I have seen this on TV (Hogs Gone Wild), heard other hog hunters state it, and read it on various forums and it just struck me as a strange claim. Basically, when folks see a hog that is upset or angry, they will note that the hog is snapping its jaw and making a popping noise, teeth clacking. With an almost uncanny regularity, somebody will exclaim that the hog is "sharpening his teeth" or "sharpening his cutters." If given a chance to explain, the person will note that they pop their teeth together to sharpen their cutters on their whetters. This, of course, would seem to imply that the cutters have otherwise become dulled and that the boar, in his anger, is preparing for battle by resharpening his teeth. This then assumes that the abrasion between the cutters and whetters will produce a marked difference in the cutting edges in the short amount of time that the boar will be doing his jaw popping before possible battle, or in some cases, after already being in battle. I have done a lot of reading about wildlife and wildlife observation over the years and I can fnd no other examples of mammals that engage in this activity (or any reptiles that do as well) for which the claim is being made that the popping of the jaws is for the purpose of sharpening any teeth or other cutting edges (turtle beaks). So I had to wonder why it was that when scared or angered, that hogs (male and female) engage in the same jaw snapping/popping tooth clacking that many other animals engage in under the same very circumstances, and yet strangely the claim is only made that the boars are doing this to sharpen their teeth. So why are boars so unique in this behavior? They aren't. As near as I can tell from everything that Ican find so far, the notion that the boars are snapping their jaws for the purposes of sharpening their teeth is a myth perpetuatedover time, undoubtedly influence via the excitement of the moments that folks experience seeing and hearing it happen (especially if handling angered hogs), and based on a small amount of fact. It is a fact to say that the cutters and whetters grind against one another to produce sharper edges, primarily on the cutters (though some whetters can be sharp as well). However, the cutters and whetters are the canine teeth that in boars are ever-growing. The shape of the teeth is such that they are wider at the gumline that out from the mouth. The wider portion of the teeth grow out and basically forced against its opposing canine via the size, shape, and direction of growth of the tooth. As part of normal jaw movement and mastication (chewing), the cutters and whetters do wear or grind against one another. It happens continually, day in and day out. The process of wear (hence sharpening) isactually veryslow. Dentin and enamel are two of the hardest tissues produced by the animal's body. If they were softer tissue, the edges would dull very quickly and sharpening would produce considerable loss of tooth structure, the teeth being sharpened away to nothing faster than the teeth actually grow. In short, a boar's cutters are always being sharpened through normal activities. He can't just hone his teeth to a sharp edge whenever he needs to have sharp teeth. The dentin and enamal simply don't perform that way. The sharpening that occurs between the cutters and whetters is a very slow process that is continual. No doubt when you hear a big boar popping his jaw and gnashing his teeth, some sharpening is being done, but the few snaps and pops you hear are producing in inconsequential amount of wear and hence an inconsequential amount of sharpening compared to what goes on with the thousands and thousands of grinds that happen daily between the cutters and whetters. If the hog's teeth weren't sharp before you made him mad, his efforts aren't going to result in some instantly sharp teeth that will slide you open at a moment's notice. The danger to you from the sharpness of the teeth does not change because of a few jaw pops. The exclamation that "They're sharpening their teeth!!" is about as pointless as noting that the hog is at that very moment digesting food that is being converted to energy that he may use to fight you..."LOOK OUT! HE'S DIGESTING!!!!" Instead, the popping and snapping sound you hear is simply a display behavior, both visible and audible. When done by hogs (male and female) or by other animals, it is a sound that conveys messages as to the animal's state of mind, usually that the animal is fearful of a threat, angry, stressed due to threat,etc. This is something seen in many species of mammals from rodents to bears and even in some non-mammals. In summary, the concern over, "They're sharpening their teeth" when jaw popping is something of an oft-repeated myth, that like many myths is shrouded in both fact and fiction along with some misunderstanding of what is going on and some well intentioned warning.