The Effects of Volcanic Activity on Societies in the Jama River Valley

Volcanoes can be destructive, but they can also lead to beneficial changes in societies. The Jama-Coaque I peoples lived to the west of the Ecuadorian Andes, which includes more than 30 active volcanoes. After the eruption of Pichincha (Figure 1), one of these volcanoes, the Jama-Coaque I peoples left the Jama River Valley (Coutros 2018). However, the destructive volcanoes did not keep people away from the Jama River Valley forever. The Jama-Coaque II peoples, descendents of Jama-Coaque I, resettled the valley hundreds of years later (Coutros 2018). This cycle of settlement and abandonment of the Jama River Valley began long before the Jama-Coaque I peoples left the valley. Around 1880 B.C., Pichincha erupted and the Valdivian peoples were forced to abandon their thriving farms, and around 467 B.C., the eruption of Pululahua, another volcano in the region, led to the Chorrera peoples leaving the Jama River Valley (Coutros 2018).

Figure 1. Ecuador’s Pichincha volcano.

The volcanic activity of the Ecuadorian Andes led to changes in the Jama-Coaque II peoples who returned to the valley. Previous inhabitants of the Jama River Valley, like the Valdivia and Chorrera cultures, relied on floodplain agriculture, which involves growing crops on river banks. When the river system was clogged by volcanic ash, their crops died. By diversifying their nutrient sources and agricultural techniques, the Jama-Coaque II peoples did not have to rely on floodplain agriculture to survive (Coutros 2018). This illustrates the importance of a society’s ability and willingness to change in order to adapt to a changing environment (O’Donnell 2017). The changes made by the Jama-Coaque II peoples led to their success in surviving in the Jama River Valley (Figure 2).

Figure 2. A map of the Jama River Valley and the Ecuadorian Andes.

Communal storage pits, which were used to store food for more than one household, and increased warfare and raiding suggest the rise of a centralized authority in the Jama-Coaque II communities (Coutros 2018). Communal storage and increased warfare allows the Jama-Coaque II peoples to maintain and protect food reserves. While volcanic activity may have pushed communities out of the Jama River Valley for hundreds of years, it also led to the Jama-Coaque II peoples developing practices that allowed them to thrive in the valley.

Volcanic activity has importance in archaeology beyond studying how it affects various cultures. A dating method used in archaeology involves studying layers of volcanic ash deposits. Tephrochronology is the study of volcanic ash, or tephra, deposits (U.S. Geological Survey 2016). Tephrochronology is a helpful tool in areas like Iceland, where tephrochronology was utilized in a study of human impact on the environment (McGovern et al. 2007). In these situations, the layers of ash deposited by volcano eruptions can help archaeologists date artifacts.

Additional Content

This page explains how the Jama-Coaque culture is known for its ceramic creations and describes a Jama-Coaque sculpture: https://www.metmuseum.org/art/collection/search/314183

An article about how early humans may have survived the eruption of a volcano named Toba: https://www.sciencemag.org/news/2018/03/how-ancient-humans-survived-global-volcanic-winter-massive-eruption

References Cited

Coutros, Peter

2018 How Volcanoes Destroy and Nurture Societies. Electronic document, https://www.sapiens.org/column/off-the-map/volcanic-archaeology-pichincha-volcano/, accessed November 8, 2018.

 

McGovern, Thomas H., Orri Vésteinsson, Adolf Fridriksson, Mike Church, Ian Lawson, Ian A. Simpson, Arni Einarsson, Andy Dugmore, Gordon Cook, Sophia Perdikaris, Kevin J. Edwards, Amanda M. Thomson, W. Paul Adderley, Anthony Newton, Gavin Lucas, Ragnar Edvardsson, Oscar Aldred, and Elaine Dunbar

2007 Landscapes of Settlement in Northern Iceland: Historical Ecology of Human Impact and Climate Fluctuation on the Millennial Scale. American Anthropologist 109(1):27-51. DOI: 10.1525/AA.2007.109.1.27, accessed November 9, 2018.

 

O’Donnell, Jim

2017 How Vulnerable Are We to Collapse? Electronic document, https://www.sapiens.org/archaeology/hohokam-mimbres-collapse/?utm_content=buffer75cc7&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer, accessed November 9, 2018.

 

U.S. Geological Survey

2016 USGS Tephrochronology (Tephra) Project. Electronic document, https://geomaps.wr.usgs.gov/tephra/index.htm, accessed November 9, 2018.

 

Image Sources

Coutros, Peter

2018 How Volcanoes Destroy and Nurture Societies. Electronic document, https://www.sapiens.org/column/off-the-map/volcanic-archaeology-pichincha-volcano/, accessed November 9, 2018.

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.