Figure 3.

Responses (mean±s.e.) of female X. birchmanni to chemical conspecific (black bars) and heterospecific X. malinche (white bars) male cues. ‘Humic acid’ represents experimental fish that were subjected to a preference trial conducted in 200 mg l⁻¹ HA; hatched-shaded area depicts the one trial conducted in HA. ‘Control’ indicates fish that were consistently tested in water not containing supplemental HA. Bars surrounded by a black box indicate a significant difference (p<0.001) in females' response to conspecific male cues relative to other trials (bars not included in boxed area). Asterisks indicate a significant preference for conspecific cues over heterospecific: *p<0.05; **p<0.01, ***p<0.001. (a) Latency to respond to conspecific and heterospecific odour cues. (b) Females' association time with each cue. (c) The frequency that females were within one body length of conspecific and heterospecific stimuli outflow.