 The weather theory suffered a serious blow in 1991, but Hawking's point about hoaxes was supported when Bower and Chorley stated that they had been responsible for making all those circles.By the end of 1991 Meaden conceded that those circles that had complex designs were made by hoaxers.Since becoming the focus of widespread media attention in the 1980s, crop circles have become the subject of speculation by various paranormal, ufological, and anomalistic investigators ranging from proposals that they were created by bizarre meteorological phenomena to messages from extraterrestrial beings.