time_units: generations
demes:
- name: deme1
  start_time: .inf
  epochs:
  - {end_size: 1, end_time: 0, start_size: 1}
- name: deme2
  start_time: .inf
  epochs:
  - {end_size: 10.0, end_time: 0, start_size: 10.0}
- name: deme3
  start_time: .inf
  epochs:
  - {end_size: 20.0, end_time: 0, start_size: 20.0}
migrations: []