Marty’s photo of the day #4639: Being that this is photo 4,639, when I go through my photo files each morning to decide what to post, sometimes it’s frustrating finding something of high quality that I haven’t posted before. That’s especially the case when I go through the photos I took while working on my first book, Cool Creatures, Hot Planet: Exploring the Seven Continents. Today is one of those “How did I miss this one all these years?” photos: an orangutan I photographed on the island of Borneo.