|Dogs cry for joy after reuniting with their owners
In English, people say dogs are man's best friends. Dogs and humans have been close for thousands of years. Scientists believe the bond is very deep. They found that dogs cry with joy when they see their owner after being away a long time. The scientists studied 22 dogs. They looked at how the dogs reacted when they saw their owners again. When the dogs saw their owners, they cried. When they saw other people they knew, they didn't cry.