Have you ever watched that scene from [insert movie or discovery channel] where a bunch of elephants are standing together, going about their normal elephant activities, and then suddenly, they stop and run away together? When I first saw this scene, I was puzzled as to why this happened. It was quite strange to see these large but peaceful animals just instantaneously disperse for no good reason. In actuality, however, the elephants did have a reason for running off. They responded to a message sent to them by another elephant through infrasound.  Elephants are able to detect and send infrasound. Humans, on the other hand, cannot pick up or produce infrasound the same way elephants can. For any noise that is between the ranges of 20 to 20,000 Hz, we have no problem audibly hearing these sounds. Anything that is higher or lower than that range will not be heard by humans. Infrasound has a frequency that is below 20 Hz and usually, humans cannot detect audible infrasound.  However, although we cannot audibly hear infrasound, we are still able to feel the effects of this low frequency. What are the impacts of infrasound on humans? And how it is that if we are unable to hear it, it still has an impact on us?
Infrasound is found in two forms, it can be ‘man-made’ or created by ‘nature’. Extreme examples human productions of infrasound include aircraft and fireworks. The noise from factories and engines also attribute to making these low frequencies.  Natural productions of infrasound basically occur all the time. Weather disasters such as earthquakes, tsunamis, and volcanic eruptions emit infrasound. Phenomena like meteor impacts and aurora also create this low frequency. On a less extreme and more relatable scale, anyone who has ever been in a thunderstorm or very strong winds is likely to have experienced infrasound.  Instruments can also create these low frequencies. Organs pipes and bass instruments can produce infrasound as well.  As mentioned before, elephants are able to create and detect infrasound. They are the not the only species who have this trait. Pigeons, squid and rhinos are just a few among the many other animals who can participate in infrasonic communications.  And although many animals can use infrasound to speak, humans still cannot communicate through these low vibrations.