Nothing to be concerned about
Scientists resurrected a microscopic worm that had been living in the Siberian permafrost for the last 46,000 years in a study that sheds new light on our own evolutionary process.
In a study published in PLOS Genetics, a group of scientists carbon-dated and sequenced the genome of two nematodes – better known as roundworms – revealing they were from the late Pleistocene era.
Nematodes can become extremely inactive, or “enter a state of suspended metabolism”, when surrounded by challenging environmental conditions which is called cryptobiosis.
“This state-transition requires execution of a combination of genetic and biochemical pathways that enable the organism to survive for prolonged periods,” the study findings state.
In 2018, researcher Anastasia Shatilovich came across the two nematodes that were in cryptobiosis in the sub-zero temperatures of the permafrost.
Researchers thawed the worms back to life and out of cryptobiosis so they could analyse what plant materials they had eaten beforehand. The nematodes were thought to be around 46,000 years on.
“Recently, nematode individuals have been reanimated from Siberian permafrost after remaining in cryptobiosis. Preliminary analysis indicates that these nematodes belong to the genera Panagrolaimus and Plectus. Here, we present precise radiocarbon dating indicating that the Panagrolaimus individuals have remained in cryptobiosis since the late Pleistocene (~46,000 years).”
It was thought the worms could only stay in a state of cryptobiosis for just under 40 years.
The latest discovery suggests nematodes can spend millennia in a suspended state.
“Our findings demonstrate that nematodes evolved mechanisms potentially allowing them to suspend life over geological time scales,” the scientists wrote in their paper.
The discovery, the paper suggested, is crucial in order to help scientists understand our own evolutionary process as well as the long-term survival of individual organisms. It may also be the first step in figuring out how science can bring back extinct species.
“Our findings here are important for the understanding of evolutionary processes because generation times could be stretched from days to millennia, and long-term survival of individuals of species can lead to the refoundation of otherwise extinct lineages.”
Read the study here.