Spectral analysis of the distributions oscillations for 20 colonies of one apiary.

All 20 colonies from one apiary are shown, including those used in Fig 2. The spectra have been normalised to their maximum and subsequently sorted to show the colonies with the shortest period (top) to the longest (bottom). Note many spectral maxima in remarkable agreement, between 21 and 26 days. Colony 2, which was found 'drone laying' for a month or so, exhibits small peaks that are additional to the single one seen for Colony 5 and 6. Only one colony (No. 4) out of 20 does not exhibit a clear peak in the range 21 to 26 days. Only four colonies out of 20 do not have their maximum in that same range. Two of these (No. 12, and No. 14) are colonies that failed a month after their primary swarm took place.