Originally, deme G had a population size of 1963, which grew to 4561 around 7553.0652 generations ago and has not changed since.
time_units: generations
demes:
  - name: G
    start_time: .inf
    epochs:
      - start_size: 1963
        end_time: 7553.0652
      - start_size: 4561
        end_time: 0