Tusks

An elephant's tusks cannot be retracted.

Elephant tusks are made out of ivory.

Elephant tusks consist of ivory.

Tens of thousands of elephants are killed every year for their ivory tusks.

Narwhals have long tusks.

A hippopotamus has huge tusks.

Hippos have huge tusks.

A very different and fairly common quasi-human kind was sometimes produced by planets rather larger than the Earth. Owing to the greater strength of gravitation, there would first appear, in place of the familiar quadruped, a six-legged type. This would proliferate into little sextuped burrowers, swift and elegant sextuped grazers, a sextuped mammoth, complete with tusks, and many kinds of sextuped carnivora. Man in these worlds sprang usually from some small opossum-like creature which had come to use the first of its three pairs of limbs for nest-building or for climbing. In time, the forepart of its body thus became erect, and it gradually assumed a form not unlike that of a quadruped with a human torso in place of a neck. In fact it became a centaur, with four legs and two capable arms. It was very strange to find oneself in a world in which all the amenities and conveniences of civilization were fashioned to suit men of this form.

Elephants are illegally hunted for their ivory tusks.

The tusks of this elephant are impressive.