In conclusion, the habits of the common cuckoo provide us with another one of natures mysteries. When human children are raised by foster parents they generally take on the habits and vocal traits of the rearing parents. Whereas the same species of cuckoo, which can cover a vast territory, having been raised by different hosts, all have the same distinct call. The same familiar call we hear when the engraved faced clock strikes the hour, and the little wooden doors swing open. Somehow I just can't picture the sound of a sparrow tweeting at the top of the hour.