What is “a behaviour”?

A fascinating article in the on-line New York Times today ... http://www.nytimes.com/2009/07/21/science/21angier.html?_r=1 This is probably hard-core geek thought for biologists, but a behavioural scientist has been trying to define "what is a behaviour" on the grounds that if you can't define it you can't study it.  Despite journals and departments galore studying this field he [...]