Underpinning many aspects of kastom—particularly the grade systems of Ambae, Malakula, Ambrym, Pentecost and parts of Santo—is the desire for tusked pigs. Without prized pigs to ‘pay’ for entry into levels of the grade systems, the Kastom arts within this exhibition may well not have existed.
John Layard wrote about the grade-level system:
‘To achieve the results … one more thing is necessary; for every one of these acts depends for its efficacy on, and derives its sanction from, what is possibly the most important item in the whole ritual, namely the sacrifice of tusked boars’. 
The rearing and development of tusked pigs is no mean feat, and developing the aesthetic and valuable circular tusk is a long and painful journey for the pig. First, the upper canines are pulled out, as they naturally grind against the tusks, keeping them short and sharp. Without these upper teeth, the tusk can grow without limitation. A tusked pig is kept penned so it cannot damage its growing tusks and, while owned by men, it is their wives who care for and feed the pigs. As its tusk grows, following its curved trajectory, it slowly pierces the pig’s cheek, then curves back into the jawbone. Pigs at this stage of tusk curvature are known as Bumto in northern Ambrym. Sometimes the tusk can continue to circle a second and a third time, and the life of a pig kept for its tusks is one of constant pain. During this process the wife may even chew the food for the pig, as it is unable to do so itself.
The tusk is the only part of the pig that matters, and is measured during stages of its growth by its amount of circling or, more correctly, spiralling, with set levels of value. To own one or more prized pigs with impressive spiral tusks is the measure of the owner’s wealth and status—as ethnologist Speiser observed, in the early twentieth century, ‘a valuable boar would be as famous as a race horse and its name known widely’.
Pigs would be sacrificed at each level of a grade system. A tusked pig is an important public sacrifice of an individual’s wealth, and tusked pigs can often be lent to other men for grade-taking sacrifices. Tusked pigs are an integral part of the grade-system economy, and when lent to others for grade-taking events it is with the expectancy of repayment (with interest) in the form of another pig with greater tusks or that the same pig will be returned in health, if not sacrificed, showing continued tusk growth.
It takes about six or seven years for a tusk to complete a circle, during which a penned or tied pig that cannot feed itself in the later stages of tusk growth can get fatally sick—it is a considerable effort to keep a tusked pig alive until it can be used as ‘payment’ in the grade system. The owner would sacrifice his tusked pig (or pigs, depending on the rank he is attaining—the number of pigs can be in the hundreds) by beating its head with a specially carved hammer at the public grade-taking ritual. Afterward, he would keep the jaw with the spiral tusks, or wear single spiral tusks (Leo in northern Ambrym) as a sign of the prized pigs he sacrificed and as insignia of his high standing.
 JW Layard, Stone Men of Malekula: Vao, Chatto & Windus, London, 1942. p 14.
 Speiser, Felix. & Stephenson, D. Q. Ethnology of Vanuatu: an early twentieth century study / Felix Speiser; translated by D.Q. Stephenson Crawford House Press, Bathurst, N.S.W.: 1990 (1921). p 247.
Text © National Gallery of Australia, Canberra 2013
From: Crispin Howarth Kastom: Art of Vanuatu National Gallery of Australia, Canberra, 2013