Doctoral Dissertation Improvement: Dental Microstructure and Growth in the Cebidae

博士论文改进：齿科动物的牙齿微观结构和生长

• 批准号: 0622479
• 负责人: Alfred Rosenberger
• 金额: --
• 依托单位: CUNY Brooklyn College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2007-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0622479&HistoricalAwards=false
• 关键词: Doctoral; Dissertation; Improvement; Dental; Microstructure

Teeth are obviously important in feeding and vital to discovering crucial ecological information about extinct species, including our own prehistoric ancestors. They also embed environmentally related forensic information. Teeth grow in a periodic, incremental manner similar to the way tree rings grow, and thus preserve a permanent record of their own formation. They develop along a time schedule that is coordinated adaptatively with events like weaning, with the nature of non-maternal food resources, and even the maturation of an individual as he/she develops their own species-specific social roles. Ongoing research aims to delineate this type of information from teeth among several primate groups, but major gaps remain. This project is the first to focus on dental microanatomy and growth in New World primates, specifically the capuchins, squirrel monkeys, tamarins, and marmosets. As an example where this work addresses new issues of wide significance, it is not known if seasonal dietary fluctuations impact overall bodily growth rates of a given species. Such information is hard to come by, even when monitoring animals in the wild. However, the approach of this study can reveal if incidental lean periods, as occurs during the dry season for many rain forest species, influences growth rates of teeth, which mirrors overall body growth. As another instance, although it is common for male primates to have larger canine teeth than females when living under certain social and mating systems, we understand little about how canine tooth size differences develop, meaning our understanding of the pervasive phenomenon of sexual dimorphism is rather incomplete. In a more general vein, most research in this field has concentrated on broadly surveying differences among families of primates, or higher taxonomic levels. Thus we know little about dental growth and its patterns at the species and genus level, or within an adaptive radiation. By focusing on several species and genera of the platyrrhine primates this study promises to fill some of these gaps. Taxonomically, this group presents several advantages. They are arguably the largest and most diverse group of living primates but they have also been largely ignored in favor of their Old World cousins, such as macaques, baboons and apes. The animals chosen for this study (Family Cebidae) are a good place to start because they are dietetically diverse, with some species showing seasonal shifts in their diet. My pilot work has also revealed that some male cebids exhibit a pattern of canine growth that differs from Old World monkey models, suggesting that the platyrrhine monkeys may be more pertinent to reconstructing the early evolution of canines and social systems in higher primates. This project is to assist graduate student training. Some of the techniques that are being employed are new and, once proven, will enable researchers with various interests to take greater advantage of museum collections, including fossils, by allowing microanatomical information to be obtained without cutting teeth apart to expose their internal structure. The image databases that will be developed will be made publicly available on the web. All in all, the research will add a new aspect to our understanding of primate diversity and evolution.

牙齿显然在进食方面很重要，对于发现灭绝物种的关键生态信息至关重要，包括我们自己的史前祖先。 它们还嵌入了与环境有关的法医信息。 牙齿以周期性的方式生长，类似于树木年轮的生长方式，因此保留了其自身形成的永久记录。 它们沿着一个时间表发展，这个时间表与断奶等事件相协调，与非母体食物资源的性质相协调，甚至与个体的成熟相协调，因为他/她发展了自己的物种特异性社会角色。 正在进行的研究旨在从几个灵长类动物群体的牙齿中描绘出这种类型的信息，但主要的差距仍然存在。 这个项目是第一个专注于牙齿显微解剖和新世界灵长类动物的生长，特别是卷尾猴，松鼠猴，绢毛猴和绒猴。 作为一个例子，这项工作解决了具有广泛意义的新问题，目前还不知道季节性饮食波动是否会影响给定物种的整体身体生长率。 这些信息很难获得，即使在野外监测动物时也是如此。 然而，这项研究的方法可以揭示，在许多雨林物种的干旱季节发生的偶然的贫瘠时期，是否会影响牙齿的生长速度，这反映了整体的身体生长。 另一个例子是，尽管在某些社交和交配系统下，雄性灵长类动物的犬齿比雌性大是很常见的，但我们对犬齿大小差异如何发展知之甚少，这意味着我们对普遍存在的性二型现象的理解是相当不完整的。 在更一般的脉络中，这一领域的大多数研究都集中在广泛调查灵长类动物家族之间的差异，或更高的分类水平。 因此，我们对牙齿生长及其在种属水平上或适应性辐射内的模式知之甚少。 通过关注几个物种和属的阔鼻灵长类动物，这项研究有望填补这些空白。 从分类学上讲，这一组有几个优点。 它们可以说是现存灵长类动物中最大和最多样化的群体，但它们也在很大程度上被忽视，而被它们的旧世界表亲所青睐，如猕猴，狒狒和猿。 本研究选择的动物（Cebidae科）是一个很好的起点，因为它们的饮食多样，有些物种的饮食呈现季节性变化。 我的试点工作还显示，一些雄性cebids表现出与旧世界猴模型不同的犬科动物生长模式，这表明阔鼻猴可能更适合重建高等灵长类动物犬科动物和社会系统的早期进化。本项目旨在协助研究生的培养。 正在使用的一些技术是新的，一旦得到证实，将使具有各种兴趣的研究人员能够更好地利用博物馆收藏品，包括化石，从而无需将牙齿切开以暴露其内部结构即可获得显微解剖信息。 将开发的图像数据库将在网上公布。 总而言之，这项研究将为我们对灵长类动物多样性和进化的理解增加一个新的方面。