Hand preference in unimanual and bimanual coordinated tasks in wild western lowland gorillas (Gorilla gorilla gorilla) feeding on African ginger (Zingiberaceae).
African ginger
bimanual task
great apes
hand preference
western lowland gorilla
Journal
American journal of physical anthropology
ISSN: 1096-8644
Titre abrégé: Am J Phys Anthropol
Pays: United States
ID NLM: 0400654
Informations de publication
Date de publication:
07 2021
07 2021
Historique:
revised:
24
12
2020
received:
20
06
2020
accepted:
28
12
2020
pubmed:
12
1
2021
medline:
26
10
2021
entrez:
11
1
2021
Statut:
ppublish
Résumé
Bimanual coordinated behaviors are critical for detecting robust individual hand preference in nonhuman primates but are particularly challenging to observe in the wild. This study focuses on spontaneous feeding behavior on African ginger (Aframomum sp. and Renealmia sp.), which involves a unimanual task (reaching and pulling out a ginger stem) and a bimanual coordinated task (extracting pith from a ginger stem) by wild western lowland gorillas. Study subjects were 21 gorillas in the Moukalaba-Doudou National Park, Gabon. We examined whether they exhibit significant hand preference at the individual and group levels for both tasks. Sixteen gorillas showed significant hand preference in the unimanual task, whereas all 21 individuals showed significant hand preference in the bimanual coordinated task. Hand preference was significantly stronger in the bimanual coordinated task than in the unimanual task. It is noteworthy that gorillas showed a significant right-hand preference at the group level for the bimanual task (roughly 70% of the subjects). This study confirmed that bimanual coordinated tasks are more sensitive in detecting hand preferences in nonhuman primates. In addition to the bimanual nature of the task, the precision grip for processing and the importance of African ginger as a food resource might influence the expression of hand preference. Evidence of a group-level right-hand preference may support the "postural origins theory." Because all wild African great apes feed on the pith of African ginger, comparing this task and its hand preferences can contribute toward a better understanding of the evolution of handedness in Hominidae.
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
531-545Informations de copyright
© 2021 Wiley Periodicals LLC.
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