Electronic supplementary materials S1: Variables primarily considered in the analysis.
Each variable corresponds to values of 10×10 km UTM squares.
Variables
source
Topographical
Altitude
Slope
Cimatic
average annual temperature
average annual precipitation
solar radiation at ground (Total)
solar radiation at ground (Activity period)
solar radiation at ground (spring)
solar radiation at ground (summer)
solar radiation at ground (autumn)
Land-use habitats
Distance to forest
Distance to schrubs
Distance to open areas
Lithological variables Distance to granitic layer
Distance to limestone layer
Distance to sediment layer
Distance to metamorphic layer
Worldclim
derived from altitude
Worldclim
Worldclim
Worldclim
Worldclim
Worldclim
Worldclim
Worldclim
Corine (categ 23, 24, 25)
Corine (categ 26, 27, 28, 29)
Corine (categ 30, 31, 32, 33, 34)
One Geology
One Geology
One Geology
One Geology
Electronic supplementary materials S2: The accuracy of interpolations performed by
Kriging was evaluated by several metrics: the mean error that should be close to 0, the rootmean-square error that should be the smallest possible, the root-mean-square standardised
error that should be close to 1, and the average standard error. The zigzag characters
interpolated were: the total number of dorsal marks along the body (# Marks), the number of
scales inside the zigzag (# ZZ scales), the percentage of scales inside the zigzag (% ZZ
scales), the number of dorsal scale longitudinal rows (# rows), and the number of dorsal
marks in the body portion (# marks area).
N
Mean
root-mean-square
mean standardized
root-mean-square standardized
Avg standard error
spatial meaning
# Marks # ZZ scales % ZZ scales # rows # marks_area
143
178
178
178
178
0.078
0.017
-0.004
0.007
-0.020
4.135
7.381
7.126
0.807
0.796
0.013
0.001
-0.001
0.006
-0.025
0.942
0.987
1.062
1.021
1.050
4.352
7.479
6.690
0.788
0.750
yes
yes
yes
no
no