#throwbackthursday October 21, 2005 When a colored square appears on the screen, chimpanzee Ai chooses the matching kanji character correctly, and vice versa.

#throwbackthursday October 25, 2005 When given paintbrushes and paint, the PRI chimpanzees paint pictures, even though we don't give them any food rewards for doing so. It seems that, just like humans, they enjoy painting for the sheer pleasure of it. Here is Ai, then aged 29 (est.), painting a picture. Ai really is quite the artist; such wonderfully bold brushstrokes!

#throwbackthursday October 27, 2005 Autumn also seems to be the season for art among the PRI chimps, doesn't it!? Pal, then aged five, creates a masterpiece with her liberal brushwork, the edge of the paper imposing no restrictions.