Figure 2. Results of intra-specific and inter-specific two-female experiments.

The experiments show that the pheromones are species-specific and extremely potent. The focal species in the experiment is indicated on top. The mean cumulative duration of the behaviour in seconds (+/− S.E.) is indicated on the y-axis. Abbreviation for stimuli (indicated on x-axis): Ia, alpine newt male courtship water; Lh, palmate newt male courtship water; W, control water.