Table 1.
Relative helmet length (HL) and relative tail spine length (TL; %; mean (±s.e.)) and absolute body length (BL; μm; mean (±s.e.)) of D. lumholtzi and D. pulicaria raised with (kairomone and predation) and without (control) chemical cues exuded by fishes. Adults of both Daphnia species were recorded at an early (1) and a late (2) sampling date of the experiment with (fish kairomone and predation) and without (control; competition) fish predation. n indicates the number of individual Daphnia pooled from 8 to 10 replicates per treatment. Each species was analysed for treatment effects using a nested ANOVA with 8–10 replicates per treatment as a random factor.
| D. lumholtzi | D. pulicaria | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| control (without fishes) | fish kairomone/predation | control (without fishes) | fish kairomone/predation | ||||||||
| trait | date | mean (±s.e.) | n | mean (±s.e.) | n | p-value | mean (±s.e.) | n | mean (±s.e.) | n | p-value |
| HL(%) | 1 | 10.80 (0.24) | 105 | 33.58 (1.01) | 93 | <0.001 | 3.70 (0.07) | 152 | 3.58 (0.05) | 214 | 0.173 |
| 2 | 10.19 (0.16) | 159 | 32.84 (0.58) | 197 | <0.001 | 4.77 (0.10) | 211 | 3.87 (0.13) | 57 | 0.008 | |
| TL(%) | 1 | 65.72 (1.11) | 105 | 91.22 (1.77) | 93 | <0.001 | 30.67 (0.34) | 152 | 37.26 (0.32) | 214 | <0.001 |
| 2 | 48.80 (0.76) | 159 | 90.35 (1.04) | 197 | <0.001 | 24.53 (0.29) | 211 | 35.55 (0.73) | 57 | <0.001 | |
| BL(μm) | 1 | 1520.57 (14.29) | 105 | 1530.53 (28.63) | 93 | 0.611 | 1879.80 (17.33) | 152 | 1589.73 (12.14) | 214 | <0.001 |
| 2 | 1578.49 (12.09) | 159 | 1448.64 (13.31) | 197 | <0.001 | 1865.89 (13.86) | 211 | 1478.62 (13.74) | 57 | <0.001 | |