Why do elephants pule behind their jaw when they are anxious or annyoed?

Question: Why do elephants pule behind their jaw when they are anxious or annyoed?
- Keywords:
  elephant,
  emotion
Asked by seas122 to Charlotte, Jo, Kevin, Louise, Valeria on 16 Jun 2012.
- Joanna Cruden answered on 16 Jun 2012:
  
  I don’t know much about elephants but I would guess that it is to do with increased heart rate, arterial tension which may cause a pulse when the animal is angry in a similar way that it does with humans when some of them get angry

Question: Why do elephants pule behind their jaw when they are anxious or annyoed?