Recently，researchers have found that dolphins know their own names much like people.Dolphins talk to one another with whistles（口哨） and calls.Scientists have known that the animals also use unusual whistles to name each other.They had thought that dolphins only heard each other's voices.However，the scientists didn't know that dolphins listen for their names too.
   To test this idea，the researchers caught 14 dolphins and recorded their name calls.The scientists then copied each dolphin's voice.When the changed recordings were played，the dolphins replied strongly to the names of their families and group members.They didn't care about the names of dolphins they did not know.
   Dolphins live in large groups that grow and change.Each dolphin's unusual whistle helps it find a friend or a family member easily，or call for help.Understanding their calls need learning.Most animals don't have this skill except（除了） humans，elephants and bats.
   Elephants，for example，communicate（交流） with sound.Their sounds can be heard by other elephants miles away.Dolphins，too，communicate with each other like this.Elephants also communicate by moving their head，feet and trunk.In much the same way，dolphins communicate by their movements.Touching each other is a way for dolphins to express friendship.Elephants also communicate by their great sense of smell.They can know other elephants by the smells they have in a short time.
   Why do dolphins and elephants share the gift of communication？Scientists think it may be because they are social and smart animals.Both have strong family relationship（关系）.Now，scientists want to know if they also have nicknames.

Social and Smart Animals
Fun（1） facts facts about the animals	Dolphins	● They know their own names. ● They use whistles and calls to talk to（2） others others . ● They reply to their families and group members（3） but but they don't care about the strangers ● It's difficult to understand their calls（4） without without learning.It is a skill that very（5） few few animals have，only including humans，elephants and bats. ● Dolphins often（6） touch touch each other to express friendship.
	Elephants	● （7） Like Like dolphins，elephants also communicate with sound and movements of their body. ● Elephants can know each other（8） soon soon by their great sense of smell.
Further study	● Scientists are not（9） sure sure why dolphins and elephants share the gift of communication. ● Scientists（10） wonder wonder if they have nicknames.