Humans are evolved orangutans! Humans have more features uniquely shared with orangutans than with any other living ape. Schwartz (1984) proposed that humans are more closely related to orangutans than to chimpanzees - a model that contradicts the greater molecular similarity (often misrepresented as being the sole 'genetic' component of evolution) of base pair sequences in humans and chimpanzees.
The orangutan model presents a conundrum for biological systematics over how to chose between morphological and genetic evidence when they are in conflict. Base pair sequences simiarlity may not always accurately predict phylogenetic relationship and morphology may represent an independently reliable source of information on evolutionary relationships.
This web page provides links to information bearing on the question of why orangutans are more likely to represent our closest living relative than the chimpanzee or gorilla.