Figure 1.
Overview of study sites and contact call variation.
(a) Distribution of Platycercus elegans (grey overlay) showing recording sites. The yellow squares are recording sites with yellow phenotype birds; red squares are recording sites with crimson phenotype birds. The dots inside the squares indicate the mtDNA of the population: yellow dots = yellow subspecies (P. e. flaveolus), purple spots = hybrid Western Slopes population, red dots = crimson subspecies (P. e. elegans). The cut out gives a more detailed look of the six recording sites where the clines in microsatellite markers occur. The blue line denotes the Murray-Murrumbidgee river system. (b) Spectrogram with waveform of two contact calls from Berri (in the P. e. flaveolus distribution). (c) Spectrogram with waveform of a contact call from the clinal microsatellite area. (d) Spectrogram with waveform of two contact calls from Brungle (in the hybrid Western Slopes population).
Figure 2.
Plots of the microsatellite population assignment (using STRUCTURE) and all five acoustic variables clines.
Dots are the mean values for each individual. The three plumage forms/subspecies are indicated by dot colour as follows: P. e. flaveolus, yellow dots; the Western Slopes population, purple dots; P. e. elegans, red dots. Green lines connect the means of each population, and the dotted line within the vocalization plots indicates the microsatellite cline for comparison. At this latitude 1 degree of longitude is roughly 92km, and the transect changes little with latitude (Fig. 1).
Table 1.
Tests for fit of unimodal, bimodal and trimodal cline models for each variable (A), tests for common position of two vocalization traits with steep clines (B), and tests for common position of the vocalization clines and the microsatellite cline (C).
Figure 3.
Results from a Mantel test analyzing the relationship between vocal variation (Euclidean distances based on the five acoustic variables between all the recording sites) and geographic distances between recording sites (R2 = 0.143; p = 0.036).