In addition, contextual, postural and situational factors can also influence hand preference ( MacNeilage et al., 1987 Olson et al., 1990 Lehman, 1993 De Vleeschouwer et al., 1995). Several review articles on the topic have come to different conclusions ( McGrew & Marchant, 1997 Hopkins & Cantalupo, 2005 Papademetriou et al., 2005), but one common theme is that hand preferences in nonhuman primates are influenced by the different cognitive and motor demands of the tasks. Subsequently, handedness data have been reported in a variety of nonhuman primate species, yet there are conflicting opinions as to whether nonhuman primates exhibit population-level handedness. (1987) who argued that there was some evidence of population-level handedness in nonhuman primates, a view that was at odds with the extant view at that time. The renewed interest in the study of handedness in nonhuman primates was stimulated by the review article by MacNeilage et al. In support of this latter claim is the finding that left hemisphere lateralization for speech is significantly higher among individuals who self-report being right-handed compared to those who report being left-handed ( Rasmussen & Milner, 1977 Knecht et al., 2000 MacNeilage, 2008). With specific reference to handedness, comparative studies of laterality in nonhuman primates are of interest to scientists because a) it has been claimed that population-level handedness is a uniquely human adaptation ( Corballis, 1992 Crow, 2004) and b) some have suggested that handedness is an indirect marker of lateralization for language ( Leask & Crow, 2001 Annett, 2002). In the past 20 years, there has been a plethora of studies on hand preferences and other behavioral manifestations of lateralization in human and nonhuman animals ( Bradshaw & Rogers, 1993 Ward & Hopkins, 1993 Hook-Costigan & Rogers, 1997 Rogers & Andrew, 2002 Papademetriou et al., 2005 Hopkins, 2006 Hopkins, 2007). The overall results neither confirm nor reject previous hypotheses claiming that raising chimpanzees in captivity induces right-handedness, but rather suggest that other factors may account for differences in hand preferences for tool use seen in wild and captive chimpanzees. Lastly, older females performed more slowly on the task compared to younger individuals. We also found that the hand preferences of offspring were significantly positively correlated with the hand preferences of their mothers. No population-level handedness was found for this task however, significant sex differences in preference and performance were found, with males showing greater left handedness and poorer performance compared to females. Here we examined hand preferences and performance on a tool use task designed to simulate termite fishing in a sample of 190 captive chimpanzees to evaluate whether patterns of hand use in captive chimpanzees differed from those observed for wild apes. Previous studies in wild chimpanzees have revealed population-level left handedness for termite fishing. There is continued debate over the factors influencing handedness in captive and wild primates, notably chimpanzees.
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