Table 2.
Attempts and success of small (2 birds) and large (6 birds) house sparrow groups during the first 30 min of the problem-solving test
| Dependent variable | Small groups | Large groups | F1,13 | P |
|---|---|---|---|---|
| Total no. of wells opened in the group | 0.29 ± 0.18 | 2.71 ± 0.42 | 27.97 | <0.001 |
| No. of birds trying to open the wells | 1.86 ± 0.14 | 5.00 ± 0.38 | 60.50 | <0.001 |
| Proportion of birds trying to open the wells | 0.93 ± 0.07 | 0.92 ± 0.04 | 0.02 | 0.879 |
| Total no. of attempts to problem solve | 10.57 ± 3.57 | 38.86 ± 8.7 | 9.05 | 0.011 |
| Total no. of attempts to problem solve before the first opening | 9.86 ± 3.36 | 15.86 ± 5.66 | 0.83 | 0.380 |
| Per-capita no. of attempts | 5.29 ± 1.79 | 7.05 ± 1.59 | 0.57 | 0.466 |
| Per-capita no. of attempts before the first opening | 4.93 ± 1.68 | 2.81 ± 1.07 | 1.13 | 0.309 |
| No. of birds opening the wells | 0.29 ± 0.18 | 2.29 ± 0.18 | 58.8 | <0.001 |
| Proportion of birds opening the wells | 0.14 ± 0.09 | 0.43 ± 0.04 | 7.96 | 0.015 |
| Proportion of tryers succeeding to open | 0.14 ± 0.09 | 0.48 ± 0.05 | 9.70 | 0.009 |
| Per-capita no. of wells opened | 0.14 ± 0.09 | 0.51 ± 0.09 | 8.33 | 0.014 |
| Group's total time spent on feeder, s | 279.6 ± 77.1 | 1003.4 ± 138.3 | 20.92 | 0.001 |
| Group's feeder bout length, s | 31.7 ± 7.6 | 142.4 ± 37.8 | 8.29 | 0.014 |
| Individual's total time spent on feeder, s | 168.1 ± 54.4 | 431.6 ± 63.0 | 9.86 | 0.009 |
| Individual's feeder bout length, s | 23.4 ± 5.5 | 59.7 ± 5.9 | 13.91 | 0.003 |
| Individual's feeder bout length before the first opening, s | 22.3 ± 4.9 | 11.3 ± 2.4 | 4.79 | 0.049 |
| Group's latency to first visit the feeder, s | 98 (48–1,490) | 93 (0–366) | 26.5 | 0.848 |
| Individual's latency to first visit the feeder, s | 131 (48–1,658) | 116 (0–869) | 21.0 | 0.710 |
| Individual's scanning rate, no. of scans/s | 0.33 ± 0.03 | 0.28 ± 0.02 | 2.86 | 0.117 |
| Individual's scanning rate before the first opening | 0.32 ± 0.02 | 0.30 ± 0.02 | 0.21 | 0.652 |
Data are reported from the analyses of video recordings of 7 small and 7 large groups. Statistics are shown for the effect of group size in the final models. For latencies to visit the feeder, median (minimum–maximum) values and results of Mann–Whitney tests are given because normality and homoscedasticity were not held in these cases.