 Apart from the defense from predators, Jordania suggested that this system was the core strategy to obtain food via confrontational, or aggressive scavenging.Apart from loud rhythmic singing-stomping-dancing, Jordania also suggested that soft humming could have played an important role in the early human (hominid) evolution as contact calls.Many social animals produce seemingly haphazard and indistinctive sounds (like chicken cluck) when they are going about their everyday business (foraging, feeding).