Until 4514.0 generations ago, the population of deme N was 6312. At that point, it changed to 8353, where it has stayed up to now.
time_units: generations
demes:
  - name: N
    start_time: .inf
    epochs:
      - start_size: 6312
        end_time: 4514.0
      - start_size: 8353
        end_time: 0