In a recent study, DNA found in the meltwater from the world’s highest peak revealed a treasure trove of biodiversity.
The Himalayan snowcock is one of the species recorded on Mount Everest.
In the spring of 2019, Tracie Seimon would lie awake listening to the deep rumbling of ice cracking. The glacier where she slept at the base of Mount Everest was shifting beneath her tent.
Seimon, a molecular biologist with the Wildlife Conservation Society in New York, spent three weeks traversing the Nepali glacier. She hoped to capture a snapshot of biodiversity in one of the planet’s most extreme environments: a mountain over eight kilometers high, prone to sub-zero temperatures, limited oxygen, and fierce storms.
But despite its inhospitable nature, the world’s highest peak is teeming with life. Seimon and her team found 16% of Earth’s taxonomic orders (a classification that includes families, genera, and species) just on the south face of Everest. They recently published their findings in the journal iScience.
“You feel very small venturing into the mountains,” says Seimon. “It’s incredible.”
She adds that most trekkers are unaware of the abundant life surrounding them.
The Everest Base Camp sits atop the Khumbu Glacier, where Seimon’s team lived in tents alongside climbers seeking the summit. The colorful cluster of tents welcomes around 40,000 people each year, which can be detrimental to the surrounding ecosystem, says co-author Anton Seimon, an atmospheric scientist at Appalachian State University and a National Geographic Explorer.
In addition to foot traffic, climate change is also affecting the mountain, so researchers wanted to establish a baseline for its biodiversity. Understanding what life exists on Everest now will help scientists track changes in the future.
“It’s been a fascinating experience and privilege to be part of the effort,” says Anton, who is married to Seimon.
Finding Life in Meltwater
The team went to Mount Everest as part of the Perpetual Planet initiative, a research collaboration between the National Geographic Society and Rolex that studies Earth’s forests, oceans, and mountains. Besides studying biodiversity, other teams installed new weather stations and collected ice cores. Like most Everest researchers and trekkers, their work was supported by a team of Sherpas who transported equipment, maintained the camp, and guided scientists up the mountain.
Seimon’s key to finding signs of life was collecting DNA in thawed water puddles. All living organisms typically shed environmental DNA, or eDNA, into the surrounding air, water, and soil. Scientists can match an unknown snippet of eDNA to existing data to determine which organism it comes from, much like a library’s barcode provides information about a book.
The researchers focused on the highest ponds and streams on Everest, located between 4,480 and 5,486 meters in the alpine zone and beyond. In total, the team collected just over 19 liters of water from ten bodies of water in the Khumbu region. From there, they identified 187 different orders, one-sixth of all taxonomic orders on Earth.
A taxonomic order is a classification that helps scientists trace the relationship of individual organisms. For example, humans are classified as Homo (genus) and sapiens (species), but they also belong to the family Hominidae and the order Primates, which also includes lemurs, monkeys, and apes.
In some cases, the researchers were able to identify organisms more specifically down to the genus level. However, since there is so little data on Mount Everest inhabitants, there was often not enough information to cross-reference the DNA in such detail.
Seimon says that Mount Everest and other high mountain ecosystems are under-studied.
“The total land mass above 4,480 meters is less than three percent of the Earth’s total land mass,” she says. “Finding as much biodiversity as we did up there was very exciting.”
Delving Deeper into Everest
Among the organisms swimming, flying, and crawling on Everest’s seemingly barren slopes were tardigrades and rotifers, two hardy microscopic creatures that can even survive in the vacuum of space. There were also butterflies, mayflies, and other flying insects, along with various fungi, bacteria, and plants.
“It’s the top of the world, and it’s very inaccessible,” says Kristine Bohmann, a biologist at the University of Copenhagen in Denmark who works with environmental DNA in the air and was not involved in the research. She says the work shows that studying biodiversity doesn’t always require a full team of taxonomists and can sometimes be done more simply and efficiently, even in challenging environments.
Further research will help create a better record of diversity on Mount Everest and document specific organisms. Conducting future studies at different times of the year may bring even more biodiversity to light and show which genera and species live on the mountain under varying weather conditions.
Once a baseline is established, one of Seimon’s next goals is to compare the data with future samplings, especially to document the effects of climate change on Everest’s biodiversity. Her work can help inform future studies, paving the way for more research on the world’s rooftop.