Raw data for: Over-eruption in marsupial carnivore teeth: compensation for a constraint

Pronounced over-eruption of the canine teeth, much greater than in
eco-morphologically equivalent placental carnivores, occurs with age and
growth in Australian marsupial carnivores. Suppression of functional tooth
replacement is a characteristic of marsupials and is frequent among
diverse placentals, where the primitive therian pattern is two generations
of incisor, canine and premolar teeth. Rapid determinate growth is one
among multiple hypotheses proposed to explain the loss of tooth
replacement in mammals. In this line of reasoning, the animal reaches a
sufficient body or jaw size to accommodate adult-sized teeth by the time
it requires functional dentition. Marsupial carnivores have a full set of
adult anterior teeth at weaning, which erupt into a juvenile jaw that is
25 to 30 % adult size, compared with well grown in placental carnivores.
Indeterminate over-eruption of the canine teeth in marsupial carnivores
results in increasing canine height and diameter with increasing body size
with age, suggesting this is a compensatory mechanism for the constraint
of a single generation of anterior teeth. Patterns of over-eruption in
different tooth types of marsupial carnivores are consistent with two
non-exclusive mechanisms that operate in other mammals, a response to
tooth wear and lack of an occlusal partner.