And you thought your mother was cold.
Mothers really don't get more emotionally remote than inanimate objects. But for some orphaned animals, inanimate objects are better than human interaction alone. In these cases, they help socialize the baby animals so they will grow used to others of their kind.
At the Brookfield Zoo in Brookfield, Illinois, three Humbolt Penguins hatched, but were not receiving proper care from their parents. Keepers decided to hand-rear the babies, and placed two large stuffed penguins in their brooding room to play the role of parents. These plush toys helped reinforce the chicks' identities as birds and not humans, and distracted them from the presence of human hands during feedings. Additionally, the large stuffed toys gave the penguins something warm to snuggle up with. At feeding time, the chicks instinctively learned to solicit food from their stuffed parents, pecking at them as they would in the wild. Eventually the birds were socialized and rejoined the zoo's penguin colony.
The Brookfield Zoo has also rescued baby callimico monkeys. During their first few days of life, malnourished infant callimicos are placed inside incubators with stuffed toys. The toy becomes the baby monkey's surrogate parent. The infant bonds with the toy and later other monkeys—but not the human caretakers.
At the New Forest Otter, Owl and Wildlife Park in Hampshire, England, a flock of orphaned baby tawny owls have also snuggled up with a stuffed owl. According to the Daily Mail, they burrow under the toy's wings to stay warm. These birds probably wandered off from their mothers or were forced out of the nest.
Also at New Forest, four orphaned baby hedgehogs became attached to a bristly cleaning brush because they thought it was their mother. Since the brush was used to sweep a yard, it smelled like their natural habitat, and the texture of its bristles reminded them of a mother hedgehog.