Loudon James E, Grobler J Paul, Sponheimer Matt, Moyer Kimberly, Lorenz Joseph G, Turner Trudy R
Department of Anthropology, East Carolina University, Greenville, North Carolina, United States of America; Department of Anthropology, University of Colorado, Boulder, Boulder, Colorado, United States of America.
Department of Genetics, University of the Free State, Bloemfontein, South Africa.
PLoS One. 2014 Jul 10;9(7):e100758. doi: 10.1371/journal.pone.0100758. eCollection 2014.
This study seeks to understand how humans impact the dietary patterns of eight free-ranging vervet monkey (Chlorocebus pygerythrus) groups in South Africa using stable isotope analysis. Vervets are omnivores that exploit a wide range of habitats including those that have been anthropogenically-disturbed. As humans encroach upon nonhuman primate landscapes, human-nonhuman primate interconnections become increasingly common, which has led to the rise of the field of ethnoprimatology. To date, many ethnoprimatological studies have examined human-nonhuman primate associations largely in qualitative terms. By using stable carbon (δ13C) and nitrogen (δ15N) isotope analysis, we use quantitative data to understand the degree to which humans impact vervet monkey dietary patterns. Based on initial behavioral observations we placed the eight groups into three categories of anthropogenic disturbance (low, mid, and high). Using δ13C and δ15N values we estimated the degree to which each group and each anthropogenically-disturbed category was consuming C4 plants (primarily sugar cane, corn, or processed foods incorporating these crops). δ13C values were significantly different between groups and categories of anthropogenic-disturbance. δ15N values were significantly different at the group level. The two vervet groups with the highest consumption of C4 plants inhabited small nature reserves, appeared to interact with humans only sporadically, and were initially placed in the mid level of anthropogenic-disturbance. However, further behavioral observations revealed that the high δ13C values exhibited by these groups were linked to previously unseen raiding of C4 crops. By revealing these cryptic feeding patterns, this study illustrates the utility of stable isotopes analysis for some ethnoprimatological questions.
本研究旨在通过稳定同位素分析，了解人类如何影响南非八个自由放养的黑长尾猴（Chlorocebus pygerythrus）群体的饮食模式。黑长尾猴是杂食动物，利用包括受人为干扰的栖息地在内的广泛栖息地。随着人类侵入非人类灵长类动物的领地，人类与非人类灵长类动物的相互联系变得越来越普遍，这导致了人类灵长类学领域的兴起。迄今为止，许多人类灵长类学研究主要从定性角度研究人类与非人类灵长类动物的关联。通过使用稳定碳（δ13C）和氮（δ15N）同位素分析，我们利用定量数据来了解人类对黑长尾猴饮食模式的影响程度。基于初步的行为观察，我们将这八个群体分为三类人为干扰（低、中、高）。利用δ13C和δ15N值，我们估计了每个群体和每个人为干扰类别消耗C4植物（主要是甘蔗、玉米或含有这些作物的加工食品）的程度。不同群体和人为干扰类别之间的δ13C值存在显著差异。在群体层面，δ15N值存在显著差异。C4植物消耗量最高的两个黑长尾猴群体栖息在小型自然保护区，似乎只是偶尔与人类互动，最初被归为人为干扰的中级水平。然而，进一步的行为观察表明，这些群体表现出的高δ13C值与以前未见过的对C4作物的掠夺有关。通过揭示这些隐秘的觅食模式，本研究说明了稳定同位素分析在一些人类灵长类学问题上的实用性。
