Table 3.
Parameter estimates for the geographical clines shown in Fig. 4. The results for Structure and NewHybrids on the panel of microsatellites are taken as the reference. Significant differences with the 2log-likelihood unit support limits falling outside the range observed for the reference clines are shown in boldface type
| Model | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Character, unit | Type | Centre | Width | δ L | δ R | τ L | τ R | p min | p max |
| Microsatellite reference clines | |||||||||
| Structure, Q | fixN | −1.0 (−1.0–0.7) | 30.3 (21.5–44.4) | 0.016 | 0.983 | ||||
| NewHybrids, posterior probability | |||||||||
| - B. spinosus side of transect | fixL | −1.0 (−1.0–−0.2) | 0.6 (0.0–1.3) | 0.000 | 0.007 | 0.000 | 0.990 | ||
| - B. bufo side of transect | typR | 10.8 (8.4–20.0) | 12.2 (6.0–29.9) | 1.729 | 0.048 | 0 | 1 | ||
| Thresholds–min, max | −1.0, 20.0 | 0.0, 44.4 | |||||||
| Tested clines | |||||||||
| PCA on microsatellites, loading first axis | fixN | 4.6 (−1.0−15.7) | 104.9 (64.4–179.7) | −1.301 | 1.156 | ||||
| mtDNA, haplotype frequency | typN | −1.0 (−1.0–2.4) | 43.5 (31.0–64.0) | 0 | 1 | ||||
| Parotoids, classification probability | fixN | 65.5 (27.3–122.8) | 255.1 (107.7–> 400) | 0.142 | 0.769 | ||||
| Metatarsal tubercle, idem | fixN | 96.6 (54.2–145.3) | 298.7 (164.4–> 400) | 0.060 | 0.865 | ||||
| BDNF, allele frequency | fixR | 3.8 (−0.9–18.6) | 58.9 (46.9–115.8) | 0.505 | 0.274 | 0.023 | 1.000 | ||
| POMC, idem | optN | 22.3 (9.2–41.5) | 90.7 (52.6–176.7) | 0.187 | 0.951 | ||||
| RAG1, idem | typB | 4.0 (−0.7–9.1) | 35.7 (23.4–56.2) | 2.811 | 20.704 | 0.360 | 0.042 | 0 | 1 |
| RPL3, idem | fixR | −0.9 (−1.0–3.9) | 26.8 (23.0–49.1) | 1.064 | 0.507 | 0.050 | 1.000 | ||
For the chosen models p min and p max are fixed to 0 and 1 (typ models), or their empirical values (fix models), or p min and p max are fitted (opt model). Tail fitting encompassed right (R), left (L), none (N) or both fitted (B). Cline position is the centre of the contact zone and ca. equals the distance to Beaulieu (in km, population 10, see Table 1). Cline width (w) is calculated as 1/maximum slope. Two log-likelihood unit support limits are presented in parentheses. δ and τ are the shape parameters for the left and right tails, and p min and p max are the character states at either end of the transect