time_units: generations
demes:
- name: deme2
  start_time: .inf
  epochs:
  - {end_size: 0.5, end_time: 0, start_size: 0.5}
- name: deme1
  start_time: 12.0
  epochs:
  - {end_size: 0.5, end_time: 0, start_size: 0.5}
  ancestors: [deme2]
migrations: []