Vestigial Tooth Anatomy and Tusk Nomenclature for Monodon Monoceros

  title={Vestigial Tooth Anatomy and Tusk Nomenclature for Monodon Monoceros},
  author={Martin T. Nweeia and Frederick C. Eichmiller and Peter V. Hauschka and Ethan M. Tyler and James G. Mead and Charles Potter and David P. Angnatsiak and Pierre Richard and Jack R. Orr and Sandie R. Black},
  journal={The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology},
Narwhal tusks, although well described and characterized within publications, are clouded by contradictory references, which refer to them as both incisors and canines. [] Key Result Examination of 131 skull samples, including 110 museum skull specimens and 21 harvested skulls, revealed the erupted tusks surrounded by maxillary bone over the entire length of their bone socket insertion, and are thus more accurately termed caniniform or canine teeth.
Shrew dentition (Lipotyphla: Soricidae)—endodontic morphology and its phylogenetic resolving power
It is suggested that pulp endocast analysis be added to the analysis of the tooth surface to achieve the broadest and most productive use of tooth morphology.
Tooth replacement patterns in the Early Triassic epicynodont Galesaurus planiceps (Therapsida, Cynodontia).
The growth series shows that the incisors and postcanines continue to develop and replace, even in the largest (presumably oldest) specimen of the Early Triassic cynodont Galesaurus planiceps, which had a finite number of canine replacement cycles.
Maxillary canine tooth growth in babirusa (genus Babyrousa)
It is hypothesised that some form of connective tissue, stretching from the flange to the subcutaneous tissues of the forehead, exerts a caudally orientated pulling force that results in the gradual rotation of the alveolar process.
Vestigial teeth of the Pacific walrus Odobenus rosmarus divergens Illiger, 1815 (Carnivora: Odobenidae)
Vestigial teeth of the Pacific walrus from the Chukotka Peninsula (Russia) were examined and the weight and width of the upper second incisor and the upper fourth premolar will increase relative to the number of annual cement layers added.
Sensory ability in the narwhal tooth organ system
The combined evidence suggests multiple tusk functions may have driven the tooth organ system's evolutionary development and persistence and new findings of sexual foraging divergence documented by stable isotope and fatty acid results add to the discussion of the functional significance of the narwhal tusk.
Formation, structure, and function of extra‐skeletal bones in mammals
  • A. Nasoori
  • Biology
    Biological reviews of the Cambridge Philosophical Society
  • 2020
This review provides the first extensive comparative description of the skeletal and integumentary systems of AHOOOs in a variety of mammals.
First monodontid cetacean (Odontoceti, Delphinoidea) from the early Pliocene of the north‐western Pacific Ocean
Monodontids are among the most enigmatic cetaceans due to their scarcity in the fossil record. Previously, except for fragmentary materials, only three skulls were known from the pre‐Pleistocene;
Biocomposites and Mineralized Tissues
Bone originated as mineralization around the basal membrane of the throat or skin, giving rise to tooth-like structures and protective shields in animals with a soft cartilage-like endoskeleton, and shows a broad variety of mechanical adaptations at nano- and microscales.
Molecular decay of enamel matrix protein genes in turtles and other edentulous amniotes
The fossil record and phylogenetics combine to predict the occurrence of molecular fossils of tooth-specific genes in the genomes of edentulous amniotes, and in every case these molecular fossils have been discovered.
Functional or Vestigial? The Genomics of the Pineal Gland in Xenarthra.
It is suggested that the recurrent inactivation of melatonin genes correlates with pineal atrophy and endorses the use of genomic analyses to ascertain the physiological status of suspected vestigial structures.


Comparisons with newly recovered and as yet undescribed cranial material of Titanohyrax reveal more characters shared by these genera, strengthening the case for their inclusion as sister taxa within the Titanohyracinae.
Cranial structure and relationships of the Liassic mammal Sinoconodon
The structure of recently discovered ‘Rhaeto-Liassic’ mammals and that of Sinoconodon indicates that there was greater diversity among the earliest known mammals than was previously thought.
The anatomy of Odobenocetops (Delphinoidea, Mammalia), the walrus‐like dolphin from the Pliocene of Peru and its palaeobiological implications
The Pliocene Beds of the Pisco Formation on the southern coast of Peru have yielded three new skulls of the walrus-like odontocete, Odobenocetops, which confirm referral to the Order Cetacea and the morphology of the humerus reinforces affinities of odobenOCetopsids to monodontids.
Histogenesis of the chequered pattern of ivory of the African elephant (Loxodonta africana).
Odobenocetops peruvianus, theWalrus-Convergent Delphinoid, Mammalia: Cetacea, from the Early Pliocene of Peru
The highly modified morphology of the rostrum indicates that there was no melon as in all other odontocetes, and therefore that Odobenocetops was probably unable to echolocate; binocular vision could have compensated for this inability.
The skull of the foetal narwhal, Monodon monoceros L
  • N. B. Eales
  • Biology
    Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
  • 1950
The study leads to the conclusion that the narwhal is more closely related to the Delphinidae than to the Phocaenidae, and that it approaches the DelPHinidae through Globiocephala.
Tooth eruption in Reeves' muntjac (Muntiacus reevesi) and its use as a method of age estimation (Mammalia: Cervidae)
The sequence of tooth eruption and replacement in Reeves' muntjac was determined from captive animals of known age. Pronounced sexual dimorphism is shown by the permanent upper canine which in the
Colyer's Variations and diseases of the teeth of animals
This chapter discusses variations in Number, Sixe and Shape, as well as other Disorders of Teeth and Jaws, and some of the causes of tooth destruction from causes other than caries.
Discriminating Proboscidean Taxa Using Features of the Schreger Pattern in Tusk Dentin
The ability of the Schreger pattern to distinguish tusk dentin of proboscidean taxa should prove useful to archaeologists in a variety of contexts.
Morphological aspects and composition of African elephant ( Loxodonta africana ) ivory
Fragments of ivory and tusks obtained through the National Parks Board from the Kruger Park, Addo Elephant Park, Kaokoveld, Caprivi, Etosha, Kavango and Tembe Elephant Park showed distinctive diamond shaped pattern caused by the sinusoidal surface to pulpal course followed by odontoblastic tubules.