12/5/2023 0 Comments Animal age excersize by teeth![]() ![]() As with humans, you can tell an ape’s age by looking at its teeth, says Erin Stromberg, primate keeper at the Smithsonian National Zoo. Peter Norris, Summer Hill, New South Wales, Australiaįor sure. The glow of a neon sign? That’s plasma at work, as is the image on your plasma TV screen.ĭo other animal species have baby teeth and adult teeth, like humans? That charge allows plasmas to behave in ways gases can’t. ![]() Like gases, plasmas have no fixed shape or volume but unlike gases, which are electrically neutral, plasmas are positively charged. Though the other three forms are more common on earth, plasma is the most common state of matter in the universe-it’s what stars are made of. The general consensus, says Katya Vines, senior science curriculum developer at the Smithsonian Science Education Center, is that there is a fourth fundamental state of matter that appears naturally: plasma. Yes, there are others-the universe has been found to be more complex since many of us were in high school. The whalebone whale and anteaters also have no teeth, but their diets do not require chewing.I was taught that there are three kinds of matter: solids, liquids and gases. The duck-billed platypus has its early-life teeth replaced by keratinous plates, which it uses to crush aquatic insects, crustaceans, and mollusks. Turtles have heavy jaw coverings, which are thin edged in the incisor region and wide posteriorly for crushing. Birds have beaks but depend on a gizzard to do the grinding that molars would usually perform. Some vertebrates do not have any teeth (complete anodontia) but have descended from ancestors that possessed teeth. The bat’s saliva contains an anticoagulant, and its tongue rolls up in a tube to suck or lap the exuding blood. The vampire bat has large canines, but its highly specialized upper incisors, which are V shaped and razor edged, are what remove a piece of the victim’s skin. Their diet consists of small invertebrates, woodlice, and fruit. Also, their small body can store only enough food for 1 to 2 h, so they must feed almost continually. Death occurs by starvation once the molars wear out. The shrew’s 1- to 1½-year life span is limited by the wear on their molars. The shrew has two hooked cusps on the upper first incisor. The flaps of skin relax for eating and drinking. There is a large diastema immediately posterior to the incisors, and flaps of skin fold inward and meet behind the incisors to seal off the back part of the mouth during gnawing. ![]() The posterior teeth have flat, rough edges on the occlusal surface, and they stop growing at 2 years of age. The incisors continue to grow throughout life. As the dentin wears off, this leaves very sharp cutting edges of enamel. They have very hard, bright orange enamel on the labial surface and much softer exposed dentin on the lingual surface. The beaver has four strong curved incisors. ‡Guinea pigs have the same formula, except that they have only one maxillary incisor. Tusks (the central incisors) can be as long as 1½ feet and weigh 440 pounds. Each molar weighs about 9 pounds and is nearly a foot long mesiodistally on the occlusal surface. The size is needed to provide mechanical support for the tusks (one third of their length is embedded in the skull) and the enormous molars. An elephant’s skull is not larger than necessary to house its brain. †Elephants have deciduous molars (Dm) but no premolars. *Pigs and hippopotami have the same formula, except that they have two or three upper and two or three lower incisors. Some Dental Formulae (Order of Teeth per Quadrant) and Interesting Facts about Teeth in Animals 2 – 4 Did you know that dogs have twice as many premolars as humans if you include uppers and lowers, as well as the right and left sides? Did you know that the tusks on an elephant are maxillary central incisors? Elephants have the largest diastema in the world, large enough for the massive trunk between their central incisors. They have three upper and three lower premolars on each side. Look at the formulas for animals in Table 1-6, and note that cows have no upper incisors or upper canines. It is interesting to note that the dentition of animals can be represented by the same type of formula as described above. The dental formula for the human permanent dentition, adding the new abbreviation for premolars (PM), is as follows: The formula used to represent teeth in the human primary dentition is as follows: ![]() INTERESTING VARIATIONS IN ANIMAL TEETH COMPARED TO HUMAN TEETH USING DENTAL FORMULAEĪ dental formula for the human primary dentition can be represented by placing the abbreviation for incisors (I) followed by an upper number representing the number of incisors in an upper quadrant over a bottom number representing the number of incisors in a lower quadrant (I 2/2), then the number of canines (C) in an upper and lower quadrant (C1/1), and then the number of molars (M) in an upper and lower quadrant (M2/2). ![]()
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