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||Published: 14 November, 2007
Chinese water deer's canine teeth used to scare away others
Why do chinese water deer have canine teeth?
Let's start by asking, " what is a deer?" Deer are in the mammalian family Cervidae, a group that generally is characterized by the presence of antlers. Antlers are bony outgrowths that are generally shed and re-grown on an annual cycle. There are many ideas about why deer have antlers, and we'll get back to that below. But, in terms of the Chinese water deer, these are one of two groups of cervids (deer) that have enlarged canine teeth and that lack antlers. Canine teeth, the larger teeth near the front of the mouth, are something we associate with dogs and are found in many kinds of mammals. In those deer that lack antlers, the upper canine teeth are enlarged and sharp, and are clearly used as display mechanisms to scare away less dominant animals. In more drastic use, these canine teeth are used to fight fairly wicked battles. The deer of North America, in contrast, lack upper canine teeth. In white tailed deer, only the male deer (the buck) bears antlers, which grow ever-larger as the animal matures. These bucks use the antlers to intimidate smaller bucks, or during the rutting season will use the antlers to fight with other bucks. Thus, the antlers of our deer and the canine teeth of the Chinese water deer have relatively similar functions in male against male competition during the breeding season. Some biologists question the inclusion of the water deer (and the other genus and species of "deer" that lack upper canine teeth) in the deer family. But, other features of the animal including anatomy and genetics have argued for the retention of these animals within the Cervidae. That could be the topic of another commentary. Our antlered "deer" include white-tailed deer in the eastern United States, and mule deer which are primarily western. Additionally, the deer include elk, caribou and moose. Some of these are found throughout the world in the northern hemisphere. The Chinese water deer is found in the Yangtze River region of China. These deer are rather small, weighing only about 20-25 pounds. But, given the tusk-like nature of their canines, let's be glad for their small size. Males square off against rival males and attack by swinging their heads and teeth against their opponents neck and chest. The battles can and often do result in injuries.