Tuesday, September 12, 2017

Elephant communication 🐘

Elephants have complex ways of communicating with each other that involve olfactory, visual, tactile and auditory signals.

They are highly social mammals that live in very complex societies. In this sense, the acoustic communication plays an essential role in locating individuals and maintaining intra- and inter-group cohesion.

The elephant society is a fission-fusion model where individuals aggregate and dissociate based on ecological stressors and other factors such as predator pressures, calf care, and mate selection. As explained in “#ElephantTuesdays: oh mama! a female´s role, the core unit of the elephant social structure is the family unit which consists of an adult female and her offspring. Family units that are found to be highly associated are bond groups. To maintain cohesion and coordination of the family group and association with bond groups, numerous tactile and visual communication cues are used along with a complex system of auditory signals.

Elephants produce a broad range of higher frequency sounds like barks, roars, cries and snorts. But
the most frequently used sounds they produce are the “rumbles”. Rumbles are very low frequency sounds that were originally thought to be originated in the elephant´s stomach (stomach rumbles). These low frequency sounds can reach up to 2 kilometers (Langbauer et al. 1991, McComb et al. 2003) and are used for communication between and within family herds over large distances.

If we compare the range of frequencies used by elephants with those used by humans, we can get an idea of how amazingly low these rumble frequencies can be: a typical human´s voice in speech is about 110 Hz for men, 220 Hz for women and 300 Hz for children, while a typical male rumble is about 12, a female´s rumble is about 13Hz and a calf´s 22Hz.

Original video: ACP000dlbi

It is known that the frequency of the sound is correlated to the level of excitement of the elephant; they produce low frequency sounds when they are in a low level of excitement. These sounds are used to promote group cohesion. In contrast, high frequency sounds are present when the elephants are highly excited.

They are not only great at producing sounds, but also at localizing them: it has been suggested that the larger the space between an elephant´s ears (inter-aural space), the better the ability at localizing sounds, so they extend their ears perpendicularly to their heads in order to localize sounds.

When an elephant rumbles, a replica of the airborne sound is also transmitted through the ground. Seismic communication could supplement airborne communication or be especially beneficial when airborne conditions are not ideal for transmission. (O'Connell-Rodwell, C.E. 2007. Keeping an "ear" to the ground: Seismic communication in elephants. Physiology 22:287-294.).

Elephants also use other senses to communicate, like their vision. Here we talk about visual communication: if you watch an elephant for a long while, you will see a large repertoire of visual signals that they perform to communicate with one another (or with other species) by using their heads, eyes, mouth, ears, trunk, tail, feet and their whole body. So, if you happen to be in front of an elephant and s/he starts run to you, head up high above his/her shoulders, spread ears, you´d better run fast if you have the chance, or start your car and speed up! S/he is telling you that you are not welcomed; it´s a threatening or dominant signal. A subordinate elephant carries his/her head low and his/her ears back. A socially excited elephant rapidly flaps his/her ears, eyes open. A frightened or excited one raises his/her tail and chin, remember?

Original video: ACP0000b7b

You all might remember the blog post about the “elephant trunk”, talking about the elephant´s trunk abilities. They are very tactile animals that touch each other with their entire body to communicate in several contexts like defensive, sexual, playful behaviors etc.

But the trunk is the part of their body with which they more often touch each other to communicate. Remember this video? a beautiful example of tactile communication:

Original videos: ACP000cb8k ACP000cb8l ACP000cb8n

They also use chemical signals to communicate. Trunks up to sniff the air, exploring the ground for urine trails etc., sniffing genitals, mouths, glands or ears of partners…chemical communication gives an efficient long-lasting signal.

Original video: ACP0002p30

Anyone interested in learning more about elephant communication, this is a very interesting visual guide: "What Elephant Calls Mean: A User's Guide" published by National Geographic in 2014

Thanks for reading :-)


Langbauer Jr., W.R. 2000. Elephant Communication
Berg, J.K. 1983. Vocalizations and associated behaviours of the African elephant Loxodonta africana in captivity.
Elephant Voices: https://www.elephantvoices.org/

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