The clicks are made by the eland's tendon. As it slips over a bone in the knee, it vibrates like a string, and like any string, the frequency of the sound wave it produces falls as its diameter and length increase. So as an eland grows and its tendon gets longer and wider, its knee-clicks deepen.

Are Elands aggressive?

In males they form a wide "V" and can grow to 120 cm / 4 feet in length. ... There is no evidence of territoriality, and males rarely display aggressive tendencies, even during the breeding season. Giant eland are alert and wary, making them difficult to approach and observe.

Is an eland a deer?

What is an Eland? An Eland is a type of antelope. It is a member of the Bovidae family and there are two different types of Eland in the world.