Science Literature

Crop circles are patterns formed by the flattening of crops. They have been reported for hundreds of years and are reputed to appear around the world at a rate of one every evening. They only form during the night. Crop circles have always had something extraordinary about them, stimulating "mowing devil" explanations and also the influence of aliens. What are we to make of these phenomena? This is a good opportunity to discuss how a scientific mind approaches the problems and the relevance of design inferences to science. In a recent feature article on crop circles, Richard Taylor writes:

"Speculation over the origin of crop circles has raged since they were first reported in England in the 1600s, with rolling hedgehogs, urinating cattle, romping romantic couples and the actions of a "mowing devil" all offered as early explanations. In 1678 a series of circles in Hertfordshire was attributed to the devil because the manufacture appeared to be beyond human capabilities. According to a report in a 1678 issue of News Out of Hartfordshire, the devil "placed every straw with an exactness that would have taken up above an age for any man to perform what he [the devil] did that one night"."

A field of fractals. On 29 July 1996 this crop circle appeared on Windmill Hill near Avebury, UK. Its design is based on an equation formulated by Gaston Julia in 1918. A similar "Triple Julia" fractal design was also used in a crop circle in Switzerland last year. (Courtesy: Steve Alexander. Source here)

Apparently, the first scientific analysis of crop circles invoked "Law" as an explanation. This was in 1686, by a British scientist called Robert Plot. Linear wind surges and circular eddies were considered to account for the observations. Natural phenomena continue to be considered. More recently, a prominent advocate has been Terence Meaden, a Canadian meteorologist and physicist.

"In 1980 Meaden [. . .] propos[ed] that the curvature of hillsides in southern England affected the local airflow, allowing whirlwinds to stabilize their positions long enough to define circles in the crop fields."

Even Professor Stephen Hawking has given some credence to weather-related causation:

"When a spate of circles appeared in the countryside near his Cambridge home in 1991, Hawking told a local newspaper that "crop circles are either hoaxes or formed by vortex movement of air"."

"Chance" has not been favoured as an explanation of the data. Rolling hedgehogs and urinating cattle leave their marks, but nothing like crop circles! Analysts have been impressed by the specified complexity of the flattened crops. The choice for them has always been either "Law" or "Design".

Whilst many suspected human activity, people did not own-up to making crop circles. If this is the explanation, the perpetrators have kept remarkably silent about their accomplishments! There were two schools of thought: one group concentrated on humans, whereas the other group looked for aliens and UFOs.

"In the waning decades of the 20th century, this conclusion ignited a heated aliens-versus-humans debate, with "UFOlogists" looking to outer space for the circles' artistic creators, while "cereologists" concentrated on hunting for terrestrial hoaxers. This debate was complicated by the fact that the creators (whoever they were) were clearly science-savvy. In particular, one formation that appeared next to Chilbolton Observatory in Hampshire appeared to be a reply to a "search for extraterrestrial intelligence" signal beamed into space 30 years earlier."

However, this discourse changed in 1991, when "two unassuming men in their sixties declared that they had been creating crop circles for more than 25 years." At last, the silence had been broken! These two could not be responsible for all the crop circles made in this period, but they did confess to making 250 of them (20% of the total in England).

"Their hobby had begun one summer evening in the mid-1970s, when artist Douglas Bower recounted a story to his friend David Chorley about an Australian farmer who had reported a UFO rising into the sky and leaving behind a circular "saucer nest". As Bower and Chorley strolled home from the pub through the English countryside, they created their first imitation nest."

According to Taylor, the Bower & Chorley announcement triggered a revival in construction of crop circles. The practice went international, and was characterised by sophistication. Although England still boasts 50% of each year's crop circles, they occur in Europe, North and South America, Russia, Australia, Japan and India.

"Artists who readily admit to having made crop circles in the past say they do not know who is responsible for all of today's masterworks. This is partly because many crop-circle artists have followed the conventions established by their predecessors: creating their pictographs anonymously, under cover of darkness, and leaving the scene free of human traces. But although the new artists are traditionalists in this sense, in other respects their craft has moved on considerably. Today's artists, for example, have access to computers, GPS equipment and lasers to help map out their patterns."

The rise of high technology crop circle creation has been noted in the media, and an example is an article by Nick Collins in the Daily Telegraph. What some regard as unexpected mathematical sophistication in human hoaxers, others continue to regard as the signatures of alien minds.

"Today's crop-circle designs are more complex than ever, featuring up to 2000 individual shapes arranged using intricate construction lines that are invisible to the casual observer. The increase in available computing power has also meant that iterative equations are now frequently used to generate fractal shapes such as the Triple Julia design, which reappeared in Switzerland last year. Other famous fractal icons such as the Mandelbrot set, the Julia set and the Koch snowflake have also popped up regularly in crop fields since 1991."

There are still mysteries about how these patterns are made, how secrecy is maintained, and how so much is done in the available time. These puzzles continue to engage the interest of enthusiasts. Taylor writes: "Crop-circle artists are not going to give up their secrets easily." Interest in the alien explanation continues. Are we dealing here with "The most science-oriented art movement in history"? - as Taylor suggests. Or are we witnessing tangible signs of the presence of aliens? As has been pointed out many times before, design inferences allow us to infer intelligent causation, but the identity of an intelligent agent is a separate issue which may or may not be easy to resolve. As this summer period is a time for rest and relaxation for many of us, we have an opportunity to reflect further on these questions - and hopefully reach some answers.

Coming soon to a field near you
Richard Taylor
Physics World, August 2011, 26-31. (pdf here)

Serious studies of crop circles have long been hampered by conspiracy theories and the secretive nature of circle-makers - plus scientists' reluctance to engage with a "fringe" topic. But, as Richard Taylor argues, discovering how circle artists create their most complex patterns could have implications for biophysics