Estimating biodiversity across the tree of life on Mount Everest's southern flank with environmental DNA

Elsevier, iScience, Volume 25, 16 September 2022
Lim M.C.W., Seimon A., Nightingale B., Xu C.C.Y., Halloy S.R.P., Solon A.J. et al.

Species composition in high-alpine ecosystems is a useful indicator for monitoring climatic and environmental changes at the upper limits of habitable environments. We used environmental DNA (eDNA) analysis to document the breadth of high-alpine biodiversity present on Earth's highest mountain, Mt. Everest (8,849 m a.s.l.) in Nepal's Khumbu region. In April-May 2019, we collected eDNA from ten ponds and streams between 4,500 m and 5,500 m. Using multiple sequencing and bioinformatic approaches, we identified taxa from 36 phyla and 187 potential orders across the Tree of Life in Mt. Everest's high-alpine and aeolian ecosystem. These organisms, all recorded above 4,500 m—an elevational belt comprising <3% of Earth's land surface—represents ∼16% of global taxonomic order estimates. Our eDNA inventory will aid future high-Himalayan biomonitoring and retrospective molecular studies to assess changes over time as climate-driven warming, glacial melt, and anthropogenic influences reshape this rapidly transforming world-renowned ecosystem.