Supplementary Material for: Validation of a Noninvasive Hair Trapping Method for Extractive-Foraging Primates

Hair is a useful source of biological information. For example, the bulb can be a source of high-quality genetic material, whereas the shaft can be useful for measuring heavy metals and some hormones, such as cortisol. The stable isotope composition of hair is another valuable source of biological information. Consequently, noninvasive methods of hair sampling have become important research tools. Several hair-trapping methods have been developed for use on mammals, but these are rarely deployed on primates in part because their travel patterns can be difficult to predict and because many species are averse to novel objects in their environments. Yet if a species has a natural propensity to envision, manipulate, and withdraw extractable food resources, then a baited receptacle lined with double-sided tape may prove successful as a hair trap. Recently, researchers demonstrated the success of such a contraption with tufted capuchins, a Neotropical monkey species with a high degree of somatosensory intelligence and a proclivity for extractive foraging. Here, we replicate this method in a population of tool-using long-tailed macaques (Macaca fascicularis). Our trials validate the effectiveness of the method, suggesting that it is suitable for long-tailed macaques and other extractive-foraging primates.

毛发是一类重要的生物信息来源。例如，毛球（hair bulb）可作为高质量遗传物质的提取来源，而毛干（hair shaft）则可用于检测重金属及皮质醇（cortisol）等激素水平。毛发的稳定同位素组成（stable isotope composition）亦是极具价值的生物信息来源。因此，无创毛发采样方法已成为重要的研究工具。目前已开发出多种适用于哺乳类动物的毛发采集方法，但这类方法极少应用于灵长类动物，部分原因在于灵长类的活动路径难以预测，且多数物种对环境中的新奇物体存在排斥心理。但若某一物种天生具备预判、操作并获取可提取食物资源的能力，那么在贴有双面胶带的诱饵容器中设置毛发采集装置（hair trap），便可取得良好的采集效果。近期有研究者以簇绒卷尾猴（tufted capuchins）——一种栖息于新热带区（Neotropical）、具备高度体感智能（somatosensory intelligence）且擅长提取式觅食（extractive foraging）的猴类物种——为对象，验证了该装置的采集效果。本研究在使用工具的长尾猕猴（Macaca fascicularis）种群中复刻了该方法，试验结果验证了该方法的有效性，表明其适用于长尾猕猴及其他具备提取式觅食习性的灵长类动物。