Science fiction often portrays deadly organisms emerging from melting ice and wreaking havoc on unsuspecting humans. While these tales may seem far-fetched, the reality is that ancient pathogens frozen in glaciers, ice caps, and permafrost could indeed pose a threat to modern ecosystems. Examples of revived bacteria and viruses from ancient ice cores and permafrost have already been documented.
With Earth’s climate warming rapidly, especially in colder regions like the Arctic, the release of microorganisms from melting ice is increasing. It is estimated that four sextillion microorganisms are released each year, equivalent to the estimated number of stars in the universe. However, despite this massive release of microorganisms, including potential pathogens, the risk they pose to modern ecosystems remains unknown.
A new study published in PLOS Computational Biology aimed to calculate the ecological risks associated with the release of ancient viruses. Using simulations, the researchers found that just 1% of simulated releases of a single dormant pathogen could cause significant environmental damage and widespread loss of host organisms globally.
Using a software called Avida, the researchers simulated the release of ancient pathogens into modern biological communities. They measured the impacts on host bacteria diversity and found that invading pathogens often survived and evolved in the simulated modern world. In some cases, the invading pathogen became dominant and caused losses to host diversity. In the worst-case scenario, the invasion reduced the size of the host community by 30%.
While the risk from a small fraction of pathogens may seem insignificant, it is important to consider the sheer number of ancient microbes being released in the real world. Such outbreaks represent a substantial danger. These findings suggest that the threat of ancient pathogens becoming established and degrading host communities is not just science fiction but a potential driver of ecological change.
The study also highlights the potential risk to humans, as pathogens transmitted from animal hosts have caused notable diseases like SARS-CoV-2, Ebola, and HIV. It is plausible that a once ice-bound virus could enter the human population through a zoonotic pathway. Therefore, understanding and preparing for the potential risks posed by melting ice and ancient pathogens is crucial.
In conclusion, the release of ancient pathogens from melting ice is a real and significant concern. While the likelihood of catastrophic extinctions may be low, it is important to acknowledge and prepare for this unpredictable threat. The risks posed by pathogens should not be underestimated, even if they are microscopic and far from the giant flesh-eating bugs depicted in science fiction films.