Nav: Home

Ancient oyster shells provide historical insights

July 14, 2020

An interdisciplinary team of scientists studying thousands of oyster shells along the Georgia coast, some as old as 4,500 years, has published new insights into how Native Americans sustained oyster harvests for thousands of years, observations that may lead to better management practices of oyster reefs today.

Their study, led by University of Georgia archaeologist Victor Thompson, was published July 10 in the journal Science Advances.

The new research argues that understanding the long-term stability of coastal ecosystems requires documenting past and present conditions of such environments, as well as considering their future. The findings highlight a remarkable stability of oyster reefs prior to the 20th century and have implications for oyster-reef restoration by serving as a guide for the selection of suitable oyster restoration sites in the future.

Shellfish, such as oysters, have long been a food staple for human populations around the world, including Native American communities along the coast of the southeastern United States. The eastern oyster Crassostrea virginica is a species studied frequently by biologists and marine ecologists because of the central role the species plays in coastal ecosystems.

Oyster reefs are a keystone species that provide critical habitats for other estuarine organisms. Oyster populations, however, have dramatically declined worldwide over the last 100 years due to overexploitation, climate change and habitat degradation.

"Oyster reefs were an integral part of the Native American landscape and our study shows that their sustainability over long periods of time was likely due to the sophisticated cultural systems that governed harvesting practices," said Thompson, professor of anthropology in the Franklin College of Arts and Sciences and director of the UGA Laboratory of Archaeology.

According to Thompson, prior models used by archaeologists have not adequately accounted for the role Indigenous people had not only sustaining ecosystems, but also enhancing biodiversity.

"Our research shows that harvesting was done likely with an aim towards sustainability by Native American communities," he said. "Work here along the Georgia coast, along with colleagues working in the Pacific and in Amazonia, indicates that Indigenous peoples had a wealth of traditional ecological knowledge regarding these landscapes and actively managed them for thousands of years."

Changes in oyster shell size and abundance is widely used to examine human population pressures and the health of oyster reefs. The researchers measured nearly 40,000 oyster shells from 15 Late Archaic (4500 - 3500 years Before Present) through Mississippian (1150 - 370 years BP) period archaeological sites situated along the South Atlantic coast of the United States to provide a long-term record of oyster harvesting practices and to document oyster abundance and size across time.

The new findings show an increase in oyster size throughout time and a nonrandom pattern in their distributions across archaeological sites up and down the coastline that the authors believe is related to the varying environmental conditions found in different areas.

When the researchers compared their work to maps of the 19th-century oyster reef distributions, they found that the two were highly correlated. All of the data on oyster size and reef size suggested there was considerable stability in oyster productivity over time, even if some reefs were not quite as productive as others. This overall productivity changed, however, in the early 1900s when industrial oyster canning devastated the reefs, leaving only a small percent of the reefs viable today.

"This work, which was partially supported by the Georgia Coastal Ecosystems Long Term Ecological Research project, demonstrates the importance of understanding the role that humans play in shaping the landscape, and that is something that is not always appreciated in ecological studies," said Merryl Alber, professor and director of the UGA Marine Institute on Sapelo Island, a site of excavations for this study.
-end-
The Georgia Coastal Ecosystems research project, established in 2000 with a grant from the National Science Foundation and renewed for the third time in 2019, studies long-term change in coastal ecosystems such as the saltwater marshes that characterize Georgia's coastline.

University of Georgia

Related Climate Change Articles:

Mysterious climate change
New research findings underline the crucial role that sea ice throughout the Southern Ocean played for atmospheric CO2 in times of rapid climate change in the past.
Mapping the path of climate change
Predicting a major transition, such as climate change, is extremely difficult, but the probabilistic framework developed by the authors is the first step in identifying the path between a shift in two environmental states.
Small change for climate change: Time to increase research funding to save the world
A new study shows that there is a huge disproportion in the level of funding for social science research into the greatest challenge in combating global warming -- how to get individuals and societies to overcome ingrained human habits to make the changes necessary to mitigate climate change.
Sub-national 'climate clubs' could offer key to combating climate change
'Climate clubs' offering membership for sub-national states, in addition to just countries, could speed up progress towards a globally harmonized climate change policy, which in turn offers a way to achieve stronger climate policies in all countries.
Review of Chinese atmospheric science research over the past 70 years: Climate and climate change
Over the past 70 years since the foundation of the People's Republic of China, Chinese scientists have made great contributions to various fields in the research of atmospheric sciences, which attracted worldwide attention.
A CERN for climate change
In a Perspective article appearing in this week's Proceedings of the National Academy of Sciences, Tim Palmer (Oxford University), and Bjorn Stevens (Max Planck Society), critically reflect on the present state of Earth system modelling.
Fairy-wrens change breeding habits to cope with climate change
Warmer temperatures linked to climate change are having a big impact on the breeding habits of one of Australia's most recognisable bird species, according to researchers at The Australian National University (ANU).
Believing in climate change doesn't mean you are preparing for climate change, study finds
Notre Dame researchers found that although coastal homeowners may perceive a worsening of climate change-related hazards, these attitudes are largely unrelated to a homeowner's expectations of actual home damage.
Older forests resist change -- climate change, that is
Older forests in eastern North America are less vulnerable to climate change than younger forests, particularly for carbon storage, timber production, and biodiversity, new research finds.
Could climate change cause infertility?
A number of plant and animal species could find it increasingly difficult to reproduce if climate change worsens and global temperatures become more extreme -- a stark warning highlighted by new scientific research.
More Climate Change News and Climate Change Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: The Power Of Spaces
How do spaces shape the human experience? In what ways do our rooms, homes, and buildings give us meaning and purpose? This hour, TED speakers explore the power of the spaces we make and inhabit. Guests include architect Michael Murphy, musician David Byrne, artist Es Devlin, and architect Siamak Hariri.
Now Playing: Science for the People

#576 Science Communication in Creative Places
When you think of science communication, you might think of TED talks or museum talks or video talks, or... people giving lectures. It's a lot of people talking. But there's more to sci comm than that. This week host Bethany Brookshire talks to three people who have looked at science communication in places you might not expect it. We'll speak with Mauna Dasari, a graduate student at Notre Dame, about making mammals into a March Madness match. We'll talk with Sarah Garner, director of the Pathologists Assistant Program at Tulane University School of Medicine, who takes pathology instruction out of...
Now Playing: Radiolab

What If?
There's plenty of speculation about what Donald Trump might do in the wake of the election. Would he dispute the results if he loses? Would he simply refuse to leave office, or even try to use the military to maintain control? Last summer, Rosa Brooks got together a team of experts and political operatives from both sides of the aisle to ask a slightly different question. Rather than arguing about whether he'd do those things, they dug into what exactly would happen if he did. Part war game part choose your own adventure, Rosa's Transition Integrity Project doesn't give us any predictions, and it isn't a referendum on Trump. Instead, it's a deeply illuminating stress test on our laws, our institutions, and on the commitment to democracy written into the constitution. This episode was reported by Bethel Habte, with help from Tracie Hunte, and produced by Bethel Habte. Jeremy Bloom provided original music. Support Radiolab by becoming a member today at Radiolab.org/donate.     You can read The Transition Integrity Project's report here.