Doctoral Dissertation Research: Fungiform Papillae and the Evolution of the Primate Gustatory System

任何灵长类物种的饮食是形成其解剖和行为的最重要的因素之一，而味觉在食物选择过程中起着关键作用。食物的营养成分差别很大。因此，为了满足他们的饮食要求，灵长类动物必须有选择性地摄入含有有益营养的食物，同时避免有毒或抑制消化的化合物。个人检测食物化学性质的一种方法是通过味觉。因此，一个物种的味觉系统的敏感性应该是饮食的一个重要决定因素。灵长类味觉解剖学的研究在这方面很重要，因为解剖学是敏感度的决定因素。尽管它对灵长类摄食生态学具有明显的意义，但对灵长类味觉解剖学的研究一直很少。该项目将对大量灵长类动物的舌头解剖进行详细研究，以便更好地确定影响灵长类味觉系统进化的选择压力。舌部解剖的变异将通过计算菌状乳头的密度来量化，菌状乳头是舌头前三分之二上唯一含有味蕾的结构。菌状乳头(DFP)的密度被认为是味觉敏感度的信息量，并与人类的食物选择直接相关。此外，众所周知，一些女性的DFPS明显高于男性。在人类女性中，较高的DFPS和较高的味觉敏感度可能会在怀孕和哺乳期间对食物进行更好的区分，以确保足够的营养和避免毒素。虽然食物对所有哺乳动物雌性动物都很重要，但这项研究将首次调查非人类灵长类动物味觉解剖的性别差异，并发现它们是否表现出与人类相同的模式。仔细研究影响灵长类味觉系统进化的选择性力量，对于全面了解灵长类的饮食适应和摄食生态至关重要。该项目将提供第一个广泛的，比较研究的舌头解剖和性别差异的味觉系统的非人类灵长类。通过辨别灵长类动物的舌头解剖是否与饮食有关，这项研究将有助于解释食物选择的感觉机制。它更广泛的意义在于，味觉敏感度在人类的饮食选择中发挥着重要作用，因此对人类健康至关重要。高敏感度品尝者的体重指数明显较低，这与许多健康益处有关。在这个项目中收集的数据对于理解味觉解剖变异、对特定食物的偏好和疾病预防之间的进化关系是不可或缺的。了解形成灵长类味觉系统的选择压力将为人类饮食选择的研究提供有价值的背景。

The diet of any primate species is one of the most important factors in shaping its anatomy and behavior, and the sense of taste (gustation) plays a key role in the food selection process. The nutritional content of food items varies considerably. Thus, to meet their dietary requirements primates must be selective, ingesting food items that contain beneficial nutrients while avoiding compounds that are toxic or inhibit digestion. One means by which individuals detect chemical properties of food items is through the sense of taste. Accordingly, the sensitivity of a species' gustatory system should be an important determinant of diet. Study of primate gustatory anatomy is important in this regard, because anatomy is a determinant of sensitivity. Despite its clear significance to primate feeding ecology, there has been a dearth of studies on primate gustatory anatomy. This project will provide a detailed study of lingual anatomy in a large sample of primates in order to better identify the selection pressures that have influenced the evolution of the primate gustatory system. Variation in lingual anatomy will be quantified by calculating the density of fungiform papillae, which are the only structures on the front two-thirds of the tongue that contain taste buds. The density of fungiform papillae (DFP) is known to be an informative measure of taste sensitivity, and has been directly associated with food choices in humans. Furthermore, some women are known to have significantly higher DFPs than men. It is possible that higher DFPs and greater taste sensitivities in human females permit better discrimination among food items during gestation and lactation in order to secure adequate nutrition and avoid toxins. Although food is important to all mammalian females, this study will be the first to investigate sex differences in the gustatory anatomy of non-human primates and discover whether they show the same patterns found in humans. Close examination of the selective forces that have influenced the evolution of the primate gustatory system is vital for a comprehensive understanding of primate dietary adaptations and feeding ecology. This project will provide the first broad, comparative study of lingual anatomy and sex differences in the gustatory system of non-human primates. By discerning whether lingual anatomy in primates is associated with diet, this study will help to explain the sensory mechanisms for food choice. Its broader significance lies in the fact that taste sensitivity plays a major role in dietary choices made by humans, and is thus important for human health. High-sensitivity tasters have significantly lower body mass indices, which are associated with numerous health benefits. The data collected in this project, will be integral to understanding the evolutionary relationship between variation in gustatory anatomy, preferences for particular food items, and prevention of illness. Knowledge of the selection pressures that shaped the primate gustatory system will provide a valuable context for research on human dietary choices.