From the Cincinnati Zoo’s wonderful Instagram feed:
Bonobo smiles can mean different things like fear or playfulness. They also have large grins when they are wrestling with other bonobos and laughing. Bonobos are a critically endangered species in the wild. They inhabit only one region in the Democratic Republic of Congo (DRC), there are only an estimated 5,000 to 10,000 left in the wild. The species face constant threat from loss of habitat due to deforestation and mineral mining including diamonds and coltan – an ore used in cellphones and computers.