my teacher says her dog wakes up at early so does the dog have an internal body clock?

Question: my teacher says her dog wakes up at early so does the dog have an internal body clock?
- Keywords:
  animal,
  body clock,
  dog,
  internal,
  sleep,
  sleep pattern,
  wake up
Asked by nida27 to Indi, Jarv, John, Ken, Vicky on 15 Mar 2012.
- Indi Ghangrekar answered on 15 Mar 2012:
  
  Yep, sure does! Lots of organisms bacteria, fish, plants, mammals, insects, reptiles, amphibians – I would say almost all, have a body clock mechanism!

Question: my teacher says her dog wakes up at early so does the dog have an internal body clock?