LifeSwimming in a school may help fish hear dolphins’ ultrasound clicks Models suggest the arrangement of American shad in a shoal amplifies the ultrasonic clicks that dolphins use to hunt, helping the fish detect and evade these predators 51¶¯Âþ
PhysicsWhy is there a cosmic speed limit? It could even be why we're here Nothing in the cosmos can travel faster than light speed. By distinguishing cause and effect and stopping everything happening in a jumbled mess, our existence depends on it Features