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Reaching around barriers: the performance of the great apes and 3-5-year-old children.

Vlamings PH, Hare B, Call J - Anim Cogn (2009)

Bottom Line: We compared the inhibitory skills of all great ape species, including 3-5-year-old children in a detour-reaching task, which required subjects to avoid reaching directly for food and instead use an indirect reaching method to successfully obtain the food.As expected older children outperformed younger children.Sanctuary chimpanzees and bonobos outperformed their zoo counterparts whereas there was no difference between the two orangutan samples.

View Article: PubMed Central - PubMed

Affiliation: Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig, Germany.

ABSTRACT
Inhibitory control has been suggested as a key predictive measure of problem-solving skills in human and nonhuman animals. However, there has yet to be a direct comparison of the inhibitory skills of the nonhuman apes and their development in human children. We compared the inhibitory skills of all great ape species, including 3-5-year-old children in a detour-reaching task, which required subjects to avoid reaching directly for food and instead use an indirect reaching method to successfully obtain the food. We tested 22 chimpanzees, 18 bonobos, 18 orangutans, 6 gorillas and 42 children. Our sample included chimpanzees, bonobos and orangutans housed in zoos (N = 27) and others housed in sanctuaries in their native habitats (N = 37). Overall, orangutans were the most skilful apes, including human children. As expected older children outperformed younger children. Sanctuary chimpanzees and bonobos outperformed their zoo counterparts whereas there was no difference between the two orangutan samples. Most zoo chimpanzees and bonobos failed to solve the original task, but improved their performance with additional training, although the training method determined to a considerable extent the level of success that the apes achieved in a transfer phase. In general, the performance of the older children was far from perfect and comparable to some of the nonhuman apes tested.

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Mean percentage (+SEM) of correct trials before and after training as a function of training regime
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Fig4: Mean percentage (+SEM) of correct trials before and after training as a function of training regime

Mentions: Two gorillas failed to learn during training and another one quit responding during testing, and they were dropped from subsequent analyses. Figure 4 presents the percentage of correct trials prior and after training in the remaining subjects. Subjects improved their performance in the test compared to the pretest both in the fixed (Wilcoxon test: Z = 2.41; P = 0.016) and variable condition (Wilcoxon test: Z = 2.54; P = 0.011). Additionally, there were no significant differences in the test between the two training methods (Mann–Whitney test: Z = 0.81; P = 0.42). However, the distribution of responses differed substantially between training regimes. Subjects in the fixed training showed a more restricted distribution of responses with the values clustered around the median (inter-quartile range 50–67%; kurtosis 3.17) whereas subjects in the variable training showed a greater dispersal in their responses (inter-quartile range 12.5–70%; kurtosis 1.04). We found no evidence that either sex (Mann–Whitney test: Z = 0.68; P = 0.50) or age (Spearman r = 0.33; P = 0.20; N = 17) significantly affected performance.Fig. 4


Reaching around barriers: the performance of the great apes and 3-5-year-old children.

Vlamings PH, Hare B, Call J - Anim Cogn (2009)

Mean percentage (+SEM) of correct trials before and after training as a function of training regime
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2822225&req=5

Fig4: Mean percentage (+SEM) of correct trials before and after training as a function of training regime
Mentions: Two gorillas failed to learn during training and another one quit responding during testing, and they were dropped from subsequent analyses. Figure 4 presents the percentage of correct trials prior and after training in the remaining subjects. Subjects improved their performance in the test compared to the pretest both in the fixed (Wilcoxon test: Z = 2.41; P = 0.016) and variable condition (Wilcoxon test: Z = 2.54; P = 0.011). Additionally, there were no significant differences in the test between the two training methods (Mann–Whitney test: Z = 0.81; P = 0.42). However, the distribution of responses differed substantially between training regimes. Subjects in the fixed training showed a more restricted distribution of responses with the values clustered around the median (inter-quartile range 50–67%; kurtosis 3.17) whereas subjects in the variable training showed a greater dispersal in their responses (inter-quartile range 12.5–70%; kurtosis 1.04). We found no evidence that either sex (Mann–Whitney test: Z = 0.68; P = 0.50) or age (Spearman r = 0.33; P = 0.20; N = 17) significantly affected performance.Fig. 4

Bottom Line: We compared the inhibitory skills of all great ape species, including 3-5-year-old children in a detour-reaching task, which required subjects to avoid reaching directly for food and instead use an indirect reaching method to successfully obtain the food.As expected older children outperformed younger children.Sanctuary chimpanzees and bonobos outperformed their zoo counterparts whereas there was no difference between the two orangutan samples.

View Article: PubMed Central - PubMed

Affiliation: Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig, Germany.

ABSTRACT
Inhibitory control has been suggested as a key predictive measure of problem-solving skills in human and nonhuman animals. However, there has yet to be a direct comparison of the inhibitory skills of the nonhuman apes and their development in human children. We compared the inhibitory skills of all great ape species, including 3-5-year-old children in a detour-reaching task, which required subjects to avoid reaching directly for food and instead use an indirect reaching method to successfully obtain the food. We tested 22 chimpanzees, 18 bonobos, 18 orangutans, 6 gorillas and 42 children. Our sample included chimpanzees, bonobos and orangutans housed in zoos (N = 27) and others housed in sanctuaries in their native habitats (N = 37). Overall, orangutans were the most skilful apes, including human children. As expected older children outperformed younger children. Sanctuary chimpanzees and bonobos outperformed their zoo counterparts whereas there was no difference between the two orangutan samples. Most zoo chimpanzees and bonobos failed to solve the original task, but improved their performance with additional training, although the training method determined to a considerable extent the level of success that the apes achieved in a transfer phase. In general, the performance of the older children was far from perfect and comparable to some of the nonhuman apes tested.

Show MeSH