Stone‐tool usage by Thai long‐tailed macaques (Macaca fascicularis)

Abstract

In January and March of 2005, we conducted surveys of long-tailed macaques at Piak Nam Yai Island, Laem Son National Park (9 degrees N 34-35', 98 degrees E 28'), Ranong Province, situated in southern Thailand. Two of the three troops of long-tailed macaques found on the island were observed using axe-shaped stones to crack rock oysters, detached gastropods (Thais tissoti, Petit, 1852), bivalves (Gafrarium divaricatum, Gmelin, 1791), and swimming crabs (Thalamita danae, Stimpson, 1858). They smashed the shells with stones that were held in either the left or right hand, while using the opposite hand to gather the oyster meat. Some monkeys used both hands to handle the stones. According to Matsuzawa's 1996 hierarchical classification of tool usage (levels 0-3), the tool usage by Thai long-tailed macaques could be characterized as either level 1 (cracking rock oysters with stones) or level 2 (cracking drifting mollusks and crabs with stones by placing them on a rock). Our discovery of stone-tool usage by Thai long-tailed macaques provides a new point of reference for discussions regarding the evolution of tool usage and the material culture of primates.

The origins and persistence of Homo floresiensis on Flores: biogeographical and ecological perspectives

“…They had brains not much larger than those of chimpanzees yet developed stone tools' (Wilson, 2012: 15), but it should be pointed out that large numbers of animals are tool users -creating nests, webs and traps as well as artefacts (Hansell and Ruxton, 2007). That the use of stones for resource procurement can be innovated independently in the wild is seen in the tool using of capuchins from Brazil (Fragaszy et al, 2004), long-tailed macaques from Thailand (Malaivijitnond et al, 2007;Gumert and Malaivijitnond, 2012) and chimpanzees from West Africa (Boesch and Boesch, 1990;Mercader et al, 2002), in addition to sea otters (Hall and Schaller, 1964) and vultures (Thouless et al, 1989). While the development of a knapped stone tool technology is unlikely to have been independently developed by H. floresiensis, it is certainly possible that such tool-making might be conserved, even during brain reduction, as it is an important part of resource procurement for hominins from ~2.6 Ma onwards (Semaw et al, 2003).The immense conservatism of early Palaeolithic stone tool assemblages indicates that the maintenance of an existing tradition is far more deeply-rooted than the ability to innovate -as shown by the continuity in hand-axe forms over the thousands of millennia of the Acheulean.…”

Patterns of Water Use in Primates

“…The splash displays of P. troglodytes and G. gorilla involve striking projectiles (objects or body parts) against a water source, both examples which involve novel tool use behaviour compared to traditional dominance displays. Percussive technology also has a link to aquatic environment use in C. apella , where one individual used a hammer stone to open oyster shells for food [Fernandes, 1991] and in M. fascicularis where several individuals in two groups in Thailand used rocks to access gastropods, bivalves and crabs [Malaivijitnond et al, 2007]. A similar technology is used by both capuchins [Liu et al, 2008] and P. troglodytes [Sakura and Matsuzawa, 1991] in nut cracking behaviours, which has been used in modelling and attempting to identify early hominin percussive technology [Mercader et al, 2002].…”

“…Spawning season for fish and seasonal drying of lakes make aquatic foods more easily attainable at times when terrestrial resources are becoming more limited, and so offers an important source of additional nutrition and energy during times of terrestrial food scarcity [Stewart, 1994]. In the case of M. fascicularis , a primarily frugivorous species, it is a species-wide pattern to rely on other food types, including aquatic fauna, when fruit is scarce [Yeager, 1996;Malaivijitnond et al, 2007]. In other species, some populations use aquatic resources during seasons of scarcity while others do not.…”

Organização sequencial e otimização do comportamento na quebra de frutos encapsulados por macacos-prego (Sapajus sp.) em semi-liberdade

“…A única espécie observada usando ferramentas, para forrageio em vida livre é a dos macacos cinomolgos, Macaca fascicularis. Malaivijitnond et al (2007) observaram grupos destes animais utilizando pedras para destacar gastrópodes e bivalves do substrato e esmagar suas conchas.…”