What anatomical features have elephants developed that enable them to make such low frequency and powerful vocalizations?
First and foremost elephants are large and thus all of the organs involved in sound production are large and therefore able to produce relatively low frequency sounds. An elephant’s vocal chords are very long and rather loosely attached and so just like a musical instrument with long and loose strings the elephant’s larynx can produce very low sounds. In addition, elephants have an especially large resonating chamber that includes the mouth, trunk, some 3 meters in length and the pharyngeal pouch, a structure unique to elephants.