Comparison of Tritonia diomedea orientations to odour plumes, with and without rhinophores
| Rhinophores . | Odour . | N . | θ (deg.) . | r . | F2,N-2 . | P . | 95% CL (deg.) . |
|---|---|---|---|---|---|---|---|
| Present | Prey | 8 | 003 | 0.58 | 8.83 | 0.016 | 063, 304 |
| Predator | 8 | 171 | 0.70 | 5.03 | 0.052 | ns | |
| Predator* | 7 | 171 | 0.90 | 420 | <0.0001 | 142, 202 | |
| Control | 8 | 119 | 0.30 | 1.08 | 0.40 | ns | |
| Absent | Prey | 7 | 076 | 0.23 | 0.48 | 0.64 | ns |
| Predator | 7 | 177 | 0.14 | 0.16 | 0.85 | ns | |
| Control | 7 | 042 | 0.26 | 0.38 | 0.70 | ns |
| Rhinophores . | Odour . | N . | θ (deg.) . | r . | F2,N-2 . | P . | 95% CL (deg.) . |
|---|---|---|---|---|---|---|---|
| Present | Prey | 8 | 003 | 0.58 | 8.83 | 0.016 | 063, 304 |
| Predator | 8 | 171 | 0.70 | 5.03 | 0.052 | ns | |
| Predator* | 7 | 171 | 0.90 | 420 | <0.0001 | 142, 202 | |
| Control | 8 | 119 | 0.30 | 1.08 | 0.40 | ns | |
| Absent | Prey | 7 | 076 | 0.23 | 0.48 | 0.64 | ns |
| Predator | 7 | 177 | 0.14 | 0.16 | 0.85 | ns | |
| Control | 7 | 042 | 0.26 | 0.38 | 0.70 | ns |
Hotelling tests of 2nd order mean headings relative to flow (θ, r; 0°=upstream) were used to assess the significance of mean slug orientations over the 2 min interval, 30 s after encountering a prey, predator or control odour plume in the flow tank. CL, 95% confidence limits for sample means significant at P=0.05; ns, not significant.
Two sets of values are presented for orientation relative to predator odour, the first is the complete dataset, the second (*) does not include a single exceptional animal (see text). ns, not significant.