CROWDING AND ACTIVITY

Abstract
When the relative velocity of flies is estimated from the frequency of contact of flies with a given area, the resulting picture of activity is misleading because of time-wasting activities arising from encounters between flies. Prediction of this encounter rate is greatly facilitated by the use of Lloyds (1967) index of crowding, which allows for the effects of the non-random distribution of the flies. Prediction of the number of contacts of flies with an inscribed area within the experimental container, was highly successful when the effects of the non-random locomotion of the flies was included in the model of activity.