Until a shift occurred 9636.0 generations ago, deme T's population was consistently 8018. Since then, it changed to 3947, a number that has remained unchanged to the current time.
time_units: generations
demes:
  - name: T
    start_time: .inf
    epochs:
      - start_size: 8018
        end_time: 9636.0
      - start_size: 3947
        end_time: 0