Researchers found that dolphins known as spongers spend most of their time with other spongers. The study is in the journal Nature Communications.

 

Spongers are small substance* of dolphins at use marine basket*　sponger to hunt for prey. The dolphins weared the spongers over their beaks to protect themselves from rocks and broken corals when they are searching for nutrious food on the sea floor. 

 

Sponging is passed down from parents to their young. And because the practice is socially learned. Researchers agreed that spongers are culturally distinct from other dolphins.  These findings are consistant with the notion that dolphins form fision fusion societies, where all dolphins in a community belonged to the same larger group, but have specific friends who may spend most of their time with. Of course scientists have yet to find out which dolphin clique is the coolest.