title: Influence of the task on hand preference: individual differences among gorillas (Gorilla gorilla gorilla).
abstract: The degree of task complexity and bimanual complementarity have been proposed as factors affecting lateralization strength in humans. However, a large number of studies have demonstrated group-level lateral hand bias for different manual activities in numerous non-human primate species. However, no study has tested the effects that a variety of tasks may have in inducing differences in hand preference. Here, we aim to test if 3 adult gorillas exhibited a greater hand preference bias performing 4 tasks of varying complexity: grasping small versus large foods, proto-tool use task and tool use task involving greater visuospatial requirements. We found that (1) the complexity of the task does not necessarily induce a right-handed bias and (2) a subject can be right-handed for a complex task and left-handed for another one. These results, complemented by many publications on hand preference in non-human primates, reveal a great variability in hand preference, which makes it very difficult to deduce any details of hominin handedness with artefacts.
authors.affiliation: Handibio EA 4322, Université du Sud Toulon-Var, La Garde, France. pouydeba@univ-tln.fr
authors.forename: E
authors.initials: E
authors.lastname: Pouydebat
authors.forename: E
authors.initials: E
authors.lastname: Reghem
authors.forename: P
authors.initials: P
authors.lastname: Gorce
authors.forename: V
authors.initials: V
authors.lastname: Bels
mesh_terms: D000818:Animals; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006071:Gorilla gorilla / Q000502:physiology*; D008297:Male; D011597:Psychomotor Performance / Q000502:physiology*