A very quick reply to recent comments... Orangutans clearly recognise each other (Princess will always run from Siswi) but because they are generally semi-solitary and uncommunicative you rarely get the insight into whether there is recognition of a biological relationship.
Regarding the drinking of milk, orangutans naturally have a high-fibre, low protein diet with huge fluctuations in sugar intake, depending on the availability of fruit in the forest. It seems fair enough that orphaned, infant orangutans are bottle fed with milk made for human babies. Milk has always been given as supplimentary to the orangutan's fruit and it has become part of the rehabilitant's diet.
Abraham - orphaned infant
Tom - dominant male
Brigitta, good to know you still think of Siswi! Regarding post, the best thing to do is send anything to the London Office. I look forward to seeing the photos.
Orangutan Foundation 7 Kent Terrace London NW1 4RP