For the O deme, the population size remained at 2450 until 8918.565 generations ago, at which point a exponential change took place until 4541.1378 generations for size 5755. Afterward, the population saw an exponential change to 9950 by 3111.0393. From 3111.0393 generations ago to today, there's been a exponential decrease from 9950 to 6598.
time_units: generations
demes:
  - name: O
    start_time: .inf
    epochs:
      - start_size: 2450
        end_time: 8918.565
      - start_size: 2450
        end_size: 5755
        end_time: 4541.1378
        size_function: exponential
      - start_size: 5755
        end_time: 3111.0393
        end_size: 9950
        size_function: exponential
      - end_time: 0
        start_size: 9950
        end_size: 6598
        size_function: exponential