National Geographic: Do Chimps Grieve?

"Cameroon—At the Sanaga-Yong Chimpanzee Rescue Center, more than a dozen residents form a gallery of grief, looking on as Dorothy—a beloved female felled in her late 40s by heart failure—is borne to her burial." - National Geographic

This photo took my breath away, and at least for me the evidence is absolute that there are animals capable of feeling complex emotions as we do. The grieving on the faces of the Chimps, is for me, undeniable. What do other people think?

The photo appears in the November issue of National Geographic in their Visions of Earth 2009 article.