Corn, Cultivation and Native Americans

Have you ever heard of “Indian Corn”? All corn is “Indian Corn”. The Native Americans discovered a way to make the corn they had more edible and bountiful, to feed a vast majority economically. Corn started out as a black big, almost pointy and hard kernels called Teosinte. (NativeTech)

This is the Teosinte plant and what Corn looks like now.

Photo Credit: Nicolle Rager Fuller, National Science Foundation

According to the National Science Foundation, in 2005, a scientist in California, Brandon Gaut, helped to make this process more visible by recreating it. He did exactly what the Native Americans did around 10,000 years ago. The scientists took a Teosinte plant, which was only 2-3 inches long and produced about 5 to 12 kernels, which were very hard and mostly for animals to eat. When early botanist found this plant, the scientists quickly dismissed how it could be related to modern corn. Especially when our modern corn is about 12 inches long, and 500 or more kernels. (National Science Foundation, 2005)

Here is a chart of the corn broken down to show the differences. The picture has a chart at the bottom that describes it in scientific terms. The first photo is what we know Maize (corn) to be today. The picture (B) is the grass seed Teosinte ear that has the rachis internode (in) and glume (gl) labelled. The picture ( C) is one of the first cultivations of maize and teosinte. The picture (d) is the actual closeup of the teosinte fruitcase. The picture (e) is a closeup of the cultivation between the maize and the teosinte. The next three pictures at the bottom of the chart (f,g,h), show us what the tesonite glumes and internodes look like in the corn after all the cultivations.

Wang, H.H., Nussbaum-Wagler, T., Li, B., Zhao, Q., Vigouroux, Y., Faller, M., Bomblies, K., Lukens, L., & Doebley, J. (2005). The origin of the naked grains of maize. Nature, 436, 714-719.

Although scientists cannot say how long this cultivation process took. There is some archaeological evidence about how the corn plant completely lost its genetic diversity, which would mean a domestication event. The scientists from the National Science Foundation, believe that it took around 3,500 teosinte plants to create the modern corn.  They figured out from this experiment that it took about 1,000 genes from the Teosinte plant to create the corn. (National Science Foundation, 2005)  During this cultivation process, corn lost its survival ability in the wild.

The cultivation process softened the kernel up and infused it into the cob more. The new corn gained larger ears with more rows of soft kernels. (NativeTech) There is some archaeology that shows this cultivation happened about 6,000 years ago. Archaeology has shown that Argiculture is around 9,000 – 10,000 years old. Archaeologists have found the domestication event of corn to be between 6,000 and 10,000 years old in central Mexico. (NativeTech)

Corn found in Storage Pit

Image Credit:
Wendy and Michael Scullin
UI-OSA Photo Archives

Native Americans made over 250 different kinds of corn, all different colors. (Hilarie, Larry, 1)Maybe these different kinds of corn are just what happened during different cultivations? Did the Natives like them enough to eat? 

Further Reading

Follow the “Three Sisters Method” for planting

https://homeguides.sfgate.com/native-american-method-growing-corn-69787.html

WOW! You can eat the colored “Indian Corn”

http://eatyourwayclean.com/can-you-eat-indian-corn-yes-and-heres-how/

“Indian Corn and edible?”

https://recipes.howstuffworks.com/everything-about-indian-corn.htm

The Domestication of Species and the Effect on Human Life

A crucial part of human history is the development of taming animals to help in daily life, rather than as prey to be hunted or a predator to be avoided. While the topic is not heavily focused on, domestication of animals was just as important as the domestication and farming of plants, because the animals were needed to be able to work the land and were a more reliable source of food than the harvest that may not come.

An estimated timeline of animal domestication
Saey, Tina Hesman. “DNA Evidence Is Rewriting Domestication Origin Stories.” Science News, Science News, 2 Aug. 2018, www.sciencenews.org/article/dna-evidence-rewriting-domestication-origin-stories

Domestication happened at different points in all corners of the world, but animals were all domesticated for a reason, even if that is not their purpose now. Dogs were domesticated to assist in hunting, oxen to pull heavy loads, and farm animals like cows, horses, goats, and sheep for food and milk. While some roles are the same, dogs are no longer primarily used for hunting, horses developed into a means of transportation, and goats have recently been used to eat unwanted plants! Why wasn’t every animal domesticated? The animals that were domesticated usually had flexible diets that didn’t require much work on the human’s part, manageable temperaments, changeable social hierarchy, and would be easily bred in captivity. For example, it wouldn’t be very helpful to domesticate meerkats who have a strict social hierarchy and a specific diet along with a lack of purpose under human control.

The evolution of cattle domestication
“Domesticated Animals.” Archäologisches Freilichtmuseum Oerlinghausen, Archaeological Open-Air Museum Oerlinghausen, afm-oerlinghausen.de/en/afm-rundgang-en/steinzeit-en/jungsteinzeit-en/haustiere-en#prettyPhoto.

Domesticating a species involves human interference in the animals’ breeding patterns. Dogs were domesticated from wolves by selecting the wolf pups that were likely the least aggressive, most obedient, had smaller jaws, or a certain coloring depending on the culture that was domesticating them. This select breading has created the entirely new species of dog, separate from wolf. Domestication also affects the animals brought into human life. Archeologists can usually tell if certain animals are domesticated based on their bones Domesticated horses and cattle used to pull heavily loads for farm work often have osteoarthritis or leg strain that would not be there otherwise.

Animal domestication changed a great deal of human society. It allowed for more permanent settlement as cattle provided a reliable food and supply source. With settlement and supplies came population growth and density and a development of communities that worked to provide everything needed for the people around, even if they weren’t of direct relation as was the previous custom. A downside to domestication was the spread of diseases between humans and animals that would have otherwise jumped between species. Pig flu and transfer of parasites are just a few examples of humans and animals getting a little too close. But without domestication humans may well still be wandering hunter-gatherers.

 

Further Reading:

History of the Domestication of Animals

http://www.historyworld.net/wrldhis/PlainTextHistories.asp?historyid=ab57

Domestication

https://www.britannica.com/science/domestication

 

References:

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

“Domesticated Animals.” Archäologisches Freilichtmuseum Oerlinghausen, Archaeological Open-Air Museum Oerlinghausen, afm-oerlinghausen.de/en/afm-rundgang-en/steinzeit-en/jungsteinzeit-en/haustiere-en#prettyPhoto.

Lear, Jessica. “Our Furry Friends: the History of Animal Domestication.” Journal of Young Investigators, 17 Feb. 2012, www.jyi.org/2012-february/2017/9/17/our-furry-friends-the-history-of-animal-domestication.

National Geographic Society. “Domestication.” National Geographic Society, 9 Oct. 2012, www.nationalgeographic.org/encyclopedia/domestication/.

Saey, Tina Hesman. “DNA Evidence Is Rewriting Domestication Origin Stories.” Science News, Science News, 2 Aug. 2018, www.sciencenews.org/article/dna-evidence-rewriting-domestication-origin-stories

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.

 

Deep Sea Excavation and Sample Collection of Plastic Debris

Recent research has shown that deep sea sediments are a likely sink for microplastics. Studies in the Arctic Ocean, the Mediterranean Sea, and the Southwest Indian Ocean show an abundance of plastic debris. Deep-sea coring was used as a method of sampling.

Plastic waste samples taken from the North Pacific

Since plastic is extremely durable, there is difficulty in disposing of the matter, which is why it accumulates in the natural environment. The plastic in the deep sea could have come from a multitude of origins; humans use plastic religiously. We have plastic in our computers, to carry our groceries, and in many other daily objects. Other sources could be fishing waste, shipyards, or municipal drainage systems.

The plastics could have travelled north by way of the ice floes in the Thermohaline Circulation, ocean circulation that is controlled by density differences. Microplastics have a smaller surface area than other plastic debris, so they are less buoyant, which makes them sink faster. Then, the plastics are deposited on the seafloor.

The generation and deposition of plastics in the oceans

Multiple research expeditions collected deep-sea sediment cores from basins, submarine canyons, seamounts (a submarine mountain), and continental slopes (the sea floor before the break of the waves). According to the article, The Deep Sea is a Major Sink for Microplastic Debris, “ten centimetre diameter cores were obtained from megacorers or boxcores that were subsequently subsampled.” Megacorers take wide samples in plastic tubes with a weight and suction system. Boxcorers take 600 millimeter square samples. In another study, scientists took samples by video guided multiple corers, which took eight cores. Multiple corers can take up to twelve undisturbed cores in plastic tubes. Coral specimens from different seamounts were also taken and observed.

The different sampling methods proved to be most explanatory. According to Royal Society Open Science, “275 million metric tons (MT) of plastic waste was generated in 192 coastal countries in 2010, with 4.8 to 12.7 million MT entering the ocean” (Plastic waste inputs from land into the ocean.) The Royal Society Open Science also “confirmed that microplastics were abundant in all 12 sediment samples and all coral samples” and found that microplastics were found on every strata level ranging down to a depth of 3,500 meters. This prevalence of microplastic in all levels of their sampling and in all of the coral types sampled spanning many seas reveals that there is a great deal of plastic in the deep sea.

The increase of plastics in the deeps sea negatively impacts shipping, tourism, and majorly affects wildlife. It affects many marine organisms by being taken in at the lowest level on the food chain. Microplastic “is of particular concern because it can be taken up by a wider range of biota (>172 species) and can be propagated in food webs” (High Quantities of Microplastic in Arctic Deep-Sea Sediments.) One of the most remote places on the earth, the deep Arctic sea, is being polluted by plastic waste. This is important to know and understand so that we can make reparations. Action must be taken to reduce our plastic production.

Links:

https://phys.org/news/2017-08-marine-microplastics-bottom-dweller-bellies.html

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6076259/

 

Citations:

 

Woodall LC et al. 2014 The deep sea is a major sink for microplastic debris.R. Soc. open sci. 1:http://dx.doi.org/10.1098/rsos.140317

 

High Quantities of Microplastic in Arctic Deep-Sea Sediments from the HAUSGARTEN

Observatory Melanie Bergmann, Vanessa Wirzberger, Thomas Krumpen, Claudia

Lorenz, Sebastian Primpke, Mine B. Tekman, and Gunnar Gerdts. Environmental

Science & Technology 2017 51 (19), 11000-11010 DOI: 10.1021/acs.est.7b03331

 

Plastic waste inputs from land into the ocean J. R. Jambeck, R. Geyer, C. Wilcox, T. R. Siegler, Perryman, A. Andrady, R. Narayan, K. L. Law, Science (Washington, DC, U. S.)(2015), 347 (6223) 347 768-771 CODEN: SCIEAS ISSN: 0036-8075

 

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

New York.

 

Getty Images. “Samples of plastic waste level in ocean water taken in the North Pacific.” The

Guardian, Adam Vaughan 2018 Guardian News and Media Limited

https://www.theguardian.com/environment/2014/dec/17/microplastic-deposits-found-deep-in-worlds-oceans-and-seas#img-1

 

“Seafloor Sampling.” Edited by Oceanography Center National, When Did Modern Rates of Sea Level Rise Start? | National Oceanography Centre, 2018, noc.ac.uk/facilities/national-marine-equipment-pool/scientific-engineering/seafloor-sampling.

 

Eunomia, Research and Consulting. Eunomia Marine Litter.

 

Riebeek, Holli. “Paleoclimatology: Explaining the Evidence.” NASA, NASA, 9 May 2006,

earthobservatory.nasa.gov/Features/Paleoclimatology_Evidence.

 

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.

How Global Warming is Affecting the Accuracy of Radiocarbon Dating

Though archaeologists can come up with good guesses about the date of artifacts through different processes, most methods of dating are trumped by a relatively new technique called radiocarbon dating. Developed in 1949, it is considered the most useful way of determining the dates of artifacts for archaeologists.

Radiocarbon dating was discovered when chemist Willard Libby realized radioactive carbon-14 (14C) is made in the Earth’s atmosphere, and then absorbed into plants and entered into the carbon cycle. Since 14C is radioactive, it decays at a relatively quick exponential rate (Figure 1), while non-radioactive carbon (12C) does not. By measuring an artifact’s 14C to 12C ratio, chemists can determine the date of any organic material that was part of the carbon cycle (Bahn and Renfrew 2010:210).

While Libby noted that radiocarbon dating remains effective because the amount of 14C produced in the atmosphere does not vary with time, this may not always be the case.

Fossil fuel emissions have undoubtedly raised the amount of 12C in the atmosphere, with there being an upward trend in in the metric tons of Carbon in the atmosphere since the industrial revolution (Figure 2). CO2 emissions have increased by 90% since 1970 (EPA 2017), and it is therefore important to consider the effects of this new carbon in the atmosphere on radiocarbon dating, the effectiveness of which remains contingent upon the fact that the proportion of 14C in the atmosphere does not vary.

When fossil fuels are released into the atmosphere, they release 12C, and not 14C. This changes the ratio of 12C to 14C, which is what is measured to date artifacts. If the excess C12 in the atmosphere brought about by global warming enters the carbon cycle, the ratio of 12C to 14C increases greatly, making new organic material read as much older (Graven, Heather D. 2015). With an excess of 12C in the atmosphere, new organic materials will have the same 14C : 12C ratio as organic material from 1050.

If humans continue to release carbon into the atmosphere, many methods of radiocarbon dating will no longer be viable, and will not be able to provide absolute dates for artifacts up to 2,000 years old (Graven, Heather D. 2015).

Though there are other methods of dating, radiocarbon is favored, and many methods must be used in tandem to provide the most accurate dates possible (Bahn and Renfrew 2010).

Dating as we know it will change if the carbon being released into the atmosphere cannot be managed.

Figure 1. The carbon cycle and the decay of 14C. Sketch by The University of Waikato

Figure 2. Million Metric Tons of Carbon in the atmosphere vs. year. Graph by Boden, T.A., G. Marland, and R.J. Andres 2017

Works Cited:

Bahn, Paul and Colin Renfrew

2010   Archaeology Essentials. 2nd Edition Thames & Hudson Inc., New York, NY.

 

United States Environmental Protection Agency (EPA)

2017  Global Greenhouse Gas Emissions Data. Electronic document, https://www.epa.gov/ghgemissions/global-greenhouse-gas-emissions-data, accessed September 22nd, 2018

 

Graven, Heather D.

2015  Impact of fossil fuel emissions on atmospheric radiocarbon and various applications of radiocarbon over this century. Electronic document, http://www.pnas.org/content/112/31/9542, accessed September 22nd, 2018

 

Additional Content:

 

“The Future of Radiocarbon Dating”

https://www.naturphilosophie.co.uk/the-future-of-radiocarbon-dating-and-an-overview-of-the-ams-technique/

 

“How Carbon-14 Dating Works”

https://science.howstuffworks.com/environmental/earth/geology/carbon-14.htm

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

Tattoos Across Cultures

Although tattoos were originally thought to have dated back to around 2,000 B.C to ancient Egyptian times, recent archaeological discoveries have carbon-dated tattoos to be approximately 5,200 years old. Due to such discoveries, the certainty of when tattoos first originated has become rather unclear. In Egyptian times, “the distribution of the tattooed dots and small crosses on the lower spine and right knee and ankle joints correspond to areas of strain-induced degeneration, with the suggestion that they may have been applied to alleviate joint pain and were therefore essentially therapeutic” (Lineberry). Archeological studies have shown that ancient Egyptian tattooing was primarily a practice reserved for women. Tattooing was used “during the very difficult time of pregnancy and birth. This is supported by the pattern of distribution, largely around the abdomen, on top of the thighs and the breasts” (Lineberry). It is believed that older Egyptian women would pass this tradition of tattooing down to the younger counterparts. The symbolic value of the tattoo in ancient Egypt differs drastically from Samoan culture and more parallely resembles ancient Japanese culture.  

While tattoos do not date back quite as far in Samoan culture as they do in Egyptian culture, tattooing was a long standing tradition that represented an individual’s rank within the tribe. Tattoos in Samoan culture were most often associated with men; however, “women too endured tattooing, but their patterns were typically smaller” (PBS). The men’s tattoos would, “forever celebrate their endurance and dedication to cultural traditions.”(PBS). Typically, Samoan tattoos started at a man’s mid-torso and extended downwards towards their feet. The process of receiving these tattoos was both an extremely painful and dangerous one. Besides the excessively high risk of infection, the men would experience massive amounts of pain, as the tattoos would typically take up to a year to heal completely. The entire tribe would come together to help support the man who received the tattoo. The tattoos needed to be cleaned daily and the men oftentimes needed help with daily tasks, for even just sitting and walking was rather painful.

While different cultures throughout the world have used tattooing as a way to symbolize their beliefs, it is important to note that although these cultures have tattooing in common, the symbolism behind the practice of tattooing differs from culture to culture. This does that mean that there are no similarities in tattooing practices across cultures. For example, Japan and Egypt both used some tattoos as protective symbols, while Samoa and Japan used certain tattoos to denote an individual’s rank (Kearns). Japan’s tattoo practice incorporates elements of both the Samoan and the Egyptian cultures, but still maintains its own uniqueness (Kearns).

Image result for traditional samoan tattoo

Above is a picture of a traditional Samoan tattoo. One that begins mid-torso and continues downward.

The tattooed right hand of a Chiribaya mummy

Above is a corpse that has been mummified and the tattoos that are showing have been preserved over thousands of years.

Reference List

Kearns, Angel. “Inked and Exiled: A History of Tattooing in Japan.” Bodylore: Gender, Sex, Culture, Folklore, and the Body. February 28 2018. Web. <https://sites.wp.odu.edu/bodylore/2018/02/28/inked-and-exiled-a-history-of-tattooing-in-japan/>.

Lineberry, Cate. “Tattoos: The Ancient and Mysterious History.” Smithsonian.com. January 1 2007. Web. <https://www.smithsonianmag.com/history/tattoos-144038580/>.

PBS. “Skin Stories: The Art and Culture of Polynesian Tattoo.” PBS Thirteen. 2003. Web. <https://www.pbs.org/skinstories/history/>.

 

Additional Content

https://www.pbs.org/skinstories/history/

https://sites.wp.odu.edu/bodylore/2018/02/28/inked-and-exiled-a-history-of-tattooing-in-japan/