Deme G maintained a population of 4878 until there was a shift 4954.4 generations ago that changed its numbers to 7738, a figure that has remained the same since.
time_units: generations
demes:
  - name: G
    start_time: .inf
    epochs:
      - start_size: 4878
        end_time: 4954.4
      - start_size: 7738
        end_time: 0