美国《公共科学图书馆·综合》(PLoS ONE)3月10日刊出的一份研究报告说,母猴能教幼猴用工具刷牙。
日本京都大学灵长类研究所教授正高信男带领研究小组,对泰国中部一处寺院附近的大约250只野生食蟹猴进行了一个月观察。当地人介绍说,这个猴群中的一些猴子可能从10年前就会用捡到的人类头发当牙线,清洁牙齿缝隙。
研究小组将猴群中的7只母猴作为特殊观察目标,计算它们将头发放入口中的次数和摩擦牙齿的时间。结果发现,当幼猴在眼前时,母猴将头发放入嘴里的次数比平时多一倍,用头发摩擦牙齿的时间更长,且动作幅度更夸张。
研究小组指出,这是首次在野生猴群中发现雌性教后代使用工具。
正高信男说,研究人员对“幼猴会盯着母亲刷牙的动作”感到吃惊,今后将继续跟踪观察母猴“刷牙教育”的效果如何。
研究人员说,之前有研究发现,幼年大猩猩和日本猕猴分别会用草从蚁穴中钓白蚁、在海水里清洗土豆,但这些行为通常被认为是幼崽简单模仿母亲的动作。(生物谷Bioon.com)
生物谷推荐原始出处:
PLoS ONE 4(3): e4768. doi:10.1371/journal.pone.0004768
Free-Ranging Macaque Mothers Exaggerate Tool-Using Behavior when Observed by Offspring
Nobuo Masataka1*, Hiroki Koda1, Nontakorn Urasopon2¤, Kunio Watanabe1
1 Primate Research Institute, Kyoto University, Inuyama, Japan, 2 Department of Animal Science, Faculty of Agriculture, Ubon Rajathanee University, Bangkok, Thailand
The population-level use of tools has been reported in various animals. Nonetheless, how tool use might spread throughout a population is still an open question. In order to answer that, we observed the behavior of inserting human hair or human-hair-like material between their teeth as if they were using dental floss in a group of long-tailed macaques (Macaca fascicularis) in Thailand. The observation was undertaken by video-recording the tool-use of 7 adult females who were rearing 1-year-old infants, using the focal-animal-sampling method. When the data recorded were analyzed separately according to the presence/absence of the infant of the target animal in the target animal's proximity, the pattern of the tool-using action of long-tailed adult female macaques under our observation changed in the presence of the infant as compared with that in the absence of the infant so that the stream of tool-using action was punctuated by more pauses, repeated more often, and performed for a longer period during each bout in the presence of the infant. We interpret this as evidence for the possibility that they exaggerate their action in tool-using so as to facilitate the learning of the action by their own infants.