Doctoral Dissertation Improvement: A Behavioral and Genetic Study of Color Vision Polymorphism in Squirrel Monkeys

本项目的目的是研究南美松鼠猴的种内颜色视觉系统的变异。南美松鼠猴是新大陆灵长类的模式分类群。与非洲和亚洲灵长类不同，新大陆灵长类通常不具有三色视觉。新大陆大多数灵长类动物独特的视觉系统所依据的遗传机制允许一些雌性拥有三色视觉，而其他雌性(以及所有雄性)则无法在视觉上区分红色和绿色。已经假设三色个体在绿色背景下能够更好地检测水果，然而也假设二色个体更有能力检测隐秘的伪装物体。这项研究项目将通过比较在野生松鼠猴子种群中收集的关于觅食和躲避捕食者的行为数据与研究种群中所有焦点动物的色觉状态的遗传数据来评估这些假设，这些遗传数据是通过使用从非侵入性收集的粪便样本中提取的DNA对它们的X连锁视蛋白等位基因进行基因分析而收集的。此外，在收集行为数据的同时，研究人员将通过在喂养平台上进行一系列实验来进一步探索个体颜色视觉状态变化的意义，这些实验旨在解决动物在解决觅食问题和检测捕食者方面的使用。这项研究是对野生灵长类动物群体进行的首批全面行为遗传学研究之一。该项目的智力价值在于，它将在野外条件下测试几个明确的假设，这些假设涉及三色和双色视觉对于解决觅食问题和避免捕食可能的适应性意义，目的是让研究界更接近于解释为什么颜色视觉多态在大多数白颈鹿血统中保持了如此长的一段时间。这些数据还将被用来更好地理解灵长类动物颜色视觉的分子进化。这项研究的更广泛影响是，它将有助于厄瓜多尔Tiputini生物多样性站正在进行的关于共处亚马逊地区的亚马逊灵长类动物比较行为生物学的长期调查，并帮助保护亚马逊森林地区的努力。此外，它将促进皮蒙塔古联合研究员的专业发展和研究生培训，他将有助于培训纽约大学分子人类学实验室的其他研究生和本科生，并将使皮蒙塔古联合研究员在实地期间与厄瓜多尔和其他热带生物学国际专家进行专业互动。

The goal of this project is to investigate intraspecific variation in the color vision system of South American squirrel monkeys (Saimiri sciureus), a model taxon of New World primate (Platyrrhini). Unlike African and Asian primates, New World primates do not routinely possess trichromatic color vision. The genetic mechanisms that underlie the unique visual systems of most New World primate genera allow some females to possess trichromatic vision while other females (and all males) cannot visually differentiate red from green. It has been hypothesized that trichromatic individuals are better equipped to detect fruit against a green background, yet it has also been hypothesized that dichromatic individuals are more capable of detecting cryptic, camouflaged objects. This research project will evaluate these hypotheses by comparing behavioral data on foraging and predator avoidance collected on a wild population of squirrel monkeys with genetic data on the color vision status of all focal animals within the study population gleaned from genotyping their X-linked opsin alleles using DNA extracted from non-invasively collected fecal samples. Additionally, while collecting behavioral data, the investigators will further explore the significance of individual variation in color vision status through a series of experiments at feeding platforms that are designed to address the animals' use of color cues in solving foraging problems and detecting predators.This study represents one of the first comprehensive behavioral genetic studies undertaken with a wild population of primates. The intellectual merit of the project is that it will test, under wild conditions, several explicit hypotheses concerning the possible adaptive significance of trichromatic versus dichromatic color vision for solving foraging problems and for avoiding predation, with the aim of bringing the research community closer to an explanation as to why color vision polymorphism has been maintained over such a long period of time among most platyrrhine lineages. These data will also be used to better understand the molecular evolution of primate color vision.The broader impact of this study is that it will contribute to an ongoing long-term investigation on the comparative behavioral biology of sympatric Amazonian primates at the Tiputini Biodiversity Station in Ecuador run by co-PI Di Fiore and assist in efforts at protecting forested areas in the Amazon. Additionally, it will foster the professional development and graduate training of co-PI Montague, who will be instrumental in training other graduate students and undergraduates in New York University's Molecular Anthropology Laboratory, and it will provide for co-PI Montague's professional interaction with Ecuadorian and other international experts in tropical biology while in the field.