Camp Leakey, an open-to-visitors research facility in central Borneo, is home to a special group of orangutans who have been rescued from captivity and returned to the wild. In this heart-warming archive clip from the 2002 BBC documentary series The Life of Mammals, David Attenborough observes how close orangutan behaviour is to our own. Since they have lived partly in our world as well as theirs, the Camp Leakey orangutans offer particularly good insight into what we all have in common.

Tanjung Puting National Park, where Camp Leakey is located, is just one of five Indonesian jungles where travellers can get a glimpse of orangutans in the wild.

All week, BBC Travel is running archive BBC Earth clips to celebrate more than 50 years of natural history film making by Sir David Attenborough! For more natural history exclusives, check out the BBC Earth YouTube channel or follow BBC Earth on Facebook or Twitter.