Using a process called paleo-experimental evolution, a 500-million-year-old gene from bacteria has been resurrected and inserted into modern-day Escherichia coli (E. coli) bacteria, giving scientists a front row seat to observe evolution in action.

The bacterium, which has been growing for more than 1,000 generations, is a close step to rewinding and replaying the molecular “tape” of life.

The ability to observe an ancient gene in a modern organism as it evolves within a modern cell allows the ability to see whether the evolutionary trajectory once taken will repeat itself or whether a life will adapt following a different path.