博士後期課程（学振DC2）の花塚君がベトナム（ハノイ）で開催された、国際霊長類学会大会（International Primatological Society Congresses, 11-16 August, 2014）で以下の発表をしました。
THE EFFECT OF ANIMAL KEEPERS ON THE DRAWING BEHAVIOR OF A BORNEAN ORANGUTAN (PONGO PYGMAEUS)
Y. HANAZUKA1,2, M. Tanaka3 and A. Midorikawa1
1Chuo University, Hachioji, Tokyo, Japan, 2Japan Society for the promotion of Science, 3Wildlife Research Center, Kyoto University, Kyoto, Japan
Human infants often engage in drawing, which may be aided by caregivers. However, whether such guidance and support is required for orangutans to draw remains unclear. This study investigated the factors that influence the drawing behavior of orangutans. The participant was an approximately 55-year-old female Bornean orangutan (Pongo pygmaeus) in the Tama Zoological Park in Tokyo, Japan, named Molly. Her drawings from between April 2007 and March 2008 were scanned into a computer, and 18 of the 233 drawings were pseudo-randomly selected as target stimuli. The stimuli were rated by 61 college students based on the semantic differential (SD) method, and the results were subjected to factor analysis. Two factors were identified, “favorite” and “activity”, and we investigated the relationships between these two factors and three variables: the characteristics of the animal keeper (gender, age, and time spent with Molly), outside temperature, and location before drawing (outdoors or indoors). Multiple regression analysis revealed that the characteristics of the keeper were a strong predictor of the favorite drawing. Other candidate predictor variables were not significantly related to ratings. These results suggest that the drawing behavior of orangutans may be influenced by the presence of an animal keeper.