In the present study, we also found that the structure of groans changed between years according male quality, inducing a modification of vocal cues to identity.
In this case, do quality-related changes to the acoustic structure of calls induce a modification of vocal cues to identity from year to year?
Do all these observed age and rank-related changes induce a modification of vocal cues to the identity of bucks between successive breeding seasons?
Male quality changed with age, inducing a change in quality-related parameters and thus, a modification of vocal cues to male individuality between years.
A significant difference between same-year and cross-year correct classification rates would indicate a between-years modification of vocal cues to male individuality, according to the parameters measured in this study.
Same-year correct classification rates (36.09 ± 0.05%) were significantly higher than cross-year correct classification rates (21.62 ± 0.05%), indicating a between-years modification of vocal cues to male individuality (exact permutation test, P = 0.02).
To investigate between-years modification of vocal cues to male individuality, we then calculated percentages of correct classification of PC scores (corresponding to groans) of one year by a DFA carried out on a previous year (cross-year correct classification rate; function predict in R v.2.9.0) [ 56].
The evolution of a cerebellum would therefore seem to require a modification of either extrinsic signalling cues or responses within r1, in addition to the simple allocation of r1 territory.
This task was a variation of the visual discrimination task with two modifications: a) a delay of varying duration (0, 3, 6, or 9 sec) was imposed between trial onset (entry into the alcove) and presentation of the cue (the illuminated LED); and b) the duration of cue illumination was shortened to 700 msec.
Sweet cues: How heparan sulfate modification of fibronectin enables growth factor guided migration of embryonic cells.
