Orangutans are remarkably similar to humans in terms of anatomy and physiology. Like humans, they have opposable thumbs, lack of external tails, similar internal organ arrangements, DNA pair similarities, and so forth.
However, humans are also defined by social, religious, cultural, behavioral, spiritual, mental, and psychological aspects, and here the differences between humans and orangutans are striking. For example, unlike orangutans, people have complex forms of verbal communication and use symbols in communication. Although orangutans do show some evidence of socially learned traditions that are passed down through the generations (including using leaves as napkins to wipe food from their chins), humans have complex social organizations and technologies, refined systems of governance, and practice and transmit religious traditions. Many religions consider another qualitative difference to be that the human body encompasses not only a physical component, but also an immaterial or spiritual aspect (or soul).