# SUPPLEMENTARY INFORMATION ```doi: 10.1038/nature08168
SUPPLEMENTARY INFORMATION
L = 256
10
L = 128
L = 64
5
0
6
Number of Species
S=5 G=25
Number of Species
Number of Species
15
Lognormal
100
1000
Number of Individuals 40
30
S=5 G=10
G
4
15
5
2
20
40
10
60
2
4
0
10
100
1000
Number of Individuals
5
6
S
7
0.5
0.0
80
70
60
50
40
30
20
15
10
5
2
1
1
20
S=6 G=25
1.0
8
4
100
1000
Number of Individuals
S=6 G=10
3
2
1
0
100
1000
Number of Individuals
Supplementary Figure 1. Species abundance and sampling area. We combine the species
area relationship and species abundance distributions to show how the species abundance varies
with sampled area for four different values of the parameters and three different size areas of
observation. (Peripheral panels) Species abundance distributions for four sets of parameters and
three sampling areas, LxL = 64x64, 128x128, and 256x256, from simulations of 8000 individuals
on a 256x256 lattice (errors similar to fig. 3d and 3f). Species with less than 8 members are not
included. (Central panel) Contour plot of the number of species formed as a function of the
maximum spatial distance, S, and genetic distances, G. For intermediate values of S, the number
of species is higher for intermediate values of G. Marked circles indicate the parameter values
for the four species abundance panels.
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1
SUPPLEMENTARY INFORMATION
doi: 10.1038/nature08168
a
b
1.0
26
24
G=30
22
n(r)
20
R 18
0.5
G=20
16
G=10
14
12
0.0
0
20
40
60
3
80
4
S
r
10
10
10
G=20
G=10
G=13
G=10
G=20
1
S=5
S=5
S=6
S=5
S=6
Q=0.3
Q=0.6
Q=0.29
Q=0.3
Q=0.3
d
R=20.1
R=20.1
R=20.1
R=16.1
R=22.9
0
-1
10
0
10
1
10
6
2
10
3
10
4
2
G=20 S=5 Q=0.3 X =3.1
2
G=10 S=5 Q=0.6 X =5.3
2
G=25 S=5 Q=0.3 X =2.8
2.0
number of species
number of species
c
10
5
30
1.5
20
1.0
10
0.5
-1
10
0
1
10
2
10
area
10
3
4
10
0.0
10
100
number of individuals
0
1000
Supplementary Figure 2. Parameter variation and model analysis: a) Average number of
individuals of a species between r and r+1 from its geographic center divided by the density of
sites (number of lattice sites between r and r+1 divided by r) for S=5 G=20, and L=256. The blue
line is n(r)=Arexp[-(r/R)2] with A=0.127 (approximately N/L2=0.122) and R=19.5,
corresponding to a Gaussian density distribution. b) The geographic radius of a species as a
function of S, G, (black) and as given by the analytic expression Eq. (2) in the text (red). c)
Species area relationship (see Fig. 3c) illustrating the effect of parameter variation. The
importance of the species radius R (Eq. (2)) to the species area relationship is apparent as black,
red and green squares have the same R and nearly identical species area relationships, while solid
and outline blue stars have lower and higher values respectively. Axes are rescaled to match
initial and final values. d) Species - abundance distribution (see Fig. 3d) showing data for
Panama trees (black stars) and three sets of simulations having χ2 values as shown. The general
shape does not change with parameters. The blue curve is the lognormal distribution.
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2
```