Hi Allen Please, please, please ... ... would you mind reading one short, clear paper? It should take about 10 min at the most, and if you are a fast reader 5 min should be enough. No jargon, clear diagrams. http://www.neurobiologie.fu-berlin.de/menzel/Pub_AGmenzel/Riley,Greggers,Smith,Reynolds,Menzel_Nature_2005.pdf Your opinion matters to me! all the best Gavin. -- Visit www.honeybeeworld.com/bee-l for rules, FAQ and other info ---