Figure 4: Effect of crossed airflow.

(a) In four moles, short, open polyethylene tubes were inserted into the nostrils to alter the airflow direction. Moles were tested in both uncrossed (left) and crossed (right) condition. (b,c) Examples of nose tracks for the uncrossed and crossed condition. For the two moles tested with the radial array, each animal quickly found the food (green traces) in five out of five trials for the uncrossed condition. In the crossed condition, the moles did not find the food in any of the five trials each, but often searched to the left and right of the food item (red traces) or completely avoided the food item. (d) In the 144-well array, moles in the uncrossed condition spent a significantly greater amount of time with the tubes over the food item as measured for a 1-cm square around the food well (dotted square). (e). Results for animal no. 11 (left) and 12 (right) in the 144-well array showing the amount of time over the square in d (two-tailed t-test, animal no. 11, nine trials for each condition, P=0.014; animal no. 12, 10 trials for each condition, P=0.005). Each trial was initiated when the animal came within 3 cm of the food item and continued for 10 s thereafter. The tracks and analyses used the position of the midpoint between the tube openings. Scale bars, 1 cm (a) and 4 cm (b–d).