The study of ancient viruses archived in the Guliya Glacier ice core is the result of a decade-long interdisciplinary collaboration and builds upon a 2015 U.S.-China joint Guliya Glacier expedition that was spearheaded by the Byrd Polar and Climate Research Center at The Ohio State University (OSU) and the Institute of Tibetan Plateau Research at the Chinese Academy of Sciences1. The collaboration was led by Dr. Lonnie Thompson in the U.S. and Dr. Tandong Yao in China, who have been partners in scientific research in glaciology and climate change for over 40 years.
Lonnie G. Thompson (right) and Tandong Yao (left) measuring the Guliya ice core section. Photo: Jane Qui
During the expedition, a ~60-person team worked for over two months on the Guliya Glacier at 6,200 to 6700 meters (20,341 to 21,981 feet) above sea level, and successfully retrieved several ice cores, including one reaching the glacier’s bedrock, ~310 meters deep2. Half of the ice core sections are preserved in the Institute of Tibetan Plateau Research in China and the other half were transported from the field to Lhasa, and then to Beijing, Chicago, and are preserved in freezers at The Ohio State University. These cores were collected to study paleoclimates; the layers of ice, accumulated over hundreds of thousands of years, contain invaluable records of past climates, offering insights into the evolution of Earth’s climate over time.
Drilling on the Guliya Glacier. Photo courtesy of Lonnie Thompson.
However, the previous year, Drs. Lonnie Thompson and Ellen Mosley-Thompson had attended the Ohio State Sigma Xi Meeting, and heard Dr. James Van Etten (from the University of Nebraska-Lincoln) speak about chloroviruses, and talked with him afterward about the possibility of studying ancient viruses in ice cores.
A year later, when James’s fellow virologist Matthew Sullivan — known for rigorous low-biomass environmental viral work — was recruited to OSU, he recognized the opportunity to turn that conversation into action and suggested a meeting. A fellow new faculty recruit Virginia Rich — a climate change microbial ecologist — was a fan of the Thompsons from Discovery channel shows and joined the meeting. Our five-person group had a riveting cross-disciplinary conversation at the Byrd Polar and Climate Research Center (BPCRC), a conversation that expanded the focus from solely studying climate from the ice cores to investigating the ancient microbial life, including viruses, that had been preserved in the ice alongside the paleoclimates for many thousands of years.
A catalyst was needed to move these ideas into active research. In 2016, Dr. Zhi-Ping Zhong, while he was preparing to defend his Ph.D. in Microbiology from the Institute of Microbiology at the Chinese Academy of Sciences, was awarded a highly competitive BPCRC Postdoctoral Fellowship to investigate the ancient microbes and viruses in ice cores. He was co-supervised by all five of them.
The glacier microbiology project, however, came with significant challenges. Ice cores inherently contain very low biomass and have very limited materials available for microbial studies, making the detection and analysis of microbes and viruses extremely difficult. We had to work with ultra-low inputs, few samples, and no replication opportunities due to the scarcity of ice materials. Zhi-Ping and colleagues dedicated years to leading the effort to establish clean pipelines for sampling and analyzing the tiny amounts of microbial and viral material present in the ice cores3,4. It was crucial to ensure that the viruses and microbes obtained were genuinely from the ice cores and not contaminants. These rigorous efforts generated the publication of the first genomes and communities of ancient viruses preserved in glacier ice3.
A meeting of our interdisciplinary team in 2018 (from left to right: Matthew Sullivan, Virginia Rich, Zhi-Ping Zhong, Lonnie Thompson, Ellen Mosley-Thompson, James Van Etten, and Yueh-Fen Li). Photo: Matthew Sullivan.
In addition to the methodological challenges, the team faced another significant hurdle. Studying ancient viruses preserved in ice was novel and considered risky which made securing traditional scientific funding challenging, with, unfortunately, seven times unsuccessful applications from national funding agencies in the past several years. Therefore we had to utilize internal resources, including the Byrd Postdoc Fellowship, start-up funds from Drs. Sullivan and Rich, and funding from the Third Pole Office, to cover Zhi-Ping’s salary and procure the necessary materials and supplies to initiate the project. Despite these financial constraints, the team pressed on, driven by curiosity and the belief that these ancient viruses could provide new insights into Earth’s history and the evolution of life. We later received sequencing support from the U.S. Department of Energy’s Joint Genome Institute, and in 2022, we were fortunate to secure funding from the Heising-Simons Foundation to study glacier microbes in the Andes.
The initial lack of financial support delayed the overall progress of this project, including manuscript preparation. The first draft of this paper was completed in 2022, but its submission was delayed until early 2024 since all co-authors were not paid for this project. After years of persistence, we successfully extracted and sequenced approximately 1,700 genomes of ~species-level virus operational taxonomic units from the ice core, expanding the known collection of glacier-preserved ancient viruses more than 50-fold. Our findings revealed that these viruses could be linked to co-archived climate conditions, including the cold-to-warm fluctuations over the past 41,000 years. This finding opened a new window into understanding how viruses have changed over tens of thousands of years and how they interacted with the environment during different climatic conditions. The connection between ancient viruses and paleoclimate data provided a unique perspective on the co-evolution of life and Earth’s climate, offering new avenues for research in both virology and climate science. This work was published today in Nature Geoscience.
Left, this study expanded the known collection of glacier-preserved ancient viruses from 33 to 1,705 ~species-level viral operational taxonomic units (vOTUs); Right, viral communities significantly differed between cold and warm periods during the past 41,000 years. These plots are from Fig. 2 of the paper just published in Nature Geoscience.
This “behind the paper” story emphasizes the power of interdisciplinary collaboration and the importance of perseverance in scientific research. The nearly decade-long journey from the initial ice core sampling to the discovery of ancient viruses was fraught with methodological and funding challenges. However, it was the collaborative spirit and shared determination of researchers from diverse fields that ultimately made this interesting work possible. Through the dedication of our team, this study has not only expanded our understanding of ancient viruses but also highlighted the intricate connections between life and the changing climate over tens of millennia.
References:
Thompson, L. G., Yao, T. D., Davis, M. E., Mosley-Thompson, E., Synal, H. A., Wu, G., Bolzan, J. F., Kutuzov, S., Beaudon, E., Sierra-Hernández, M. R. & Beer, J. Ice core evidence for an orbital-scale climate transition on the Northwest Tibetan Plateau. Quaternary Science Reviews 324, 108443 (2024).
Thompson, L. G., Yao, T., Davis, M. E., Mosley-Thompson, E., Wu, G., Porter, S. E., Xu, B., Lin, P. N., Wang, N., Beaudon, E., Duan, K., Sierra-Hernández, M. R. & Kenny, D. V. Ice core records of climate variability on the Third Pole with emphasis on the Guliya ice cap, western Kunlun Mountains. Quaternary Science Reviews 188, 1–14 (2018).
Zhong, Z. P., Tian, F., Roux, S., Gazitúa, M. C., Solonenko, N. E., Li, Y. F., Davis, M. E., Van Etten, J. L., Mosley-Thompson, E., Rich, V. I., Sullivan, M. B. & Thompson, L. G. Glacier ice archives nearly 15,000-year-old microbes and phages. Microbiome 9, 160 (2021).
Zhong, Z. P., Solonenko, N. E., Gazitúa, M. C., Kenny, D. V., Mosley-Thompson, E., Rich, V. I., Van Etten, J. L., Thompson, L. G. & Sullivan, M. B. Clean Low-Biomass Procedures and Their Application to Ancient Ice Core Microorganisms. Frontiers in Microbiology 9, 1094 (2018).