terms to describe growth such as metaplasia, hypertrophy, neoplasia, hyperplasia and dysplasia. Dysplasia defines abnormal growth where cell differentiation is delayed. If a cell is committed to of one of the three germ lines, say ectodermal, a dysplastic cell of that lineage would then remain a ectodermal precursor and not differentiate into the nervous tissue or skin appendage it was programmed to become.

Bone is composed of two types of tissue, compact and trabecular. Compact bone is the dense, outside structure while trabecular or spongy bone is the fibrous layer that you often do not see. Fibrous dysplasia, therefore refers to the abnormal maturation of trabecular bone. Fibrous dysplasia is a benign, non-hereditary process. It was first described in the 1942 by Lichtenstein and Jaffe. The disease process may be localized to a single bone (monostotic) or multiple bones (polyostotic). Up to 80% of cases are monostotic.

Polyostotic fibrous dysplasia can occur as a part of McCune-Albright syndrome. McCune-Albright Syndrome often affects unilateral bones with ipsilateral café-au-lait spots on the skin, and endocrine disturbances such as precocious puberty. Fibrous dysplasia has also been reported in association with other endocrine dysfunctions such as hyperthyroidism, hyperparathyroidism, acromegaly, diabetes mellitus, and Cushing syndrome as well as an associated abnormality in Neurofibromatosis type II. Malignant transformation of fibrous dysplasia is very infrequent, with reported prevalences ranging from 0.4% to 4%.

We know that fibrous dysplasia is caused by a somatic mutation in the GNAS1 gene on chromosome 20q13.2-13.3. GNAS1 encodes the alpha subunit of the stimulatory G protein, Gsα. As a consequence of this mutation, there is a substitution of amino acid arginine in position 201 of the genomic DNA in the osteoblastic cells, by amino acid cysteine (R201C) or histidine (R201H). The abnormal G1 protein stimulates cAMP. Furthermore, proto-oncogene levels of C-fos and periostin are raised in fibrous dysplasia. Consequently, the osteoblasts expressing this mutation have a higher rate of DNA synthesis, leading to the formation of a disorganized fibrotic bone matrix with primitive bone formation, and lack of maturation to lamellar bone.

Figure 1. Krapina 120.71 in a caudal view (a). The large lesion is located above the tubercular facet and extends laterally. The trabeculae have been destroyed and the cortex appears expansive. The thin cortical bone forming the superior surface of the cavern was broken away postmortem. (b) Krapina 120.6 shows the normal pattern of bony trabeculae in the medullary space. The surface irregularities are post-mortem. doi:10.1371/journal.pone.0064539.g001

Figure 1. Krapina 120.71 in a caudal view (a).
The large lesion is located above the tubercular facet and extends laterally. The trabeculae have been destroyed and the cortex appears expansive. The thin cortical bone forming the superior surface of the cavern was broken away postmortem. (b) Krapina 120.6 shows the normal pattern of bony trabeculae in the medullary space. The surface irregularities are post-mortem.
doi:10.1371/journal.pone.0064539.g001

The specimen is Krapina 120.71, a 3 cm long, left rib fragment containing about 2/3rds of the neck, most of the tubercular facet and a small section of the shaft. It is thought to be rib 3-6. It was first unearthed between 1899 and 1905 in a cave known as the Krapina rock shelter in Croatia. This site held more than 900 Neandertal bones dating back 120,000 to 130,000 years ago. Many of the bones display signs of trauma, and a few show post-mortem cutting marks, perhaps indicating cannibalism or some sort of ritual reburial.

In the 1980s, University of Pennsylvania researchers X-rayed the entire collection. They published a book in 1999 showing each radiograph. Most of those X-rays were quite high-quality, but one exception was found in a little rib fragment which appeared “burned out.” That prompted the authors to return to the specimen. They adequately describe an osteolytic abnormality and offer differentials of chondroma, post-traumatic lesion and chronic osteomyelitis, but remain confident with their radiographic diagnosis of fibrous dysplasia via microCT scanning.

Bone lesions in the fossil and archaeological record are extremely rare for several reasons. Without adjacent soft tissue, it is hard to compare normal to abnormal. Furthermore, the decomposition process alters bone dramatically. Previously, the oldest known tumors came from Egyptian mummies and dated back only 4,000 years or so and a 1,600-year-old tumor containing teeth was found in the pelvis of an ancient Roman corpse. So to find a 120,000 year old Neandertal with a osteolytic lesion in the rib is significant.

What I find wrong with this publication is the spin; too often in our world of paleoanthropology do I see issue with people trying to put a particular bend to sell their otherwise interesting story as a sensational headliner. The press is running quotes from the senior author like,

“… indicates that Neanderthals were susceptible to the same types of tumors modern-day humans get, despite living in a remarkably different environment.

‘They didn’t have pesticides, but they probably were sleeping in caves with burning fires,’ says David Frayer, an anthropologist at the University of Kansas and the co-author…”

The problem with the above quotes stem from the conclusion,

“Finally, it is recognized that environmental changes wrought by humans, compounded by population expansion, have resulted in an increase the types and the intensification of the pollutants within the environment, many of which are directly associated with neoplastic disease and were not part of environments in the past [35]. Given these factors, most argue that cases of neoplastic bone disease are rare in prehistoric human populations [27]–[28]. It is against this background that the identification of a 120,000+ year old Neandertal with a primary osteolytic lesion is surprising and one that provides insights into the nature and history of the association of humans to neoplastic disease.”

Putting an emphasis that Neandertals lived in “cleaner” environments and still had susceptibility to the same types tumors is extremely short-sighted. There are most definitely some tumors with strong associations to environmental mutagens, such as tobacco consumption with mouth, throat and lung cancer or asbestos with mesotheliomas… To which I’d venture a hefty bet that Neandertals were not suffering from as much as modern humans are. So to use words like same types of tumors, or phrases like, “lived their lives basically the same way we did and basically with the same problems that we have,” is a stretch.

As explained earlier, fibrous dysplasia is caused a somatic mutation of the GNAS1 gene. Somatic mutations are acquired before birth, in utero, early in fetal development where DNA replication occurs at a rapid rate and errors can be made all throughout. The authors fundamentally neglect a discussion that most mutations are inherent problems in DNA replication, repair, tautomerism, depurination, deamination, and slipped strand mispairing.  A one-sided discussion that one benign bone lesion in one individual is indicative that prehistoric humans contracted the same cancers we do, despite environment, and had the same problems we have is incomplete.

Can we agree to just focus on the science and not extrapolate a faulted connection?

CITATION

Monge, J., Kricun, M., Radovčić, J., Radovčić, D., Mann, A., & Frayer, D. (2013). Fibrous Dysplasia in a 120,000+ Year Old Neandertal from Krapina, Croatia PLoS ONE, 8 (6) DOI: 10.1371/journal.pone.0064539

About these ads

The BH-1 Hominin from Balanica (Serbia)

Last week, PLoS One published a paper re-dating the BH-1 specimen from Balanica. The new dates are 397 and 525 ka. The new dates are at least 280,000 years older than the previously published study. At this time, Neandertal traits were distinct in Europe.

BH-1 Hominin Mandible Fragment

BH-1 Hominin Mandible Fragment

But the mandible fragment features a primitive prominent planum alveolare, and a thick mandibular corpus. The exomolar sulcus is wide. A flat rather than concave sublingual fossa is present. And there is poor definition of the submandibular fossa. Given the size of the mandibular body, and that the dentition is relatively small; there is a complete lack of derived Neandertal features. Ultimately, this specimen fits well with Middle Pleistocene European archaic Homo specimens like Kocabaş, Vasogliano and Ceprano.

With the dates pushed back via electron spin resonance combined with uranium series isotopic analysis and infrared/post-infrared luminescence dating, the authors aim to further their claim that this niche area of the Balkans offered refuge. Unlike their counterparts, these humans in southeastern Europe were never geographically segregated from Asia and Africa by the glaciations that isolated and ultimately speciated other European humans.

Rink, W., Mercier, N., Mihailović, D., Morley, M., Thompson, J., & Roksandic, M. (2013). New Radiometric Ages for the BH-1 Hominin from Balanica (Serbia): Implications for Understanding the Role of the Balkans in Middle Pleistocene Human Evolution PLoS ONE, 8 (2) DOI: 10.1371/journal.pone.0054608

Anthropologists Are Lowest Paid & Least Respected Scientists In the United States

Ann Gibbons has a piece in today’s Science where she writes of the troubles the field faces,

“In the fall of 2011, Florida Governor Rick Scott proclaimed that his state didn’t need any more anthropologists, and that public money would be better spent educating scientists. Then in January, a study found that the unemployment rate among recent graduates with bachelor’s degrees in anthropology and archaeology was 10.5%, surpassed by few other majors, and that anthropology majors who did get jobs were also among the lowest paid. It’s been a tough year for anthropology, but don’t count out this field: Most said the bad press wasn’t fair, noting that the situation is very different for bachelor’s degree– and advanced degree–holders.”

I do not have access to the full text, unfortunately. I can tell, though, that the study cited in the abstract only focuses on undergraduates. So there is a bias in her report, just as she writes in the last sentence. Without a doubt, those with graduate degrees have better opportunities.

What I do understand from my experience is that I was offered outrageously low salaries upon graduating with my Bachelor’s in Anthropology. My life was unsustainable. For that reason, I focused my Master’s in Biology, as my prospects in that field offered more financial stability.

Furthermore, anthropology is also plagued by misunderstandings. Scientists and non-scientists often do not know what anthropology is and what the can be gained from this field. I believe this is one of the reasons why the field is not adequately compensated.

I will leave this thread open for discussion by you, the readers, on what you think can be done to increase the financial return and improving the perception of the field.

Gibbons, A. (2012). An Annus Horribilis for Anthropology? Science, 338 (6114), 1520-1520 DOI: 10.1126/science.338.6114.1520

There’s Always Next Year…

Tags

, , ,

Thanks to the Maya Long Count calendar, the year 2012 has become something of a pop culture phenomenon.  You’ve probably seen plenty of TV, movie, and internet references to the upcoming “end of the world” on December 21st or December 23rd (it depends).  It’s a real bummer because the hope of “next year” is the only thing that has sustained me as a lifelong Seattle sports fan; once the Mariners win a World Series, then the world can end!

But, seriously, Maya scholars are not worried about 2012 being Earth’s last year.  I’m neither a Maya scholar nor Maya descendant, so most of what I know about Maya calculations of time comes from popular sources like books, magazines, and documentaries.  In other words, despite being an anthropologist, I make no claims of being a Maya expert.

Here’s what I’ve learned: The Ancient Maya constructed elaborate calendars to mark the passage of time – everything from the length of a human pregnancy to the age of the universe.  Time was extremely important in Maya daily life and cosmology (the November/December issue of Archaeology Magazine – and final issue if the world does end this year – has a great summary of Maya calendars).  The Long Count calendar counts the number of days since the mythological date of Maya creation, and includes 1,872,000-day cycles called bak’tuns.  There are few known glyphs covering the 13th (current) bak’tun, but it is calculated to end on December 21st (or 23rd), 2012.

Obviously, most of us aren’t fearful about units of time coming to an end.  For example, seasons, decades, and centuries all end and new ones begin, usually without mass hysteria (Y2K was one recent exception).  It’s important to remember that the Long Count calendar marks the passage of time from a mythological date of creation.  This date is ritually significant, but we now know that time didn’t actually begin on August 11, 3114 BC (Maya date), October 23, 4004 BC (Ussher date), or any other date based on religious speculation.  Therefore, as Stephen Jay Gould wrote about Millennium panic in the year 2000, 2012 is an observance of a “precisely arbitrary countdown.”  Most of the end-of-the-world stuff comes from outside of the Maya world.  A recent AP article noted: “Such apocalyptic visions have been common for more than 1,000 years in Western, Christian thinking, and are not native to Maya thought.”

Modern Maya are excited about this year’s potential to spur interest in ancient Mesoamerica and archaeological tourism.  Guatemala has a great Bak’tun Route ad campaign which focuses on 2012 as a beginning, not an end.  Modern Guatemalan Maya communities still have “Daykeepers” who keep track of time: “’The world is going to die on December 23rd,’ says Christenson [Brigham Young University anthropologist], explaining that the Maya believe the world dies each day when the sun sets, or when crops are harvested.  ‘The world is constantly dying,’ he says, ‘and the role of the Daykeeper is to make sure they get things going again.’”

So, despite the end of the 13th bak’tun, I still have time to learn more about ancient Mesoamerica and, hopefully, enough time to see my Mariners win a World Series.  There’s always next year…

- Jay Fancher.  Originally posted at anthropologynow.wordpress.com

The Diversity of the African Genome & Traces of an Unknown Hominin

Tags

, , , , , , , , , ,

The most comprehensive look at the genome of Africans is published in the journal Cell today. The paper titled, “Evolutionary History and Adaptation from High-Coverage Whole-Genome Sequences of Diverse African Hunter-Gatherers,” focused on three hunter-gatherer populations; Pygmies from Cameroon and two groups from Tanzania, the Khoesan-speaking Hadza and Sandawe. The publication covered each of the genomes of five individuals from these groups over 60 times. The paper ultimately outlines some interesting findings, such as a new understanding on the extent of genetic diversity, and mysterious admixture.

We already have known that genetic diversity of people in Africa is greater than anywhere else on Earth. This knowledge plays into the concept of the the founder effect), where as we sample populations out of Africa, along the paths of migration of early Homo sapiens, we find that human populations tend to become more and more genetically similar the farther from the continent we go.

But just how diverse are some of the oldest living populations within Africa?

The authors discovered over 3.4 million genetic variants, or SNPs, of which a staggering 5-million of these variants are novel to us. Some of the loci give insight into adaptive changes in immunity, metabolism, olfactory and taste perception, reproduction, and wound healing. Interestingly, the Pygmy population, has multiple highly differentiated loci on genes on chromosome 3 which function in growth and anterior pituitary function and are associated with height.

We sequenced the whole genomes of five individuals in each of three different hunter-gatherer populations at >60× coverage and identify 13.4 million variants, substantially increasing the set of known human variation. We found evidence of archaic introgression in all three populations, and the distribution of time to most recent common ancestors from these regions is similar to that observed for introgressed regions in Europeans.

Of particular interest is that some of these SNPs aren’t found in any modern-day populations. This leads to the question if they originated due to ancient interbreeding between H. sapiens and an as-yet unidentified species of hominid. Lead author, Joseph Lachance, remarked how outstanding this is. Co-author Joshua Akey supports with,

Fossils degrade fast in Africa so we don’t have a reference genome for this ancestral lineage… one of the things we’re thinking is it could have been a sibling species to Neanderthals.

In the paper, the authors outline the great lengths they’ve taken show that the genetic traces resemble neither human nor Neanderthal DNA, and additionally document that none of the sequences taken from outside of Africa show any evidence of the foreign SNPs. All of which, has sparked Richard Klein to state that this conclusion to be as “irresponsible” particularly because there is no fossil evidence to support this mysterious sibling species.

Joseph Lachance, Benjamin Vernot, Clara C. Elbers, Bart Ferwerda, Alain Froment, Jean-Marie Bodo, Godfrey Lema, Wenqing Fu, Thomas B. Nyambo, Timothy R. Rebbeck, Kun Zhang, Joshua M. Akey, & Sarah A. Tishkoff (2012). Evolutionary History and Adaptation from High-Coverage Whole-Genome Sequences of Diverse African Hunter-Gatherers Cell : 10.1016/j.cell.2012.07.009

Moving The Moai

Tags

, , , , , , , , , ,

The Cover of National Geographic Magazine for July 2012

The July 2012 edition of the National Geographic magazine features a cover story on Easter Island’s statues and how these enormous 33 feet tall and 80 ton statues or moai came to existence. Just how the moai were constructed, transported and erected on Easter Island remains a mystery, one leading to a lot of speculation.

To my count, there have been five or so earlier theories on just how the moai were moved. In 1955, Norwegian ethnographer Thor Heyerdahl lead an experiment on Rapa Nui where he and 180 men tried to erect a 13 foot, 10 ton moai on a tree trunk and drag it. A Rapa Nui onlooker informed him how, “totally wrong,” he was.  He published two large volumes of scientific reports titled Reports of the Norwegian Archaeological Expedition to Easter Island and the East Pacific and later Heyerdahl added a third to the collection, The Art of Easter Island.

William Mulloy, an American anthropologist, theorized in 1970 the erection of the maoi using a desktop model. He thought he could swing the moai forward in steps while hanging the statue by the neck from an inverted wooden V structure. A photo of his model in deployment can be found on the Wikipedia page outlining his time on Rapa Nui. Sixteen years later, in 1986, Czech engineer Pavel Pavel along with Heyerdahl and 17 assistants walked on of the real 13 foot, 9 ton moai by using a twisting motion, and not a rocking motion. In doing so, they damaged the base, but the Wikipedia page on his efforts indicate success.

Within a year of Pavel’s trials, archaeologist Charles Love showed much more success. He and a team of 25 people stood up a replica 13 foot, 9 ton on a wooden sledge and then hauled it on rollers. In two short minutes they moved the replica 148 feet. Another American archaeologist, Jo anne Van Tilburg, gave it a shot in 1998. She and her team of 40 volunteers laid a 13 foot, 10 ton replica also on a wooden sledge. They were able to move the statue 230 feet, using a Polynesian wood ladder.

In the cover story, If They Could Only Talk, archaeologists Terry Hunt and Carl Lipo bring up a new theory one that is potentially plausible; three small groups of people balanced the statues on its base and transported it by guiding and waddling it along with ropes.

© Photo by Sheela Sharma
Three teams, one on each side and one in the back, manage to maneuver an Easter Island statue replica down a road in Hawaii, hinting that prehistoric farmers who didn’t have the wheel may have transported these statues in this manner. The experiment was led by archaeologists Terry Hunt and Carl Lipo and is reported in the July 2012 issue of National Geographic magazine.

The video below shows just how they do it:

The article also offers up a larger context and reinterpretation of the Easter Islanders, one which describes them as adaptable and sustainable,

“…based on their own archaeological survey of the island, they think its population grew rapidly after settlement to around 3,000 and then remained more or less stable until the arrival of Europeans.

Cleared fields were more valuable to the Rapanui than palm forests were. But they were wind-lashed, infertile fields watered by erratic rains. Easter Island was a tough place to make a living. It required heroic efforts. In farming, as in moai moving, the islanders shifted monumental amounts of rock—but into their fields, not out. They built thousands of circular stone windbreaks, called manavai, and gardened inside them. They mulched whole fields with broken volcanic rocks to keep the soil moist and fertilized it with nutrients that the volcanoes were no longer spreading.”

Additionally, Hunt & Lipo describe how the Rapanui people were the victims of genocide, decimated by disease introduced by Western explorers and 19th century slave trading, an idea that resonates with many other indigenous populations. Both ideas are at odds with the prevalent idea that the Rapa Nui people are one of the prime examples of ecocide, by exploiting their environment to the point of no return, as explained by Hunt himself in 2005 and supplemented by Jared Diamond’s Guns, Germs, and Steel and his later work, Collapse: How Societies Choose to Fail or Succeed.

These new ideas are thought-provoking and will fuel the discussion for years to come. If you would like to read more, be sure to pick up a copy of the article or check it out online. There is also an iPad app where you can read the paper and interact with multimedia features.

Google Supports The Endangered Languages Project

Tags

, , , , , , ,

On this site, we’ve covered endangered languages before, and in doing so we discussed the challenges faced in trying to preserve these priceless forms of cultural heritage and expression. It is a daunting task. I am happy to announce that Google has decided to help out the cause by funding and launching the Endangered Languages Project.

Screenshot of the Endangered Languages Project website

Screenshot of the Endangered Languages Project website

The Endangered Languages Project will act as a hub for interested groups and people to collaborate on research with the aim at documenting & preserving over 3,000 languages that are under threat of being lost to time. Google writes that the site will host resources to help keep some of those alive, such as high-quality recordings of people speaking the languages, copies of historical manuscripts, e-learning options, and even niche-language social networking opportunities, in addition to research and other documentation. They also write about long-term goals,

“…for true experts in the field of language preservation to take the lead. As such, in a few months we’ll officially be handing over the reins to the First Peoples’ Cultural Council (FPCC) and The Institute for Language Information and Technology(The LINGUIST List) at Eastern Michigan University. FPCC will take on the role of Advisory Committee Chair, leading outreach and strategy for the project. The LINGUIST List will become the Technical Lead. Both organizations will work in coordination with the Advisory Committee.”

Again, I am happy to see this initiative deployed. But I will hold with bated breath if this will truly benefit collaboration between linguistic academics or this is just a bit of nice PR like last year, when Google added Cherokee to its list of languages supported in search, though that option doesn’t seem to exist anymore. You can learn more about the project by watching this promotional video:

Were Paleolithic European Cave Paintings Made By Neanderthals?

Tags

, , , , , , ,

A new paper in the journal Science questions if it were Neanderthals or humans who created the oldest known artworks found in the caves of Europe. The lead author is Alistair W.G. Pike who worked with Joao Zilhao and nine other authors on this study.

Alistair W.G. Pike taking speleothems samples from a cave site in Spain for uranium-thorium (U-Th) dating.

The authors addressed this question in, “U-Series Dating of Paleolithic Art in 11 Caves in Spain,” by not dating the material of the painting themselves, but rather through dating mineral deposits known as speleothems (commonly known as stalagmites and stalactites, which can also be solid sheets of rock) that are found directly adjacent to the material. They analyzed the speleothems for the uranium to thorium ratios of over 50 pieces of cave art from 11 caves throughout Spain, of which three results were particularly intriguing.

The study relies on the concept that mineral forming rock flows over the walls of the caves covered in paleolithic art work. In doing so, it forms a sort of time capsule, meaning that anything encased within the flowstone is older than the flowstone itself. By comparing the ratio of atoms in the minerals deposited nearest the cave wall, the team was able to calculate the lower limit on the age of the art that lies just beneath.

U-Th ratios indicate that the red disk was made at least 40,800 years ago and the hand stencils were made 37,300 years ago.

The results show that cave art began in the Early Aurignacian period, at about 40,800 years ago for a red disk and 37,300 years ago for the hand stencil which is pictured above and 35,600 years for the claviform-like symbol pictured blow.

U:Th ratios indicate this calviform symbol was made at least 35,600 years ago.

If the earliest cave paintings appeared at around or before 40,800 years ago, then this the cave art coincides with the arrival of modern humans in western Europe which is thought to be 41,500 years ago. But since 40,800 is a minimum age for the earliest cave paintings, it cannot be ruled out that the cave paintings are works of Neanderthals who we know were in Spain at least 42,000 years ago… To know for sure we need samples dating older than 42, 43, 44,000 years ago.

Pike, A., Hoffmann, D., Garcia-Diez, M., Pettitt, P., Alcolea, J., De Balbin, R., Gonzalez-Sainz, C., de las Heras, C., Lasheras, J., Montes, R., & Zilhao, J. (2012). U-Series Dating of Paleolithic Art in 11 Caves in Spain Science, 336 (6087), 1409-1413 DOI: 10.1126/science.1219957

Follow

Get every new post delivered to your Inbox.

Join 7,806 other followers