Dentition
Encyclopedia
Dentition pertains to the development of teeth
and their arrangement in the mouth
. In particular, the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiology of the teeth of an animal.
Animals whose teeth are all of the same type, such as most non-mammalian vertebrates, are said to have homodont dentition, whereas those whose teeth differ morphologically are said to have heterodont
dentition. The dentition of animals with two successions of teeth (deciduous
, permanent
) is referred to as diphyodont
, while the dentition of animals with only one set of teeth throughout life is monophyodont. The dentition of animals in which the teeth are continuously discarded and replaced throughout life is termed polyphyodont.
: a long row of pointed or sharp-sided, undifferentiated teeth (homodont) that are completely replaceable. The mammalian pattern is significantly different. The teeth in the upper and lower jaws in mammals have evolved a close-fitting relationship such that they operate together as a unit. "They occlude, that is, the chewing surfaces of the teeth are so constructed that the upper and lower teeth are able to fit precisely together, cutting, crushing, grinding or shearing the food caught between".
All mammal
s except the monotreme
s, the xenarthrans, the pangolin
s, and the cetacea
ns have up to four distinct types of teeth, with a maximum number for each. These are the incisor
(cutting), the canine
, the premolar
, and the molar
(grinding). The incisors occupy the front of the tooth row in both upper and lower jaws. They are normally flat, chisel-shaped teeth that meet in an edge-to-edge bite. Their function is cutting, slicing, or gnawing food into manageable pieces that fit into the mouth for further chewing. The canines are immediately behind the incisors. In many mammals, the canines are pointed, tusk-shaped teeth, projecting beyond the level of the other teeth. In carnivores, they are primarily offensive weapons for bringing down prey. In other mammals such as some primates, they are used to split open hard surfaced food. The premolars and molars are at the back of the mouth. Depending on the particular mammal and its diet, these two kinds of teeth prepare pieces of food to be swallowed by grinding, shearing, or crushing. The specialised teeth - incisors, canines, premolars, and molars - are found in the same order in every mammal.
In many mammals the infants have a set of teeth that fall out and are replaced by adult teeth. These are called deciduous teeth, primary teeth, baby teeth or milk teeth. Animals that have two sets of teeth, one followed by the other, are said to be diphyodont. Normally the dental formula for milk teeth is the same as for adult teeth except that the molars are missing.
The number of teeth of each type is written as a dental formula for one side of the mouth, or quadrant
, with the upper and lower teeth shown on separate rows. The number of teeth in a mouth is twice that listed as there are two sides. In each set, incisors (I) are indicated first, canines (C) second, premolars (P) third, and finally molars (M), giving I:C:P:M. So for example, the formula 2.1.2.3 for upper teeth indicates 2 incisors, 1 canine, 2 premolars, and 3 molars on one side of the upper mouth.
The deciduous dental formula is notated in lowercase lettering preceded by the letter d: e.g. di:dc:dm. An animal's dentition for either deciduous or permanent teeth can thus be expressed as a dental formula, written in the form of a fraction, which can be written as , or I.C.P.M / I.C.P.M. For example, the following formulae show the deciduous and permanent dentition of all catarrhine primate
s, including humans:
The greatest number of teeth in any known placental mammal was 48, with a formula of . However, no existing (or extant) placental mammal has this number. In extant placental mammals, the maximum dental formula is: Mammal teeth are usually symmetrical, but not always. For example, the aye-aye
has a formula of , demonstrating the need for both upper and lower quadrant counts.
teeth are I1, I2, C1, P3, P4, M1, M2, and M3. In humans, the third molar pertains to the wisdom tooth, whether or not it has erupted.
Regarding premolars, there is disagreement regarding whether the third type of deciduous tooth is a premolar (the general consensus among mammalogists) or a molar (commonly held among human anatomists). There is thus some discrepancy between nomenclature in zoology and in dentistry. This is because the terms of human dentistry, which have generally prevailed over time, have not included mammalian dental evolutionary theory. There were originally four premolars in each quadrant of early mammalian jaws. However, all living primates have lost at least the first premolar. "Hence most of the prosimian
s and platyrrhines have three premolars. Some genera have also lost more than one. A second premolar has been lost in all catarrhines. The remaining permanent premolars are then properly identified as P2, P3 and P4 or P3 and P4; however, traditional dentistry refers to them as P1 and P2".
s, chimpanzee
s, and australopithecine
s have an eruption sequence of M1 I1 I2 M2 P3 P4 C M3, whereas anatomically modern humans
have the sequence M1 I1 I2 C P3 P4 M2 M3. The later that tooth emergence begins, the earlier the anterior teeth (I1-P4) appear in the sequence.
). The structure and arrangement of teeth is constant and, although it is inherited, does not undergo extensive change during environmental change, dietary specializations, or alterations in use patterns. The rest of the skeleton is much more likely to exhibit change because of adaptation. Teeth also preserve better than bone, and so the sample of teeth available to archaeologists is much more extensive and therefore more representative.
Dentition is particularly useful in tracking ancient populations' movements, because, although all humans have the same basic 32 teeth, there are subtle differences in the shapes of incisors, the number of grooves on molars, and extra cusps on particular teeth. These differences can not only be associated with different populations across space, but also change over time so that the study of the characteristics of teeth could say which population one is dealing with, and at what point in that population's history they are.
(link provided to title page to give reader choice of scrolling straight to relevant chapter or perusing other material).
Tooth development
Tooth development or odontogenesis is the complex process by which teeth form from embryonic cells, grow, and erupt into the mouth. Although many diverse species have teeth, non-human tooth development is largely the same as in humans...
and their arrangement in the mouth
Mouth
The mouth is the first portion of the alimentary canal that receives food andsaliva. The oral mucosa is the mucous membrane epithelium lining the inside of the mouth....
. In particular, the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiology of the teeth of an animal.
Animals whose teeth are all of the same type, such as most non-mammalian vertebrates, are said to have homodont dentition, whereas those whose teeth differ morphologically are said to have heterodont
Heterodont
The anatomical term heterodont refers to animals which possess more than a single tooth morphology. For example, members of the Synapsida generally possess incisors, canines , premolars, and molars. The presence of heterodont dentition is evidence of some degree of feeding/hunting specialization...
dentition. The dentition of animals with two successions of teeth (deciduous
Deciduous teeth
Deciduous teeth, otherwise known as reborner teeth, baby teeth, temporary teeth and primary teeth, are the first set of teeth in the growth development of humans and many other mammals. In some Asian countries they are referred to as fall teeth as they will eventually fall out, while in almost all...
, permanent
Permanent teeth
Permanent teeth are the second set of teeth formed in humans. There are thirty-two permanent teeth, consisting of six maxillary and six mandibular molars, four maxillary and four mandibular premolars, two maxillary and two mandibular canines, four maxillary and four mandibular incisors.The first...
) is referred to as diphyodont
Diphyodont
A Diphyodont is an animal with two successive sets of teeth, first the "deciduous" set and later the "permanent" set. Most mammals are Diphyodonts. Diphyodonts contrast with Polyphyodonts, such as many fish, whose teeth are constantly replaced....
, while the dentition of animals with only one set of teeth throughout life is monophyodont. The dentition of animals in which the teeth are continuously discarded and replaced throughout life is termed polyphyodont.
Overview
Vertebrate dentition originated from a folding in of the placoderm's armour, evolving into the familiar condition of living reptiles, amphibians, and fishFish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
: a long row of pointed or sharp-sided, undifferentiated teeth (homodont) that are completely replaceable. The mammalian pattern is significantly different. The teeth in the upper and lower jaws in mammals have evolved a close-fitting relationship such that they operate together as a unit. "They occlude, that is, the chewing surfaces of the teeth are so constructed that the upper and lower teeth are able to fit precisely together, cutting, crushing, grinding or shearing the food caught between".
All mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s except the monotreme
Monotreme
Monotremes are mammals that lay eggs instead of giving birth to live young like marsupials and placental mammals...
s, the xenarthrans, the pangolin
Pangolin
A pangolin , also scaly anteater or Trenggiling, is a mammal of the order Pholidota. There is only one extant family and one genus of pangolins, comprising eight species. There are also a number of extinct taxa. Pangolins have large keratin scales covering their skin and are the only mammals with...
s, and the cetacea
Cetacea
The order Cetacea includes the marine mammals commonly known as whales, dolphins, and porpoises. Cetus is Latin and is used in biological names to mean "whale"; its original meaning, "large sea animal", was more general. It comes from Ancient Greek , meaning "whale" or "any huge fish or sea...
ns have up to four distinct types of teeth, with a maximum number for each. These are the incisor
Incisor
Incisors are the first kind of tooth in heterodont mammals. They are located in the premaxilla above and mandible below.-Function:...
(cutting), the canine
Canine tooth
In mammalian oral anatomy, the canine teeth, also called cuspids, dogteeth, fangs, or eye teeth, are relatively long, pointed teeth...
, the premolar
Premolar
The premolar teeth or bicuspids are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant, making eight premolars total in the mouth. They have at least two cusps. Premolars can be considered as a 'transitional tooth' during chewing, or...
, and the molar
Molar (tooth)
Molars are the rearmost and most complicated kind of tooth in most mammals. In many mammals they grind food; hence the Latin name mola, "millstone"....
(grinding). The incisors occupy the front of the tooth row in both upper and lower jaws. They are normally flat, chisel-shaped teeth that meet in an edge-to-edge bite. Their function is cutting, slicing, or gnawing food into manageable pieces that fit into the mouth for further chewing. The canines are immediately behind the incisors. In many mammals, the canines are pointed, tusk-shaped teeth, projecting beyond the level of the other teeth. In carnivores, they are primarily offensive weapons for bringing down prey. In other mammals such as some primates, they are used to split open hard surfaced food. The premolars and molars are at the back of the mouth. Depending on the particular mammal and its diet, these two kinds of teeth prepare pieces of food to be swallowed by grinding, shearing, or crushing. The specialised teeth - incisors, canines, premolars, and molars - are found in the same order in every mammal.
In many mammals the infants have a set of teeth that fall out and are replaced by adult teeth. These are called deciduous teeth, primary teeth, baby teeth or milk teeth. Animals that have two sets of teeth, one followed by the other, are said to be diphyodont. Normally the dental formula for milk teeth is the same as for adult teeth except that the molars are missing.
Dental formula
Because mammalian teeth are specialised for different functions, many mammal groups have lost teeth not needed in their adaptation. Tooth form has also undergone evolutionary modification as a result of natural selection for specialised feeding or other adaptations. Over time, different mammal groups have evolved distinct dental features, both in the number and type of teeth, and in the shape and size of the chewing surface.The number of teeth of each type is written as a dental formula for one side of the mouth, or quadrant
Circular sector
A circular sector or circle sector, is the portion of a disk enclosed by two radii and an arc, where the smaller area is known as the minor sector and the larger being the major sector. In the diagram, θ is the central angle in radians, r the radius of the circle, and L is the arc length of the...
, with the upper and lower teeth shown on separate rows. The number of teeth in a mouth is twice that listed as there are two sides. In each set, incisors (I) are indicated first, canines (C) second, premolars (P) third, and finally molars (M), giving I:C:P:M. So for example, the formula 2.1.2.3 for upper teeth indicates 2 incisors, 1 canine, 2 premolars, and 3 molars on one side of the upper mouth.
The deciduous dental formula is notated in lowercase lettering preceded by the letter d: e.g. di:dc:dm. An animal's dentition for either deciduous or permanent teeth can thus be expressed as a dental formula, written in the form of a fraction, which can be written as , or I.C.P.M / I.C.P.M. For example, the following formulae show the deciduous and permanent dentition of all catarrhine primate
Catarrhini
Catarrhini is one of the two subdivisions of the higher primates . It contains the Old World monkeys and the apes, which in turn are further divided into the lesser apes or gibbons and the great apes, consisting of the orangutans, gorillas, chimpanzees, bonobos, and humans...
s, including humans:
- Deciduous:
This can also be written as . (Superscript and subscript denote upper and lower jaw, i.e. do not indicate mathematical operations; the numbers are the count of the teeth of each type. The '-' in the formula are likewise not mathematical operators, but spacers. 'd' denotes deciduous, i.e. milk or baby teeth, and lower case also indicates temporary teeth. This is a redunancy.) Another anotation is , if the fact that it pertains to deciduous teeth is clearly stated, per examples found in some texts such as The Cambridge Dictionary of Human Biology and Evolution - Permanent:
This can also be written as . When the upper and lower dental formulae are the same, some texts write the formula without a fraction (in this case, 2.1.2.3), on the implicit assumption that the reader will realise it must apply to both upper and lower quadrants. This is seen for example throughout The Cambridge Dictionary of Human Biology and Evolution.
The greatest number of teeth in any known placental mammal was 48, with a formula of . However, no existing (or extant) placental mammal has this number. In extant placental mammals, the maximum dental formula is: Mammal teeth are usually symmetrical, but not always. For example, the aye-aye
Aye-aye
The aye-aye is a lemur, a strepsirrhine primate native to Madagascar that combines rodent-like teeth and a special thin middle finger to fill the same ecological niche as a woodpecker...
has a formula of , demonstrating the need for both upper and lower quadrant counts.
Tooth naming discrepancies
Teeth are numbered starting at 1 in each group, except the premolars which end at 4. Thus the humanHuman
Humans are the only living species in the Homo genus...
teeth are I1, I2, C1, P3, P4, M1, M2, and M3. In humans, the third molar pertains to the wisdom tooth, whether or not it has erupted.
Regarding premolars, there is disagreement regarding whether the third type of deciduous tooth is a premolar (the general consensus among mammalogists) or a molar (commonly held among human anatomists). There is thus some discrepancy between nomenclature in zoology and in dentistry. This is because the terms of human dentistry, which have generally prevailed over time, have not included mammalian dental evolutionary theory. There were originally four premolars in each quadrant of early mammalian jaws. However, all living primates have lost at least the first premolar. "Hence most of the prosimian
Prosimian
Prosimians are a grouping of mammals defined as being primates, but not monkeys or apes. They include, among others, lemurs, bushbabies, and tarsiers. They are considered to have characteristics that are more primitive than those of monkeys and apes. Prosimians are the only primates native to...
s and platyrrhines have three premolars. Some genera have also lost more than one. A second premolar has been lost in all catarrhines. The remaining permanent premolars are then properly identified as P2, P3 and P4 or P3 and P4; however, traditional dentistry refers to them as P1 and P2".
Dental eruption sequence
The order in which teeth emerge through the gums is known as the dental eruption sequence. Rapidly developing anthropoid primates such as macaqueMacaque
The macaques constitute a genus of Old World monkeys of the subfamily Cercopithecinae. - Description :Aside from humans , the macaques are the most widespread primate genus, ranging from Japan to Afghanistan and, in the case of the barbary macaque, to North Africa...
s, chimpanzee
Chimpanzee
Chimpanzee, sometimes colloquially chimp, is the common name for the two extant species of ape in the genus Pan. The Congo River forms the boundary between the native habitat of the two species:...
s, and australopithecine
Australopithecine
The term australopithecine refers generally to any species in the related genera Australopithecus or Paranthropus. These species occurred in the Plio-Pleistocene era, and were bipedal and dentally similar to humans, but with a brain size not much larger than modern apes, lacking the...
s have an eruption sequence of M1 I1 I2 M2 P3 P4 C M3, whereas anatomically modern humans
Anatomically modern humans
The term anatomically modern humans in paleoanthropology refers to early individuals of Homo sapiens with an appearance consistent with the range of phenotypes in modern humans....
have the sequence M1 I1 I2 C P3 P4 M2 M3. The later that tooth emergence begins, the earlier the anterior teeth (I1-P4) appear in the sequence.
Dental formulae examples
| MAMMAL | DENTAL FORMULA | COMMENT |
|---|---|---|
| Non placental | . | Non-placental mammals such as marsupial Marsupial Marsupials are an infraclass of mammals, characterized by giving birth to relatively undeveloped young. Close to 70% of the 334 extant species occur in Australia, New Guinea, and nearby islands, with the remaining 100 found in the Americas, primarily in South America, but with thirteen in Central... s can have more teeth than placentals. For example, the opossum (below) |
| Kangaroo Kangaroo A kangaroo is a marsupial from the family Macropodidae . In common use the term is used to describe the largest species from this family, especially those of the genus Macropus, Red Kangaroo, Antilopine Kangaroo, Eastern Grey Kangaroo and Western Grey Kangaroo. Kangaroos are endemic to the country... |
||
| Musky Rat kangaroo | ||
| All of Potoroidae Potoroidae The marsupial family Potoroidae includes the bettongs, potoroos, and two of the rat-kangaroos. All are rabbit-sized, brown, jumping marsupials and resemble a large rodent or a very small wallaby.- Characteristics :... except Musky Rat-kangaroo Musky Rat-kangaroo The Musky Rat-kangaroo is a marsupial species found in the rainforests of northeast Australia. Although some scientists place this species as a subfamily of the family Potoroidae, the most recent classification places it in the family Hypsiprymnodontidae with prehistoric rat-kangaroos.It is the... |
The marsupial family Potoroidae includes the bettongs, potoroos, and two of the rat-kangaroos. All are rabbit-sized, brown, jumping marsupials and resemble a large rodent or a very small wallaby. |
|
| Opossum | ||
| Placental | . | Some examples of dental formulae for placental mammals |
| Armadillo Armadillo Armadillos are New World placental mammals, known for having a leathery armor shell. Dasypodidae is the only surviving family in the order Cingulata, part of the superorder Xenarthra along with the anteaters and sloths. The word armadillo is Spanish for "little armored one"... |
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| Aye-aye Aye-aye The aye-aye is a lemur, a strepsirrhine primate native to Madagascar that combines rodent-like teeth and a special thin middle finger to fill the same ecological niche as a woodpecker... |
A Prosimian. The Aye-aye's deciduous dental formula (dI:dC:dM)is | |
| Badger Badger Badgers are short-legged omnivores in the weasel family, Mustelidae. There are nine species of badger, in three subfamilies : Melinae , Mellivorinae , and Taxideinae... |
||
| Big brown bat Big brown bat The Big Brown Bat is larger in size than comparative species of bats, from about 4 to 5 inches in body length, with a 11-13 inch wingspan and weighing 1/2 to 5/8 ounce. The fur is moderately long, and shiny brown... |
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| Red Bat Red bat Red bat may refer to:*Eastern Red Bat , a species of bat found in the Eastern United States*Western Red Bat , a species of bat found in Western United States, also called the "Desert red bat"... , Hoary Bat Hoary bat The hoary bat is a species of bat in the vesper bat family, Vespertilionidae. It occurs throughout most of North America and much of South America, with disjunct populations in the Galapagos and Hawaiian Islands... , Seminole Bat Seminole Bat The Seminole Bat is a species of vesper bat in the family Vespertilionidae. It is found in Mexico and the United States.... , Mexican Freetail Bat |
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| Cat Cat The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests... (deciduous) |
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| Cat Cat The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests... |
The last upper premolar and first lower molar of the cat, since it is a carnivore Carnivora The diverse order Carnivora |Latin]] carō "flesh", + vorāre "to devour") includes over 260 species of placental mammals. Its members are formally referred to as carnivorans, while the word "carnivore" can refer to any meat-eating animal... , are called carnassial Carnassial Carnassials are large teeth found in many carnivorous mammals, used for shearing flesh and bone in a scissor- or shear-like way. In the Carnivora, the carnassials are the modified last upper premolar and the first molar, but in the prehistoric creodonts, the carnassials were further back in the... s and are used to slice meat and skin. This means that the carnassials are always the fourth upper premolar and the first lower molar |
|
| Cow | ||
| Dog Dog The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in... (deciduous) |
||
| Dog Dog The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in... (permanent) |
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| Eulemur | Prosimian genus to which the large Malagasy or 'true' lemurs belong. Ruffed lemur Ruffed lemur The ruffed lemurs of the genus Varecia are strepsirrhine primates and the largest extant lemurs within the family Lemuridae. Like all living lemurs, they are found only on the island of Madagascar... s (genus Varecia), Dwarf lemur Dwarf lemur The dwarf lemurs are the lemurs of the genus Cheirogaleus. All of the species in this genus, like all other lemurs, are native to Madagascar.- Description :... s (genus Mirza), and Mouse lemur Mouse lemur The mouse lemurs are nocturnal lemurs of the genus Microcebus. Like all lemurs, mouse lemurs are native to Madagascar.Mouse lemurs have a combined head, body and tail length of less than , making them the smallest primates ; however, their weight fluctuates in response to daylight duration.Mouse... s (genus Microcebus) also have this dental formula, but the mouse lemurs have a dental comb Toothcomb A toothcomb is an anatomical structure found in strepsirrhine primates, which includes lemurs, lorises and galagos. A toothcomb consists of long, flat forward-angled teeth, and includes the lower incisors and the canine teeth... |
|
| Euoticus | Prosimian genus to which the needle-clawed bushbabies Needle-clawed bushbaby The needle-clawed bushbabies are the two species in the genus Euoticus, which is in the family Galagidae. Galagidae is sometimes included as a subfamily within the Lorisidae .* Genus Euoticus... (or galago Galago Galagos , also known as bushbabies, bush babies or nagapies , are small, nocturnal primates native to continental Africa, and make up the family Galagidae... s) belong. Specialised morphology for gummivory includes procumbent dental comb and caniniform upper anterior premolars. |
|
| Fox Fox Fox is a common name for many species of omnivorous mammals belonging to the Canidae family. Foxes are small to medium-sized canids , characterized by possessing a long narrow snout, and a bushy tail .Members of about 37 species are referred to as foxes, of which only 12 species actually belong to... (red) |
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| Guinea pig Guinea pig The guinea pig , also called the cavy, is a species of rodent belonging to the family Caviidae and the genus Cavia. Despite their common name, these animals are not in the pig family, nor are they from Guinea... |
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| Hedgehog Hedgehog A hedgehog is any of the spiny mammals of the subfamily Erinaceinae and the order Erinaceomorpha. There are 17 species of hedgehog in five genera, found through parts of Europe, Asia, Africa, and New Zealand . There are no hedgehogs native to Australia, and no living species native to the Americas... |
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| Horse Horse The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today... (deciduous) |
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| Horse (permanent) | Permanent dentition varies from 36-42, depending on the presence or absence of canines and the number of premolars. The first premolar (wolf tooth) may be absent or rudimentary, and is mostly present only in the upper (maxillary) jaw. The canines are small and spade-shaped, and usually present only in males. Canines appear in 20-25 % of females and are usually smaller than in males. | |
| Human (deciduous teeth Deciduous teeth Deciduous teeth, otherwise known as reborner teeth, baby teeth, temporary teeth and primary teeth, are the first set of teeth in the growth development of humans and many other mammals. In some Asian countries they are referred to as fall teeth as they will eventually fall out, while in almost all... ) |
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| Human (permanent teeth Permanent teeth Permanent teeth are the second set of teeth formed in humans. There are thirty-two permanent teeth, consisting of six maxillary and six mandibular molars, four maxillary and four mandibular premolars, two maxillary and two mandibular canines, four maxillary and four mandibular incisors.The first... ) |
This pattern is shared with Ape Ape Apes are Old World anthropoid mammals, more specifically a clade of tailless catarrhine primates, belonging to the biological superfamily Hominoidea. The apes are native to Africa and South-east Asia, although in relatively recent times humans have spread all over the world... s and Old World monkey Old World monkey The Old World monkeys or Cercopithecidae are a group of primates, falling in the superfamily Cercopithecoidea in the clade Catarrhini. The Old World monkeys are native to Africa and Asia today, inhabiting a range of environments from tropical rain forest to savanna, shrubland and mountainous... s (excluding Prosimii Prosimian Prosimians are a grouping of mammals defined as being primates, but not monkeys or apes. They include, among others, lemurs, bushbabies, and tarsiers. They are considered to have characteristics that are more primitive than those of monkeys and apes. Prosimians are the only primates native to... ), and is sometimes known as the cercopithecoid dental formula. |
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| Indri Indri The indri , also called the babakoto, is one of the largest living lemurs. It is a diurnal tree-dweller related to the sifakas and, like all lemuroids, it is native to Madagascar.- Etymology :... |
See comment | A prosimian. Dental formula disputed. Either or . Proponents of both formulae agree there are 30 teeth and that there are only four teeth in the dental comb. |
| Lepilemur Sportive lemur The sportive lemurs are the medium sized primates that make up the Lepilemuridae family. The family consists of only one extant genus, Lepilemur, as well as the extinct genus Megaladapis. They are closely related to the other lemurs and exclusively live on the island of Madagascar... |
A prosimian. The upper incisors are lost in the adult, but are present in the deciduous dentition. | |
| Lion Lion The lion is one of the four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg in weight, it is the second-largest living cat after the tiger... |
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| Mole Mole - Animals :* Mole or "true mole", many of the mammals in the family Talpidae, found in Eurasia and North America* Golden moles, southern African mammals, similar to but unrelated to Talpidae moles... |
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| Mouse Mouse A mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles... (House) |
Plains pocket mouse Plains Pocket Mouse The Plains Pocket Mouse They generally live directly underneath Spanish bayonet or prickly pear plants. They are accustomed to sandy soil and eat mostly seeds, large and small grasses and small leaves of plants... (Perognathus flavescens) have dental formula of |
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| New World anthropoids | See comment | All New World anthropoids have a dentition formula of or |
| Opossum | ||
| Pig Pig A pig is any of the animals in the genus Sus, within the Suidae family of even-toed ungulates. Pigs include the domestic pig, its ancestor the wild boar, and several other wild relatives... (deciduous) |
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| Pig Pig A pig is any of the animals in the genus Sus, within the Suidae family of even-toed ungulates. Pigs include the domestic pig, its ancestor the wild boar, and several other wild relatives... |
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| Rabbit Rabbit Rabbits are small mammals in the family Leporidae of the order Lagomorpha, found in several parts of the world... |
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| Raccoon Raccoon Procyon is a genus of nocturnal mammals, comprising three species commonly known as raccoons, in the family Procyonidae. The most familiar species, the common raccoon , is often known simply as "the" raccoon, as the two other raccoon species in the genus are native only to the tropics and are... |
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| Rat Rat Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus... |
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| Sheep (deciduous) | ||
| Sheep (permanent) | ||
| Shrew Shrew A shrew or shrew mouse is a small molelike mammal classified in the order Soricomorpha. True shrews are also not to be confused with West Indies shrews, treeshrews, otter shrews, or elephant shrews, which belong to different families or orders.Although its external appearance is generally that of... |
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| Sifaka Sifaka Sifakas are a genus of lemur from the family Indriidae within the order Primates. Their name of the family is an onomatopoeia of their characteristic "shi-fak" alarm call. Like all lemurs, they are found only on the island of Madagascar... s |
See comment | Prosimians. Dental formula disputed. Either or . Possess dental comb comprising fourt teeth. |
| Slender loris Slender loris The slender lorises are two species of loris native to India and Sri Lanka, the only members of the genus Loris:* the red slender loris, Loris tardigradus* the gray slender loris, Loris lydekkerianus... Slow loris Slow loris Slow lorises are a group of five species of strepsirrhine primates which make up the genus Nycticebus. Found in South and Southeast Asia, they range from Northeast India in the west to the Philippines in the east, and from the Yunnan province in China in the north to the island of Java in the south... |
Prosimians. Lower incisors and canines form a dental comb; upper anterior dentition is peg-like and short. | |
| Squirrel Squirrel Squirrels belong to a large family of small or medium-sized rodents called the Sciuridae. The family includes tree squirrels, ground squirrels, chipmunks, marmots , flying squirrels, and prairie dogs. Squirrels are indigenous to the Americas, Eurasia, and Africa and have been introduced to Australia... |
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| Tarsier Tarsier Tarsiers are haplorrhine primates of the genus Tarsius, a genus in the family Tarsiidae, which is itself the lone extant family within the infraorder Tarsiiformes... s |
Prosimians. | |
| Vole Vole A vole is a small rodent resembling a mouse but with a stouter body, a shorter hairy tail, a slightly rounder head, smaller ears and eyes, and differently formed molars . There are approximately 155 species of voles. They are sometimes known as meadow mice or field mice in North America... (field) |
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| Weasel Weasel Weasels are mammals forming the genus Mustela of the Mustelidae family. They are small, active predators, long and slender with short legs.... |
Dentition use in archaeology
Dentition, or the study of teeth, is an important area of study for archaeologists, especially those specializing in the study of older remains. Dentition affords many advantages over studying the rest of the skeleton itself (osteometryOsteometry
Osteometry is the study and measurement of human or animal skeleton, especially in an anthropological or archaeological context.In Archaeology it has been used to various ends in the subdisciplines of Zooarcaheology and Bioarchaeology....
). The structure and arrangement of teeth is constant and, although it is inherited, does not undergo extensive change during environmental change, dietary specializations, or alterations in use patterns. The rest of the skeleton is much more likely to exhibit change because of adaptation. Teeth also preserve better than bone, and so the sample of teeth available to archaeologists is much more extensive and therefore more representative.
Dentition is particularly useful in tracking ancient populations' movements, because, although all humans have the same basic 32 teeth, there are subtle differences in the shapes of incisors, the number of grooves on molars, and extra cusps on particular teeth. These differences can not only be associated with different populations across space, but also change over time so that the study of the characteristics of teeth could say which population one is dealing with, and at what point in that population's history they are.
Dentition discussions in other articles
Some articles have helpful discussions on dentition, which will be listed as identified.- Lemur
Further reading
See also preview pages in Google books(link provided to title page to give reader choice of scrolling straight to relevant chapter or perusing other material).