A study finds that some dogs are happy but others are unhappy.Have a look at the study.First let the dogs know there are two bowls in the room. One is full of food on the one side, while theother is empty on the other side. Then let the dogs come to the bowls. The happy ones run to the bowl withfood very quickly, but the unhappy ones walk to the bowl very slowlyWhen they see the bowl is half full, the happy ones are very calm and they are sure theirowners must come back。 But the unhappy ones are more likely to worry, bark and misbehave(行为失常)About half of the dogs are unhappy ones. Their owners should take them to the vets to get checkedover and take good care of them.