Gumert Michael D, Kluck Marius, Malaivijitnond Suchinda
Division of Psychology, School of Humanities and Social Sciences, Nanyang Technological University, Singapore, Singapore.
Am J Primatol. 2009 Jul;71(7):594-608. doi: 10.1002/ajp.20694.
Stone hammering in natural conditions has been extensively investigated in chimpanzees and bearded capuchins. In contrast, knowledge of stone tool use in wild Old World monkeys has been limited to anecdotal reports, despite having known for over 120 years that Macaca fascicularis aurea use stone tools to process shelled foods from intertidal zones on islands in the Andaman Sea. Our report is the first scientific investigation to look at the stone tools used by these macaques. We observed they were skilled tool users and used stone tools daily. They selected tools with differing qualities for differing food items, and appeared to use at least two types of stone tools. Pounding hammers were used to crush shellfish and nuts on anvils and axe hammers were used to pick or chip at oysters attached to boulders or trees. We found significant physical differences between these two tools. Tools at oyster beds were smaller and exhibited scarring patterns focused more often on the points, whereas tools found at anvils were larger and showed more scarring on the broader surfaces. We also observed grip differences between the two tool types. Lastly, macaques struck targets with axe hammers more rapidly and over a wider range of motion than with pounding hammers. Both our behavioral and lithic data support that axe hammers might be used with greater control and precision than pounding hammers. Hand-sized axe hammers were used for controlled chipping to crack attached oysters, and larger pounding hammers were used to crush nuts and unattached shellfish on anvils. In addition to stones, they also used hand-sized auger shells (Turritella attenuata) as picks to axe attached oysters. Pound hammering appears similar to the stone tools used by chimpanzees and capuchins, but axe hammering has not yet been documented in other nonhuman primates in natural conditions.
在自然条件下，黑猩猩和卷尾猴使用石锤的行为已得到广泛研究。相比之下，尽管早在120多年前就已知道安达曼海岛屿上的食蟹猕猴会使用石器处理潮间带的带壳食物，但对野生旧世界猴使用石器的了解仍仅限于轶事报道。我们的报告是对这些猕猴使用的石器进行的首次科学调查。我们观察到它们是熟练的工具使用者，并且每天都使用石器。它们针对不同的食物选择不同质量的工具，并且似乎使用至少两种类型的石器。捣锤用于在砧石上碾碎贝类和坚果，斧锤则用于采摘或敲开附着在巨石或树上的牡蛎。我们发现这两种工具在物理特征上存在显著差异。牡蛎床处的工具较小，疤痕模式更多集中在尖端，而在砧石处发现的工具较大，在更宽的表面上有更多疤痕。我们还观察到两种工具类型在握持方式上的差异。最后，猕猴用斧锤敲击目标的速度更快，动作范围也比用捣锤时更广。我们的行为数据和石器数据均支持，斧锤可能比捣锤使用起来更具控制性和精确性。手掌大小的斧锤用于有控制地敲碎附着的牡蛎，而较大的捣锤则用于在砧石上碾碎坚果和未附着的贝类。除了石头，它们还使用手掌大小的钻螺壳（Turritella attenuata）作为采摘工具来敲开附着的牡蛎。捣锤行为似乎与黑猩猩和卷尾猴使用的石器相似，但斧锤行为在自然条件下尚未在其他非人类灵长类动物中得到记录。
