<P> Sexual attraction to humans can develop in non-human mammals or birds as a result of sexual imprinting when reared from young by humans . One example is London Zoo female giant panda Chi Chi . When taken to Moscow Zoo for mating with the male giant panda An An, she refused his attempts to mate with her, but made a full sexual self - presentation to a zookeeper . </P> <P> It commonly occurs in falconry birds reared from hatching by humans . Such birds are called "imprints" in falconry . When an imprint must be bred from, the breeder lets the male bird copulate with their head while they are wearing a special hat with pockets on to catch the male bird's semen . The breeder then courts a suitable imprint female bird (including offering food, if it is part of that species's normal courtship). At "copulation," the breeder puts the flat of one hand on the female bird's back to represent the weight of a male bird, and with the other hand uses a pipette, or a hypodermic syringe without a needle, to squirt the semen into the female's cloaca . </P> <P> Sexual imprinting on inanimate objects is a popular theory concerning the development of sexual fetishism . For example, according to this theory, imprinting on shoes or boots (as with Konrad Lorenz's geese) would be the cause of shoe fetishism . </P> <P> Reverse sexual imprinting is also seen in instances where two people who live in domestic proximity during the first few years in the life of either one become desensitized to later close sexual attraction . This phenomenon, known as the Westermarck effect, was first formally described by Finnish anthropologist Edvard Westermarck in his book The History of Human Marriage (1891). The Westermarck effect has since been observed in many places and cultures, including in the Israeli kibbutz system, and the Chinese shim - pua marriage customs, as well as in biological - related families . </P>

What is it called when ducklings follow their mother