Ecological Significance of Individual Variation in Physiology

小行星9507488 哺乳动物牙齿中的釉质组织可以在 简单 平行 布置 的 微晶（非棱柱 搪瓷） 到 复杂 非平行排列（棱柱状釉质）。 棱柱状的牙釉质增加了牙齿的强度，但我们对非棱柱状牙釉质的功能知之甚少。 在人类中，非棱柱状釉质比下面的棱柱状釉质更能抵抗膳食酸和糖副产物的侵蚀性破坏。这项研究调查了一系列哺乳动物物种的牙齿结构，饮食多样性和唾液化学。 它将测试的假设，夸大的非棱柱形牙齿的表层是适应，允许饮食重点酸性或含糖的食物来源。 对于每一个物种，食物硬度，糖含量和酸度的天然饮食测量，在一起 唾液pH值和缓冲能力。 测量臼齿中非棱柱状釉质的比例 使用扫描电子显微镜。 具有高比例的非棱柱状釉质的哺乳动物被预测会消耗比那些表现出相对较少的非棱柱状釉质的物种所吃的食物更含糖、酸性和柔软的食物。 唾液pH值和缓冲能力预计相对 低 物种间 的 表现出 大比例的非棱柱状釉质。这项研究将提供证据 的 的 之间的相互作用 齿 牙釉质形态学、口腔生理学和摄食行为限制了哺乳动物选择食物的多样性。 它将导致更好地理解解剖学，生理学和行为之间的关系，影响动物分享食物植物资源的方式。 它将提供对灭绝或知之甚少的物种的饮食的深入了解。 这项研究的结果也可能产生洞察人类nonprismatic enamel在抵抗牙齿侵蚀和蛀牙的开始中的作用。

9507488 Dumont The organization of enamel in mammalian teeth can vary between simple parallel arrangement of crystallite (nonprismatic enamel) to complicated non-parallel arrangements (prismatic enamel). Prismatic enamel increases the strength of the tooth, but we know relatively little about the function of non-prismatic enamel. In humans, non- prismatic enamel is more resistant to erosive destruction by dietary acids and sugar by-products than is underlying prismatic enamel. This research examines tooth structure, diet diversity, and salivary chemistry in an array of mammal species. It will test the hypothesis that exaggerated superficial layers of nonprismatic tooth are adaptations that permit dietary emphases on acidic or sugary food sources. For each species, food hardness, sugar content and acidity of natural diets are measured, together with salivary pH and buffering capacity. The proportion of nonprismatic enamel in molar teeth is measured using scanning electron microscopy. Mammals with high proportions of nonprismatic enamel are predicted to consume foods that are more sugary, acidic, and softer than those eaten by species that exhibit relatively little nonprismatic enamel. Salivary pH and buffering capacity are predicted to be relatively lower among species that exhibit large proportions of nonprismatic enamel. This study will provide evidence of the interactions between tooth enamel morphology, oral physiology and feeding behavior that limit the diversity of foods that mammals select. It will lead to better understanding of the relationships between anatomy, physiology and behavior that influence the ways in which animals share food plant resources. It will provide insight into the diets of extinct or poorly known species. The results of this study may also yield insights into the role of human nonprismatic e namel in resisting dental erosion and the initiation of tooth decay.