Table 3.
Results of behavioural experiments using the olfactometer on larvae of Zenopontonia soror.
| Aquarium A VS aquarium B | Results | Statistics | ||||
|---|---|---|---|---|---|---|
| Trials | Null | A | B | Motion behaviour | Orientation behaviour | |
| Negative control | ||||||
| Seawater (A) VS seawater (B) | 20 | 12 | 4 | 4 | – | 1 |
| Water conditioned by the initial host | ||||||
| Culcita novaeguineae (A) VS seawater (B) | 40 | 4 | 33 | 3 | 1.3 × 10–4 | 2.3 × 10–7 |
| Water conditioned by asterosaponins extracted from potential host asteroids | ||||||
| C. novaeguineae extract (A) VS seawater (B) | 40 | 5 | 33 | 2 | 3.9 × 10–4 | 3.7 × 10–8 |
| Acanthaster planci extract (A) VS seawater (B) | 40 | 6 | 32 | 2 | 1 × 10–3 | 6.4 × 10–8 |
| Comparison of two waters conditioned by asteroids saponins extracts | ||||||
| C. novaeguineae extract (A) VS A. planci extract (B) | 40 | 8 | 29 | 3 | 4.5 × 10–3 | 2.6 × 10–5 |
Five different tests were performed on a minimum of 20 different larvae. Three individuals of Culcita novaeguineae were used to prepare conditioned water and, for each saponins extract, at least 3 individuals for each species were used. Results show the number of trials, spread out among the shrimps that did not converge significatively toward the device (Null), those that orientated adequately toward the cues from aquarium A (A) and those that orientated toward the cues coming from the aquarium B (B). The P value of the chi2 test and the binomial test are respectively found in motion and orientation behaviour columns. Significant results (P value, 0.01) are underlined and in bold.