ABSTRACT
Survival of microbes in ice implies that ancient genomes are essentially locked in the ice for long periods of time. Once they melt from the ice, if they enter a population of the same species, or if they infect a susceptible host, the ancient genotype can mix with modern genotypes. We have termed this “Genome Recycling.” The first time we found it, it was unexpected. We were attempting to calculate mutation rates over time, based on ice core sections of different ages. Instead we found that there were ancient and modern genotypes mixed in the sections of different ages. This might be a survival strategy for those organisms that can survive long-term freezing, and then revive after thawing. Various genotypes can emerge and mix to increase the chances for survival.
