Geoff, i haven't read the following, which apparently support the photoperiodism hypothesis. CHEREDNIKOV, A. V. (1966) [Preparation of bees for wintering and significance of fat- body for their activity.] Bdzhil'nitstvo 2: 18-23 In Ukrainian 721/68 CHEREDNIKOV, A. V.(1967) [Photoperiodism in honeybees Apis mellifera L. (Hymenoptera, Apidae)]. Ent. Obozr: 46(1): 60-67 In Russian -- Randy Oliver Grass Valley, CA www.ScientificBeekeeping.com *********************************************** The BEE-L mailing list is powered by L-Soft's renowned LISTSERV(R) list management software. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html