Monkeys would take banana pieces out of my son's hand so quickly that it was hard to get a photograph of the moment of contact. I told my son that getting a photo of the point where the hand of man and the hand of monkey were reaching out and making contact was a bit like the central scene in the middle of the ceiling of the Sistine Chapel.
My son was standing on the bow of a boat on a wildlife excursion on the Tempisque River in Palo Verde National Park. It is a wetlands area that flows into the Gulf of Nicoya just east of the Tamarindo area. The boats will pull up to a particular part of the woods where the monkeys have trained humans to stop and, if you are so inclined, you can feed the monkeys.
Tomorrow I will show a photo of what happened right after the above exchange of a banana piece.