Happy International Primate Day, celebrated on September 1st annually.
Though now recognized as a Mandrill (Mandrillus sphinx), this work is also still known as Gorilla, based on an earlier misidentification. Apparently even Munch himself wasn’t sure what kind of primate it was, calling it an orangutan in notes found on another copy.
Just for the record, here is the primate tree shakes out:
(gorillas and orangutans are both in the “Great Apes” tier; the mandrill is part of the “Old World Monkeys” branch)