Primate behavior is influenced by both heritable factors and environmental experience during development. Previous studies of rhesus macaques (Macaca mulatta) examined the effects of genetic variation on expressed behavior and related neurobiological traits (heritability and/or genetic association) using a variety of study designs. Most of these prior studies examined genetic effects on the behavior of adults or adolescent rhesus macaques, not in young macaques early in development. To assess environmental and additive genetic variation in behavioral reactivity and response to novelty among infants, we investigated a range of behavioral traits in a large number (N = 428) of pedigreed infants born and housed in large outdoor corrals at the Oregon National Primate Research Center (ONPRC). We recorded the behavior of each subject during a series of brief tests, involving exposure of each infant to a novel environment, to a social threat without the mother present, and to a novel environment with its mother present but sedated. We found significant heritability (h2) for willingness to move away from the mother and explore a novel environment (h2 = 0.25 ± 0.13; P = 0.003). The infants also exhibited a range of heritable behavioral reactions to separation stress or to threat when the mother was not present (h2 = 0.23 ± 0.13–0.24 ± 0.15, P < 0.01). We observed no evidence of maternal environmental effects on these traits. Our results extend knowledge of genetic influences on temperament and reactivity in nonhuman primates by demonstrating that several measures of behavioral reactivity among infant rhesus macaques are heritable.

中文翻译：

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婴儿恒河猴（Macaca mulatta）在三个行为评估中对新奇和其他刺激的反应的定量遗传学

灵长类动物的行为受遗传因素和发育过程中环境经验的影响。先前对恒河猴（Macaca mulatta）的研究使用各种研究设计检查了遗传变异对表达行为和相关神经生物学特征（遗传力和/或遗传关联）的影响。这些先前的大多数研究都检查了遗传对成年或青春期恒河猴行为的影响，而不是在发育早期的年轻猕猴中。为了评估婴儿行为反应性和对新奇事物的反应的环境和加性遗传变异，我们调查了大量 (N = 428) 出生和居住在俄勒冈国家灵长类动物研究中心大型户外畜栏的纯种婴儿的一系列行为特征(ONPRC)。我们在一系列简短的测试中记录了每个受试者的行为，包括将每个婴儿暴露于一个新环境、一个没有母亲在场的社会威胁，以及一个母亲在场但被镇静的新环境。我们发现远离母亲并探索新环境的意愿具有显着的遗传力（h2）（h2 = 0.25 ± 0.13；P = 0.003）。当母亲不在场时，婴儿还对分离压力或威胁表现出一系列可遗传的行为反应（h2 = 0.23 ± 0.13–0.24 ± 0.15，P < 0.01）。我们没有观察到母亲环境对这些特征的影响的证据。我们的研究结果通过证明婴儿恒河猴的几种行为反应性测量是可遗传的，扩展了对非人类灵长类动物气质和反应性的遗传影响的知识。