Chongo has confided in me that male chimps may experience sexual arousal when perusing photos of a great many things. Some examples are: female chimps, female apes of several other closely related species, female humans (MAJOR spike on the graph!), lipstick applicators, feminine apparel, Victoria's Secret catalogs, fresh fruit, a nice scenic view, tall buildings, fast cars, pinstripe suits, a baseball stadium, a bottle of whiskey, a Cuban cigar, and a well-oiled gun...

He says that his favorite Beatles song is "Happiness Is A Warm Gun".