Individual #Oligocene_epoch__Oligocene  from 25 million to 40 million years ago; appearance of sabertoothed cats
  instance of:  #epoch
  part of:  #Tertiary_period__Tertiary  from 2 million to 63 million years ago
     part of:  #Cenozoic_era__Cenozoic__Age_of_Mammals  approximately the last 63 million years

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