Hand biomechanics during simulated stone tool use

Animal stone-handling behavior (SH) has been recorded in detail only in primates, mainly across macaque species. The purpose(s) of SH are still unknown, yet various hypotheses have been suggested, including that it is a misdirected behavior when hungry and/or a play behavior that aids individuals' motor and stone tool-use development. SH has also been observed across both wild and captive otter species, but no overview report of the extent of this behavior across otter species has been published yet. To fill this gap in the literature, we contacted wild and captive otter researchers and keepers to enquire directly on SH in the species they work with. We accepted anecdotal reports in this first review of the behavior. Using the reports and anecdotes thus obtained, we compiled the first list of otter species that show SH. We found that most (10 out of 13) of currently known otter species practice SH. Therefore, similarly to macaques, SH is also common in otters and occurs in the majority of species. Future studies should focus on replicating these findings and further investigating the potential functions and selection pressures of SH in otters and other animal species.

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Habitual Stone-Tool Aided Extractive Foraging in White-Faced Capuchins, Cebus Capucinus

10.1101/351619 ◽

2018 ◽

Author(s):

Brendan J Barrett ◽

Claudio M Monteza-moreno ◽

Tamara DOGANDŽIĆ ◽

Nicolas Zwyns ◽

Alicia IBÁÑEZ ◽

...

Keyword(s):

Tool Use ◽

National Park ◽

Resource Limitation ◽

Stone Tools ◽

Cebus Capucinus ◽

Hermit Crabs ◽

Stone Tool ◽

Extractive Foraging ◽

First Case ◽

One Year

ABSTRACTHabitual reliance on tool use is a marked behavioral difference between wild robust (genus Sapajus) and gracile (genus Cebus) capuchin monkeys. Despite being well studied and having a rich repertoire of social and extractive foraging traditions, Cebus sp have rarely been observed engaging in tool use and have never been reported to use stone tools. In contrast, habitual tool use and stone-tool use by Sapajus is widespread. We discuss factors which might explain these differences in patterns of tool use between Cebus and Sapajus. We then report the first case of habitual stone-tool use in a gracile capuchin: a population of white-faced capuchins (Cebus capucinus imitator) in Coiba National Park, Panama who habitually rely on hammerstone and anvil tool use to access structurally protected food items in coastal areas including Terminalia catappa seeds, hermit crabs, marine snails, terrestrial crabs, and other items. This behavior has persisted on one island in Coiba National Park since at least 2004. From one year of camera trapping, we found that stone tool use is strongly male-biased. Of the 205 unique camera-trap-days where tool use was recorded, adult females were never observed to use stone-tools, although they were frequently recorded at the sites and engaged in scrounging behavior. Stone-tool use occurs year-round in this population, and over half of all identifiable individuals were observed participating. At the most active tool use site, 83.2% of days where capuchins were sighted corresponded with tool use. Capuchins inhabiting the Coiba archipelago are highly terrestrial, under decreased predation pressure and potentially experience resource limitation compared to mainland populations– three conditions considered important for the evolution of stone tool use. White-faced capuchin tool use in Coiba National Park thus offers unique opportunities to explore the ecological drivers and evolutionary underpinnings of stone tool use in a comparative within- and between-species context.

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There Is More than One Way to Crack an Oyster: Identifying Variation in Burmese Long-Tailed Macaque (Macaca fascicularis aurea) Stone-Tool Use

PLoS ONE ◽

10.1371/journal.pone.0124733 ◽

2015 ◽

Vol 10 (5) ◽

pp. e0124733 ◽

Cited By ~ 21

Author(s):

Amanda Tan ◽

Say Hoon Tan ◽

Dhaval Vyas ◽

Suchinda Malaivijitnond ◽

Michael D. Gumert

Keyword(s):

Tool Use ◽

Macaca Fascicularis ◽

Stone Tool

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Habitual stone-tool-aided extractive foraging in white-faced capuchins, Cebus capucinus

Royal Society Open Science ◽

10.1098/rsos.181002 ◽

2018 ◽

Vol 5 (8) ◽

pp. 181002 ◽

Cited By ~ 13

Author(s):

Brendan J. Barrett ◽

Claudio M. Monteza-Moreno ◽

Tamara Dogandžić ◽

Nicolas Zwyns ◽

Alicia Ibáñez ◽

...

Keyword(s):

Tool Use ◽

National Park ◽

Resource Limitation ◽

Stone Tools ◽

Cebus Capucinus ◽

Hermit Crabs ◽

Stone Tool ◽

Extractive Foraging ◽

Marine Snails ◽

First Case

Habitual reliance on tool use is a marked behavioural difference between wild robust (genus Sapajus ) and gracile (genus Cebus ) capuchin monkeys. Despite being well studied and having a rich repertoire of social and extractive foraging traditions, Cebus sp. rarely use tools and have never been observed using stone tools. By contrast, habitual tool use by Sapajus is widespread. We review theory and discuss factors which might explain these differences in patterns of tool use between Cebus and Sapajus . We then report the first case of habitual stone tool use in a gracile capuchin: a population of white-faced capuchins ( Cebus capucinus imitator ) in Coiba National Park, Panama who habitually rely on hammerstone and anvil tool use to access structurally protected food items in coastal areas including Terminalia catappa seeds, hermit crabs, marine snails, terrestrial crabs and other items. This behaviour has persisted on one island in Coiba National Park since at least 2004. From 1 year of camera trapping, we found that stone tool use is strongly male-biased. Of the 205 camera trap days where tool use was recorded, adult females were never observed to use stone tools, although they were frequently recorded at the sites and engaged in scrounging behaviour. Stone tool use occurs year-round in this population; over half of all identifiable individuals were observed participating. At the most active tool use site, 83.2% of days where capuchins were sighted corresponded with tool use. Capuchins inhabiting the Coiba archipelago are highly terrestrial, under decreased predation pressure and potentially experience resource limitation compared to mainland populations—three conditions considered important for the evolution of stone tool use. White-faced capuchin tool use in Coiba National Park thus offers unique opportunities to explore the ecological drivers and evolutionary underpinnings of stone tool use in a comparative within- and between-species context.

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