It is implied in the passage that………… .

There is an ancient belief that when a female wolf loses a young cub, she seeks a human child to take its place. Romulus and Remus, the legendary twin founders of Rome, were supposed to have been cared for by wolves. The idea actually became believable in the late 19th century when a French doctor found a naked ten-year-old boy wandering in the woods. He did not walk upright, could not speak intelligently, nor relate to people: he only growled like a wolf and stared at them. Finally the doctor won the boy's confidence and began to work with him. After many long years of devoted and patient instruction, the doctor was able to get the boy to clothe and feed himself, recognise and say a number of words, and even to write a little.