 An iconic contemporary example of microbial modelling is Richard Lenski’s long-term evolution experiment (Fox &amp; Lenski 2015). Lenski’s group used a single ancestral genome of E. coli to found twelve initially genetically identical populations in identical flask environments. They began propagating the populations, by transferring a population sample from a well-mixed flask to a fresh flask (to replenish their resources) every 24 hours. Lenski’s group began this experiment in 1988 and it is still going today, which in early 2020 means more than 70,000 generations of microbial evolution have  occurred.[8]  These numbers are due to E. coli populations regenerating just over six times per day, with resource constraints keeping this number steady.