Premium
The jaw lever system in ungulates: a new model
Author(s) -
Greaves W. S.
Publication year - 1978
Publication title -
journal of zoology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.915
H-Index - 96
eISSN - 1469-7998
pISSN - 0952-8369
DOI - 10.1111/j.1469-7998.1978.tb03282.x
Subject(s) - lever , ungulate , biology , anatomy , grinding , molar , posterior teeth , point (geometry) , orthodontics , geometry , mathematics , paleontology , ecology , physics , materials science , medicine , quantum mechanics , habitat , composite material
In ungulates the distance from the jaw joint to the last molar is approximately the same as that of the grinding tooth row length. An hypothesis is presented that attempts to explain why ungulate grinding teeth are positioned where they are along the jaw. If the jaw joint on the balancing side serves as the fulcrum in anisognathus animals, a region along the jaw is defined, corresponding to where teeth are actually found, where rather simple muscle action can apply equal forces at any point. The ability to produce the same force at any point in this region, as such, may not be the critical feature since anterior or posterior to this region, tooth placement produces either a relatively inefficient or an unstable condition.