One photographer has proven that eyes really are the window to the soul in these critically endangered great apes.
Mark Edward Harris' photo series 'Orangutans On a Thin Vine' shines a light on a species whose future is particularly uncertain as habitats of these majestic primates are disappearing rapidly.
As a talented (human) portrait photographer, Harris was inspired to create this series after learning that the striking similarities between orangutans and humans date back centuries.
While modern science has shown that human and orangutan genomes are 97 per cent identical, long before that the Malay people noticed the similarities and gave the name orangutan, which comes from the Malay words 'orang' (people) and 'hutan' (forest).
Harris' photo series made the curatorial selection for The Prix de la Photographie Paris' (Px3) 'State of the World' photo contest.
The aim of the contest is to share important global stories, in order to focus our eyes and minds on issues that are current and crucial in our world.
Orangutan populations have declined significantly over the past hundred years due to habitat loss and destruction in their native countries Sumatra and Borneo, where forests are giving way to palm oil plantations.
All three species of orangutan are critically endangered according to the IUCN (International Union for Conservation of Nature).
Frighteningly, the population on the island of Borneo has seen local extinctions as orangutan habitats are reduced to an area within the Sabangau National Park.
'Orangutans On a Thin Vine' will be open to the public when the series is exhibited with other winning works at the Px3 Paris Photo Prize exhibition.
This runs from October 25 to October 31 at Espace Beaurepaire in the French capital.