Until a shift occurred 7177.9 generations ago, deme N's population was consistently 3559. Since then, it grew to 5004, a number that has remained unchanged to the current time.
time_units: generations
demes:
  - name: N
    start_time: .inf
    epochs:
      - start_size: 3559
        end_time: 7177.9
      - start_size: 5004
        end_time: 0