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WonderAnimal communication fact

Elephants generate and detect low-frequency ground vibrations, using sensitive feet and trunks to receive seismic information carried through soil.

Seismic communication

NatureBiologyScience

The story behind the card

The biologist Caitlin O'Connell-Rodwell began studying this in African elephants in Namibia in the 1990s. Her team found that an elephant's low rumbles and stamps also send vibrations through the ground, and that other elephants react when such signals are played back through the soil. Researchers estimate that these ground waves may carry for several kilometres, in some conditions further than the same call through the air. Elephants seem to pick them up in two ways: through pressure-sensitive nerve endings called Pacinian corpuscles in the feet and trunk, and through vibration travelling up the leg bones to the inner ear. Elephants have been seen leaning forward or lifting a foot as if listening. How much the ground channel can carry is still being studied.

Türkçe oku
Filler yere düşük frekanslı titreşimler gönderir ve başka fillerin gönderdiği titreşimleri algılar. Topraktan gelen bu sinyalleri son derece hassas ayakları ve hortumlarıyla alırlar.

Biyolog Caitlin O'Connell-Rodwell, Afrika fillerindeki bu iletişimi 1990'larda Namibya'da incelemeye başladı. Ekibi, fillerin derinden gelen homurtularının ve yere vuruşlarının toprakta da titreşim yarattığını, bu titreşimler topraktan dinletildiğinde başka fillerin tepki verdiğini gösterdi. Araştırmacıların tahminine göre bu yer dalgaları birkaç kilometre uzağa ulaşabilir; bazı koşullarda aynı çağrının havada gidebildiğinden de uzağa. Filler bu sinyalleri iki yoldan alıyor gibi görünüyor: ayaklarındaki ve hortumlarındaki, Pacini cisimcikleri denen basınca duyarlı sinir uçlarıyla ve bacak kemiklerinden iç kulağa ulaşan titreşimle. Fillerin dinler gibi öne eğildiği ya da bir ayağını kaldırdığı görülmüştür. Toprak yoluyla ne kadar bilgi taşınabildiği hâlâ araştırılıyor.

Sources and further reading

Background reading: Seismic communication
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