Despite its initial survival value, however, imprinting on something other than your kind can become problematic when you reach sexual maturity. Though it operates by different mechanisms, sexual imprinting—the process by which an animal learns to recognize an appropriate mate—is also strongly linked to early parental experience.
In 1976 there were about 100 whooping cranes (Grus americana), the tallest North American bird, left in the world. Conservationists tried to forestall their extinction by breeding cranes in captivity and reintroducing them into the wild, relying on one adult female to continue her rare genetic lineage. Hatched and hand-reared in the San Antonio Zoo, "Tex" wanted nothing to do with the handsome male whoopers she later met; she performed her elaborate mating dance solely for her human keepers. Only after George Archibald, one of the world's leading crane experts, literally moved in with Tex for several months, formed a pair-bond with her, and joined her repeatedly in the species-specific courting ritual, did she lay the first egg of her life at age 10.
Such sexual confusion also shows up in sheep and goats, which are, along with most ungulates, precocial species. When Keith Kendrick of the Babraham Institute in Cambridge, England, and his colleagues cross-fostered newborn kids and lambs with mothers from the other species, the infants formed strong bonds with their foster moms. The goats grew up thinking they were sheep, and vice versa.
And even though mammals are thought to exhibit more behavioral flexibility than geese, when two same-species siblings were raised together by a mother of the other species, the offspring's sexual preference in adulthood was for their foster mother's species. Further, males that had been cross-fostered preferred to mate with females of their moms' species even after living exclusively with their genetic species for three years.
Nevertheless, it remains unclear whether all parents (or foster parents) become "imprinted" on their infants' brains in a manner similar to that seen in precocial birds. In the meantime, try to avoid newly hatched chicks—unless you're ready to take on the responsibilities of motherhood.