Agonistic display during dyadic encounters between animals of the same sex.

<p>(A) Frequency of evasive behaviour (mean ± SE) depended on the sex and previous experience with the artificial odorant. Naïve males performed this kind of behaviours significantly more. (B) Aggressive behaviours (mean ± SE) were more frequent in males than in females. <i>H</i> and <i>p</i>-values from Scheirer-Ray-Hare test are shown in each figure.</p

Exploration time (mean ± SE) during dyadic interactions between individuals of the same sex.

<p>Males (in grey) explored significantly more the anogenital and anterior area of their partners (a non-familiarized conspecific impregnated with <i>eucalyptol</i>) than females (in black). Asterisks represent significant differences between males and females, Scheirer-Ray-Hare test (*<i>P</i> < 0.05 and **<i>P</i> < 0.01).</p

The <i>y-maze</i>.

<p>The system was designed to allow a focal <i>O. degus</i> to explore freely the three arms of the maze. Stimulus subjects were placed in chambers attached to the extremes opposite to the start chamber. A division plate prevented direct contact between focal and stimuli subjects, but allowed the airflow produced by a fan behind each stimulus chamber to circulate through the labyrinth.</p

Effects of early olfactory experience on <i>O. degus’</i> behaviours in the <i>y-maze</i>.

<p>(A) Exploration time (mean ± SE) of the <i>y-maze</i> arms by animals with different olfactory experience during early ontogeny (<i>eucalyptol</i> or naïve). Naïve subjects (controls) showed neophobia towards the artificial olfactory configuration (a conspecific impregnated with <i>eucalyptol</i>), exploring significantly less the <i>eucalyptol</i> arm (in black), subjects reared with <i>eucalyptol</i> (treated) explored similarly both arms. (B) Total time (mean ± SE) spent by both groups in each arm. Control subjects remain significantly more time in the control arm (in grey) and spent significantly less time in the <i>eucalyptol</i> arm than <i>eucalyptol</i> experienced subjects. Different letters represent statistically significant differences between the groups in each arm (<i>p</i> < 0.05, see text for exact statistical and <i>p</i> values).</p