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Since the origin of teeth some 450 mya, the vertebrate dentition has diversified within the reptiles, amphibians, and fish: however most of these groups continue to possess a long row of pointed or sharp-sided, undifferentiated teeth (homodont) that are completely replaceable. The mammalian pattern is significantly different.
In contrast, homodont or isodont dentition refers to a set of teeth that possess the same tooth morphology. In invertebrates, the term heterodont refers to a condition where teeth of differing sizes occur in the hinge plate, a part of the Bivalvia .
The dentition was typical for sloths, but in contrast to today's representatives it consisted of completely homodont teeth, which is a characteristic feature of megatherians. Each branch of the jaw had 5 teeth in the upper jaw and 4 in the lower jaw, so in total Eremotherium had 18 teeth.
Another similar feature was the composition of the teeth, which contained mostly calcium phosphate which is needed for eating and drinking by aquatic animals, though, unlike modern day toothed whales, they had a heterodont (more than one tooth morphology) dentition as opposed to a homodont (one tooth morphology present) dentition. [62]
The dentition of Cerrejonisuchus is generally homodont, although the third maxillary tooth is enlarged and the fourth is somewhat smaller than the rest. They are conical, labiolingually compressed, each having a relatively rounded apex.
Furthermore, they are believed to have had homodont dentition. [2] This, combined with its shovel like snout, indicate that Desmatosuchus fed by digging up soft vegetation. [7] This method of feeding is further evidenced by its toothless premaxilla and dentary tip, which were covered in horny sheaths.
The dentition is morphologically homodont (teeth do not vary in shape), although the rows of teeth do decrease in size further into the mouth. The teeth on the frontmost row are over twice the crown height of those of the backmost row.
The dentition is another featured trait in therizinosaurids which differs from all theropod groups. At least two different tooth morphologies are observed among therizinosaurids; the first is represented by relatively homodont, oval to lanceolate-shaped teeth with moderate coarse denticles (serrations) on the crowns (upper exposed