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Title: Teeth that never stop growing Written by: bio_man on Jan 22, 2022 (https://biology-forums.com/gallery/44/6_22_01_22_1_48_59.jpeg) (https://biology-forums.com/index.php?action=gallery;sa=view;id=44062) Rodents are mammals characterized by a pair of broad, sharp-edged, chisel-like incisor teeth that are firmly inserted in both jaws and are used in gnawing vegetation. The front surface of each incisor tooth is composed of enamel, and the hind surface is of soft dentine wears away during the process of gnawing so that the teeth are constantly kept sharp. Shown above is a beaver sporting bright orange teeth; the reason they are orange is because of an unusually high concentration of iron in the enamel. Unlike human teeth, the incisors of rodents don't have roots, and they never stop growing! To keep these teeth from growing into their brains, rodents grind their teeth against each other. This friction is similar to using a grindstone to sharpen a knife. "Self-sharpening" not only keeps the teeth short, but it also keeps the edges very sharp and chisel-like. Interestingly, rodents have no canine teeth; a gap is present between the incisors and the grinding teeth, or molars. Scientific classification: Rodents make up the order Rodentia. Comments: thanks it was very informative Written by: suekohn22 on Feb 8, 2022 |