Tooth Morphology in Fossil and Extant Lagomorpha (Mammalia) Reflects Different Mastication Patterns
Tooth Morphology in Fossil and Extant Lagomorpha (Mammalia) Reflects Different Mastication Patterns
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化石和现存兔形目（哺乳动物）的牙齿形态反映了不同的咀嚼模式
DOI：
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发表时间：
2010
影响因子：
1.9
通讯作者：
I. Ruf
中科院分区：
文献类型：
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作者：
W. Koenigswald;Ulrike Anders;S. Engels;J. Schultz;I. Ruf
从化石和现存物种牙齿形态的不同方面，对兔形目颊齿的功能和咀嚼周期进行了解释。咀嚼是由一个几乎垂直的剪切和横向研磨在舌方向。剪刃不仅表现为切面，而且表现为釉质增厚。一个主要的剪切刀片（PSB）继承干兔形目发生在所有检查的物种。它可以与第1和第5方面相关联（Crompton 1971），并且在极少数哺乳动物中出现;在姊妹分类单元啮齿目中明显缺失。次级剪刃（SSB）发生在衍生的鼠兔科和两个基础的兔科（Romerolagus和Pronolagus）作为一个收敛的模式。在来自欧洲的鼠兔化石中，“Lagicone结构”逐渐减少，有利于SSB。因此，鼠兔加强了剪切能力，而大多数兔喜欢通过凹褶的釉质带的部分细锯齿实现研磨功能。对于咀嚼周期，不同的阶段被确认，与tribosphenic模型的第一阶段有关。第一个运动（阶段Ia）几乎是直接的，第二个（阶段Ib）舌。只有在欧洲兔是一个额外的阶段检测到，这可能对应于第二阶段。
The functional interpretation of the cheek teeth and the mastication cycle of Lagomorpha are deduced from various aspects of tooth morphology of fossil and extant species. Mastication is composed of an almost orthal shearing and transverse grinding in a lingual direction. Shearing blades are not only indicated by facets but as well by thickened enamel. A primary shearing blade (PSB) inherited from stem lagomorphs occurs in all examined species. It can be correlated with facets 1 and 5 (sensu Crompton 1971) and occurs in very few mammals; it is conspicuously absent in the sister-taxon Rodentia. A secondary shearing blade (SSB) occurs in derived Ochotonidae and two basal Leporidae (Romerolagus and Pronolagus) as a convergent pattern. In fossil ochotonids from Europe, the “lagicone structure” is gradually reduced in favor of the SSB. Thus, ochotonids strengthen the shearing ability, whereas most leporids favor the grinding function realized by the partial crenulation of the enamel band of the re-entrant folds. For the mastication cycle, the distinct phases were recognized, related to phase I of the tribosphenic model. The first movement (phase Ia) is directed almost orthally, the second (phase Ib) lingually. Only in Lepus europaeus was an additional phase detected, which might correspond to phase II.