New Delhi: Climate change is not only damaging Arctic infrastructure and accelerating greenhouse gas emissions but also erasing one of Earth’s most valuable archives of ancient life, according to a new study published in Nature Communications.
Researchers say Arctic permafrost preserves an extraordinary record of past ecosystems, containing ancient DNA, RNA, proteins and other biological material that has remained frozen for thousands to hundreds of thousands of years. However, rising temperatures are causing these frozen records to degrade before they can be fully studied.
The study conducted in Canada Yukon region, recovered DNA from Arctic ground squirrel droppings preserved in permafrost dating from about 14,000 to 700,000 years ago. The samples revealed the plants the squirrels consumed, parasites they carried, and traces of larger Ice Age animals such as mammoths, horses and bison, providing a detailed snapshot of long-lost ecosystems.
Scientists say Arctic permafrost acts as a unique molecular archive because freezing temperatures, darkness and low oxygen prevent biological material from decomposing. Advances in DNA sequencing now allow researchers to reconstruct ancient genomes and entire ecosystems from tiny fragments of genetic material.
Previous research on the same frozen deposits also uncovered 30,000 year old antibiotic resistance genes, demonstrating that resistance to certain antibiotics existed long before modern medicine and highlighting the potential of permafrost to reveal insights into microbial evolution and future drug discovery.
Researchers warn that warming permafrost is accelerating microbial activity and decomposition, causing irreplaceable biological records to deteriorate. Once thawed, exposure to oxygen, water and microbes rapidly breaks down the preserved material.
The scientists have called for greater efforts to collect and preserve frozen sediment samples in specialised archives while they remain intact. They emphasise that the long term solution is reducing greenhouse gas emissions to slow Arctic warming, as continued climate change could permanently erase invaluable evidence of Earth’s environmental and evolutionary history.