Originally, deme G had a population size of 9591, which changed to 2120 around 4585.8026 generations ago and has not changed since.
time_units: generations
demes:
  - name: G
    start_time: .inf
    epochs:
      - start_size: 9591
        end_time: 4585.8026
      - start_size: 2120
        end_time: 0