The Application of Forensic Dentistry through Multiple Means

Forensic dentistry or forensic odontology is a discipline that applies dental knowledge to criminal and civil laws. It is responsible for areas including identification of found human remains, identification in mass fatalities, and age estimation.

Disaster types and modes of identification of victims

The first case in which a dentist used dental evidence in a court case demonstrated the method of Comparative Dental Identification. In 1814, a lecturer of anatomy Dr. Granville Sheep Pattison and two of his students in Scotland were charged for the violation of Mrs. Mc Alister grave. They have moved the body of Mrs. Alister after the burial to the nearby college. Mrs. Alister’s dentist Dr. James Alexander testified that the maxillary denture of one of the heads in the dissection room fit Mrs. Alister. The dental identifications of individuals are also effective after mass fatalities, such as the Sumantra Andaman earthquake and Tsunami waves in Indian Ocean in 2004. More than 92% of non-Thai were identified ,and out of them 80% were identified by dental formation.

The dental features on postmortem remains can be compared with ante mortem dental records, including written notes, study casts and radiographs. In the system of identification, dental restorations, similarities and discrepancies are noted. How are the discrepancies formed? In some cases, they are related to time lapse between ante mortem and post-mortem records; while in other situations, the discrepancies are unexplainable. Thus, there are four conclusions recommended when reporting identification results: positive identification, possible identification, insufficient evidence, and exclusion.

Postmortem PM (a) and ante mortem AM (b) dental radiograph with many restorations (dense radio opacity)

One process about forensic dentistry is to recover the life of a set of human remain: we can not only identify this person’s physical features, but also decipher the life experiences, such as socio-economic status includes occupation, dietary habits, and habitual behaviors, dental or systemic diseases. Erosion can suggest alcohol, substance abuse, an eating disorder or even hiatus hernia, while stains can indicate smoking, tetracycline use or betel nut chewing. The quality, quantity, presence or absence of dental treatment may indicate socioeconomic status or country of residence. These dental profiles can help forensic artists construct a facial reproduction.

Forensic dentistry is also utilized to determine the age, ancestry, and sex. For example, in 1897, due to the story which said another child instead of Prince Louis XVII was buried in the monument, three experts aged the skeleton near the side of the church at between 16 plus and 18 plus years, proving that the remains were not Dauphin. What’s more, a forensic dentist can determine race within three major groups (Caucasoid, mongoloid and negroid) from skull appearance and tooth features such as cusp of Carrabelle, shovel-shaped incisors and multi cusped premolars. Sex can be examined by the presence or absence of y-chromatin and DNA analysis.

References:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4439663/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4111024/

Campbell JM. Glasgow: Pickering and Inglis, Ltd; 1963. Dentistry then Now.

Schuller-Götzburg P, Suchanek J. Forensic odontologists successfully identify tsunami victims in Phuket, Thailand. Forensic Sci Int. 2007;171:204–7.

Craniofacial identification by comparison of antemortem and postmortem radiographs: two case reports dealing with burnt bodies. Campobasso CP, Dell’Erba AS, Belviso M, Di Vella G Am J Forensic Med Pathol. 2007 Jun; 28(2):182-6.

Body identification guidelines. American Board of Forensic Odontology Inc. J Am Dent Assoc. 1994 Sep; 125(9):1244-6, 1248, 1250 passim.

Amoedo O. Paris: Masson Co., Booksellers L’Academie of Medicine; 1898. Dentistry in Forensic Medicine.

[Studies on sex determination using human dental pulp. II. Sex determination of teeth left in a room]. Adachi H Nihon Hoigaku Zasshi. 1989 Feb; 43(1):27-39.

Review A look at forensic dentistry–Part 1: The role of teeth in the determination of human identity. [Br Dent J. 2001]

Further Reading:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4149164/

https://www.adc-fl.com/dental-anthropology-and-bioarchaeology/

Images:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4439663/

Obsidian: Ancient Tools have Modern Purpose

Since ancient times, obsidian rock has been useful in tool making, as well as serving many other purposes. Obsidian is an igneous rock which is rich in silica and has a low water content. It appears black and shiny in its pure form but is often covered in an outer layer that is more brown in color and appears dull and rough. Obsidian rock was used by early human civilizations to create tools such as arrowheads, blades, and other sharp objects. It is also suggested that obsidian tool knapping could have been used in some cultures as a way for male knappers to impress potential female partners. Using knapping- the creation of stone tools by way of percussion- early humans were able to produce almost-modern objects, some of which are still being utilized today.

Two arrowheads produced from obsidian through the process of knapping. Arrowheads would only be found in areas where hunting by bow and arrow was prevalent.

Obsidian is especially useful for its sharp properties, and this is the reason obsidian tools are still on the market and being studied and used in the twenty first century. Obsidian has incredibly useful and unique properties. The average household razor blade is somewhere between 300 and 600 angstroms (unit of measurement used to measure blade fineness). An obsidian blade measures in at only 30 angstroms, making it very useful in precise cutting. For its extreme sharpness, modern surgeons have continued to utilize obsidian tools in their work, especially in precise surgeries.

Specifically, Dr. Lee Green at the Department of Family Medicine at the University of Alberta says it is not uncommon for him to use obsidian blades in his work. Obsidian’s makeup creates a smooth and continuous edge on a blade, while regular steel tools have a rough edge on their blades at a microscopic level, which can tear into tissue and leave the patient with a longer healing process and more intense scarring. Green has observed that following procedures with obsidian scalpels, patients experience much less scarring than in the same procedure done with steel tools.

A modern obsidian scalpel. These scalpels can be used for precise cutting in surgery.

While it may seem odd to be using tools from the stone age in modern medicine, the blades being used today are different than those of ancient humans. Dr. Green receives his obsidian scalpels from an expert flint knapper, Errett Callahan. Green also knows that using obsidian in medicine is a technique is not useful for every procedure and for every surgeon. Obsidian tools have their time and place. The scalpels can also be helpful for patients who might be allergic to the materials used for most surgical tools, such as steel and metal.

 

Sources:

Shadbolt, Peter. “How Stone Age Blades Still Cut It in Surgery.” CNN, Cable News Network, 2 Apr. 2015, www.cnn.com/2015/04/02/health/surgery-scalpels-obsidian/index.html.

King, Hobart M. “Obsidian.” Geology, geology.com/rocks/obsidian.shtml.

Britannica, The Editors of Encyclopaedia. “Obsidian.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 10 May 2018, www.britannica.com/science/obsidian.

 

Additional Readings/videos

https://www.ncbi.nlm.nih.gov/pubmed/8415970

Pictures:

https://www.spectrum-scientifics.com/Obsidian-Replica-Arrowhead-p/5826.htm

https://www.cnn.com/2015/04/02/health/surgery-scalpels-obsidian/index.html

 

What the Temple of Ebla Tells Us About the Cult of Ishtar

According to Babylonian myth, Ishtar––known as Inanna in Sumerian Myth––was a powerful goddess who had control over war and love; she brought forth rain and thunderstorms, which, since her myth was mostly rooted in Mesopotamia, served a central role in the agricultural aspects of daily life. Ishtar, often represented by doves, was also the goddess of fertility and was revered by many, both of high and low status. As Ishtar rose in prominence, she became central in Babylonian and Sumerian society, and thus became the central figure in the Cult of Ishtar, which expanded throughout the Babylonian and Sumerian sphere of influence. How do archaeologists identify evidence for these cults? Ebla, a town located in modern day Syria, is presumed to be highly influenced by the Cult of Ishtar; the evidence found in the town’s religious temples could help archaeologists accurately describe the goddess and her worshippers, as well as describe the affect that the cult had on the society.

This image is a relief of Ishtar, the Babylonian goddess of fertility, war, and love.

In order to determine the location of a cult, archaeologists must first find attention-focusing devices, such as sacred temples, where the community would presumably go to worship. In Ebla, temples were discovered; religious practices most likely took practice in a central space, bounded by cisterns. Archaeologists found the most evidence for the presence of Ishtar within the temple; As archaeologists began to excavate the stratigraphy around in a favissa, or pit, they discovered a plethora of artifacts, including carnelian lions, bronze bulls, and bronze snakes: all common iconography of Ishtar. The addition of figurines depicting domesticated animals and naked women––symbols of fertility––also suggest Ishtar’s influence within Ebla.

This image depicts the remains of a temple at Elba in modern-day Syria, a site that suggests influence from the Cult of Ishtar.

The archaeologists also began to find pottery sherds dumped in pits, which were then hypothesized to be influenced by the Cult of Ishtar; though they were unable to be completely reconstructed, the decorations of the pottery often depicted a common theme of birds. These birds however, were most likely doves than birds of prey; this hypothesis is supported by the presence of dove bones on the site, which were most likely used as offerings towards the goddess. The presence of doves suggests that Ishtar’s sphere of influence had expanded beyond the Tigris and Euphrates rivers. Though the pottery is not complete evidence for the Cult’s presence, the contents within the pottery is what deems their religious significance. The pottery obtained at the site contained burnt offerings, such as processed food and bones; this signifies the town’s participation in the offering­­s, another major aspect of cult identification.

These findings within the temples’ favissa suggests that Ishtar’s influence was expanding westward, which indicates the Babylonian and Sumerian sphere of influence was growing towards the Mediterranean, allowing their culture to be adopted by more people.

 

Additional Readings:

https://www.brooklynmuseum.org/eascfa/dinner_party/place_settings/ishtar

https://www.ancient-origins.net/ancient-places-asia/ishtar-gate-and-deities-babylon-001868

https://www.ancient.eu/Ishtar_Gate/

Sources:

Heffron, Yaǧmur. “Inana/Ištar (goddess)”, Ancient Mesopotamian Gods and Goddesses, Oracc and the UK Higher Education Academy, 2016 http://oracc.iaas.upenn.edu/amgg/listofdeities/inanaitar/

Marchetti, Nicoló. Nigro, Lorenzo.

1997  Cultic Activities in the Sacred Area of Ishtar at Elba During the Old Syrrian Period: the Favissae F.5327 and F.5238 Journal of Cuneiform Studies (49): 1-44.

Pinnock, Frances.

2000  The Doves of the Goddess. Elements of the Cult of Ishtar at Elba in the Middle Bronze Age Levant (32:1): 121-128.

Renfrew, Colin, and Bahn, Paul G. Archaeology Essentials: Theories, Methods, Practice. 2nd ed., Thames & Hudson, 2015.

Pictures:

https://www.allposters.com/-sp/Relief-Depicting-Ishtar-and-Tyche-in-the-Likeness-of-Queen-Zenobia-and-Her-Servant-Posters_i12163148_.htm

http://www.ebla.it/escavi__i_templi_paleosiriani.html

 

Tracing Galena Artifacts at Poverty Point Back to their Source

The Poverty Point archaeological site in northeastern Louisiana is most widely known for its massive earthen mounds measuring up to 72 feet tall and forming six concentric semicircles. At its height from 1200 BCE to 700 BCE, the Poverty Point Native American site had an estimated population of around 5,000 and its advanced architecture and tools indicate a thriving society.  Not only is Poverty Point an architectural wonder, it also serves as an indicator of a widespread trading network throughout the Midwest and Northeast. Stones and artifacts from as far as 1000 miles have been found by archeologists at Poverty Point.

When archeologists first began observing large amounts of stone artifacts at Poverty Point, they were able to identify the key element in many of the artifacts as galena, a shiny silver form of lead (II) sulfide. By 1970, over 700 artifacts containing galena had been identified at Poverty Point and four smaller surrounding settlements. The most common galena artifacts are bird effigy pendants, oval pendants, beads, and polished rectangles.

Galena has been found in a wide range of artifacts at Poverty Point including pendants, beads, polished rectangles and stones. Archeologists believe that these artifacts were often used for ceremonial and decorative purposes at Poverty Point as well as other Native American sites throughout the Southeast.

Archeologists used trace element analysis, the process of identifying elements present in small amounts, in order to trace a material back to its source of origin. Trace element analysis of galena artifacts at Poverty Point indicated that the majority of the rocks originated from the Potosi deposit in Missouri while others were from the upper Mississippi valley. Archeologists also conducted trace element analysis of galena artifacts at seven other Native American sites and found that 55% of the artifacts could be traced to the Potosi deposit and 34% to the upper Mississippi valley while the other 11% was inconclusive. Because of this evidence, archeologists were able to identify a trading pattern that used the Mississippi River, the Ohio River and the Arkansas River as well as the Ouachita stream and stopped at sites including Yazoo Basin and a Native American settlement at Calion.

Galena was by no means the only material traded at Poverty Point. This map shows the source areas for other minerals found at Poverty Point in addition to the two main galena source points which are marked as A and C on this map.

Archeologists have also noted a highly similar style of bird pendants made from galena in four different locations along the Mississippi and Ohio Rivers indicate that galena was traded both as a raw material and as a finished product. This exhibits the shared cultural importance of galena while also indicating variations in cultural traditions.

Additionally, this trade is especially interesting to archeologists as it does not follow the theory of fall off analysis which states that the quantity of a material will decrease with the distance from the source of that material. There are many more galena artifacts at the Poverty Point site in Louisiana than there are at sites closer to the Potosi deposit. This indicates that the trade was not simply a reciprocal exchange, but rather a more complicated directional trading pattern. The Poverty Point trading network is one of the first instances of large scale long distance trade in the Americas that can be fully shown by archeologists. It represents an extremely important development in society as well as social organization.

Additional Readings:

Feasting at Poverty Point

http://pu6xa6xs3q.search.serialssolutions.com/?ctx_ver=Z39.88-2004&ctx_enc=info%3Aofi%2Fenc%3AUTF-8&rfr_id=info%3Asid%2Fsummon.serialssolutions.com&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Feasting+at+Poverty+Point+with+Poverty+Point+Objects&rft.jtitle=Southeastern+Archaeology&rft.au=Hays%2C+Christopher+T&rft.date=2018-07-17&rft.issn=0734-578X&rft.eissn=2168-4723&rft.spage=1&rft.epage=15&rft_id=info:doi/10.1080%2F0734578X.2018.1496315&rft.externalDBID=n%2Fa&rft.externalDocID=10_1080_0734578X_2018_1496315&paramdict=en-US

Trace Element Analysis on Pottery from Oaxaca

https://www.amnh.org/our-research/anthropology/research/meso-american-archaeology/projects/10.-trace-element-analysis

References

Hays, Christopher T, Richard A Weinstein, and James B Stoltman

2016 Poverty Point Objects Reconsidered. Southeastern Archeology

Hill, Mark A, Diana M Greenlee, and Hector Neff
2016 Assessing the provenance of Poverty Point copper. Journal of Archaeological Science 6: 351–360

Louisiana Division of Archaeology

2014 Discover Archaeology. Louisiana Department of Culture, Recreation and Tourism

Walthall, John A, Clarence H Webb, Stephen H Stow, and Sharon I Goad

1982 Galena Analysis and Poverty Point Trade. Midcontinental Journal of Archaeology 7: 133–148

 

Image Citations:

Material Source Map. Louisiana Archaeology Project

https://www.crt.state.la.us/dataprojects/archaeology/virtualbooks/POVERPOI/trade.htm

 

Galena Artifacts. Louisiana Division of Archaeology

https://www.crt.state.la.us/dataprojects/archaeology/povertypoint/ceremonial-life.html

‘Archaeogenetics’ and the Ancient Beringians

‘Archaeogenetics’, the study of ancient DNA, has opened the door to further understanding Earth’s complex history through examination of humans, animals, and plants. With DNA being a dependable ‘artifact’ in itself, archaeologists can learn much more about the people who once populated the sites they examine.

Many know the story of how North America was “discovered” by white, European explorers, but the origins of the Native Americans they drove away has continued to remain a bit nebulous. However, in 2013, the body of a young girl recovered from a burial pit in Alaska assists in reaching an answer about their origin; the significance lies in her DNA that, when analyzed in 2017, matched Native Americans as well as “ancient north Eurasians who lived in what is now Siberia” (Sample).

Archaeologists at the Upward River Sun site in Alaska where the body of the ancient Beringian girl, named “Xach’itee’aanenh t’eede gaay” (“sunrise-child girl”), was found (Sample).

Examining ancient DNA is complex and often cannot be done, as genetic material degrades easily. Viviane Slon of the Max Planck Institute for Evolutionary Anthropology explains, “not every fossil will yield DNA, and not every fossil will yield enough DNA to reconstruct a full genome” (Moscato). In fact, “the best environments for preserving DNA tend to be cold, dry and stable over long time periods” (Moscato), like that of Alaska.

The body of this young girl yields support of the early Native Americans traveling to America by way of East Asia (Sample). Because ice caps held so much of the ocean’s water during the Ice Age, an open land bridge spanned from Russia to Alaska where the Bering Strait is currently (Tamm; Sample; Renfrew and Bahn 140). The land bridge, called Beringia, housed people from East Asia in addition to acting as a “byway” to a new land.

However, geneticists realized that the remains of the girl recovered were genetically different from modern Native Americans, proving the existence of the previously unknown “ancient Beringians” (Sample). About 34,000 years ago, a group of individuals began to separate from the Asians. By 20,000 years ago, today’s Native American ancestors split off from the ancient Beringians, heading into now-North America and forming the “northern and southern branches” all Native Americans trace back to (Strickland; Moreno-Mayar; Tamm).

This diagram details the formation of Native American populations from early ancestors — Ancient Beringians split off from Ancestral Native Americans about 20,000 years ago with their subsequent movement unknown.

Inevitably, the limits of understanding the people of the past become apparent as there is a shortage of tangible proof of ancient Beringians being on Beringia and where they went after. One can only answer so many questions without exhibiting more speculation than corroborated truth. It is like constructing the outside frame of a puzzle, but not having many connecting pieces on the inside. The traces of ancient Beringians are waiting to be discovered and shared with the world to provide answers about this incredible, lost community.


Works Cited

Cohen, Jennie. “Native Americans Hailed From Siberian Highlands, DNA Reveals.” History.com, A&E Television Networks, 26 Jan. 2012, www.history.com/news/native-americans-hailed-from-siberian-highlands-dna-reveals.

Moreno-Mayar, J. Víctor, et al. “Terminal Pleistocene Alaskan Genome Reveals First Founding Population of Native Americans.” Nature, vol. 553, no. 7687, 2018, pp. 203–207., doi:10.1038/nature25173.

Moscato, David. “The Incredible Science of Ancient DNA.” Earth Touch News Network, Earth Touch, 6 Feb. 2018, www.earthtouchnews.com/natural-world/how-it-works/the-incredible-science-of-ancient-dna/.

Renfrew, Colin, and Paul G. Bahn. Archaeology Essentials: Theories, Methods, Practice. 3rd ed., Thames & Hudson, 2015.

Sample, Ian. “Surprise as DNA Reveals New Group of Native Americans: the Ancient Beringians.” The Guardian, Guardian News and Media, 3 Jan. 2018, www.theguardian.com/science/2018/jan/03/ancient-dna-reveals-previously-unknown-group-of-native-americans-ancient-beringians.

Strickland, Ashley. “11,500-Year-Old Infant Remains Reveal Ancient Population.” CNN, Cable News Network, 5 Jan. 2018, www.cnn.com/2018/01/05/health/ancient-population-discovery-alaska-trnd/index.html.

Tamm, Erika, et al. “Beringian Standstill and Spread of Native American Founders.” PLoS ONE, vol. 2, no. 9, 2007, doi:10.1371/journal.pone.0000829.

 

Images

https://thumbs-prod.si-cdn.com/CEg9yf-zqGgsDK0AhEMLKXj_h6o=/1072×720/filters:no_upscale()/https://public-media.smithsonianmag.com/filer/f8/3d/f83d9a08-978f-42fa-9ebd-0428fb2e1b74/101610_web.jpg

https://www.thesun.co.uk/wp-content/uploads/2018/01/nintchdbpict000376128856.jpg

 

Additional Resources

https://www.nps.gov/bela/learn/historyculture/the-bering-land-bridge-theory.htm

https://www.scientificamerican.com/article/first-americans-lived-on-bering-land-bridge-for-thousands-of-years/     


Pollen Dating

 

Pollen dating, is one of the lesser utilized methods archaeologists have to determine a relative chronology or timeframe for a certain event. Pollen dating can determine a relative time frame far earlier than radiocarbon dating is able. Although, because of influences such as pollen transportation by wind for thousands of miles and the abundance of certain kinds of pollen, radiocarbon dating is necessary to give absolute dates.

Pollen dating is done by comparing the pollen zones in different rock layers or strata, comparing older, deeper layers to newer ones on top. The pollen zone is the particular time frame where specific species of plants release more pollen into the air than others. Using this, archeologists can determine climate changes, deforestation, or changes in the use of land hundreds of years ago such as the association between European settlement in North America and an increase in the amount of ragweed pollen found. Specific locations can even be determined as the origins for many rare or uncommon pollens.

 

Pollen can come in a variety of distinct shapes and sizes depending on the plant it is coming from. These microscopic grains are incredibly sturdy with outer shells made from sporopollenin, an incredibly inert substance. This allows the pollen to stay intact for thousands of years, especially when preserved in bodies of water, peat or, lake sediment. Ireland’s bogs are full of sediments and pollen, with certain layers linked to events such as the eruption of Icelandic volcanoes in 1104, 1362, and 1510 and an agricultural shift after the Black Death.

 

By looking at the sedimentary build up of pollen at the microscopic level, 400-1000x magnification, the pollen grains can be identified and the taxa concentrations determined, which can paint a picture of the climate as it changed over time.

 

Pollen can also be collected from the inside of pottery such as pots and stone tools, trapped in the fabric of clothes, the the cracks of floors and walls, or on other archeological artifacts and features. This can be used to help determine the diets of a people, their crops, and the materials they used to build their homes. By looking at these specific pollen samples as well as the layer of accumulated pollen, researchers can develop a better understanding of the environment and biodiversity throughout the history of an area.

 

Pollen grains from different plants, 3D illustration. They are factors causing hay fever and allergic rhinitis Stock Illustration - 84820593

Pollen magnified

https://www.123rf.com/photo_84820593_stock-illustration-pollen-grains-from-different-plants-3d-illustration-they-are-factors-causing-hay-fever-and-allergic-.html

pollen core sampling

Two researchers taking core samples

https://www.crowcanyon.org/index.php/palynology

 

Extra Links:

https://www.jstor.org/stable/20210068?seq=1#metadata_info_tab_contents

https://www.encyclopedia.com/earth-and-environment/ecology-and-environmentalism/environmental-studies/pollen-analysis

 

Citations:

Hirst, K. Kris. “How Does Palynology Inform Paleoenvironmental Reconstruction?” ThoughtCo, ThoughtCo, 8 Mar. 2017, www.thoughtco.com/palynology-archaeological-study-of-pollen-172154.

“Picture Climate: How Pollen Tells Us About Climate.” National Climatic Data Center, www.ncdc.noaa.gov/news/picture-climate-how-pollen-tells-us-about-climate.

The Irish Times. “Pollen Dating Paints Picture of Our Past.” The Irish Times, The Irish Times, 24 Feb. 2013, www.irishtimes.com/news/pollen-dating-paints-picture-of-our-past-1.365947.

 

Discoveries that challenge the textbook’s World Chronology

Human beliefs are always in constant change. Humanity’s growth is inevitable, and the more we evolve, the more our prior beliefs are challenged by new discoveries. Our technological advancements have aided in accelerating our growth.

 

One of the most beneficial technological advancements for archaeologists was ability to produce absolute dates. These techniques have helped solidify our beliefs in human migration, as well as challenge them. By using dating techniques, such as radiocarbon and uranium series dating, archaeologists have been able to determine the span of time in which humanity began to spread across the globe.  

 

The beginning of humankind is believed to have originated in Africa. Then, some 60,000-50,000 years ago the exodus from Africa, also known as the “Out of Africa” expansion, began (Renfrew 134). However, multiple recent discoveries have challenged these widely accepted dates of migration.  

 

 

 

In April of 2018, archaeologists from the Max Planck Institute for the Science of Human History in Germany discovered an 85,000 year old human finger bone in the Saudi Arabian dessert. This is the oldest human bone to be found outside of Africa or the Levant. Archaeologists used uranium series dating, which uses the radioactive decay of isotopes of uranium, to date the bone (Renfrew 127). Forty seven human teeth found in Fuyan Cave in Daoxian, southern China, were dated from 80,000 up to 120,000 years ago. Even more of this trend of discoveries have been made around the world, in Israel and Australia, which go against the textbook dates of world chronology (Flynn).

View of the excavation for the 85,000 year old human finger bone in the Saudi Arabian dessert

These discoveries have created questions in regards to how the “Out of Africa” expansion took place. It was believed that the migration was done so in a collective way, however, these findings suggest the migration began 20,000-25,000 thousand years earlier than previously thought (Scott). The location of the bone, far into what was thousands of years ago a grassland, also indicates that humans had traveled much farther. Studies into this discovery also shows that humans migrated little by little instead of all together at once. These findings could even push back the date of Homo Sapiens evolution back even further.

Textbook chronological map of human migration

The world of archaeology is ever expanding; what seems to be a universal theory now can easily be replaced tomorrow. Advancements in technology will continue to aid in the search for new information. With every new update in equipment comes information we had not been previously able to obtain.

 

Additional readings

“Earliest Human Remains Outside Africa Were Just Discovered in Israel.” www.smithsonianmag.com/science-nature/earliest-humans-remains-outside-africa-just-discovered-israel-180967952/.

Human remains from Zhirendong, South China, and modern human emergence in East Asia”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2984215/

 

Work cited

Scott, Katy. “Ancient Finger Bone Could Challenge Theory of Modern Migration.” CNN, Cable

News Network, 9 Apr. 2018, www.cnn.com/2018/04/09/health/saudi-arabia-fossil-finger/index.html.

Flynn, Meagan. “An 85,000-Year-Old Finger Fossil May Challenge Theories about How Early

Humans Migrated from Africa.” The Washington Post, WP Company, 10 Apr. 2018,

www.washingtonpost.com/news/morning-mix/wp/2018/04/10/an-85000-year-old-finger-f

ossil-may-challenge-theories-about-how-early-humans-migrated-from-africa/?noredirect

=on&utm_term=.081aba75ebd8.

Bahn, Paul and Colin Renfrew 2010  Archaeology Essentials. 2nd Edition Thames & Hudson              —–x—-Inc., New York, NY.

 

 

Image Sources

Bahn, Paul and Colin Renfrew 2010  Archaeology Essentials. 2nd Edition Thames & Hudson              —–x—-Inc., New York, NY.

Flynn, Meagan. “An 85,000-Year-Old Finger Fossil May Challenge Theories about How Early

Humans Migrated from Africa.” The Washington Post, WP Company, 10 Apr. 2018,

www.washingtonpost.com/news/morning-mix/wp/2018/04/10/an-85000-year-old-finger-f

ossil-may-challenge-theories-about-how-early-humans-migrated-from-africa/?noredirect

=on&utm_term=.081aba75ebd8.

Argon-Argon Dating and Hominid Skulls in Herto, Ethiopia

Three fossilized hominid skulls were found near Herto, Ethiopia in 1997. The skulls were determined to be those of two adults and one child. The remains were too old to be dated using radiocarbon dating. In order to determine the age of the artifacts found at Herto (Figure 1), scientists performed argon-argon dating on volcanic rock that was found near the artifacts (Zielinski 2008).

Figure 1. A map showing the location of Herto, Ethiopia, the village the hominid skulls were found near.

There are multiple radiometric methods of dating artifacts. Some of these radiometric methods include radiocarbon dating, potassium-argon dating, uranium-series dating, and fission-track dating (Renfrew 2010:120-129). Potassium-argon dating, which measures the ratio of potassium-40 to argon-40, is one radiometric method, but this method of dating is not as precise as argon-argon dating. Scientists converted potassium-40 to argon-39. This allowed the scientists to use argon-argon dating. The volcanic rock analyzed by scientists at Herto were found to be around 154,000 to 160,000 years old (Zielinski 2008).

The hominid skulls found at Herto are important discoveries because at the time of their discovery, they were some of the oldest near-modern human remains on record (Graham 2003). Based on archaeological artifacts like the ones found at Herto, artists have created depictions of near-modern humans (Figure 2). The Homo sapiens remains found at Herto, which were distinct from Homo neanderthalensis remains, were given a subspecies name, Homo sapiens idaltu. Other artifacts from the same time period were found near the fossilized skulls. Some of these artifacts include stone tools and animal bones with marks from tools. Additionally, cut marks on the skulls are indicative of the mortuary practices and rituals of the early humans (Sanders 2003). These marks and tools, which include hand axes, help the people of today understand how Homo sapiens lived over 100,000 years ago.

Figure 2. An artist’s depiction of a near-modern human.

Scientists claim the analysis of the Herto hominid skulls supports claims made by molecular anthropologists. Before the discovery of the Herto artifacts, molecular anthropologists have claimed modern humans evolved out of Africa (Sanders 2003). The discovery of near-modern human skulls in Herto, Ethiopia supports this Out of Africa hypothesis. Before the discovery of the Herto artifacts, other Homo sapiens remains had been discovered in Ethiopia and other African countries. The ages of these other remains range from 80,000 years old to 130,000 years old (Sanders 2003). Since the discovery of the Homo sapiens idaltu fossils near Herto, remains found in Jebel Irhoud, Morocco have been found to be about 315,000 years old, making them the oldest Homo sapiens remains on record (Callaway 2017). While the Herto remains may no longer be considered the oldest Homo sapiens remains on record, the discovery was important in the understanding of the origins of Homo sapiens and illustrates the importance and usefulness of radiometric dating methods like argon-argon dating.

Additional Content

An article that details the importance of dating methods in the Herto discovery and other discoveries: https://www.smithsonianmag.com/history/showing-their-age-62874/

An article about the Jebel Irhoud Homo sapiens discoveries: http://www.sciencemag.org/news/2017/06/world-s-oldest-homo-sapiens-fossils-found-morocco

References Cited

Callaway, Ewen
2017 Oldest Homo sapiens fossil claim rewrites our species’ history. Electronic document,
https://www.nature.com/news/oldest-homo-sapiens-fossil-claim-rewrites-our-species-history-1.22114, accessed September 19, 2018.

Graham, Sarah
2003 Skulls of Oldest Homo sapiens Recovered. Electronic document,
https://www.scientificamerican.com/article/skulls-of-oldest-homo-sap/, accessed September 19, 2018.

Renfrew, Colin, and Paul Bahn
2010 Archaeology Essentials. 2nd ed. Thames & Hudson, New York.

Sanders, Robert
2003 160,000-year-old fossilized skulls uncovered in Ethiopia are oldest anatomically modern humans. Electronic document,
https://www.berkeley.edu/news/media/releases/2003/06/11_idaltu.shtml, accessed September 18, 2018.

Zielinski, Sarah
2008 Showing Their Age. Electronic document,
https://www.smithsonianmag.com/history/showing-their-age-62874/, accessed September 18, 2018.

Image Sources

Amos, Johnathan
2003 Oldest human skulls found. Electronic document,
http://news.bbc.co.uk/2/hi/science/nature/2978800.stm, accessed September 19, 2018.

Sanders, Robert
2003 160,000-year-old fossilized skulls uncovered in Ethiopia are oldest anatomically modern humans. Electronic document,
https://www.berkeley.edu/news/media/releases/2003/06/11_idaltu.shtml, accessed September 18, 2018.

What Trees Can Tell Us About the Past : The Importance of Dendrochronology

Image

 

Dendrochronology is a scientific method that uses the annual growth rings on trees to find out the exact year the tree was formed, which helps scientists date events, environmental change, and archaeological artifacts.  A tree’s rings start from the middle, with the oldest rings at the center of the tree and new growth occurring in a layer of cells near the bark. The rate at which the tree grows changes in a predictable pattern throughout the year due to seasonal climate changes, which causes visible growth rings.  Each ring on a tree represents a full year in the life of the tree.

Not only can these rings tell us how old a tree is, but each ring can show what the climate was like during that year.  In temperate climates, a tree will grow one ring each year. In the spring, there is more moisture, so the cells of a tree expand quickly.  In the summer, however, it becomes very dry and the tree cells start to shrink. When looking at tree rings, this change is cell size is visible and results in different sized widths of rings.  The rainier the year, the wider the ring and vice versa.

Not all trees are datable, due to factors such as natural tree variation and too much water, but about 40% of trees can be dated.  Simply counting the rings on a tree sample tells us how old the tree was when it was cut down, but to find out what time period the tree is from requires a little more work.  Scientists must look at the pattern of the rings, not just how many there are to find out the time period the tree is from. All trees in the same climate or region will have rings forming the same pattern, since a rainy year or a drought will affect all trees the same way.  To know if trees are from the same climate or region scientists must simply match the tree rings. This is possible, since tree ring patterns never repeat themselves, so they are specific to a time and place.

Skeleton Plotting: the graph paper is being marked where there are narrow rings

The process of identifying a pattern is not as complicated as it would seem.  Dendrochronologists lay a strip of graph paper on a sample of tree and mark where the narrow rings are.  This process is called Skeleton Plotting, since it is only marking the seasons of drought. It is easier to identify patterns by hand rather than by computer, because humans are so good at recognizing patterns.  Dendrochronologists will repeat this process for thousands of trees from the same region or climate to create a master pattern, which is called a master chronology.

Work Cited

Labeled Tree Sample. NASA, 25 Jan. 2017, climate.nasa.gov/news/2540/tree-rings-provide-snapshots-of-earths-past-climate/.

Mason, Matthew. “Dendrochronology: What Tree Rings Tell Us About Past and Present.” EnvironmentalScience, www.environmentalscience.org/dendrochronology-tree-rings-tell-us.

Skeleton Plotting. PBS, 30 Jan. 2013, www.pbs.org/time-team/experience-archaeology/dendrochronology/.

“Tree Ring Dating Dendrochronology.” PBS, 30 Jan. 2013, www.pbs.org/time-team/experience-archaeology/dendrochronology/.

Tree Sample. PBS, 30 Jan. 2013, www.pbs.org/time-team/experience-archaeology/dendrochronology/.

 

Additional Content

https://www.pbs.org/video/time-team-america-dendrochronology/

 

Crystal Skull Forgery

In the mid 1800’s Crystal skulls began to circulate, some even finding their way into museums – claiming to be made by pre-Columbian peoples. Although these allegedly magical artifacts raised suspicion among historians and archaeologists for almost a century, they remained in museum collections. However, in 1992 one notable example, The Smithsonian Skull, was donated anonymously to the British Museum, and this event finally moved American and British archaeologists to begin research that led to the debunking of these mysterious artifacts.

Though the Smithsonian Skull was donated anonymously, many other similar crystal skulls were traced back to the 19th century French antiquity dealer, Eugene Boban. Boban had sold the skulls to art dealers claiming they were ancient aztec artifacts, exploiting the imagination of the ignorant buyers. With this forged pre-Columbian provenance, the skulls found their way into both the British Museum and The Quai Branly Museum in Paris.

As research on these skulls commenced, the initial evidence of falsification was the fact that the Smithsonian skull had come from an undocumented site. Furthermore, as crystal can not be carbon dated, no absolute dating method had ever been used to test the authenticity of the skulls. However, archaeologists used relative dating to compare the style of real Aztec skull symbolism to the crystal skulls, and a discrepancy was found in representation of teeth. In the crystal skulls, teeth had been created in linear, symmetrical rows – unlike the more natural pattern of the Aztec designs. Archaeologists also used relative dating methods to compare surface etchings. On the surface of an authentic, Aztec, crystal goblet, etchings showed variance – signs of a handcrafted object. However, the crystal skull etchings showed the use of a rotary wheel, which was only introduced after the Spanish Conquest. The relative date Archaeologists had begun to consider of at least the late 1500’s, was then cross checked using an X-ray diffraction system. The researchers found leftover residue of silicon carbide: an abrasive material used for smoothing in stone carving workshops beginning in the 20th century. Lastly, iron-rich chlorite mineral traces that were found in the crystal of the skull suggested that the crystal material wasn’t even naturally occurring in the Yucatan region, but rather from Brazil or Madagascar.

    The story of the Smithsonian Skull highlights the importance of empiricism in archaeology. Though Babon did sell fake artifacts, he had also traded real ones – making it likely that he knew he was selling forges, but let his personal bias and motivations for profit allow him to look past this. On the other hand, British and American researchers had to look past their own possible, natural biases in order to question the authenticity of the crystal skulls – which up to this point had been ignorantly assumed to be pre-Columbian. Lastly, this series of events shows the importance of the use of multiple dating methods to cross check, and how relative dating can become crucial in artifacts that do not allow absolute dating methods.

The image above is an authentic pre-Columbian skull mask carved in stone from the 1st century AD.

The image above is the Smithsonian Skull sent to the British Museum in 1992.

Work Cited
“Ancient Costa Rica Stone Underworld Skull Deity Death Mask.” Busacca Gallery , www.busaccagallery.com/catalog.php?catid=157&itemid=6383.

Everts, Sarah. “Crystal Skulls Deemed Fake.” CEN RSS, American Chemical Society, 4 Mar. 2013, https://cen.acs.org/articles/91/i9/Crystal-Skulls-Deemed-Fake.html

“Is This Crystal Skull Really Ancient?” Smithsonian.com, Smithsonian Institution, www.smithsonianmag.com/videos/category/history/a-real-crystal-skull/.

“The Smithsonian Skull .” Chemical and Engineering News , https://cen.acs.org/articles/91/i9/Crystal-Skulls-Deemed-Fake.html

Additional Content
https://anthropology.si.edu/crystal_skulls/
http://www.britishmuseum.org/research/news/studying_the_crystal_skull.aspx