Digital organisms can be traced back to the game Darwin, developed in 1961 at Bell Labs, in which computer programs had to compete with each other by trying to stop others from executing .
In Core War, it turned out that one of the winning strategies was to replicate as fast as possible, which deprived the opponent of all computational resources.
Later, Chris Adami, Titus Brown, and Charles Ofria started developing their Avida system,[2] which was inspired by Tierra but again had some crucial differences.
[4] In 1996, Andy Pargellis created a Tierra-like system called Amoeba that evolved self-replication from a randomly seeded initial condition.
More recently REvoSim - a software package based around binary digital organisms - has allowed evolutionary simulations of large populations that can be run for geological timescales.