Figure S1. Phenotypic and genotypic characterization for all putative hybrid individuals from
localities four and five. Red = A. reguloides phenotype or genotype. Blue = A. nigrocristatus
phenotype or genotype. Purple = intermediate phenotype or one halpotype from each parental
population. Gray = unique haplotypes, shared haplotypes, haplotypes that were not assigned in
PHASE to a parental population with a probability >90%, or the gene was not sequenced.
Parental phenotypes were determined by the range of a given character at localities 1-3 and 6-7
for A. reguloides and A. nigrocristatus, respectively. Hybrid/intermediate individuals were not
observed outside of localities four and five. MSB:BIRD: = Museum of Southwestern Biology
catalogue number for the sampled individual.
Table S2. Model selection for respiratory variables using AICc (Burnham and Anderson 2002). In the case of each dependent
variable, we applied the model with the best AICc score (see Table 3 for model results). All one to five parameter models that
included elevation or elevation x species identity (Q-score or species) were tested; models with equal or higher AICc scores than
simpler, nested models were excluded from consideration (Arnold 2010).
Dependent variable
Explanatory variables
k
n
AICc
ΔAICc
Relative heart mass
Elevation x Q-score, Q-score, mass
4
65
-821.00
0.00
Elevation, Q-score, mass
4
65
-818.60
2.40
Elevation, Q-score
3
65
-818.56
2.44
Elevation, Elevation x Q-score
3
65
-817.91
3.09
Elevation x Q-score, Q-score, sex
4
65
-814.05
6.95
Elevation x Q-score, Q-score
3
65
-813.86
7.14
Elevation
2
65
-813.10
7.90
Elevation x Q-score, mass
3
65
-812.36
8.64
Elevation x Q-score, sex
3
65
-809.19
11.81
Elevation x Q-score
2
65
-808.91
12.09
[Hb]
Hct
Elevation x species, species, mass, sex
6
48
40.77
0.00
Elevation x species, mass, sex
5
48
40.94
0.16
Elevation x species, species
4
48
41.30
0.53
Elevation x species
3
48
42.23
1.46
Elevation, species, mass, sex
5
48
43.16
2.39
Elevation, species
3
48
43.27
2.50
Elevation, mass
3
48
48.85
8.08
Elevation
2
48
49.37
8.60
Elevation x species, mass, sex
5
49
-312.89
0.00
Elevation, mass, sex, species
5
49
-312.08
0.81
Elevation x species, sex
4
49
-310.88
2.01
Elevation, sex, species
4
49
-310.52
2.37
Elevation, sex
3
49
-310.21
2.68
Elevation x species
3
49
-309.91
2.99
Elevation, species
3
49
-309.68
3.21
Elevation
2
49
-309.42
3.47
MCHC
Elevation x species, species
4
48
49.91
0.00
Elevation x species
3
48
52.03
2.12
Elevation x species, mass
4
48
52.65
2.74
Elevation x species, sex
4
48
53.07
3.16
Elevation, species
3
48
53.14
3.23