Hand preference for a bimanual task in tufted capuchins (Cebus apella) and rhesus macaques (Macaca mulatta).

Abstract

This research examined hand preference for a bimanual task in 45 tufted capuchin (Cebus apella) and 55 rhesus macaque (Macaca mulatta) monkeys. Investigators presented subjects with plastic tubes lined with food and noted which hand the animals used to hold the tubes and which hand the animals used to remove the food. Several significant findings emerged from this investigation. First, rhesus macaques, but not tufted capuchins, exhibited a population-level bias toward use of the right hand (although the difference in direction of hand preference between species was not significant). Second, capuchins exhibited greater hand preference strength than did macaques. Third, among capuchins, but not among macaques, hand preference strength was greater for adults than for immatures. Finally, both species used their index digit to remove food most frequently when compared with other digits. Findings of hand preference direction and strength in this study were compared with other findings noted for chimpanzees which performed a bimanual tube task in a previous study. The authors conclude that using the same procedure to compare hand preference across species represents a powerful research tool that can lead to a more complete understanding of the evolution and ontogenesis of primate handedness.

The use of bouts and frequencies in the evaluation of hand preferences for a coordinated bimanual task in chimpanzees (Pan troglodytes): An empirical study comparing two different indices of laterality.

“…Thus, data from Studies that McGrew and Marchant (1997) viewed as lacking sufficient control over independence of observations were excluded from their analysis and led them to conclude that there was no convincing evidence of population-level hand preference in nonhuman primates. This conclusion stands in strong contrast to other published interpretations of most of the same data and literature (Bradshaw & Rogers, 1993;Hopkins, 1996Hopkins, ,1999bWard & Hopkins, 1993;Westergaard, Kuhn, & Suomi, 1998;Westergaard & Suomi, 1996).Unfortunately, most of these arguments are theoretical rather than based on solid, empirical data because there has been no attempt to quantify and compare hand preference findings using both bouts and frequencies as the level of analysis in the evaluation of hand preference. The primary purpose of this study was to assess hand preference for a coordinated bimanual tube task (TUBE), referred to as the TUBE task, using both bouts and frequencies in a sample of chimpanzees.…”

Manual Specialisation and Tool Use in Captive Chimpanzees ( Pan troglodytes ): The Effect of Unimanual and Bimanual Strategies on Hand Preference

“…For example, chimpanzees required to hold a tube and extract peanut butter with fingers of the opposite hand exhibited a population right hand bias (Hopkins, 1995). Westergaard and Suomi (1996) have reported a similar population right hand bias in rhesus monkeys but not capuchin monkeys (also see Beck & Barton, 1972) for the same tube task. Finally, Byrne and Byrne (1991) found a slight but significant right hand population bias in bimanual feeding in wild gorillas (also see Fagot & Vauclair, 1988).…”

Hand use by tufted capuchins (Cebus apella) to extract a small food item from a tube: digit movements, hand preference, and performance

“…However, current data indicate that hand-preference measures can be biased by several variables, such as the postural demands in performing specific activities, the number of actions involved in solving a specific task, and the need to use both hands simultaneously to execute a particular motor pattern [Harrison & Byrne, 2000;Hopkins, 1993Hopkins, , 1995Hopkins & Rabinowitz, 1997;McGrew & Marchant, 1997;Spinozzi et al, 1998;Spinozzi & Truppa, 1999, 2002Westergaard et al, 1997Westergaard et al, , 1998Westergaard & Suomi, 1996]. For example, data from capuchins show that reaching actions involving the complementary use of hands for food retrieval elicit a significant hand bias at the group level, while coordinated-bimanual tasks involving a sequence of problem-solving actions induce strong individual hand preferences.…”