In conclusion, the results of this preliminary study clearly indicate that bouts of incubation begin during egg laying in the House Sparrow, usually with the laying of the first egg. These findings are consistent with the hypothesis that tactile feedback from the eggs (through the brood patch) may play a role in the mechanism controlling clutch size in the species. They also suggest that egg removal in experiments to test for determinate or indeterminate laying in a species should occur soon after egg laying to obviate the possible effects of tactile feedback from the egg on the termination of laying.