Behavioral Variation in Gorillas: Evidence of Potential Cultural Traits.
The question of whether any species except humans exhibits culture has generated much debate, partially due to the difficulty of providing conclusive evidence from observational studies in the wild. A starting point for demonstrating the existence of culture that has been used for many species including chimpanzees and orangutans is to show that there is geographic variation in the occurrence of particular behavioral traits inferred to be a result of social learning and not ecological or genetic influences. Gorillas live in a wide variety of habitats across Africa and they exhibit flexibility in diet, behavior, and social structure. Here we apply the 'method of exclusion' to look for the presence/absence of behaviors that could be considered potential cultural traits in well-habituated groups from five study sites of the two species of gorillas. Of the 41 behaviors considered, 23 met the criteria of potential cultural traits, of which one was foraging related, nine were environment related, seven involved social interactions, five were gestures, and one was communication related. There was a strong positive correlation between behavioral dissimilarity and geographic distance among gorilla study sites. Roughly half of all variation in potential cultural traits was intraspecific differences (i.e. variability among sites within a species) and the other 50% of potential cultural traits were differences between western and eastern gorillas. Further research is needed to investigate if the occurrence of these traits is influenced by social learning. These findings emphasize the importance of investigating cultural traits in African apes and other species to shed light on the origin of human culture.
Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.
Martha M
MM
Robbins
Kyoto Prefectural University, Graduate School of Life and Environmental Sciences, Kyoto, Japan.
Chieko
C
Ando
Dian Fossey Gorilla Fund International, Atlanta, GA, United States of America.
Katherine A
KA
Fawcett
Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.|School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley (Perth), WA 6009, Australia.
Cyril C
CC
Grueter
Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.
Daniela
D
Hedwig
Kyoto Prefectural University, Graduate School of Life and Environmental Sciences, Kyoto, Japan.
Yuji
Y
Iwata
Interdepartmental Doctoral Program in Anthropological Sciences, Stony Brook University, Stony Brook, New York, United States of America.
Jessica L
JL
Lodwick
Muséum National d¹Histoire Naturelle, Musée de l'Homme, National Center for Scientific Research (CNRS), University Paris Diderot (Paris 7) Éco-anthropologie et Ethnobiologie, Paris, France.
Shelly
S
Masi
Department of Anthropology, University of Georgia, Athens, GA, United States of America.
Roberta
R
Salmi
Dian Fossey Gorilla Fund International, Atlanta, GA, United States of America.
Tara S
TS
Stoinski
World Wildlife Fund-CAR, Bangui, Central African Republic.
Angelique
A
Todd
Dian Fossey Gorilla Fund International, Atlanta, GA, United States of America.
Veronica
V
Vercellio
Kyoto University, Graduate School of Sciences, Kyoto, Japan.
Juichi
J
Yamagiwa
D000349:Africa; D000818:Animals; D003469:Culture; D004463:Ecology; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D006071:Gorilla gorilla / Q000235:genetics / Q000502:physiology*; D007398:Interpersonal Relations; D002679:Pan troglodytes; D010641:Phenotype; D057079:Pongo; D011148:Pongo pygmaeus; D012919:Social Behavior