Flies choose to irritate

SCIENTISTS claim to have found evidence of free will in fruit flies.

If confirmed, the discovery could overturn basic assumptions about differences between humans and animals: the blowie or wasp that will not leave you alone is not innocently reacting to a biological program, it is choosing to be a pest.

Insects are generally regarded as biological machines that only respond to external stimuli.

Apparently variable behaviour in such animals is usually attributed to random brain activity.

An international study of fruit flies has now shown that such variability cannot simply be random - it appears to be generated spontaneously, but not randomly.

The tested flies looked as if they exercised free will.

"We found that there must be an evolved function in the fly brain, which leads to spontaneous variations in fly behaviour,'' said George Sugihara, one of the researchers from the Scripps Institution of Oceanography at the University of California, San Diego.

"The results indicate a mechanism which might be common to many other animals and could form the biological foundation for what we experience as free will.''

The research is reported in the online journal PLoS ONE.