Photo from National Geographic NewsA research done late last year by Masataka et al. (2009) was published on PLoS ONE titled "Free-Ranging Macaque Mothers Exaggerate Tool-Using Behavior when Observed by Offspring". The research found that long-tailed macaque mothers emphasized tool-using action and performed such action longer in the presence of their infant. A group of long-tailed macaques (Macaca fascicularis) in Thailand were recorded using human hair as dental floss to clean their teeth. Mothers would emphasize and repeat the techniques on how to use human hair (tool) in front of the infant in longer periods between each bout. Masataka et al. interpret that such behavior is evidence that mother macaques are exaggerating their action in tool-use to facilitate learning in their infants. Read the National Geographic article here.
This study is important when we look at "culture" and how we define it. Understandably, "culture" is a hard-to-define term and non-human culture are predominantly defined as a knowledge that can be passed down from one generation to another. Observation on culture transfer between mother long-tailed macaques to their infants proves not only that "culture" exist in non-human primates but it is observable.