Laboratory of Auditory Neurophysiology, Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
J Exp Biol. 2011 Nov 1;214(Pt 21):3619-29. doi: 10.1242/jeb.056101.
The natural environment is inherently noisy with acoustic interferences. It is, therefore, beneficial for a species to modify its vocal production to effectively communicate in the presence of interfering noises. Non-human primates have been traditionally considered to possess limited voluntary vocal control, but little is known about their ability to modify vocal behavior when encountering interfering noises. Here we tested the ability of the common marmoset (Callithrix jacchus) to control the initiation of vocalizations and maintain vocal interactions between pairs in an acoustic environment in which the length and predictability (periodic or random aperiodic occurrences) of interfering noise bursts were varied. Despite the presence of interfering noise, the marmosets continued to engage in antiphonal calling behavior. Results showed that the overwhelming majority of calls were initiated during silence gaps even when the length of the silence gap following each noise burst was unpredictable. During the periodic noise conditions, as the length of the silence gap decreased, the latency between the end of noise burst and call onset decreased significantly. In contrast, when presented with aperiodic noise bursts, the marmosets chose to call predominantly during long (4 and 8 s) over short (2 s) silence gaps. In the 8 s periodic noise conditions, a marmoset pair either initiated both calls of an antiphonal exchange within the same silence gap or exchanged calls in two consecutive silence gaps. Our findings provide compelling evidence that common marmosets are capable of modifying their vocal production according to the dynamics of their acoustic environment during vocal communication.
自然环境中存在着固有噪声和声学干扰。因此，对于一个物种来说，能够在存在干扰噪声的情况下调整其发声以进行有效交流是有益的。传统上认为非人类灵长类动物对声音的控制能力有限，但对于它们在遇到干扰噪声时调整发声行为的能力却知之甚少。在这里，我们测试了普通狨猴（Callithrix jacchus）在声学环境中控制发声起始并维持对发声的相互作用的能力，在该环境中，干扰噪声突发的长度和可预测性（周期性或随机非周期性出现）发生变化。尽管存在干扰噪声，但狨猴仍继续进行对呼叫声。结果表明，尽管存在干扰噪声，狨猴仍会在沉默间隙中发出压倒性多数的叫声，即使在每次噪声突发后沉默间隙的长度不可预测。在周期性噪声条件下，随着沉默间隙长度的减小，噪声突发结束和叫声起始之间的潜伏期显著降低。相比之下，当出现非周期性噪声突发时，狨猴主要选择在较长（4 和 8 s）的沉默间隙而不是较短（2 s）的沉默间隙中进行叫声。在 8 s 的周期性噪声条件下，一对狨猴要么在同一个沉默间隙中同时发出对呼叫声，要么在两个连续的沉默间隙中交换叫声。我们的发现提供了有力的证据，表明普通狨猴能够根据其在发声交流期间的声学环境动态来调整其发声。
