Answer:
Elephant are large social animals which live in groups.They are very intelligent and uses different mode of communication for maintaining the social circle.
Generally Elephants produces a unique sound called infrasounds. This a a low frequency sounds(5hz) capable of traveling in kilometers(kilometres) with low pitch beyond human comprehension, of (20hz) This mode of private mode communication by the animals helps in the adaptation to survival of the animal in the social behaviour.Due to low pitch beyond human audibility,it is easier for elephants to communicate on sighting the common predator (Man) and therefore communicate the danger before the predator is aware.
These sounds were produced by focal folds and modified through the filtration of the sounds by the nasal passages and the nose.
At night time when sound travels faster,female elephants makes calls to males,(mostly in the sparse Savannah)which may attracts many males for mating over 300km2. Thus this low frequency sound of less than 100Hz is enough to ensure mating.
However, this would not be possible during the day where warmer air are closed to the ground and therefore reduce sound speed.Thus the low frequncy sound is well adapted for both reproduction and survival
